I read some where that the rotary engines had many a problem. Lots of camel missions would lose 50% or more due to dud engine forcing the pilots to return home. Plus many a new pilot didn't realy know how to adjust the fuel/air correctly when they arrived at the front..(no wonder with so few hours).
Somewhere I have Bletchy's engine failure doc from RB3d days. That was quite a good a mod.