T38 Talon pusher

[DBlum]

Hey all,This is my first post in the jets area,I must say you guys sure do show some impressive work in here.I thought this might be a better place for this than Parkflyers where I normally hang out. The 8oz airplanes are fun but I decided I needed something that would handle those windy days a little better and this is what I have so far. It's a T38 Talon, 175 sq in,24" span,and 42" length. It will be powered with a direct drive Hacker B20 12L in the tail on a 6cell pack of cp1300s. With any luck I can hand launch this thing without losing some fingers.I'm hoping to come in under 20 oz so the wing loading shouldn't be too bad.It's at 4.2 oz as you see it.I'll post more pics as the project moves along.

[DBlum]

pic 2

[Tomcat Driver]

That is an Extremely good looking aircraft, You have done well, Look forward to seeing it all "Dressed up", Whats you colour scheme going to be??

T.D.

[U812]

As always, you do such beautiful work. Can't wait to see it finished.

Next project, I'd like to see you do an EDF. We'll help you.

Maybe you should try glass.

Here's my latest.

http://www.rcgroups.com/forums/showthread.php?s=&threadid=90721

Steve

[DBlum]

Thanks guys. I know it's probably been done a zillion times but this has always been my favorite aircraft flown by the Thunderbirds. For visibility though the white/day-glo orange is probably better.

Steve,great looking model. I really liked your f-104 also,too bad that bungee ate it. I really like the ducted fans but was never really sure they were the most efficient way to convert electrons to noise:D. Plus I'm not really sure how to work that whole intake/fan/tailpipe area math thing.One of these days.

[monkamarm2000]

Should be a nice setup. And if you keep it light those 6 cells might work better than you would think. I'm finishing up on a tweaked Mirage right now that I re-built the wings( Same profile but thinned) and I am running a B20 15L in it and plane to try it on 8 and 7 Hecell packs. I have run it on 8 CP1300's and a Astro 020 5T but it's way too heavy for the wing and the 020 on 4.75x4.75 prop for comfort. So I redid the plane with little pico servo's and a Hacker. AUW went from 19 oz way down to about 13.5 oz on 8 cells. And the watts stay about the same. Which is promising since it was over 100mph before. So I figure for you worse case scenario you come in at 19 oz and have less wing than I do (delta's are draggy wings) so it should be pretty quik. I would start with a 6x3 prop. You don't get much static thrust on a 4.75x4.75 prop which makes launching a new plane kinda tricky. Then move to a 5x5 and then down from there. Just check your amps, I'm basing this on mine which is a 20amp ESC and a 15L which the amps don't really get above 17.5. I just don't know what the 12L will do on a prop.

Barry

[Steve C]

Looks great :)

Keep posting pictures as you finish it and maybe I'll get motivated enough to finish mine :p

Steve C

[monkamarm2000]

Just a heads up for you Blum. I'm not sure how the 12L will react but, I spooled up my 15L for the first time tonight on a 4.75x4.75 prop on 8 HEcells,Whoa! I was surprised to find that right off the bat the amps went up to 30. I shut it down real fast cause I'm running a 18amp controller. Didn't even think they wold go that high. And since the amps were running that high Hecells don't perform to well after 25 amps so the voltage dropped to 5V in a matter of seconds. Well as luck would have it this is where the voltage cutoff kicks in. After a reacharge and a drop of throttle EPA in the radio down to 42% ? it now runs well at 17 amps and 145 watts. Granted your running CP cells which handle the voltage better. I just wanted to give you a heads up to keep an eye on your ESC. Still I dropped ounces in motor weight over the 020 and have 40 more watts. If you have a watt meter I'd be curious to see what yours comes out at. Or atleast let me know what amps and volts your pulling under load and I can figure the ballpark watts from there


Barry

[DBlum]

Barry,thanks for the heads up. This little 12L is supossed to pull around 30 amps on 6 cells(who flies on 6 cells,thats what you put in your rc car right?). The HE cells would be great but I think all the smoke will leak out of them at 30 amps. This is not my ideal power combo but I had this thing laying around,it seemed a waste not to use it on something.

[DBlum]

A couple of update photos.It's now at 5.2 oz,I think I'll be pretty close to 20 oz AUW. I just need to finish the forward fuselage and carve a canopy plug and it's time to start covering.

[DBlum]

next pic

[Alfredo Rubio]

Why do not you paint your Talon in Thunderbids scheme? Is very nice and beauty with the national colors...:D just for the 50 years...:p

[Thomas Nelson]

Excellent looking bird in real life. And I see you've included the 'pinched waist' just like the real deal. Very Nice! I've had this plane on my PSS to do list for some time.

Just all moving tailerons for control? You'll want to watch these during flaired landings, seeing how they sit flush with the bottom of the fuse. Maybe a place for a 'break-away' design?

Looking forward to hearing and seeing more.

[phoneguy]

The Thunderbird scheme for the T-38 was called the "Stinger" scheme. It was created because the team was now flying the T-38 due to the fact it was the gas crisis and four T-38s were cheaper than one F-4 to operate. Due to the small size of the T-38 people had a hard time spottinmg it. The "Stinger" design won a USAF competition to find the new scheme, it was the easiest to spot and recognize the attitude of the aircraft off in the distance for the crowds.

Just a little history of a great team built around the pride that make this country great.

P.S. You can guess my vote for a high visability scheme. If you need any docs, I believe I have black and white copies of the view of the T-38 from my book on the Thunderbirds email me me at
markjackson34689@cs.com

[DBlum]

Alfredo,I am going to do it in the Thunderbird paint scheme,I just need to see if it flies first before I spend all that time on the graphics.

Thomas,I thought about the tailerons parting company with the airframe on landing so I moved them up some.I just hope it's enough.If not I'm sure they'll "break away " whether by design or not. BTW I love your Flanker,It's been on my list for a long time.It'll be right after my Mig 29 I'm never gonna finish.

Mark,thanks for the info and offer,I'll e-mail you.

[Alfredo Rubio]

:D :D :D Thanks for the little history, I have a book with some color pics with the ´Birds` Talon, if you want I can scan its and send. Good idea about the paint, I remember an series with Mr. Ricardo Montalban " The island of Fantasy" well was the name in Mexico, and in a chapter, an Indian female Doctor, need to control the ancient Thunderbird, and she did it at last.

THE LEGEND REBORN..... and has 50 years old...:D :cool:

[DBlum]

It's starting to look more T38-ish. Just need to pull a canopy and start covering.What do you guys recommend for control surface travel on the tailerons?

[AirX]

That is sweet.... :)

Eric

[U812]

Darn your good. Beautiful!

Steve

[DBlum]

Thanks guys.

Steve,you're pretty darn good yourself!

[flailing]

Not much travel, maybe 1/4" in each direction. It is best if you can get about 3/8" for aileron control and 1/4" for elevator. My guess is it will be pitch sensitive but require more effort to roll.

[Haldor]

Very nice work!

One word for the maiden, "VIDEO" ;)

-Haldor
www.halair.com

[Mike Hall]

WOW dave, thats what i cut out for you? iI sure could not see the parts turning into that.:D Looks great.

Mike

[rogwinger]

Wow! How did I miss this thread. Great looking model.

[JasonJ]

Cut ehh? whats the EDF potential for this bird?

[Alfredo Rubio]

Very scale shape, even the small wings, good for you...

[LongRat]

That's what I was thinking too, nice small wings. Are they scale? Its just that this is very similar to the F-5 pusher I am doing at the moment, with scale wings and I am really unsure about how (if) it will fly. I do not have your level of experience to have got a 'feel' yet.

[DBlum]

Thanks again guys!

Flailing,thanks for the control surface info,sounds like a reasonable starting point.

Haldor,I'll try to get some video if possible.

Mike,those were some funny looking parts weren't they?

Jason,the rear fuselage is 2.5x4.5.I'm not sure what fan would go in there but I'm guessing you would have to enlarge the intakes a bit.

Alfredo and Longrat,I had to have the small wings,it just wouldn't look right without them.The span is scale but I did stretch the chord a bit. With 175 sq in and around 20 oz I'm sure it will fly,I'm just not sure how well.

[Thomas Nelson]

Originally posted by DBlum
...What do you guys recommend for control surface travel on the tailerons?

I've been putting some loose instructions together for my Flanker. Here are the throws I've settled on (all moving stabs):

All throws are measured from the front point of each stabilator.

* Pitch: +/- 11/16”
* Roll: 11/16” and 13/16”. This set up uses Negative Differential. Meaning (for roll inputs) the front of the stabilator raises higher than the opposing stab lowers. This effectively pitches the nose down very slightly when rolling. The net effect is that rolls in the vertical plane do not require pitch correction – just whang the stick over and watch your '27 roll into cloud base.

Just to clarify: Full UP means the front of each stab will be 11/16” lower than neutral. And Full Left mean the front of the left stab will be 11/16” lower than neutral, while the front of the right stab will be 13/16” higher than neutral.

[U812]

Small wings? It's the only way and it will fly fine, I'd bet good money on it.

After the 104 adventure, I wouldn't worry at all.

Steve

[Doc Dyer]

ok I caint stand it any longer.

I have one of the best builders working on a project..
see pic below..

enjoy and try not to drool on the keyboard

[U812]

Doc,

I want it. Very nice. A long road and you almost there. Good on you mate.

I forget, midi or mini??

Steve

[Doc Dyer]

Steve,
as soon as my expert builder gets done with the maiden, Hopefully, my house will be closer to being done, We plan on making a Kit, I have a couple of fuses but as you know that is all they are. It looks kick ass dont it !!!!!!!
the setup is going to be
MF480
Hacker B40-11s
40 amp contoller
12 1300's
sling shot launch.

should go like a bat out of hell......

Bradley

[JANSSENM]

Bradley that looks awesome. I want one too!!! Let us know when they are ready.

jans

[U812]

Sure does.:)

[DBlum]

Thomas,thanks for the info.Sounds like I'm in for a lot of experimentation with this one.

Steve,thanks for the vote of confidence on the little wings.

Doc,don't know how you could stand to keep quiet about yours,that is one awesome looking bird!

Here's a shot of mine with it's new greenhouse.

[LongRat]

Looks amazing! Did you make a wood, or foam plug to pull the canopy over? Indeed is it possible to use foam without it melting? Your canopy and whole frame look fantastic.

[DBlum]

Thanks Longrat. The canopy is stretch formed over a balsa form. If you do a search in the parkflyers section for"stretchforming plastic parts" you should get all the info you need for this process.

[LongRat]

Excellent thread, I'll definitely try that pulling technique. By the looks of it balsa is the favoured plug material.

[lphan]

The Talon's looking great! What scale is it?

lphan

[DBlum]

Thanks lphan. I have no idea what scale it is,I just drew it to have 175 sq inches of wing area. That puts it at a 24in span and 42 in length whatever that scale is. I started covering tonight,here's an updated pic.

[U812]

WOW!!!!!!!!!!!!!!!!!!!!!!! Keep going. Fantastic!

Steve

[therookie]

dblum
are you going to make kits for this wonderful jet?
I would love to have one for me.
thank you.

[Paul Penney]

Dave,

Fabulous job, once again. You can make artwork out of most every aspect of the hobby!

Good luck!

Paul

[FANMAN]

She looks right on Dave!

Excellent craftsmanship sheeting the curves :D

[DBlum]

Thanks alot guys,I'm glad you like it. Sorry rookie,no plans to kit this,it would be quite the amount of work to develop this many little pieces of curved sheeting into a workable kit.

[lphan]

Dear DBlum,

You can call me Le. I checked Talon's dim with the Actual Northrop T-38 Talon. It looks like your model is about 1/12 scale.

Model T-38 Actual T-38

WS: 25 ft 3 in WS: 24 in
Lgth: 46 ft 4.5 in Lgth: 42 in
WA: 170 sq ft WA: 175 sq in

Again, fantastic job, nice covering job too !

Cheers,

Le

[Hawker]

Beautiful! I got to see the Thunderbirds flying T-38's years ago and have loved that plane ever since.

Great job!

[DBlum]

Thanks Hawker!

Le,thanks for working out the scale,I kinda thought it might be somewhere around there.

[Alfredo Rubio]

DBlom, your 38 start to look more pretty, very nice paint work, I can not wait to see your Thunderbird T-38 Talon finish.

Some days ago, I saw a book about the T Birds, When they used the 38, they broke with the tradition to use only first line fighters, but they demostrated wath the advanced jet trainers are good as their fighters, because the 38 was the first advanced trainer with supersonic speeds...:D

[DBlum]

Thanks Alfredo!

Just thought I'd post a quick update,it's just about done. I've been working on the graphics files for the decal shop,they're just printed on paper and taped on to check fitment at the moment. All I'm waiting on is a folding prop and I should be able to give it a whirl,maybe later in the week.

[U812]

You've done it again. Beautiful!!!!!!!!!!!!!

Steve

[gregg f]

very nice!

[stumax]

Nice :) Just 2 things missing - a pair of microfans with Hacker B20's!

Stu.

ps. we're all waiting for some video footage of the maiden flight!

[Thomas Nelson]

VERY very nice!

I am partial to the thunderbird motif - I have it on an old SR-7 slope soarer, which was mildly based on the T-38.

Which folder prop are you trying? The most annoying problem I keep encountering is Broken Motor Mounts ... and a folder would nicely put an end to this.

[monkamarm2000]

Friggin awesome, just outstanding. Did I mention I liked it yet?


Barry

[gbruce]

Dblum

WOW!!

I luv it!


If not a kit then perhaps a plan with the X-sections and basic 3 view (very simple is OK) ...or a free Email to all of us dedicated EZONERS;)

Bruce :)

PS how much washout on your wing tips?

[Tim H.]

WOW! Just beautiful!!!!! Most impressive.

Tim H.

[Alfredo Rubio]

CBlum.... wath can I say....:D :cool: ;) :p very.. very nice and beauty model.

Congratulations.

I wait it fly as good it looks....:)

[DBlum]

Thanks again for the compliments guys,I'm glad you like it.

Stumax,I know what you mean about the fans,the T38 is so slick I hate to muck it up with a silly looking prop on the back.

Thomas,I've decided to skip the direct drive Hacker and go with my trusty B20 12L 4:1 on a 9 cell pack of 950KANs. I've ordered a cam 9x6.5 folder to go on it.I think I'm going to have to machine some blade stops for it though,I believe the spinner usually serves that function.

gbruce,If you can open a CorelDRAW file I can probably whip something up for you,but I gotta warn you what I have looks like an explosion in an airplane factory.You'll have to do a little cyphering to figure them out.BTW I have 1/8 washout in the tips.

[Ed Waldrep]

Oh man that is so fraggin' sweet I'm drooling. A larger version with MF480s and retracts would be awesome.

[JohnVH]

Wow, that is amazing!! I want one!!! Does anyone even make a T38?
Please take more pics and get some video!!!

Here is my buddies Turbine powered one!
http://www.rcsites.net/speedman/jthreequarterfrontt-38.jpg

[Mike Hall]

Dave, how about i cut you another kit and you build it up and make a plug out of it to make Fiberglass fuselages then everyone could have a little bit of your awesome work. im not sure how light you could get a fiberglass fuselage but it sure would not take as much time as what you did here.

Mike

[Doc Dyer]

Mike, check out page 3 of this thread..

[DBlum]

Thanks Ed and John!

Mike,I don't think I have the attention span to look at one airplane long enough to build a plug,make a mold,then make a fuselage.I ready to move on to the next project already! Besides I'm no good with glass.

Doc,yours is looking great!Any more progress pics on it?

[Doc Dyer]

no, sorry,
there should be some more pics soon..

we will all have to wait

Bradley

[David Hogue]

Dave,

I love that!! Takes me back to when pilot made the EZ Talon...always wanted one, but never got ahold of it. Now and then one shows on ebay, but the prices shoot way up on them, usually. I cant wait to see it fly!!

later,
David

[DBlum]

Thanks David,if the planets line up just right I'll test fly it on Sunday,maybe I'll see you out there.Right now I'm building the worlds ugliest takeoff dolly from one of my old RC cars.

[David Hogue]

Dave,

Working this weekend, so seeing me Sunday is pretty much out. Good luck with the testing...if the dolly dont work, I have my bungee and launch ramp!!

[lphan]

Dave,

So how did the flight go?

Anxious,

Le

[DBlum]

Well,first the good news. It flies. Test flew it late this afternoon.The take-off dolly sucked,I think I needed more angle of attack but didn't feel like messing with it. There was either going to be some flying or some crashing,but something needed to happen so I just threw it over the proverbial "tall grass". Climb out was fine,it has enough power to go vertical no problem,roll control was good,no sudden snaps or tip-stall,wing loading is light,and it glides nice. Now the bad news.Pitch control is downright hair raising.It's nose up,it's nose down,who knows where it's going next.I don't feel like it's a CG issue,if anything it's a little nose heavy. First flight it was balanced at 25% MAC,second flight was around 30%. It just "hunts" in pitch constantly which was also a problem in the last really short-coupled plane I did. I'm thinking that the servos are not returning to the same neutral point every time.They're just some old HS55s I had laying around.This is also my first plane with tailerons and I guessed at 20%MAC of the elevators for the pivot point.Is this too much or not enough? Any input would be greatly appreciated.

Dave

[lphan]

Dave,


I had a friend who had a Jepe F-16 with taileron. It's history now. Landing speed are too fast.

If I fly my F-16 just once, I have enought adrenaline high to last me a week ! Yes, tailerons, I avoided them like the plague. That was why I did an all moving right wing and all moving elevator. My second F-16 is about 75% finished; this one has ailerons and and all moving elevator.

I did have a sensitive pitch problem though. I used a the Hitec HS55 also in my F-16. Now, the elevator travel is about 3/16 inch up and 3/16 inch down, and it flies on a rail. The HS55 was able to handle the loading just fine.


I'm glad to hear you didn't crash. On my 6th flight of my first F-16, when testing out the CG, I ended up making the CG too far back, so it weaved up and down like being on an ocean wave. When I managed to pull up, the plane caught a wire on a fence right between the intake and the fuse ! You guessed it, it hung on the wire !

But, I fixed it and flew it again !

So for your beautiful Talon, I would suggest going to ailerons and an all moving elevator.

Again, congrats! You're a great builder !

Le

[lphan]

Dave,

Oops I forgot to ask, what is MAC? For the F-16, I placed the elevator axle at the middle so that the total travel was 3/16 inch up and 3/16 inch down. This is the same for the leading edge and trailing edge of the elevator.

Le

[Bob K]

I noticed that HS 55's did not return all that well when I made a DAW Staudacher. This too, was a short coupled plane. I don't know how you set up your linkage, but, I know this: DO NOT use the transmitter to turn down your control throws. Use as long of an elevator control horn as needed to get the required elevator deflection at 100% servo throw. This is what I did and then the HS55's worked just fine.

Now , as a secondary consideration, considering that you have a full flying stabilizer, IF your control rods/linkage are not really stiff/rigid/zero slop, then , you might consider adding some weight to the leading edges of the stabilizers to balance them. This has not normally been a problem from what I have heard, but, it can be a contributory/second order effect. Work the elevator control horns first.

Bob K

[DBlum]

Thanks Le,I was really torn when I was deciding to put ailerons on it or not,I guess I should have.The trouble is that with the radio I have I can't seem to mix in a lot of surface travel in the roll direction but not much in the pitch direction. BTW,Mac is mean aerodynamic chord.I think I'll retro-fit some ailerons and try it that way.

Bob,The control linkages are slop free but are set up to give a lot of travel for roll. I haven't cut the travel in the transmitter because the servo resolution goes all to hell. I'm gonna bite the bullet and do the ailerons.

[Steve C]

Other than sloppy servos, I don't think the tailerons are causing your problem. It could be a cg issue because of the long fuselage ahead of the wing. Assuming you used flat sheet for the stabs, it could also help to make a thicker set with good airfoil sections on them.

The plane looks great. I hope you get it tamed :)

Steve C

[DBlum]

Thanks Steve,I'm pretty convinced it's sloppy servos combined with way too much travel.I'm gonna chop into the wings tonight and maybe have another go at it this weekend.

[Thomas Nelson]

If you truly DID aerodynamically balance your tailerons, are aerodynamic forces causing first a positive load on your servo, then a negative load, then positive etc? Slow motion flutter?

I've built and flown a couple of open class sailplanes with all moving stabs, and a rule of thumb was NOT to place the pivot EXACTLY on the aerodynamic center.

Further, the servos in the tailerons of my Su-27 are less than perfect at centering too, but I have absolutely no pitch instability.

[Kevin Cox]

Hi,

Great looking model you have there. Your problem sounds like a slightly aft CG, you may want to check you power on and off condition in the air too. Also I would not bother adding mass to balance the stab.....in my opinion it could do more harm than good on our small models. The pivot point at 20% on the MAC is a good location.

If roll is good why bother adding ailerons?

Good look!

[DBlum]

Thanks Thomas and Kevin,you guys certainly have plenty of experience with this setup and I value your opinion. On the CG I have never balanced anything as far forward as 25% and not had it be nose heavy. In flight when the plane pitched up it had your basic nose heavy "mushy" feeling to it,but I suppose it wouldn't hurt to try it further forward. I just re-did my linkages cutting the throws at least in half. I figured it deserved one last chance before I start hacking it up. There is a little flex in the tail surfaces which I'll take out with some carbon fiber to eliminate that as a possibility. Interestingly enough,it did seem to be a little less sensitive at lower flight speeds,I was thinking maybe the elevators were flexing some.I guess I'll see how it works out,whats the worst that could happen?:D I'm ready to move on to the next project anyway.If I can't work it out maybe I'll send it to one of you guys. Thanks again.

Dave

[Kevin Cox]

The aft CG is based on the "pitch hunting". Meaning one second it is levelthen next climbing, then diving....not in necessarily in that order :D If it is just climbing as it flies faster then it sounds nose heavy.

[xcellrc]

Looking good on the high tech mondo funk launch dolly

[xcellrc]

Ok the launch dolly needs further R&D, so lets just hand launch it. I'm not going to throw it....you throw it.....I'm not going to throw it....you throw it.....where do you grab this thing???? Come on how bad could it be? Its just a little geared B20 12L turning a 9x6 prop, I'm sure your fingers will be out of the way in time.

[xcellrc]

Even though you said throw it level, you really meant throw it straight up right??

[DBlum]

Yup,that's about how it went.Thanks for posting the pics Ross,I hope to try the new and improved version Sunday.

[xcellrc]

Need some video here, but this will have to do. Its flying but its up and down, little unstable in pitch.

[David Hogue]

Hey!!!

Who let Ross back in here? Dave, looks good....I want one!! We need to discuss SEFF arrangements, btw!

Later,
David

[xcellrc]

Hmmm, having so much fun on this roller coaster ride, must have lost track of time. Motor cut off so now its time to figure out how to land it. Hey Dave, the short grass/runway is about thirty feet this way!

[xcellrc]

Is this where you meant to land?

[DBlum]

I missed the runway by a bit and landed in the only tiny little patch of hardpacked open area in that whole field of grass,no damage though.Next time I'll put a full charge on the pack.

Gofli, e-mail me about SEFF.I'm going for sure but everyone else is still on the fence.

[DBlum]

Ross,too funny.You're just having a good ol' time with this aren't you?:D

[U812]

What a lot of fun. I had a real good laugh.

The plane looks fantastic!! Especially in the air.

Once you get your little problems fixed you have a keeper.

Now you know it hand launches, forget about the dolly.

Great stuff, really great.

Steve

[xcellrc]

Wish I could be there to see how it goes on Sunday, but I have left the big city, and am back in race city usa where all turns are to the left. Like others, I too thought that the pitch instability was most likely cause by an aft CG. But it definitely is not tail heavy, if anything the CG was forward. The talon exibited no bad stall tendencies with the power off and the nose held high, so I think the CG issue is definitely ruled out. I was thinking the problem was the slop in the servos also. You had the linkages as tight and slop free as is humanly possible with an HS-55 so I don't know how that could be made any better. The thing that puzzles me about that, is that if the hunting was caused by slop in the servos, why then was it perfectly in trim in the roll axis? It seems that it would not have been possible to trim it out in the roll axis if there was a problem with slop, or centering in the servo. The surfaces were hinged far enough forward so that they were aerodynamically convergent, not divergent, so it doesn't seem like the full flying stab would cause problem either. Possibly an issue with thrust angles? That doesn't seem likely either. I think going to ailerons and changing the geometry on the elevators so that you can increase the servo travel, while decreasing the elevator travel will definitely help. Or possibly, you should just abandon the project all together, and I can figure it out for you so you can move on to more important things! :)

[xcellrc]

Me having fun??? Always!!! Hope you get it figured out on Sunday. Perhaps you could find someone with a little extra time on their hands, and an engineering background to help you out. Might help if they had a geared B20-12L, a sub micro flight pack, and some Kan 950's to try in it..... hehehe

[lphan]

Dave,

How does the tailerons handel during landing? Does it come in fast? When do you turn off the motor?

Curious.

Le

P.S. Yes, if you're still having pitch problems, let's have a bid on who get the Talon :)

[lphan]

Dave,

Did you know that since you got the Talon 1/12 scale to fly, you can make an F-104 Starfighter fly?

I've never seen an F-104 electric built with true to scale wings. I always see builders cheating on the wing span and wing area.

Did you know that the F-104 has more wing area than the Talon? The Talon has 170 sq feet : the F-104 has 196 sq feet.

So, after you send me the Talon, you can start on the F-104? :)

Cheers,

Le

[Thomas Nelson]

Originally posted by xcellrc
Possibly an issue with thrust angles? That doesn't seem likely either.

Motor thrust angle on the Flanker is as close to 0,0 as I can get it. My wing is flat bottomed, and I use that as the reference for zero up/down thrust.

However, when I had things misaligned, I definitely noticed pitch to thrust coupling. I take it that your pitch hunting has nothing to do with varying throttle settings ... ?

[DBlum]

Steve,thanks again! Glad we could provide you with some cheap amusement:D.

Ross,I know where you can get some parts if someone with all that free time needs to fill some time.

Le,the plane handles fine during landing.Seems the slower it goes the less trouble.I shut the motor off on final approach and glide in. I wouldn't have guessed that the 104 has more wing than the T38.I did fudge the wing area on mine but not the span,I don't think I could look at it with long wings.Yuk.I'll let you know if I get frustrated enough to give it away:D

Thomas,the thrustline is right at zero.It didn't seem to matter whether I was on the power or off except when I flew it slower it wasn't as bad.

[Alfredo Rubio]

Xcellrc.....very beauty flight pics... congratulations.:D

[DBlum]

Well I just got back from sitting at the field for 5 hrs waiting for the rain to stop so I could try the Talon again. I managed to get 2 flights in and both of those were in the rain. I'm totally stoked,it was worth it! Launches great,flies great,glides great,lands great.After much head scratching the problem turned out to be(here come the I told you sos) you guessed it,aft cg. I swear it didn't feel like it was tail heavy, but then it occured to me that there sure is alot of fuselage forward of the wing that I didn't account for. Turns out the original control surface throws were fine also. Now I can finish this thing and move on to the next project.Thanks to everyone for their input.