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IMAC trimming question (s)

Welton1720

New to GSN!
You are lucky to get the opportunity to fly with Wayne, I was fortunate enough to fly the Nats in 2003 and the best part for me was getting to Wayne and I'm pretty sure it was his brother? He is a great pilot and even better person, he can certainly get you to the top!
 

tl3

50cc
Always get your cg dialed in first, then thrust adjustments. CG adjustments will impact every other aspect of trimming, consequently, if you set-up mixes to correct pitch or roll coupling, then change your cg, you'll have to go back and re-address the pitch and roll mixes. It becomes quite easy to end up chasing your tail if you don't get things done in the appropriate sequence. Be patient, and make only one change at a time so you can properly evaluate its dividends, or drawbacks.
I think Deryck Taylor will be rather put out that he's been tagged as Wayne's brother... ;)
 
another question for you all!!
this is in regards to the Sportsman sequence. the known,.

on the 1st figure, there is a 2 point roll followed by a Q-loop.
question.
when you fly inverted, do you want the airplane to maintain level, or do you guys like to push to maintain level.

reason i ask, is, it seem my airplane is just a tad bit nose heavy, by 3 clicks of up elevator to maintain level in the upright level flight position. when i turn inverted, i need to push slightly to maintain level inverted. Thus, more work to get that two point roll to look real clean.

in order to get my airplane to be level on inverted flight, i would have to add about 1.5 ounces of weight to the tail.

or

i can go from a 3 blade prop to a 2 blade prop. the three blade props are way heavier than the 2 blade props. maybe by 5 ounces or so. i have these weighed in past.


ok, question number 2??

i have noticed, when doing two of 4 point rolls, that when i am going down at 45 degrees, the first 1/4 roll, in order to maintain a line, immediately after rolling it there, i must apply some rudder correction. Would this be normal and expected?
ok, in addition, i have discovered the same with the 2 of 4 point rolls on a 45 degree climb.

an observation:
if i am doing a 45 degree down (shark tooth) with a 2 of 4, and i roll to the right, my rudder input needs to be in same direction, meaning, right rudder (opposite of doing a knife edge).

ok, if i am climbing at 45 degrees, (as in the goldfish), and i do the 2 of 4 point roll, if i roll to the right, i have to apply left rudder. does this sound correct???
 

tl3

50cc
another question for you all!!
this is in regards to the Sportsman sequence. the known,.

question.
when you fly inverted, do you want the airplane to maintain level, or do you guys like to push to maintain level.

- Most pilots, for precision flight, want the cg slightly forward of neutral. This results in the need for a little bit of negative pressure while inverted. A plane that is balanced at neutral becomes extremely pitch sensitive and as result tends to exhibit rather poor tracking characteristics, among other issues.

ok, question number 2??

i have noticed, when doing two of 4 point rolls, that when i am going down at 45 degrees, the first 1/4 roll, in order to maintain a line, immediately after rolling it there, i must apply some rudder correction. Would this be normal and expected?
ok, in addition, i have discovered the same with the 2 of 4 point rolls on a 45 degree climb.

- Yes. Anytime the plane is rolling, the primary lifting surface is changing from the wings to the fuselage and back to the wings. In very simplified terms, when in a knife edge attitude - even if only briefly - the fuselage side becomes the primary lifting surface and needs to be placed at a positive angle of attack to maintain level flight. In other words, the tail needs to go down, the nose up, the rudder input is commonly referred to as "top rudder" - rudder needs to go up to make the tail go down.
 
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