Extreme Flight Yak 54 74" 3500+ Watt Astro Monster Outrunner-Killer

[Team Astro]

Hello all,
I've been building the new Extreme Flight Yak 54 74" Arf. I decided to go with an all white version so I can cover it more like the EF Yak55 ep scheme. I like my planes to look unique compaired to others.

The construction is super light and very well designed. I would put this airframe on top with such greats as Stevens Aero, PA, and Fliton as far as electric ARF's or kits go. That is my opinion!

I want to thank our sponsors AstroFlight and Castle Creations for their help in all our projects And especially this one.

This is my first build thread so please ask all the questions so I can provide you with any information you feel is extremely helpful.

Ill wont bore you with step by step manual build. You can download the manual on EF web site. Chris has been very helpfull and interested in our e-version. I plan on having the yak flying this week end at The Wings For Kids in Ky. Is an easy ARF to build. A weeks time would be more than enough time to build a rock solid air plane. As detailed as the instructions are Im suprised they included it as easy as it goes together. I felt even with the 3500 watt system we dumping in it, all the included hardware is more than enough.

My choice of equiptment is as follows:
Brushless AstroFlight 8120 motor
Castle Creations HV 110 ESC
Battlepacks 5 cell Sanyo 2700 rx pack
4- Hitec 5985 servos for ailerons ans elevators
Jr matchbox for elevator seros
1 Hitec 5955 for the rudder
Vampower Jones Witch
Tanic 10s 1p 5000 cells

This same power systems been flying faithfully for 2 seasons in our Christian Eagle 2 (19#) the our 160 Ultimate (16 1/2#)
We are using a CF 18x8 prop that turns over 8900 rpm!
Draw 93 amps and 37+ volt under static loads
Over 3500 watts!!!

Our guestimated weight is around 14 lbs but Chris @ EF feels 11.5 to 12 lbs might be more realistic since thats the norm for most e-versions of the 74" Yak. TIME WILL TELL!

Our AstroFlight 8120 is the original prototype and is a 32oz version. AstroBob has since lightened the production run to around 28 oz.

Some features I found of great interest is the thumb screw wing bolts that
tighten by hand with out any tools. Stock Carbon Fiber wing tubes and stab tubes make removing either easy. The stab removes for travel or storage.

I was shocked at how tight the covering was when it arrived to my door. Every item was bagged and tapped in place. There wasnt a single mark on the plane. It was double boxed for shipping!

One new and exciting product I found (even though esprit models and atlanta hobbies carry them is the Cambria Tools SUM- super universal mounting system. I spoke with Chris with Cambria and he was able to get the right mount to me. Ive seen the 8120's mounted by the back plate and would not recommend it. You are asking 4 little screws to hold all the torque and power of the motor when they are designed to hold the back plate on the motor- PLEASE DONT MOUNT THE MOTOR FROM THE REAR PLATE ONLY!

Here are the pics of the motor install and a few shots of the equiptment I installed...

Well, thats all for tonight...
Terry
Team Astro
http://teamastroelectricsite.com
www.astroflight.com
www.castlecreations.com

[blucor basher]

Looking good.

We've done two of these as electrics.

#1 is a 12S3700 20C on a Hyperion 5035 spinning a 20" prop. Power is about 3600W. Plane flies really, really well at 12.5 lbs. We used big heavy stuff and it's still going strong after hundreds of flights.

#2 was 10S 5000 20C on Hyperion 5025 spinning 20X8 for about 2400W. Weighed about 11 lbs. Flew really well, I liked it better than the #1 plane, but it died at SEFF when I forgot to bolt the stab halves down and one separated in-flight.

On neither plane did we have to worry about nose weight. Lipolies went in the motor box and the Rx pack went behind them. On the big one, the Rx pack went to rear of the canopy hatch area. So, you may get to move your Lipolies back quite a bit since you have your Rx pack in the nose.

For sure, you'll enjoy it a lot!

[Team Astro]

Our 8pm test flight tonight told me the same thing. I will be moving the rx pack under the lipo tray. We are right at the reccommended cg and the elevator wants to be more tail heavy. It did hold a hover and okay pull out. Ill post more through the weekend as we will be flying it at a show this weekend. Wings For Kids in KY. Its a charity event for WHAS 11 Crusade for Children. Weight is the only issue. 15 lbs with this set up. We will be able to move to a 19x10 CF prop. The motor, pack and esc were all around 110 degrees after 10 minutes of hard flying. 230+ watts per pound, its not lacking power or vertical! I must get busy doing a little trim tonight as its not easy flying an all white plane!

[pmpjohn]

That should be one sweet bird. I will be watching this one as I have a project of my own I am planning on using this motor in.

I enjoyed meeting you guys at SEFF this year and swapping tall tales. Keep up the good work.

John Starks

[jonnyjetprop]

Keeping an eye on this thread. The biggest problem is the $399 price tag for the motor. Still I like to support the home team when I can.

John

[F1 Rocket]

Just about everything there is to know about these are covered here:

http://www.rcgroups.com/forums/showthread.php?t=577637

And here:

http://www.rcgroups.com/forums/showthread.php?t=630376

Cool looking motor though :)


Danny

[Jocke]

So if i got it right, its an inrunner with direct drive on 12s Lipo setup?

[jonnyjetprop]

Yes, it's an inrunner. Designed along the same lines as Steve Neu's ORK motors.

John

[Jocke]

Aha.. now i understand, thanks!

[pmpjohn]

At this point in time all the Astroflight motors are inrunners.

John

[Team Astro]

We are using only 10 cells with our set up. I will be stepping up the watts with a 19x10 for better 3-d. She weights @ 15 lbs but still flys sweet,none the less. We flew it this week end The Wings for Kids. AWESOME! I even got a custom Greg Popel paint job since it was an all white on top for the flight! Looked pretty good for spray bomb!!! Its all for the kids! Im sure youll see some pics floating around later! 10 minute test flight had our equiptment barely over 100 degrees with the new motor mount "heatsink"!
Ill finish my post after we get ready for next weeks DEMO at E-Hawks event in Hamilton, Ohio. Great club and great guys!
Terry

P.S> 12 cells and 16x13 will get you a 150mph plane if kept close to 12 lbs! 8120 is a beast!

[Bodywerks]

Not so sure I would trust a setscrewed prop adapter, Does no one make a collet adapter for that motor?

[Team Astro]

This is the first handbuilt prototype AstroBob made. The adapter now uses a pin through it and the shaft. The shaft is 3/8" so im not sure about a collet adapter. With the pin through the shaft and adapter, theres no way without shearing off the pin. I have filed flat spots and have edges to catch the set screws, also why we used 4. The production can is more steamline and a little lighter, around 28 oz. Since this has flown 2 1/2 years now and in a 19# Christian Eagle, 17 # Ultimate. Im not worried about the 15lb EF Yak. A 19x10 and it will be a 3-D machine! Ill guess hold more like 36.8-37 instead of 37.7 if the packs are still freash, 109 instead of the 93+ amps from the p-calc figures. It should give us a little watt gain and tons more thrust for 3-d, longer flights with the reduced throtle, too. Post all the info right here in the next week.
Not so sure I would trust a setscrewed prop adapter, Does no one make a collet adapter for that motor?

[Team Astro]

Yes, it's an inrunner. Designed along the same lines as Steve Neu's ORK motors.

John

Yes and made in the USA like them too. I wont knock a Nue motor, he makes a great motor, but depending the prop and application we have run tests that shown us that one smaller similar Astrofligt motor out perform the Nue More with larger size props. Now the Nue motor was better with the smaller prop. Bothe used the same Astroflight 710 gearbox and exact same prop fro the tests. Nue motors are one of the few I have to say can give an Astro a run for its money.
Our 8120 18x8 spins at 8900+ rpm on 10 cells and p-calcs to over 90% efficent. I like a sealed case design, my kids cant shove screwdrivers in them when playing (my 3 year old) nor do I drop bolts inside wholes by mistake. More aluminum the better since the can emilinates heat without letting dust or debris in the motor. Sure dust Metal shavings would take along time to affect it but it slowly would. Also the cobolt magnets wont de-mag if you run it too hot. Ive seen motors demag on madein flights, seen it happen. I feel these motors are designed to last your life time as long as you stay in reccommended specs. Again its our preference.

Cliff with Atlanta hobby has Bob making some 6 turn for larger props, 22x11 but I think its too much. Maybe a 20x10 or 22x8 would be more suited to the 6 turn. The 5 turn will do a 19x10 20x8 xoar on 10 cells and be okay with good throtle management. If Bob makes the 1/2 longer version It would make a da50 look sick. The more requests for it it and it might happen.

[Team Astro]

Looking good.

We've done two of these as electrics.

#1 is a 12S3700 20C on a Hyperion 5035 spinning a 20" prop. Power is about 3600W. Plane flies really, really well at 12.5 lbs. We used big heavy stuff and it's still going strong after hundreds of flights.

#2 was 10S 5000 20C on Hyperion 5025 spinning 20X8 for about 2400W. Weighed about 11 lbs. Flew really well, I liked it better than the #1 plane, but it died at SEFF when I forgot to bolt the stab halves down and one separated in-flight.

On neither plane did we have to worry about nose weight. Lipolies went in the motor box and the Rx pack went behind them. On the big one, the Rx pack went to rear of the canopy hatch area. So, you may get to move your Lipolies back quite a bit since you have your Rx pack in the nose.

For sure, you'll enjoy it a lot!

We love it even at 15lbs is a gem, 235 watts/pound its no slouch. Looks like you have some great set-ups too. I wish we could get Bob to finish the 60/90 series. A geared 90 would be super light with a huge prop! The market leaning towards driect drive for the average joe!

[Team Astro]

That should be one sweet bird. I will be watching this one as I have a project of my own I am planning on using this motor in.

I enjoyed meeting you guys at SEFF this year and swapping tall tales. Keep up the good work.

John Starks
Great meating you too John, let me know when you have a full Yak kit ready to go. The foamie to have no matter the power set-up!
Terry and Steve.

[sneu]

" 3500+ Watt Astro Monster Inrunner-Killer"

So based on the title it is going to kill it self? :) Got your title a little messed up I think!

Steve Neu--OutRunnerKiller maker:)

[Bodywerks]

Im not worried about the 15lb EF Yak.
WHAT???? This 1120 sq.in. 3D aerobatic-designed plane weighs 15 pounds with this powerplant???? That's almost a 31 ounce wingloading, or roughly an additional 1/2 pound per square foot of wing that it has to lift, compared to other proven powerplants on this exact airframe. I am sure the power-to-weight is absolutely killer, but there is no way it will 3D as well as the other electric versions of the same plane that are coming in at 11-11.5 pounds.
Not knocking the Astro motors, but this is definitely not the ideal setup for this size of plane if you are, indeed, coming in at that weight. It sounds more suited to the 16 pound Ultimate you had it in last, which I assume was originally designed for a 50cc engine, and therefore had about 1450 squares of wing

[callen]

We love it even at 15lbs is a gem, 235 watts/pound its no slouch. Looks like you have some great set-ups too. I wish we could get Bob to finish the 60/90 series. A geared 90 would be super light with a huge prop! The market leaning towards driect drive for the average joe!

With the Axi 5330/F3A on a 20x10 prop mine came in at 12lb 10 oz pulling 2900 watts on 10 S. Flies light. Mine needs a better pilot however it hovers as easy as some of my fomies.

[Team Astro]

Not really, the ultimate was not a good 3-d plane at that weight. When doing alot of manuvers the top wing doesnt even come into effect. Plus the pull out was not that great in a heavy airframe like the ultimate. Sure it was a great sport flyer but still took more throtle and power to fly it even in a sport manor. Untill a ultimate gets to 45% and up its not a great 3-d plane beacuse for alot of manuvers the plane doesnt fly on the top wing, so it has about the same wing loading in certian manuvers. Sorry you disagree, but you havent flown it either. I appreciate the opinion, but theres nothing wrong with the set up and yes the heavier plane will get toossed around less in the wind and be easier to control While in a hover. And there so many opinions on what 3-d is anyways what makes you think is wing loading that 3-ds a plane? Thats my opinion. If you never used this set-up or flown our plane how do you know. The GP ultimate was made for a 1.60 just the same as this plane, not a 50cc motor. GP Ultimate 1.60??? Sorry you dont argee but Im sure it will 3-d fine. When we do DEMOS, its not all about 3-d. We like extreme aerobatics too. I set up planes that will do a combination of things well. When Im tail touching it on the ground maybe youll feel different. But I also want it to tumble and have goot energy retention. Weight helps with that. Ive built airframes that when built light 3-d but wont tumble or do aerobatics well. Ive seen hover planes that wont snap roll. I want a plane that will do it all for our demo, cause not everyone want to only 3-d. Most people fly more sport and aerobatics. We show in this set up can do it all in this airframe. We do it without the mixing in the radio, coupling mixes, duel rates or tons of expo either, all straight stick work and thumbs. Im sure people value your opinion but its not YOUR ideal set-up. Im sure if Astro Bob built me a geared 90 I would have used it and dropped a pound or two. The weights not from the motor only but comes from other things like equiptment selection. RX pack, servo selection, using rx and matchbox, A proto-type motor thats heavier than the production run, and a beefy motor mount. I dont need a 5955 wit 3300z on the rudder but that was my chioce. ever other surface has 180 oz of torque. Heck the set-up flew a 19# christian eagle 2 from GP, now that is a 50cc plane but no 3-d plane. Tell me this when is a plane is 3-ding on the wing??? 3-d is flying in a stalled attitude and on thrust and prop wash, not the on the wing loading make it 3d. If its the wing why the huge control surfaces? How does flat foam fly 3-d??? POWER TO WEIGHT RATIO! Maybe you need to say on FG too. Seems like you all are such experts on telling others how bad there stuff is and it wont do this , that or the other. THATS YOUR OPINION. Do you even have one you fly electric with this set-up? Then dont tell me how my plane flys when youve never had your hands on my yak. Daniel from PA flown this set up in a PA edge at SEFF, 3-d's just as good as any thing else I seen and its @ 14-15 lbs too. Please dont tell people what you think it wont do unless you flown this set-up. It really just make you look bad later when it 3-ds just fine. 235 watts per pound, theres way more thrust than weight and some damn good thumbs is what hovers a plane. If it wing loading how would a 30+ lb plane hover and 3-d with with less than 1800 squre inches. I see that in 35-40% all day. A 747 flys on less than 30% power to weight. Hows that possable with its wing loading. DONT KNOCK IT TILL YOU TRY IT PEOPLE! AND DONT BEILIEVE EVERYTHING YOU READ ON THESE SITES. Thats one reason we have never posted on here pefore, everyone thinks thier experts and citisizes what they dont really know or understand or tried. How many times Ive heard a 010 wont 3-d a plane, but we been doing it for years with them. Take peoples info with a grain of salt. Come see our planes Demo at the shows were sent to and their performance will speak for it self.
WHAT???? This 1120 sq.in. 3D aerobatic-designed plane weighs 15 pounds with this powerplant???? That's almost a 31 ounce wingloading, or roughly an additional 1/2 pound per square foot of wing that it has to lift, compared to other proven powerplants on this exact airframe. I am sure the power-to-weight is absolutely killer, but there is no way it will 3D as well as the other electric versions of the same plane that are coming in at 11-11.5 pounds.
Not knocking the Astro motors, but this is definitely not the ideal setup for this size of plane if you are, indeed, coming in at that weight. It sounds more suited to the 16 pound Ultimate you had it in last, which I assume was originally designed for a 50cc engine, and therefore had about 1450 squares of wing

[Team Astro]

" 3500+ Watt Astro Monster Inrunner-Killer"

So based on the title it is going to kill it self? :) Got your title a little messed up I think!

Steve Neu--OutRunnerKiller maker:)
Sorry for the miss print, OUTRUNNER KILLER!!! And Bobs been at this a lot longer than we have. Sorry for the mistake. You make a great motor Steve. There right up there but some design differences that we prefer. Lee at Castle told me he could get us a good deal on some of your stuff. Cant say we'd ever change unless Bob just quits.
Do I remeber right that you won the world fai glidder comps years ago using his brushed ASTROFLIGHT motors? Id all love to here more about that some time. Ill try to get it changed Steve. Thanks for pointing it out.
When do you think youll run sonme test on some Astro Motors im your QF colums, I know Wil had a 8120 since after seff 2006 AND never seen any of them than the 010 I think??
Thanks
Terry

[Team Astro]

Yes, it's an inrunner. Designed along the same lines as Steve Neu's ORK motors.


John

Just to clear this up, AstroFlights been making motors since the 60's and alot of other companies follow his designs. The 8120 was the first large inrunner direct drive design I had seen produced for these larger planes. Everything else i see is giant outrunners or geared motors. Like the misinformation that e-flite/Horizon started the "name a motor compaired to the fuel motor it replaces". Bob started that with his brushed motors years ago.

[blucor basher]

I'd read this before posting any more. (http://findarticles.com/p/articles/mi_qa3819/is_199712/ai_n8772261)

[Team Astro]

Anyways back to the post...
I moved the rx pack back behind the equiptment in the fuse to help us get a more tail heavy plane. now the pack can be moved to adjust the CG to your preference. A simple ply plate and some wire ties. Heck its electric and theres not all that vibration to worry about. A little velcro and Wire ties goes along way.
Hers some more Pics...

[Team Astro]

The flight at The WIngs for Kids whas great. Greg Popel helped us put on a great show during our flight. It was the only big electric there. I got 4 stripes on the bottom at 2am before the show... Greg helped out with his own custom scheme for the top. LMAO- ya had to be there...
ITS ALL FOR THE KIDS>

[Team Astro]

I'd read this before posting any more. (http://findarticles.com/p/articles/mi_qa3819/is_199712/ai_n8772261)


I hope people also realise this is a artical on free flight models that fly on the wing, Ive never heard a free flight model doing 3-d... Although its an artical from 1997 it starts and is based on a theroy from 1959. But 3d and 2d are mentioned in the artical, but not as hovering manuvers. As I said, dont believe everything you read on forums, this is why we never posted till the past year. Take it with a grain of salt. I post my opinions, just like you do yours. I wont loose sleep cause i know im sharing truthful and factual info. If all you want to do is knock the thread, Ill have you and your post removed. Im sharing the information on our set-up. You are getting petty thinking you just know it all. I thought forum were to share and information, your just being bias about what you feel. The artical mentions wing loading is 3 and 2 dimentional, not based on 3-d manuvers.
Terry

[Team Astro]

Here what our friend Dan posted to the flying giant post...

Re: Extreme Flight Yak 74" 3500+ watt Monster outrunner killer

--------------------------------------------------------------------------------

hey guys, i had the chance at SEFF to fly a PA Edge 540T 84" with the same motor / esc Terry is running, plane weighted 14-15 lbs, man that astro flight motor has crazy power, you need to prop up! Terry you need to get rid of that heavy 2700 6v nicad that thing alone weights like one pound more LOL!
__________________
Daniel Dominguez
www.aerofunrc.com


You guys need to quit bashing whay you dont know or try. I appreciate others posting there set-ups and info, if you think you know it all, i bet you Astro Bob forgetten more about electric flight than most of us will ever know in a life time. He is the pioneer of electric flight!

[blucor basher]

Delete.

Enjoy the airplane. I'm out.

[Bodywerks]

Not really, the ultimate was not a good 3-d plane at that weight. When doing alot of manuvers the top wing doesnt even come into effect. Plus the pull out was not that great in a heavy airframe like the ultimate. Sure it was a great sport flyer but still took more throtle and power to fly it even in a sport manor. Untill a ultimate gets to 45% and up its not a great 3-d plane beacuse for alot of manuvers the plane doesnt fly on the top wing, so it has about the same wing loading in certian manuvers. Sorry you disagree, but you havent flown it either. I appreciate the opinion, but theres nothing wrong with the set up and yes the heavier plane will get toossed around less in the wind and be easier to control While in a hover. And there so many opinions on what 3-d is anyways what makes you think is wing loading that 3-ds a plane? Thats my opinion. If you never used this set-up or flown our plane how do you know. The GP ultimate was made for a 1.60 just the same as this plane, not a 50cc motor. GP Ultimate 1.60??? I used the term "3-D" loosely. In general, all types of aerobatic flying suffers with higher wing loadings, even when you are in high-alpha-type flight. A perfect example is in an Elevator maneuver, where the only thing keeping the plane from falling like a rock is the area of the wing and fuse. Your plane, being significantly heavier than its counterparts, will fall much faster. In general flight, the plane has to fly faster and/or at a higher angle of attack to maintain lift. When a heavily loaded plane stalls, it does so with less warning and takes longer to recover. It is a heavier plane with the same amount of control surface area as its lighter counterparts and, therefore, it will not respond as quickly to control inputs when in a hover. These are all facts, not my opinion. I never knew the exact Ultimate you had, but for all practical intents and purposes, the GP Ultimate 1.60 IS a 50cc plane. They recommend an OS 160 or a FUJI 43 only because Great Planes is a distributer of those engines. All other Ultimates "labeled" 50CC are the same size as the GP- some are even smaller! I have that Ultimate with a DA 50 and it is 15.5 pounds with a full tank of fuel. It harriers, harrier rolls, torque rolls, tumbles etc. just fine, due in good part to its light wing loading. And, because it has such a light wing loading , it floats quite nicely and lands like a trainer. I have seen the exact plane at 17.5 pounds wet fly and it is not as nice. I don't know what you mean about the top wing having no effect in certain maneuvers - I don't see that being the case.Sorry you dont argee but Im sure it will 3-d fine. When we do DEMOS, its not all about 3-d. We like extreme aerobatics too. I set up planes that will do a combination of things well. When Im tail touching it on the ground maybe youll feel different. But I also want it to tumble and have goot energy retention. Weight helps with that. Ive built airframes that when built light 3-d but wont tumble or do aerobatics well. Ive seen hover planes that wont snap roll. I want a plane that will do it all for our demo, cause not everyone want to only 3-d. Most people fly more sport and aerobatics. I am not strictly 3D, either. I do a lot of rolling maneuvers (loops, humpty's, eights, and other variations), precision snaps, slow rolls, point rolls, etc. In all those aspects of flight, lighter wingloadings are better. "Energy retention in a tumble" - I'll give you that. That's because the plane has essentially stopped flying and is just a rock in the sky. The heavier that rock is, the longer it takes to turn it into a plane again. Do it too low, and you will be wishing you had a lighter wing loading. Tell me this when is a plane is 3-ding on the wing??? 3-d is flying in a stalled attitude and on thrust and prop wash, not the on the wing loading make it 3d. If its the wing why the huge control surfaces? How does flat foam fly 3-d??? POWER TO WEIGHT RATIO! The wing, and the weight of a plane for it's size ALL STILL come into play in "3-D", even hovering/TRing. High wing loading planes are more "tippy" as the approach stall as well. And for any given AOA above the stall angle, if you put two of the same planes like yours side by side, one at 11 pounds and one at 15, the one at 15 pounds will have to fly faster to maintain the same altitude. Again, this is a fact, and proof that wing loading plays a part in 3D. As for the foamie remark - it just made me realize that I don't know why I am even arguing with you. If you think it's POWER TO WEIGHT alone that makes a foamie great for 3D and as a general extreme aerobatics training tool, then I give up...Maybe you need to say on FG too. Seems like you all are such experts on telling others how bad there stuff is and it wont do this , that or the other. THATS YOUR OPINION. Do you even have one you fly electric with this set-up? Then dont tell me how my plane flys when youve never had your hands on my yak. This comment from a sponsored pilot...I won't even go there. Daniel from PA flown this set up in a PA edge at SEFF, 3-d's just as good as any thing else I seen and its @ 14-15 lbs too. Dude, that plane has like 10 inches more wingspan and 200 more squares than yours! No comparison... Please dont tell people what you think it wont do unless you flown this set-up. It really just make you look bad later when it 3-ds just fine. 235 watts per pound, theres way more thrust than weight and some damn good thumbs is what hovers a plane. If it wing loading how would a 30+ lb plane hover and 3-d with with less than 1800 squre inches. I see that in 35-40% all day. A 747 flys on less than 30% power to weight. Hows that possable with its wing loading. Again, if you don't understand how wing loading increases as the size of a plane increases, and don't understand how a 74" aerobatic plane with a 31 ounce wing loading(the wing loading of your plane) will fly like a rock compared to a 104" plane with a 32 ounce wing loading (the wing loading of my 35% 260), then I guess I really am just wasting my time. It's called reynold's numbers, look it up. Also look up cubic wing loading... DONT KNOCK IT TILL YOU TRY IT PEOPLE! AND DONT BEILIEVE EVERYTHING YOU READ ON THESE SITES. Thats one reason we have never posted on here pefore, everyone thinks thier experts and citisizes what they dont really know or understand or tried. How many times Ive heard a 010 wont 3-d a plane, but we been doing it for years with them. Take peoples info with a grain of salt. Come see our planes Demo at the shows were sent to and their performance will speak for it self.Have you considered, perhaps, that your demeanor on here, Flaunting that you are a sponsored pilot, yet typing the way you do and not responding to criticism or suggestions with a little tact, already gives people preconceived notions that maybe you think you are some sort of RC God and we are all just pee-ons? Does Astroflight read your comments here?

[Team Astro]

Here again,
Im not here trying to argue your opinion. But fact, wing loading has nothing to do with hovering a plane!!! I can agree it can effect transistion and some high alpha manuvers but doesnt mean a lighter plane flys better. This plane does it all well even at this weight!
I know pilots who will argue with you about bipes and the top wing does not
all ways come into play during certain manuvers. They fly for sponsors too.

Ill bet this 15 lb plane will get tossed around less and be easier to fly in windier conditions than it at 12 lbs. Since its usually windy here, I like the feel of the plane. Its all pereference. Its a shame you forget how differently
everyone is and what they want can differ too.
The sad part is you knocking what Im sharing on my post. Doenst make it a better plane because its lighter. You may like it better lighter, but doesnt make it a better plane. Again, your opinion! Maybe it takes a better pilot to fly this plane if being lighter it will 3-d better. In fact ill bet youll say it wont 3-d with out tons of expo too. I fly with almost no expo and no mixing in my radio. I use a simple 6102 from JR. All your doing is making other people think they never acheve what you have with out doing as you do. Ill never agree with that. There many ways to travel across the country coast to coast. Some will follow others, and some lead the way and do different things. My piont...
Everyone prefers different set ups. Its a same you cant share your opinion on line without some attacking what you have to say cause its not what they were always told.
Steve and I have been flying electrics for 4 years together and Steve even longer. Hes been flying 20 years so Im sure we have no clue how to set up or fly planes.
Some say you need a big prop to 3-d, but you dont.
I sure youll say a GP super-sportster wont hover either, but Ive seen it done. How about a Volts, a Cub, or a . Steves hovered one too. If we all believe everything we heard and never tried new things we never learn new things.

I just put two flights on this plane today at our weight, and it one of the best fliers I have had so far.
Its a shame to hear you would think I implyed to be a r/c god, because I said Im sponsored- when the fact is I use my sponsors equiptment. This is what they offer for this size plane.
The plane will do all the same stuff at 12 lbs it will at 15lbs. Never said it wont take more throtle, get less flight time, or anything like that. YOU ALL ARE ATTACKING MY SET UP AND OPINIONS. Imure my sponsors wont have any problems with my opinions or set-ups, but your not worth my time to argue about what you thinks better. THATS YOUR OPINION. Yes I seen your ummm... on FG where they try to give me BS over this post too.

Now I see why so many refuse to get on line and share there experiences and set-ups simply cause theres always someone trying to claim I know more or am better than you and you dont have a clue. If you dont like what you hear go read something else. Sorry you might not be open minded to this set-up or my opinion, but its just as valid as yours, I dont rember knocking your opinions on your posts.

Whats funny is most flat wing foam planes fly cause of power to weight. Theres no airfiol to create lift.
Sure the bigger the plane the better they handle weight. But if its lighter better, how can Frank Knoll do power off rutines at shows if a plane has to be light to fly good- energy retention??? A light plane wont cut the wind as well as a heavy plane and get tossed around more, ask someone who flyies fast planes.
Anyways have you flown this plane I built? so how can you say anything about how it will or wont fly, cause others who have will disagree, theres nothing wrong with the weight or set up, or wing loading for the plane.

In fact te guys who started hovering and profiles fly at our club. Morris hobbies, started by Doc Morris, Tony Aiers, Tom Stryker, and one watched my plane fly today.
Its ashame so much BS has found its way in to a hobby.
All I can say is this my thread, my opinion and what Ive learned from the profesional and no pros ive meet and fly with over the years. Take whats said with a grain of salt, cause on here- EVERYONES SOMEKIND of R/C GOD!!!

[mexico]

This is some thread. Just because 2 people disagree doen't mean it is an attack. Chill out.

And I thought flat plate foamies flew based on AOA.

[Team Astro]

This is some thread. Just because 2 people disagree doen't mean it is an attack. Chill out.

Disagreeing is one thing but some of the comments are unnessary. This same guy started in on another sight too. Suppost to be a electric guy. Lighter is better is an opinion like a yak is better than an extra. To many variables to think theres only one way a plane should be set up.

And I thought flat plate foamies flew based on AOA.

Not all planes are the same. Flat wing doesnt fly flat and level from anything thats normal to do with a airfoiled wing flying. Higher alpha I could understand AOA in foward flight or people using wind to harrier foam and planes. In a straight up and down hover, theres no wing surface involved. a true hover is not on the wing by any means and has nothing to do with wing loading but power to weight ratio was my piont. wing loading doesnt do much if the wings stalled. Thats more like thrust vectoring. The usaf a harrier jump jet does hover from power to weight (thrust Ratio). Whats the wing loading have to do with that.
Not all planes and designs act the same. Why does everyone think its all the same no matter what plane! Thats like saying all people are the same and act and do the same thing. Im sorry I have such a comman sence look at models, cause they dont fly like full scale and usually are designed nothing like them. Too much bad info out there being thrown around that people believe cause its what they always heard. Thats why im so discurraged about even posting any more. I appreciate the way you posted your opinions, not acting like Im a idiot cause i think this way about what i learned or feel.
Terry

[mexico]

This thread is supposed to be about your Yak so I don't want to beat a dead horse BUT - I understand that different flying styles might require different setups. Precision pattern planes have different wingloadings than freestyle models and smaller throws etc. And I do agree that light wing loading can be taken too far even in freestyle/3d planes - too floaty- won't snap. But within reasonable limits 2 identical planes - one setup 25% heavier than the other - I too agree that the lighter plane will fly better. That is not to say you cannot like the heavier one - you can like whatever you want. But the vast majority of rc pilots would prefer the 11 lb yak's flight characteristics to the same Yak at 15 lbs. - Just my opinion.

Now back to your plane.

[pmpjohn]

How will "the vast majority of rc pilots" know that they prefer 11lbs vs 15lbs with 1000 extra watts if they have not tried it?

John

[mexico]

As I said - it is my opinion that they would. Never claimed it was a fact - just my opinion.

Just to play devil's advocate why stop at 15 lbs. Why not add a couple thousand more watts and fly it at 20 lbs. Should be even better right?

[Team Astro]

[QUOTE=mexico]As I said - it is my opinion that they would. Never claimed it was a fact - just my opinion.[/QUOTE

Thanks,
Ive stated before, If Astro Bob had his 60/90 series done, I would gone with a geared 90, but then of corse if its geared then that would be the arguement. Im sure it would be a lighter set-up with such a geared motor. Its not avaiable yet for me to have an opinion. This is what my sponsor has and a I love the power 120 (4stroke)size electric motor in a 160 size plane. Im still at 235 watts per pound as the lighter set ups and will be more when I prop it up. Should 3-d even better. I liked it wasnt blown off corse in a hover. I have 25-30 expo only just to help landing. No duel rates nothing coupling programed. This plane made me look good. I got alot of compliments today as i flew it.

I more so than anything appreciate they way you stated your opinion other than just dogging mine and saying why its too heavy or I wont like it.

BIG PROPS MEXICO!!! THANK YOU!

I am going to change Props to a 19x10 like Dan test flew at SEFF in his PA EDGE.
Todays flights were great. One 6 minutes took 2500 mil and the set up came in under 100 degrees. I wasnt putting around. Knife edge, high alpha Knife edge , rolls, long rolling verticals, blenders, pulled out of a hover, even got through a sudo torque roll, all done high up. Second flight I let loose some...Slammed elevator up and down snap and 1/2, slow and fast. Tested stall and full up and down elevator at slow and fast speeds. I was suprised the yak wouldnt snap out but almost walled- flapperon will fix it I hope. Inverted too, slight wing rock in parachutes and only a slight wing drop on the stall. I havent laterally balanced yet since Im not done with trim. Stall recovered in 1/2 second. This sure didnt act like a overweight plane to me. Sure it didt fly like a foamy but was solid and tracked perfect with little cupling and it was a steady 15 mph wind. I sure wont knock the airframe!

Like John says, dont knock it till you try it! This is a GEM and 1/2 with the chips-LOL.. :)

For those who want light Call Radical Dave and have him cut you his 80" vertigo. its dry frame covered is 5lbs. We guessed 11-12 lbs with ths set up. I would have built it but we agree too much power and would blow the air frame apart the way we fly!

To lighten it with the motor/esc I used- Swap to a UBEC, Go standard servos 1.5 oz (100 oz torque)not 2+ oz each(180 oz torque/330 oz on rudder) build the carbon foam sandwitch motor mount I seen in a thread and use a production run 8120 and 4000 mil cells. You would shave a 1 1/2 to 2 or more pounds if I guess right. Still have 3000+ watts more with good cells at a much lighter weight.

I wanted to show an Astro system you can just bolt in, not have to build a motor mount or anything. Few People build anymore, so what good does it do to demo this in a plane that special built to be light. The power of the motor off sets any weight disadvantage compaired to its fuel conterpart. Heck it flew a 50cc Cristian eagle 2 but lacked unlimited vertical as it has now. The Ultimate 1.60 wouldnt hover or 3-d well due to weight.
If I wanted super light Id buy plans and scatch build, but most people want Arfs that assemble in a week or less. This one will with all the hareware straight from the box. Other arf I found myself upgrading hardware, this hardware can handle this monster set up. Has so far, no flutter and I know opened up over 90+mph.
We guess less than 500 rpm drop with the 19x10. Looking into a xoar as thats what AstroBob tests with now. That my opinion on this build. Still have trim work to do. Thanks to those who check out my plane with an open mind.
Terry

Cambria Tools makes alot of mounts for other motors too.

[Team Astro]

As I said - it is my opinion that they would. Never claimed it was a fact - just my opinion.

Just to play devil's advocate why stop at 15 lbs. Why not add a couple thousand more watts and fly it at 20 lbs. Should be even better right?

LOL- We will but, well add a few thousand square inches and bigger wing span. It will be a 35%. The funny part I didnt realise you were being smart when I was trying to be nice that you stated your opinion.

This is a 160 size plane 160 size motor. Sorry it seems so heavy to everyone else but It flys like a dream to me. You prefer other set ups, great tell us what they are. I wont tell you there not right, or not good enough, or too heavy. For some reason everyone else want to tell that to us. Please just take our post for what it is, how I built my Yak. It upsets people to tell them what they want to do is too heavy or wont fly as good. Thats opinions guys and we should all express our opinions to help people,not be smart or jerks. Unfortunatly though it happens. I wish I didnt, but nothings perfect. Im done with the post.It is nothing but a joke now, when all I wanted was to share our build.
Thanks to those who support our effors and sponsors.
Terry
Team Astro

[tIANcI]

I envy you guys ... I got the plane but do not have such a set up, best I can get is about 2,200 W.

[mexico]

The funny part I didnt realise you were being smart when I was trying to be nice that you stated your opinion.



Not sure what you mean by this. The post asked how I know pilots would prefer the lighter setup. Basically I said that I don't "know" it. It's my opinion. Nothing smart about that. Sorry if I offended anyone. Not my intention.

unsubscribed.

[Team Astro]

Not sure what you mean by this. The post asked how I know pilots would prefer the lighter setup. Basically I said that I don't "know" it. It's my opinion. Nothing smart about that. Sorry if I offended anyone. Not my intention.

unsubscribed.

Sorry but, I ment the lets go 20 lbs with few thousand more watts comment, not saying your being smart--- but thought it was funny "smart" remark! Sorry for our misunderstanding of the comments or quotes. You didnt offend me if you worried. Thanks for the concern.

I wanted to add some information on a New prop we well be trying. I calced the motor info for the 19x10 and Dan with PA test flew it @ SEFF. I talked with Xoar Props. These are new electric version , lighter prop. He recommended the 20 x 8 since the 19x10 not avalable in e-series. In theroy they should load similar from the tests they ran. I have not tested but want more Prop for the hover and 3-d side. The 18x8 is awesome prop, not as suited for 3-d or hovering very close to the ground since the pull out could be better. I wanted more thrust. Guessing a 500-600 rpm loss (few MPH of the 90+ top speed) and get us up to close to 20+ lbs thrust I want. Im sure Ill scarifice flight time by a minute maybe. Its all speculation till I run tests. This should better suited to the weight we fly our plane at. Ill post what numbers I can and a pic of the finished covering on the plane.
Terry
Team Astro

[Team Astro]

I envy you guys ... I got the plane but do not have such a set up, best I can get is about 2,200 W.


Whats the set up you are using? Im sure other would like to know too. Include servos and all.

I weighed the dry airframe in peices before we assembled it. It was with equiptment in the bags to give us our original 14lb estimate. 123oz, so 7 3/4 lbs. A good dry estimate with some glue instead of bags. Anyone else do a dry weight??? Id be interested inknowing if I have a bad scale! 75 lb capacity (.2oz tolerance).

[Jocke]

I like the idea of using an inrunner for direct drive, been testing and flying alot with inrunner on DD for motor/aerobatic/3D planes/setups up to 14s, using Pletti Freestyles and HP300 HP370 mainly and they have worked very good, giving me long flight times on the time nimh was standard, and a cool setup not getting overheated thanks to the design.

Can you tell more of the design of the motor, poles, weight, max eff, current, voltage ?

How is your trotteling on high voltage, you need time delay on the trottel?

[pmpjohn]

Jocke,

Motor specs,

http://www.astroflight.com/store/store-type-tem.html?item=products:af-8120&sid=00010GuHtKuuGPgkiw0U6E2

John

[Jocke]

Ah... there it is... thank you!

[pmpjohn]

Your welcome

[Team Astro]

Thanks John for linking to the site info. we calced the motor with the 18x8 at 90% eff. Ive not calced the new prop yet but will post info ASAP.
The 18x8
volts -37.7 and 93 amps- accual test at Hamilton e-hawks event last year with the old astro watt meter that goes to 100amps. Dave witnessed it and will back those numbers.

the 19x10 were wanted:
In theroy will draw similar to the 20x8 we will be using
37 volts and 109 amps on the calc- no accual tests yet... but I will post p-calc info when I get there. The old watt meter only does a 100 amps right now, so I will have to get voltage reading then p-calc to estimate amps, etc...

Calc numbers ran slightly higher than the accual tests with the watt meter.

We programmed a soft cut off and standard timing in the esc. Motor start up is med at 59% with no no brake. No delay on throtle just med start up. I havent tried the 100% start up, it could create more torque issues with the bigger prop. We'll find out soon enough. I also run insensitive, so it will cut off, but not prematurely. I can only recommend these setting for this motor. We had to keep trying and testing new thing to see what felt best in flight and landed the coolest after.

These are new programing features of the CASTLE ESC. One reason they are the only ESC I use. The Astro motors are designed and tested with them and the programability is far beyond what i have seen. I even bought a lap top so I can program at the feild and at shows when need. The castle link is the BOMB!!!

I give credit to the new Cambris Tool SUM mount (like bolting on a heat sink) and the open yak cowl for the system running super cool now. We have dropped 40-50 degrees in temp all around on the set-up.
My experence with certain cowls, like ultimate, eagle, caps, I had to build ducking to get air to the motor. With SUM mounts, unlike my old wood built mounts, it leaves more motor exposed. This is my first mount, I am only stating what seems to make sence.
Thanks
Terry

I like the idea of using an inrunner for direct drive, been testing and flying alot with inrunner on DD for motor/aerobatic/3D planes/setups up to 14s, using Pletti Freestyles and HP300 HP370 mainly and they have worked very good, giving me long flight times on the time nimh was standard, and a cool setup not getting overheated thanks to the design.

Can you tell more of the design of the motor, poles, weight, max eff, current, voltage ?

How is your trotteling on high voltage, you need time delay on the trottel?

[Team Astro]

Here you go guys....
Check out FLY R/C Mag. May 2007 edition. 77" Carl Goldberg Edge converted with the set-up- different battery manufacture. It will give you another opinion on a similar size plane!
Terry

[Team Astro]

Here goes part of the covering scheme...
Its not custom by any means not complicated. its a traditional yak type scheme in our team colors. I am not decided on a center stripe, its size or color. Your opinions would be welcome on that. Im sure the yellow would look best for a stripe but i want close to 3/4" width...

So far the top of this shceme has all been cut from monokote and sprayed with lustrekote I found at the local Hobby shop. The Bottom was done in matching monokoto trim sheet to keep it even easier!

Insignia Blue and Missle Red are the colors.

[aerofundan]

nice stuff terry!, keep us updated on the progress of the color scheme, that thing must have crazy power, cause the PA Edge 84" at 14-15 lbs with that system had TONS of power! post more pics of the plane color scheme when you finish covering it! :)

[Team Astro]

nice stuff terry!, keep us updated on the progress of the color scheme, that thing must have crazy power, cause the PA Edge 84" at 14-15 lbs with that system had TONS of power! post more pics of the plane color scheme when you finish covering it! :)


Thanks Dan, I will...

Your rang that edge out for all it was worth, God blessed your thumbs!!!-LOL

Some guys dont build, but do arfs. I want to share some stuff i learned about covering and this is a great and easy way for guys with less time to get a one of a kind scheme, by starting with a solid color arf. If it helps one guy its worth it.

Ill keep posting progress and some vids as we get them shot!
Terry

[Team Astro]

Here it goes, this is our 6th flight. Although we shot some video, We didnt get all we did in before the battery died on the camera. The 20x8 Xoar spun at just over 8000 rpm. Awesome thrust, pull out and vertical!!! I like the prop, but it seemed to have some tip flex in the hover, alot less than any e-series other than CF. Very please but will go with the mejzlik CF 20x8 e-series to get every last pit we can out of the prop. Here some video- its not real great and a few pics of the wings minus the yellow stripe (special ordered) and some in flights. Video was shot on a digital camra- not a camcorder-

I guess ill have to get the video linked... any ideas???

[KatManDEW]

The video should already be on the camera in MPEG format. You could upload it directly from the camera, or copy it over to your PC first. You can also load it into Windows Movie Maker and add some titles.

[Keithf]

I've come to the conclusion that with Lipo batteries, we're carrying so much energy on board that motor efficiency doesn't really matter any more (to a point). After all, if you have a mediocre motor and have 20% battery capacity remaining when you land, or a higher efficieny motor and 40% remaining, who cares?

But it does bother me that many reputable motors apear to have quite poor efficiency, and do not warrant a price premium over (say) a cheap Chinese motor. Take the Astro 120 for example, and the quoted specs on their website:

Measured Performance on 28 volts (8 Lithium Cells)
Prop Amps Watts Rpm Thrust
16x10 APCE 52 amps 1456 watts 7,400 rpm 10.8 lb.
18x10 APCE 65 amps 1820 watts 7,100 rpm 13.5 lb.
20x10 APCE 78 amps 2184 watts 6,800 rpm 16.2 lb.
22x10 APCE 91 amps 2549 watts 6,500 rpm 18.9 lb.

Measured Performance on 35 volts (10 Lithium Cells)
Prop Amps Watts Rpm Thrust
15x10 APCE 60 amps 2100 watts 8,600 rpm 12.5 lb.
16x10 APCE 75 amps 2625 watts 8,200 rpm 15.6 lb.
18x10 APCE 90 amps 3150 watts 7,800 rpm 18.7 lb.
20x10 APCE 105 amps 3675 watts 7,400 rpm 21.8 lb.

Measured Performance on 42 volts (12 Lithium Cells)
Prop Amps Watts Rpm Thrust
14x10 APCE 60 amps 2520 watts 10,000 rpm 12.5 lb.
15x10 APCE 80 amps 3360 watts 9,400 rpm 16.6 lb.
16x10 APCE 100 amps 4200 watts 8,800 rpm 20.8 lb.

The first quick-and-dirty estimate of efficiency can be gleaned from power absorption formulas for propellers. Different brand props will have different k-factors, so the results are only indicative, but generally reasonably close.

Lets look at the 16x10 results quoted by Astro:
1456 watts 7,400 rpm - calculated power approx 1150W, so efficiency 79%
4200 watts 8,800 rpm - calculated power approx 1920W, so efficiency 46%

The second quick-and-dirty comes from the fact that power requirements increase with the cube of the RPM. So 8800 RPM from 7400 is an 18.9% increase. If Astro's quoted 1456W was correct, then 8800 RPM should require 1456*1.189*1.189*1.189=2447W. Their data shows 4200W instead! Either their quoted data is defective, or the 46% efficiency is corroborated! Why pay $400 for a 46% efficient motor? Get a Chinese one for $59.95 that'll be as good or better!

And it's not just the quoted 16x10 prop results that give these results. Other sizes give similarly disapointing results.

Motorcalc data will often give very rosy results based on quoted motor constants, but reality tells a very different story.

This is not an Astro bash, BTW. I've found similar results with Hacker and Hyperion outrunners. Plettenberg and Kontronik results seem to fare much better.

This may be a conspiracy theory, but is it just coincidence that of these 5 brands, only Plettenberg and Kontronik publish efficiency graphs or tables? Could it possibly be that the others don't want the customer to know how poor their motors really are?

Again, I don't necessarily think that ultimate efficiency is everything, but I still don't like getting ripped.

[sneu]

I've come to the conclusion that with Lipo batteries, we're carrying so much energy on board that motor efficiency doesn't really matter any more (to a point). After all, if you have a mediocre motor and have 20% battery capacity remaining when you land, or a higher efficieny motor and 40% remaining, who cares?



Well this one deserves a response.

First off efficiency DOES matter --and for high power systems it matters even more! The easy example is the difference between 2 power syetems that can handle say 1000 watts. The first is 75% efficient and the second is 90%. You suggest that that little 15% does not matter much as the battery able to make up for the motors losses. Well think again. The 90% efficient motor will generate 100 watts in waste heat--the 75% motor makes 250 watts in heat--more than twice as much heat which means that the motor will run much hotter or will have to be much larger to handle the additional heating. Many overlook this simple fact and think that they can simply add more batteries to make up for poor motors. A efficient motor can weigh less for a given power level and can use a smaller battery for the same run time and power level.

As for the Astro data--you only have some prop data points. With out more information you can't make any conclusions regarding the efficiency of the motor. Motor efficiency is best from some sort of dyno that measures the input power and output torque and RPM. The data that Astro posted does not have all the needed info to actually even guess what the motor efficiency is with any accuracy.

Judging from what I have seen of the Astro motor it is likely much better than you suggest.

Steve Neu
www.neumotors.com

[pmpjohn]

Thanks for that post Steve.

While I have no official connection with Astroflight I have been a satisfied customer for a couple of decades. The old brushed cobalt motors had better efficiency than Kiethf was claiming for the 120. Bob held out for quite a while before building brushless motors. His theory was the early brushless esc's lost more power than the brushes did.

Your post, coming from a recognised motor guru, and a competitor no less, should put this bs in the trash where it belongs before it spreads.

Kieth, why don't you buy an Astro and the cheap chinese motor and test them both. At least you will only have wasted $60.00.

John

[Keithf]

Steve,

I agree that motor heating etc is an issue, and thats why I qualified my statement by saying that efficiency doesn't matter to a point. I also see battery charge time and depletion of the field battery as being reasons to go for higher efficiency. I use a 96Ah field battery, and only get about 70Ah out of it before play has to stop. If 70Ah gives me 7 flights instead of 6 because of a more efficient motor, that's also a valid reason. For my money, I refuse to purchase poor efficiency motors.

In many cases these days however, comparatively poor motors are serving many flyers quite satisfactorily, due to the power density of Lipo's. If they were running Nickels, they may not be so happy. That's what my comments on efficiency were alluding to.

I also agree absolutely that dyno plots are the proper way to assess efficiency. But Steve, you've missed the whole point. Model aircraft motors aren't purchsed to fly a dyno. Dyno plots are the tool used to assess the characteristics of the motor, which are then used to ascertain the appropriateness of the motor to power a particular aircraft or turn a particular prop. Astro have already told us this. And they've given us quite a few data points, enough to make a moderate assessment of efficiency. Not as accurate as a dyno, but something.

Let me ask you this Steve, would you be happy if a NeuMotor consumed 4200W to turn an APCe 16x10 at 8800 RPM?

I must say though, its pleasing to see you stand up for another motor manufacturer.

Let's just hope that Astro's data is defective, and the motor is better than they say it is.

John,

BS? Maybe you should ask Steve if calling 4200W/8800 RPM/APCe16x10 inefficient is BS.

And heavens yes, we should always quash analysis that isn't complementary. Before it spreads. If modelers were to make informed decisions, sales might suffer. Nobody wants that.

And John, I'm not about to purchase the Astro or a Chinese equivalent, as I don't need either at present. I've just gone through the process of purchasing motors for a 3kW twin, and that's why I started looking into the efficiencies of some of the newer motors on the market. FWIW, I purchased Kontroniks. NeuMotors had an equivalent or better alternative, but had inadequate continuous power rating.

If Astro's quoted specs are correct, then I suspect you're also one of those flyers who's using Lipo energy density to make up for motor inefficiency. The fact that it works doesn't mean that its a good motor. Think about it.

[sneu]

Steve,

Let me ask you this Steve, would you be happy if a NeuMotor consumed 4200W to turn an APCe 16x10 at 8800 RPM?



If the motor were truly as inefficient as you suggest it would go up it smoke within a few seconds at 4200 watts. Since it does not seem to have that problem one can conclude that the test data is incorrect.

Steve

[pmpjohn]

The motor, pack and esc were all around 110 degrees after 10 minutes of hard flying.


This does not sound like the 120 is blowing off 1700 watts as heat.

John

[Jocke]

Not saying the Astro is inefficient, but i have runned more inefficent motor than hes sugesting, they havent runned up in smoke ;)

[Team Astro]

Well,
Thank you both Steve and John.

[Team Astro]

Well,
Thank you both Steve and John.
Steve Bayens and I also have no affiliation with Astro other than a few years ago we stepped up and started going to shows because we fly all Astro motors. Not because they are the best, but the best in our opinion. Our affiliation also stops at... they supply our motors for our projects.
Steve Nue makes one of the few motors on the market we feel even come close to the value and quality of Astro motors. For Steve to make such statements, I hope people put the Astro Flight beating to rest.
We get slack all over the place where we go, just as much as we find loyal users like John. Ive had people swear we running Hackers in planes we flown at shows, only to be speachless when they find we use Astro Flight.
Bob does accual tests and dinos motors before even sending new motors to us.
HE WILL NOT SEND OUT A NEW MOTOR BEFORE HE ACCUALLY TESTS IT AND KNOWS ITS OF ASTRO QUALITY. USUALLY THEY DO BETTER THAN HIS SITE CLAIMS.
WE DONT POST INFORMATION WE HAVENT TESTED AND COMPAIRED TO P-CALCS. WE EVEN USE AVEOX'S CALC TO DETERMINE THE EFFICENCY OF THE SETUP WE ARE USING. THIS IS THE INFORMATION WE POSTED.
Remeber we use an 18x8 on our 8120 taking 3500 watts to produce 8900 rpm. Aveox's p-calc says thats around 90% efficent. It quite possable Aveox p-calc isnt up to snuff, but I and others opinions would differ from such a statement. I feel its a very close to accual numbers and even free to use on Aveox website. They did pioneer the brushless motor, I would guess they have their stuff together.
I will even say, its Bob's sealed case that makes a difference for me. Id fly Nue motors as proudly, if I wasnt worried about my 3 year old sticking screwdrivers into holes in the motors. Shes done it before, so my chioce fits my life, as do most of our chioces in equiptment.
I wont bash your cheap outrunners, if they work for you great! I know I'll be flying my Astro motor years after youve replaced that outrunner many times. Like most things in life, you get what you pay for...
Quality cost money and Bob has his motors hand wound, and each wind tested to make sure the specs are close enought to make the motor run its best...
I doubt thats within quality specs and checks in a $49.95 motor.
Fly what you like, its a diverse hobby, but I believe in the quality and reliability of the products we buy.
We can usually fly our batteries to full or past capasity before the power falls off.
I had a 6-7 minute aerobatic flight on a 15lb plane with the 8120 and the 18x8 and used only 2500 mils form the 5000 mil pack.
The deeper you pull a pack down the shorter the life span of the pack. Our chioce to not pull packs till there dead is for max cycles on our equiptment, not cause we loose power to fly the plane.
I have an 840 geared motor on 4000 mil 6 cell pack that will fly aerobatics and hover for 12-15 minutes. It will even pull the pack to a 5 cell if you dont watch the flight time. No inefficent set-up would still have that type power to pull vertically unlimited, that far into a flight and use the battery almost completely.
Every think this could be a misprint of information on Astroflight's website before just claiming its inefficent!
Using a prop calc formual we see a 16x10 @ 9000 rpm should use 2.5kw and our 18x8 use 3.2kw @ 9000, so this has to be misprinted info. All this info is found in Bob's motor handbook. The efficency can be determinded buy the 3 constances without even running a prop.
Thanks to everyone who has supported us!
Terry

[Keithf]

Terry,

You're obviously a little tender about Astro products being challenged!

Just bare in mind that my comments were not based on my testing, they were based on Astro's published test results. And let's all just hope that their test data really is defective.

I must say, I find it amusing that after all the engineering that should have gone into designing and building the motor (magnetic flux analysis, winding patterns & densities, stator lamination materials & thicknesses, finite element analysis, etc, etc) they would stuff up something as simple as recording empirical test results. Really not doing themselves any favours.

[Team Astro]

Terry,

You're obviously a little tender about Astro products being challenged!

Just bare in mind that my comments were not based on my testing, they were based on Astro's published test results. And let's all just hope that their test data really is defective.

I must say, I find it amusing that after all the engineering that should have gone into designing and building the motor (magnetic flux analysis, winding patterns & densities, stator lamination materials & thicknesses, finite element analysis, etc, etc) they would stuff up something as simple as recording empirical test results. Really not doing themselves any favours.

I agree, if the info is wrong, it doesnt help the company. There are other calulations you can do to realise this could be mis posted info on the site as I believe that was Steve Nues point too. I am a believer in Astro products and most people want to bash his motors. Im just sharing our findings, but feel people try to say what I choose was wrong. Maybe thats why I seem touchy? Noone complains about the 109, but mention a Astro motor and there are alot of people who never knew they made motors, or their opinion is a bias one about his motors. His brushed mototrs were the pinical of electric flight for years. I just want people to remeber him and all the effort he has dedicated to electric flight.
Bobs designs lean towards sport and pattern flying, we are wanting to see more from the company and working with them to produce 3-d style motors too. I like the driect drive, inrunner and the sealed case design. Again I post my opinions and our test results, is all. Remeber Bobs been building motors for so many years, simple mistakes are more likely to happen by simply taking for granted his knowledge of the feild. Ive never tested that prop on that number of cells, so I cant tell you for sure, but dont think the info is correct. We talked to Bob today and he will recheck the info and make sure the correct specs will be posted.

[Jocke]

You are talking alot about calculations of the motor, not actually messurments, arent Astro dyno testing the motors ? or is the performance data only calulated in teory?

[twest]

Astrobob has always been a better engineer than marketer/advertiser. Astro brushless products tend to have "bland" outward appearances with good performance numbers. Many other motors have the opposite, and sell very well.

He is also slow to update his website. I've noticed several mistakes on the website as well (in the 120 motor's pdf, the 20-10 prop is listed as drawing fewer amps than an 18-10 on 35 volts).

Anyway, I'm very happy with my astro 'trex' 020 with gearbox in a funtana mini, and especially my 3-turn 40 in an e-sport. Rugged, dependible, and quite efficient (based on my unscientific methods of e-calc predictions, rpm/watt mesurements, and temp measurements).

For those who do use astro motors, the biggest selling points are usually long-term durability and inexpensive (here in the usa) repair service. I have astro brushed motors from 1991 and brushless from 1998 still working well.

[astrobob]

Yes our web site needs serious up dating.
I hope to post a revised pdf file on the 120 motor next week.
in regards to motor efficiency the 120 typically runs between
90 t0 95%. best efficiency is at 200 in ounces of torque
which corresponds to about 40 amps. At full take off power
static load of 80 amps eff is still above 90%
my dyno is limited to 200 inch ounces so we run high power tests
with props.

the data in the site is from tests made 3 years ago. with kontronic and
jetti controls set at zero advance. so there is noticeable torque droop
above 2000 watts but of a magnitude less then that found on outrunners.
now we have the newer castle 85 and castle 110 controls with automatic
phase advance so that torque droop is not noticable up to 80 amps.

automatic advance will give you almost 1000 rpm more on a given prop
at high power.

I have also modified my test stand. there was about 24 inches of wire between the 300 lb 3 phase power supply and the aliuminum pylon holding the motor during prop tests. we were using 13 gage wire and a std astro wattmeter limited to 80 amps. the new set up now has 10 gage wire reduced to 18 inches, and a special 200 amp wattmeter.

Hopefully this set up will give prop test results closer to actual model
experience.

I hope this clears up things a bit
thanks for reminding me to up date my site
astrobob

[SD_Raptor]

Interesting thread.

I have the Hyperion 74 inch Yak-54 which is essentially identical to the EF version. I started off flying the plane with the recommended Hyperion motor and ESC. After having the motor and ESC fail simultaneously in flight, I did some research and settled on the Neu 1515/3D with 6.7:1 gearbox, swinging a Mejzlik 20x11 CF electric prop. Electrical setup is 10S 4000 Lipos and Castle HV85 ESC. AUW is 11.5 lbs with CF landing gear from GraphTec and 4 cell receiver battery. Power is around 2200W at full throttle, 63 amps at 35 volts.

For full details on the setup my build thread is at

http://www.rcgroups.com/forums/showthread.php?t=630376&page=11

By progressively shedding weight, the plane has flown better and better, for all types of flying in winds up to 20 mph. About the only weight savings possible at this point is to switch from a receiver battery to a BEC to save a couple more ounces.

Many things to note:

1. Since the Neu pulls only 63 amps at full throttle in a vertical climb, I can safely use the HV85 ESC. If I needed more power, I could go 11S and get close to 2700 watts or I could switch to the Mejzlik 20x11 WE prop with about the same effect.

2. Because the Neu motor is very efficient, I can use 4000 mA packs and fly for 8 minutes of IMAC and use only 3200 mA-Hr on average. The setup in this thread uses 10S 5000 packs which is a significant hit on weight. The heavier batteries and ESC required for the Astro motor add at least 8 ounces of extra weight.

3. The Mejzlik 20x11 prop is extremely efficient. The blade tips do not visibly deflect at all in a full power static test. This prop is as efficient in flight as a 19x10 APCE prop but provide 20% more thrust at the same RPM (probably more since it is not twisting and bending.

4. The motor and ESC come down cool to the touch even after 8 minutes of solid IMAC flying. The batteries are only slightly warmed after a flight. The motor/esc/prop combination places little stress on the batteries. My batteries have well over one hundred flights and still hold voltage and current at nearly new levels.

5. Running the numbers in your original post, an 18x8 prop at 8900 rpm will provide somewhere around 360 oz of thrust for 3500 Watts of input power - 0.103 oz/Watt. But my Neu with the Mejzlik prop is giving the same thrust but requiring only 2200 Watts to obtain 0.164 oz/Watt. And since your plane weighs 15 lbs your thrust to weight ratio is 1.5:1 while my setup yields 1.96:1 for the thrust to weight ratio. Since thrust to weight is a crucial parameter for hover punch out, power on up lines for snaps and rolls, etc. it is obvious that the setup that I settled on is definitely superior for aerobatic flying. And I have headroom to prop up to the 20x11 WE Mejzlik prop to get even more power if desired.

My conclusion is that the Astro 120 is not a good choice for the 74 inch Yak since it adds significant weight not only for the motor but for the mount, batteries, and ESC required to use the motor. This extra weight not only limits the performance of the plane but adds stress to the airframe as well and makes landing much more challenging. And the lower cost of the ASTRO 120 is more than offset by the additional costs of higher current speed control, higher capacity batteries (particularly if more than one set are purchased), and greater wear and tear on batteries and ESC, as well as the airframe and landing gear.

Note also that for IMAC style flying, the downline speed of a 15 pound plane is significantly higher than for an 11.5 lb plane. This in turn implies that uplines should be longer and faster to present well and to allow time on the downline for smooth unhurried maneuvers like snaps and rolls.

I enjoyed flying my Yak when it was (by my current standards) obese. But it flies much better after shedding a pound or so of excess baggage.

Randy

[desert_flyer]

Randy,

A flameproof suit might come in handy at this point :D

[SD_Raptor]

Randy,

A flameproof suit might come in handy at this point :D

I am Rhino-Linered on the outside.

Hype hurts!

[twest]

I don't think anything heretical has been said here- a lightweight, efficient, geared inrunner (no, I'm not saying all geared inrunners are more efficient) will produce a lighter airframe and turn a larger diameter propeller than a big direct-drive motor. The big direct drive motor could be inrunner or outrunner- either way they will need to be relatively large and heavy to turn a big prop. As much as we might curse gearboxes- they are expensive, make noise, and need at least some maintenance- they allow a small, efficient motor turn a big, efficient prop.


I think most also agree that the airframe that is the subject of this thread might be a little on the small side for the astro 120, which is, after all, intended to put out 3000-4000 watts. I know that the astro is a good motor, as several people I've spoken with have used it and like it. Scott Scoopes had one in his 77 inch goldburg edge and had only good things to say abut it. But it is a heavy motor, and is not really intended for 11-13 lb airframes.

[desert_flyer]

I have the same motor as Randy but I wonder if I should have gone for one of the 19xx series Neu motors. The largest of these (1915 I think) would seem to have the power for this YAK and without the need for a gearbox, the motor comes in at 12 or 13 oz. Anybody tried one of these?

[SD_Raptor]

I have the same motor as Randy but I wonder if I should have gone for one of the 19xx series Neu motors. The largest of these (1915 I think) would seem to have the power for this YAK and without the need for a gearbox, the motor comes in at 12 or 13 oz. Anybody tried one of these?

DF,

The 1915/3Y comes close to the top end performance of the 1515/3D: on 10S the maxumum rpm are several percent lower giving less thrust on up-lines and less punch out power from a hover. For typical flying the 1915 will be about 85-90% efficient while the 1515/3d will be about 95% efficient. So to get the same total lfight time you would need batteries with 5-10% more capacity (and weight). The 1915 weighs 14.5 oz while the 1515/3D with gearbox and finned case is right at 20 oz. So, for the same total weight the 1515/3D has several percent more top end power.

[KatManDEW]

Running the numbers in your original post, an 18x8 prop at 8900 rpm will provide somewhere around 360 oz of thrust for 3500 Watts of input power - 0.103 oz/Watt. But my Neu with the Mejzlik prop is giving the same thrust but requiring only 2200 Watts to obtain 0.164 oz/Watt.

This is what I've been noticing about all the gearless (outrunner) setups that I've investigated, and owned. They require considerably more input power to achieve the same usable flight power (thrust).

I like the oz/Watt benchmark. Good idea. That captures it well.

I've had plenty of problems with geared setups, but they still appear to me to be by far more efficient, as well as lighter weight.

More input power means more battery, which means more weight, on top of the already heavier motor.

[desert_flyer]

DF,

The 1915/3Y comes close to the top end performance of the 1515/3D: on 10S the maxumum rpm are several percent lower giving less thrust on up-lines and less punch out power from a hover. For typical flying the 1915 will be about 85-90% efficient while the 1515/3d will be about 95% efficient. So to get the same total lfight time you would need batteries with 5-10% more capacity (and weight). The 1915 weighs 14.5 oz while the 1515/3D with gearbox and finned case is right at 20 oz. So, for the same total weight the 1515/3D has several percent more top end power.

Randy,

What do you mean by "same total weight" if the 1915 is 5oz lighter?

I think this combo would work well with my EVOLITE 5350's and i would save another 5oz, which brings me close to 10lb AUW!! I already have more flight time than I need anyway.

[SD_Raptor]

Randy,

What do you mean by "same total weight" if the 1915 is 5oz lighter?

I think this combo would work well with my EVOLITE 5350's and i would save another 5oz, which brings me close to 10lb AUW!! I already have more flight time than I need anyway.


DF,

I was speaking in general. For any given pack size with the 1515, one would need a pack about 10% larger to get the same flying time with the 1915, depending on flying style. If youalready have reliable high capacity packs that provide more flight time thatn you desire, then the 1915 is a good option.

Where do you get the Evolites? I'll get a set to try as well.

Randy

[desert_flyer]

Randy,

Tower Hobbies has the 5350mAh 5 cell packs for $250 each. There is usually a $30 discount if you spend >300, just check the front page for the coupon code.

They have worked well for me on another 11lb plane. I have about twenty cycles on an FMA charger at 2C. When I bought them I was suspicious about their ability to hold voltage but they seem to be underrated if anything. If I had known this, I would have gone for the 4200mAh packs and saved even more weight. Still, the CG might be difficult to attain with the YAK, because I have no receiver pack.

Anyway, the 5350s provide 14 mins of aerobatics on my biplane, starting with a 90% charge and leaving around 20% capacity. This is a hyperion outrunner drawing 2400 watts max. You should get close to 20 mins with the Neu. Personally, that is too much for me. Still, I expect battery life will be good because they'll never get drained and the maximum draw is only 15C.

Because of the CG issue, I will stick with the 1515. I'm also worried that the plane wont snap well if it is too light. I'm sure the OP would agree with me on that one :D

[SD_Raptor]

DF,

Have you weighed your 5350's on a reasonably accurate scale? In a couple of other discussion groups, there seems to be some controversy about whether the 5S 5350 Evolite actually weighs 500g or closer to 575-600 grams.

Thanks for the info that Tower carries these batteries!

Randy

[Jocke]

The never ending story on rc groups ;) DD/outrunner vs /geared.

[desert_flyer]

Randy,

Mine are 19 oz with the connectors.

DF

[SD_Raptor]

DF,

Thanks! The various websites selling or giving specs all list tthe 5350 5S at 500 grams rather than your value of 590 grams - a 90 gram difference is 3 oz per pack or 6 oz for a 10S lashup.

Randy

[F1 Rocket]

DF,

Thanks! The various websites selling or giving specs all list tthe 5350 5S at 500 grams rather than your value of 590 grams - a 90 gram difference is 3 oz per pack or 6 oz for a 10S lashup.

Randy


Wouldn't that be 541 ish grams for 19 oz?

[SD_Raptor]

Wouldn't that be 541 ish grams for 19 oz?

F1, quite right! Cheap ass computer at work :D

Now the Evolites looks even more attractive.

[desert_flyer]

Randy,

I am sure that the 4200mAh packs will provide enough juice, if you're looking to lose weight rather than obtain an increase in flight time. Assuming they hold 35V under 17C load (which is less than my 5350 packs), the 17C draw would provide 2500 watts.

How is your CG with the 3700s - i.e. are the batteries right up against the firewall?

I just installed the graphtech LG - at least an inch taller than stock and the plane seems to be sitting rather nose high!

[SD_Raptor]

DF,

on my Graphtech gear, I cut the wheel end of the legs back a bit and drilled the axle holes to keep the cowl at the same height.

I have plenty of room to adjust batts since I have the receiver pack up on the motor mount.

I think I would prefer gaining flying time if I can keep at the same weight and battery performance. Then I could practice longer as I begin trying to learn the IMAC Sportsman sequence.

[desert_flyer]

Thanks for the info - I hate having to cut or drill CF. Im still itching from Mondays efforts.

BTW: have you compared the Mejzlic E and WE props for draw, efficiency etc. I elected to use the 1515-2Y motor and 6.7:1 gearbox so i would have more prop diameter to grab the thin air here. Luckily, Mejzlic has the 22x12 prop. P-calc estimates 65A, 2300W draw and 390oz static thrust for an APC of the same diam. & pitch. That should be plenty but what what about the wide version???

[SD_Raptor]

Thanks for the info - I hate having to cut or drill CF. Im still itching from Mondays efforts.

BTW: have you compared the Mejzlic E and WE props for draw, efficiency etc. I elected to use the 1515-2Y motor and 6.7:1 gearbox so i would have more prop diameter to grab the thin air here. Luckily, Mejzlic has the 22x12 prop. P-calc estimates 65A, 2300W draw and 390oz static thrust for an APC of the same diam. & pitch. That should be plenty but what what about the wide version???

The wide will likely draw a few more amps and give about 10% more thrust. It also has the advantage of providing better braking on the downlines. I say get both - either will work and you will have a spare.

[LaxLife]

We maidened our Yak54 today. Just great!
Hacker C50 14XL
Mejzlik 22x8 prop
Jeti 90 ESC
10S 5000 mAh TP Extreme Lipo's
data points collected next time. Today was pure adrenaline!
Hovered at half throttle.

[SD_Raptor]

We maidened our Yak54 today. Just great!
Hacker C50 14XL
Mejzlik 22x8 prop
Jeti 90 ESC
10S 5000 mAh TP Extreme Lipo's
data points collected next time. Today was pure adrenaline!
Hovered at half throttle.

Congrats! Maiden flight is always a thrill :D

[Team Astro]

Alot to be said and learned for our experiences....
I must say this has been a big learning experience for me especially. I understand why people say lighter is better. If someone would have addressed earlier the affects the weight has on the wing loading, I am sure it would have made sence sooner.
I appoligise to anyone who seemed offened. Im sure it was my own lack of knowledge that made me misunderstand the meaning of the phrase, more than anything...
A good 3-D machine needs a light wingloading, more than outragious power numbers.
Yes, I do agree this is way too much motor for the airframe to be a good 3-d machine. I am quite impressed, none the less, that the airframe has no issues with holding up to this much power, and still does great aerobatics and the blenders are SWEET!!! It almost lands itself, I am shocked... but the wing loading kills the transition into high alpha manuvers. Extreme Flight has a light and strong airframe for sure, so Wieght Watchers here I come....
The ultimate goal for me was to build a larger 3-D plane, that would fly more like a foamie than a brick, so try, try again...
I failed in my first attempt using the 8120, so sounds like I need a new set-up....
Just so happens Steve and I demoed the new Astro 60 GM in his 17 pound cub at NEAT. He not only flew a this thing in 20mph+ winds, he did rolling circles and knife-edged it daily from one end of the feild to the other.

Heres the Friday demos in this thread by R/C Groups
http://www.rcgroups.com/forums/showthread.php?t=743388

Bob tested the system in-house with 38 volts and a 22x10 apc-e with 5700 rpm result.

Heres the specs on the 20x10 apc-e
Full power
38v @ 52.7 amps = 2003 watts
Apc-E 20x10 @ 6500
WOW!!! The numbers just don't seem to add up, but these are accual tests we ran with the Nue 10s 4900 packs during the first few cycles...
Partial Throtle Tests
RPM WATTS
6000 1550
5500 1140
5000 875
4500 600
4000 450
*
I plan to drop to a 10s 3650 lipoly, bec's, a berg, HV 85 and the 860GM. I might swap a few servos since my equiptment deffinately overkill, its a couple of ounces!!! Our guess is a weight savings of 2- 2 1/2 pounds. This should bring the wing loading to the 25-26oz range instead of the 31+oz I am at now.

So for now, Im waiting on a 860GM. I do thank everyone and appreciate their opinions. Again, Im off with other hair-brained planes and ideas, some work, some dont, some get re-worked, but one good thing comes form it all, I learned something new everytime...
Terry
Team Astro