Hello all,

I am new to RC planes, and hope to get some start-up help from you. I recently bought a second-hand JP Prangster kit, which is an EPP foam trainer. Together with it, I got most of the things I need to build it and get it in the air, I think. This includes a used SC .61 glow engine. In the Prangster instruction manual, it says "we suggest that beginners use a .25 or .32 cu. ins. engine. The more experienced pilot can fit larger engines up to .40 cu. ins. for fully acrobatic performance...", and "up to .53 cu. ins. can be used by expert flyers". This makes me a bit uncertain about my .61 engine. What will happen if I try to use this engine? Will I be able to fly if I balance the plane with some metal in the tail-part to get the proper centre of gravity, and don't use full throttle range, or is this a bad idea? This is my first plane, and I have no experience with flying RC planes.

Also, it seems that channel 2 on the receiver, which is for the elevator, provides the servo with less power than for instance the rudder channel. The servo does not turn as much as the others. I have tried switching servos, and so eliminated the possibility of the problem being the servo itself. The channel 2 servo also vibrates a little when I push the rudder stick on the transmitter. Do you have any suggestions to this problem, other than buying a new receiver?

Thank you in advance.

Don't try and fly alone go to your local field and get some help

Why "uncertain"? Your .61 is twice the size of the recommended engine for beginners. There is nothing ambiguous about it...you have the wrong engine for this plane.

As to the elevator control, your second hand radio is probably a computer radio, and it may have been programmed by the previous owner. You need to use the manual and clear the memory for the model and get some help setting up your radio. It is very common to set it up for more rudder movement than elevator. Some coupling could be in there too.

As above, don't try to do this on your own.

Thanks for the replies. I'll find some experienced pilots and ask for help, and get a smaller engine for the plane.

Good luck with it, it's a great hobby and worth it to get off to a good start.

Jim

Jitters usually mean bad potentiometers, which means radios or servos that are worn out or corroded from sitting. So you probably have a radio and servo purchase in your near future as well.

Good point that the jitters may be an equipment problem, but I think it's most likely it is just a servo. Just try switching the servo to other channels. If the problem follows the servo, then toss the servo and get a new one. If a servo that is behaving well on another channel starts jittering when switched to channel 2, then it must be the receiver...but I've never had that happen. I have had servos go bad many times. However, when servos go bad the throw does not diminish, instead it may become jittery or even erratic or fail to center consistently; the difference in throw is very likely in the programming. Even jitters can come from programming when coupling is programmed in, but I agree with the post above that it is likely an equipment problem. Find out what it is, don't just replace the radio unless you have other reasons for replacing it.