Hi there ,

I have just maiden my new wing with the follwoing set up:

speed wing 400
mega 16/15/4
apc 6x4
hs 81 servos
rx hitech 5 canal

Thw wing is a rocket, amazing!!
However it siffered pretty of glitching, especially when I was gliding to land with motor off. I premise I fly in parck surrounded by buldings. Sistematically, at few feet (maybe 20) from the ground it took strong hits and out of two attempt of landing it went down.
Could you please help me figure what is going on??

it could be a number of things,, you got any picks?.. try moving your antennea around to another spot,, you could be in a glitch prone area,,, did it just rain there?,, i found a place once where i use to fly in a somwhat confined area ,, every time it rained forget it ,, don't even try,,can you post a pick??.."" by the way , have you read that concrusher wing thread?,, pretty nice wing & fast too"""

Yes I have heard about the concrusher, I am about to get one of those!!!!

I just ordered my Concrusher too.

I have that same setup and I might put it into a Stryker. What battery are you using?

I currently have a Mega 16/25/4 with a TP 4S1P spinning a 7x6 prop. It's a rocket but a tad heavy so glide characteristics are so-so. I may put your setup in it next. I like the 16/15/4 because it's light yet delivers similar performance and the bigger 16/25/4 but with less weight and cheaper batteries.

Originally Posted by Pyrock

I just ordered my Concrusher too.

I have that same setup and I might put it into a Stryker. What battery are you using?

I currently have a Mega 16/25/4 with a TP 4S1P spinning a 7x6 prop. It's a rocket but a tad heavy so glide characteristics are so-so. I may put your setup in it next. I like the 16/15/4 because it's light yet delivers similar performance and the bigger 16/25/4 but with less weight and cheaper batteries.

I have a speedwing 400, mega16/15/4, 3skokam 2000, apc 6x4. it goes straight vertical like a dart.

I now have the following setup on my Stryker:

Mega 16/15/4
CC 35 ESC
TP 3S1P 2100
HS81 x2
Aero 6x5 prop
AUW is 21.5 oz.

Weather sucks so no maiden yet but I've seen vids of unlimited vert an stupid fast level passes.

What is the AUW of your Speed 400 with this setup?? Aren't they sub-21 oz.?

are you sure you can run that mega with that prop with that battery???
It seems to me you will be extremely close to the battery amperage limit

Originally Posted by submarco

are you sure you can run that mega with that prop with that battery???
It seems to me you will be extremely close to the battery amperage limit

I dont have Motocalc but I did use the motor calculator at:

http://brantuas.com/ezcalc/dma1.asp

The motor amps says 22.72 amp draw when I entered in the info for the motor, prop, Battery type, and cells. I'm relatively new so you may be right. I also have to consider my altitude of 5000' elevation which would also effect prop resistance. I was going to go with a 6x4 APC prop which many people use but went to a 6x5 to compensate for the MUCH thinner air. Is this compensation legitimate?

Any suggestions or input?

I think your reasoning makes sense. However by considering the kind of goodies you have on your plane If I were you I would still try first a 6x4.
According to this http://www.flyingmodels.org/motortest/index_e.htm, with 8cells-voltage you have 22 amp. expect at least 26 amp with that prop

Originally Posted by submarco

I think your reasoning makes sense. However by considering the kind of goodies you have on your plane If I were you I would still try first a 6x4.
According to this http://www.flyingmodels.org/motortest/index_e.htm, with 8cells-voltage you have 22 amp. expect at least 26 amp with that prop

Thanks...I'll try out the APC 6x4 and after some full throttle runs, I'll put her down and feel the batteries. If they're stone cold, then I'll try out the 6x5's on the next charge. I know my ESC can handle it but I totally forgot the discharge rate of the batteries. I wouldn't want to balloon that $80 pack.

Originally Posted by Pyrock

I also have to consider my altitude of 5000' elevation which would also effect prop resistance. I was going to go with a 6x4 APC prop which many people use but went to a 6x5 to compensate for the MUCH thinner air. Is this compensation legitimate?

Any suggestions or input?

Were are you Pyrock? I too fly at around 5000' here in Reno and more prop for brushed is a nessessity. Many guys here use tamer prop sizes for the brushless setups but either way this is the rules for picking props:

For better thrust (as in thinner air @ 5k feet) use a prop with a larger diameter but the same or lower pitch than the stock prop recomendation.

For higher top speed (in either thin air or lower alt) use a prop with more pitch but about the same diameter.

With these two rules in mind then my advice would be to go with a larger prop but not too crazy on the pitch or you will draw too many amps. Or even worse you may pass the point of diminishing returns with prop aerodynamics and performance. Baised on the prop you are using now I would try a 7x4 or maybe a 7x5 / 7x6 if you need more speed. Most wings in 48" and smaller size that I have seen are using 5" or 6" at the largest so maybe if you recomended prop was a 5" then try the 6x4 or larger then.

-Dave

Originally Posted by Pezzer

Were are you Pyrock? I too fly at around 5000' here in Reno and more prop for brushed is a nessessity. Many guys here use tamer prop sizes for the brushless setups but either way this is the rules for picking props:

For better thrust (as in thinner air @ 5k feet) use a prop with a larger diameter but the same or lower pitch than the stock prop recomendation.

For higher top speed (in either thin air or lower alt) use a prop with more pitch but about the same diameter.

With these two rules in mind then my advice would be to go with a larger prop but not too crazy on the pitch or you will draw too many amps. Or even worse you may pass the point of diminishing returns with prop aerodynamics and performance. Baised on the prop you are using now I would try a 7x4 or maybe a 7x5 / 7x6 if you need more speed. Most wings in 48" and smaller size that I have seen are using 5" or 6" at the largest so maybe if you recomended prop was a 5" then try the 6x4 or larger then.

-Dave

Dave,

Do you fly at Rancho San Rafael Park? Maybe we've met before. Obviously, I'm in Reno too. I have an APC 7x5 and a 7x6 that I used on my 15/25/4 4S1P setup. It was a heavy PIG so I went to my current 16/15/4 3S1P rig. This change was catalyzed by a rather catastrophic crash the other day. (tree ran out in front of my Stryker during a dive). I think I'll start with the Aero 6x5 and monitor the temp after a typical flight like I always do. If it gets too hot, I'll go down to an APC 6x4 that I already have.

Big cause for this is routing the antenna under or really close and parallel to the CF tape/carbon rod. If you did not run the antenna out to the wing tip and past it or threaded in the coreplas wingtip, this may be the problem -- The most critical area being the last 3 inches or so of the antenna. This really needs to be free of such interference causing to work properly.

-Rodger

Pyrock,

Yes I do fly at RSR park but I just started and have only flown there three times. Twice with my Easy Star and once with my instructor's (Phil of course) Devastator on a buddy-box. I have met only a few so far and I can't remember the names. Well I remember John w/ his brushless Slow Stick and Daniel (I think) with a Devastator also. (I let him "try" my 6 cell pack).

I have a Overlord we are starting for my first wing. We shal see how it goes, I may be ready to solo on a wing soon (already loop and get crazy w/ the EZ).

Let me know who you are in PM and we will try to meet up when this weather stops (snow in April, lol).

-Dave

Originally Posted by marjamar

Big cause for this is routing the antenna under or really close and parallel to the CF tape/carbon rod. If you did not run the antenna out to the wing tip and past it or threaded in the coreplas wingtip, this may be the problem -- The most critical area being the last 3 inches or so of the antenna. This really needs to be free of such interference causing to work properly.

-Rodger

Hi Rodger,

I have on the speedwing a hitech 5ch, at 40mhz (here in europe) the antenna is almost 3feet long. I routed all around the half a wing it croses the CF tape maybe a couple of twice and the surface in contact between the antenna and teh cf tape is not more than a 5%.
However ghe last 10 iches goes aside the CF tape, parallel at one inch distance, do yout think it may stil cause inteference?.