Pre-Flight checks are just as important for RC airplanes as they are for full scale airplanes. There are uncountable things that could go wrong during a flight. It is critical that you check everything humanly possible to minimize the risk of crashing your airplane.
Below is a list of the most common pre-flight checks with slight differences depending on the type of aircraft that you are flying. If discipline is your guide in performing these checks before each flight, then you could minimize the possibilities of something going wrong. Just remember, anything could go wrong! The key is to expect the unexpected!
Needless to say that the pre-flight checks that are listed below, are the final steps to a series of checks and possible repairs that already have taken place in your workshop before you even transport the aircraft to the flying field.
Fuselage internal check (Before attaching wings)
1. Check that servo mount, servos, and servo arms are secure.
2. Check that pushrods and rudder pull-pull cables are secure.
3. Check that receiver/ers and battery/ies are secure.
4. Check for loose items/wires that could foul servo arms/ pushrods / cables.
1.Check for breaks, warps, cracks, etc.
2. Check aileron pushrods, linkage, clevises and hinges prior to securing wing/s.
3. With your radio system on, make sure the control surfaces are moving correctly with each stick’s movement of the transmitter.
4. Make sure all control surfaces are secured firmly. Sometimes CA hinges can work themselves loose. Make sure all snap links are closed on the control horn clevises. Make sure all the servo horns are firmly attached to the control surfaces. Make sure the screw holding the servo horns to the servos are in place and tight.
1. Check engine mount, engine, muffler, prop nut and/or spinner. Be sure the engine is properly tuned before taking off.
It’s a good idea to hold your airplane (if its size permits) vertically with the nose upward while running your engine at full throttle to make sure it will run when in this position while in the air.
Also make sure you hear the fuel clunk moving freely when shaking the airplane. Some times during a rough landing the fuel clunk can get flung towards the front of the tank and get stuck. This is sure to cause a dead stick landing.
Check propeller for nicks, cracks, etc.
Check nose steering mechanism (if equipped).
Check that cowl is secure (if equipped).
1. Check vertical fin, rudder, hinges and rudder clevis for security.
2. Check tail wheel (if equipped).
3. Check horizontal stabilizer, elevator, hinges and elevator clevis for security.
Battery Voltage Check
Make sure the voltage of the transmitter and receiver batteries are at acceptable levels before flying. Follow the recommendations in the radio manual for minimum charge requirements.
Failure to perform this pre-flight check before every flight could result in a pile of twisted balsa wood!
Range Check/Fight Control Check
A range check is a very important pre-flight check that should be done before the first flight at the flying field. Follow the procedure in your radio’s manual for doing a range check. Some radios require a slightly different procedure than others but all are similar to the following. It’s helpful if someone holds the transmitter for you. Turn on the transmitter, then the receiver.
- While holding the airplane, slowly walk away from the transmitter until the servos begin to twitch violently. With a PCM radio, the servos will stop moving all together. If this distance is greater than 30 m then you are good to go! If it is less than 30 m do NOT fly! You must determine what the problem is and correct it before flying.
- If you are using 72 Mhz leave the antenna (only for the range test) fully collapsed. If 2.4 Ghz is used make sure the radio is in range check mode.
- For computerized transmitters, be sure that the correct model has been selected.
- Check that the flight controls move in the proper direction.
- Check transmitter for correct rates.
- Check that flight control surfaces are in proper trim.
- If you are using a trainer cord that connects transmitters, then repeat steps 4, 5, and 6 for student’s Tx.
- When you are satisfied and before takeoff always double check (if you are using a 72 Mhz radio) to make sure that your antenna is fully extended!