Does anyone know if the engine box is supposed to have any down thrust? I hooked my ailerons up backwards and tore out my engine box on takeoff. I wanted to cry, but stiff upper lip and all that.
Any help will be appreciated. Thanks.

An educated guess on my part, I'd say not...

I built this model myself and don't recall any down thrust. There is plenty of right thrust required.

Thanks I didn't think there was any.

Ron,

I did a gas engine installation (FPE 3.2) on my WM 300S, so I was not using the supplied mount. This meant I needed the thrust angles built into the firewall in order to position the FPE. I went to WM and asked them what the as-designed angles were.

The answer was "3 degrees right, 1 degree down". I also queried the designed engine thrust line; it is parallel to, and 28 mm down from, the top of part F20 of the engine box.

Hope I'm not to late... I just haven't been keeping up with the postings the past few days.

Later,
Gary

Thanks alot AV8TOR you weren't to late.

My only big dumb mistake with my 300S so far (I've got a couple dozen flights) was just as stupid as yours, but not as costly. I did a takeoff roll into a heavy crosswind that needed lot's of right rudder. I gave it a lot more than intended, because I forgot to switch back to low rate rudder after the taxi out. With the rudder on high (3D) rate, I ended up doing a 90 degree right turn, nose down, before the plane had rolled 10 feet. Scratch one 44 buck Mejzlik prop.

I really like the airplane... it was my first "big" plane and my first gasser. Aside from the "That's a lot of money sitting on the runway" jitters on the first couple of flights, the transition from .60 size aerobats has been remarkably easy.