Pepsi Wing Checks

Dug out the Pepsi wing to check out alignments, etc. Placing the centre line of the wing on to my CG balancer, the port wing drops own. I then put a weight of 33gms (brass tap handle -all I had to hand) on the starboard wing tip and the wing levelled up. So that needs sorting out by sticking a wheel weight discretely underneath?
Wing incidence next. I don't have an incidence meter (borrow one or could probably make one though) but I do have a pitch-n-yaw app on my phone. With the wing confirmed level by my brickies level I placed my phone on the wing tips in exactly the same positions. Port wing shows +2 deg and starboard -1 deg.

I know this not exactly true aeronautics but trying to discover why the ailerons need so much trim. Albiet the plane flies great anyway.

Comments? Suggestions?

PhilF51 wrote:
Albiet the plane flies great anyway.

Comments? Suggestions?

If it flies great, leave it alone

Ah yes Chris, but if one can reduce the amount of trim required that can be all but a good thing.

On another note I have replaced the 18x10 on the Pepsi with an 18x8 (as per Pennzoil) and hoping this will reduce the initial roll out speed and make landing a bit more controllable.

Phil - Normal practice is to check the lateral balance with the wings attached to the fuselage, you are then
checking out the whole model.
Remove the prop , balance the motor shaft on a straight edge, hold your finger under the tail post, you can the compare
the result of your previous test.
Two people are needed to carry out this test.
Also are there any slight warps in the ailrons which may contribute.
Regards
Colin

It's not that easy to set lateral balance on the workbench as ensuring you are dead on the centre line has a margin of error. The best way is in flight.

Fly upright and trim the ailerons to level, then fly inverted and see if a wing drops, whichever wing does drop is the heavy one. When upright, if say the right hand wing is heavy, left trim will be required to stop it dropping. When inverted the heavy wing and the left trim will work together to create a left roll.

Add weight to the left wing and keep adjusting until the trim is the same both ways up.

Phil, have a look at the amount of lead that is attached to one of the wings on that little propjet Hawk

DaveBright wrote: Phil, have a look at the amount of lead that is attached to one of the wings on that little propjet Hawk

Lead attached? Half a ruddy scrap yard and that doesn't include the tail weights either.:lol:

Tail weight is to counter the overly big engine and throttle pipe on the other end