i am flying an ultra sport 40 plus with a saito 72. it has a tendancy to tip to the nose. i want a prop to break easy if the plane gets to far. is it possible to run a wooden prop instead of glass filled composite on a 4 stroke? i have heard that the wooden props are not heavy enough for 4 strokes due to a needed flywheel affect on the engine.

my brother was running a wooden prop on a magnum 91 until he got tired of them breaking. No problems there...

I've flown with wooden props on four strokes without problems. If anything, you might not get it to idle as low with wood, but otherwise you should be fine.

Better bet might be to use the elevator more and prevent those nose overs.
Dennis-

its on a grass field and it'll hit a clump or bump and the up elevator doesnt do any good

bigger wheels is your answer, not a weaker prop. You need to be alble to roll over those humps, not plow through them. If they are that big, you're landing in the wrong place. You'll absolutely HATE changing props every time one of those wooden ones break.

the wooden prop's purpose is to break before i pull out another firewall. btw anyone building the US 40 plus reinforce the firewall. where the top piece that connects to the turtle deck. its a weak point where the firewall can split down due to the fact that the blind nuts go thru the joint weakening it. thats why i want a prop that will break on the off chance that i get the plane to nose forward and dig a prop into the grass. on concrete its not a problem i would have to change a prop anyhow even if i rake a composite prop because then its off balance. bigger wheels would add un-needed weight.

OK,
you asked a question on the beginners forum, and I gave you my opinion. I fly off of grass, and use larger wheels than normal for that purpose. Since going to larger wheels, I've not had a plane nose over due to grass clumps and so on. Good luck with your wooden props. Buy lots of them.

Well what I would do is to stop it from nosing over, Take off the gear and bend the part that sticks into the wing so the gear is bent forward, It sounds like the gear is too close to the CG thus nosing over easy, My US40+ had retracts so I ended up opening up the bays a little and shimming them to lean forward to move the wheels forward when down and it almost never nosed over and I have only flown off grass fields.

Dauntae

Good advise on larger wheels. I've always flown off grass, and we usually suggest a minimum of 2 3/4" to 3" diameter.
Dennis-

its not so much that it noses over i can handle that. its that the plane pulls the firewall out. maybe after i rebuild the firewall itll be stronger but i dont want to risk a nose over pulling the firewall out of the plane. i would normally just bend the gear forward and be done with it.