siang wrote:I often seen people lifting their plane up when tuning the engine. What are they doing? Do I have to lift up my bench jigs on testing as well?
It's normal (advisable) to lift the nose of the model to vertical when tuning the engine so as to make sure it won't go lean and die when you try to climb.
Because the fuel tank is behind the engine, raising the nose of the model will require the engine to suck fuel against the force of gravity from the tank to the carby.
This will inevitably cause the engine to lean out a little when compared to running with the tank and engine at the same level (as is the case when the model is on the ground). By raising the nose you can check that the needle is set rich enough that the motor wont's stop or start to bog down for lack of fuel.
I've seen plenty of models crash because the owner has tuned the needle for maximum power on the ground (generally quite lean) and not checked to make sure it will keep running when the nose is raised. Those planes go barreling down the runway, the nose points up, they start to climb, then the motor stops and they crash to the ground.
You don't need to do it when running on the bench.
RCModelReviews.com, just the facts.