Pilot RC Extra 260 vs 300

[nate428]

	Quote: Originally Posted by Scags
	Only problem I'm having with the 300 is the wings rock in harriers. I'm going to start playing around with spoilerons to see if that helps. anyone have any suggestions how to solve it? It calmed down when i went from a 27B to a 28A. I've taken the 28A off and put a JXF 28x8 P tip to see if it helps any. Any help would be appreciated.

the bigger prop kinda makes sense, it would put more air over the control surfaces so they can steer the plane straight...

i couldn't find a thread with all the info, so i will just brain dump what i do.
causes of wing rock = non-lateral balance and a non-centered rudder.
either one of those problems will induce wing rock. forward/aft cg is important but i don't worry about it as much, i just get that cg to need very little down elev to maintain inverted flight.
also most planes like to be in either low alpha or high alpha.
low alpha the harrier is mostly flying off the wings, high alpha its mostly off prop.
to fly straight and true with a straight rudder you may need to correct the thrust angle or use flight mixes, i prefer thrust angle correction.
use this to make sure your plane is trimmed correctly for flight.
http://www.rcaerobats.net/trim_chart.htm
also another way to test the lateral balance besides whats shown in the trim chart, is to do several hard inside and outside loops on a dead calm day... the wing that drops first is the heavy wing.

after all this at least when you do a harrier without any ale/rudder correction the wing rock should dip the same amount on each wing. it may never be as good as inverted but it will be alot more manageable. the aj slick is the only plane i've flown that will settle into a harrier with no wing rock after 1-2 corrections, simply an amazing plane!

[Scags]

i can pull out of a dive into an elevator and neither wing drops and the plane elevators down with out rocking but soon as i transfer from an elevator to harrier wings start to rock. My rudder has a small amount of trim added i will take that out and try that.

Never heard of low alpha can you show me an example?

[nate428]

hmmm, imagine the plane at a lower angle. low alpha around 10-15 degrees, it almost looks like the plane is flying level but real slow. and high alpha the plane is around 50-60 degrees. low alpha will have to carry more forward speed as its flying off the wings more than prop. the idea is that air coming off the wings can create a turbulent air flow to the tail, which destabilizes the plane. you may have heard people say you have to find the right alpha or angle for your plane to harrier? this means that depending on your planes design, certain angles will deflect more turbulent air to the tail and some angles will create alot less. these angles with less turbulence are your best chance of a wing rock free harrier.




here is a video i found searching for harriers, the best i could find quickly that kinda shows low alpha harrier. he is using them alot as falling elevator/harrier in this video. around time 1:50 he's basicly doing low alpha.

YouTube - Broadcast Yourself.

[dstuklek]

If Have anyone maybe extra 300 88" with white-blue scheme?? i can't find pictures of this scheme