Kadet Senior Engine Mount Position
 

HI,

I know the Kadet is technically a trainer, but the firewall is slow slowped down. I want to put somekind of shim so the engine will mount level. I don't have a belt sander to make a nice shim.

How else can I level out the engine mount?

Thanks!

RE: Kadet Senior Engine Mount Position
 

The Kadet requires a LOT of engine downthrust. This is normal, and is used so that at higher throttle settings it doesn't balloon.

RE: Kadet Senior Engine Mount Position
 

Flying with down trust raises the angle of attack on the wing, which will make it climb.

?

RE: Kadet Senior Engine Mount Position
 

You got it backwards dude...

RE: Kadet Senior Engine Mount Position
 

Look, just trust the manufacturer on this one. There is just a very slim chance that they MIGHT know better than you on this one. If you don't like the way it flies, you can always screw it up later.:D They've been marketing this plane for a real long time. If it was broke they would have corrected it by now. SIG is just about the best company in the business.

RE: Kadet Senior Engine Mount Position
 

Here is a pic of the sig senior with no cowl or cheeks, It may be hard to see but that engine is tilted rather far down. But the plane flys
like a dream and and even after my friend and I finished training on it and have moved to other planes, We haven't touched the
setup, and the plane flys every few weeks. I agree with bruce leave it as it was designed. If you still don't like it after flying
for a while add small spacers to the bottom engine mount bolts and try it like that.

RE: Kadet Senior Engine Mount Position
 

Simply use some layers of plywood or hard plastic sheet across the firewall for the engin mount to satisfy yourself.

As explained by others above, that is a bad choice. The Kadet needs down-thrust.

Nay, not so. The angle of attack (AOA) is the free air flow measured against the wing's chord line, not just the prop blast. Notice that a normal flat-bottom wing usually has a rounded leading edge. The center of that LE then sets the chordline which already sets some incidence angle reference the bottom of the wing itself. Given the stab is zero relative the wing bottom, simply by the LE radius, there is some incidence angle set-up.

With a straight engine thrust line, you will have to trim the elevator to maintain straight flight at any gven airspeed. Pull off power, and the machine will dive. Add power and the machine will climb as it seeks to maintain the airspeed that you trimmed for.

Induce downthrust and now when you trim for level flight all is well-- and when you pull the power back, the trim offsets the thrust that was pulling the nose down, thus the machine will tend to maintain the flight line established prior to reducing power. By the same token adding power will create more nose-down against the previously set trim, thus reducing the tendency to climb.

Any flat bottom high-wing will do this. Down-thrust is the answer. The original SIG Kadet was the main trainer of the '70s. SIG did not show downthrust. We had to install it for the newbies. Now that SIG is run by real modelers, I think they understand the basics.

I suggest you go with the aerodynamics rather than the cosmetics. A pilot only needs to know the lift formula that HE can control, which is reduced to Lift = AOA x 1/2 V squared. (Lift = coefficient of lift [AOA] times 1/2 of the air mass density, times velocity- squared, times the wing area.)

Use the downthrust.