SKUA PERFORMANCE

[mike]

G'day,
Spent the last 7 days test flying the Skua and making alot of adjustments, but very satisfied with the performance. Certainly goes faster than my bee and turns very tight...Spin???..well turns over ok but not as fast as I would like it too...CG??...I have had to use 180g to balance to CG point and while flying normally it goes great...but when flying inverted it immediately climbs and you have to compensate for that (which can be hard). I have read that you need to move the CG point forward to compensate for this..(adding more weight to the nose).is this correct???. With 180g already installed it flies great, but does require about 5mm of flaps to fly level. I just think that that measurement would increase if you had to add more weight to be able to fly inverted correctly. Anyway, very satisfied with the performance and will get more experience in flying it as I go...see u at SC on the weekend...

[sean]

Hey Mike, glad to hear your Skua's flying well. My 48" Skua climbed while inverted when the CG was too far aft. It's interesting that you have 5mm up elev, that may be about right, mine has modified elevons. It'd be well worth moving the CG forward to see how you go - move it forward a tiny bit and you should have the ideal CG location, and once you do that it'll feel a bit more stable in pitch too. Move it very slowly, it's quite CG sensitive- use a maybe 20g piece of lead and slowly move it forward until you find the spot where it flies hands-off inverted, or drops slightly (which is how I like it). My Skua also ended up with about 170g of lead in the nose.

To help yaw stablity it's worth taping a piece of coreflute to the back of each of the standard fins - about 40mm wide and the full depth of the fin. Pete did this to a prototype Skua and it really helped its tracking, with no penalty that I could see.

The spin isn't something's it's supposed to do, but mine (and another 48" Skua I've flown) will spin if the elev throw is too high. It's not perfect and you have to coax it into the spin with a bit of aileron prior to entry, but once spinning it'll keep doing so with no aileron input turning quite fast with low airspeed! BTW if the airspeed increases and the turn rate is low then it's a spiral dive rather than a spin. For normal flying I think it's best to set the elev low-rates so you can't enter a spin, and use high-rates just for spinning.

Sean.

[mike]

Great..thanks for your help Steve!!!...

[mike]

ehhh...Sean!!!

[felix]

seen this one fly first hand and she really gets up and moving and looks tops, good job mike! hope that aileron wasn't to much of a pain to fix.
just an idea on your CG and climbing inverted issue was it you who flew my bee after it's chop job and gave me the pointer of having the trim set forward alot more helping the transition to inverted become easier for me? could it be the trim and not the CG?