Part of the RC Airplane Troubleshooting Center
What I check first: A bounce usually starts before the wheels touch. The airplane may be fast, descending too steeply, being forced onto the runway, or getting an abrupt elevator correction at the wrong time. The first bounce becomes a porpoise when each correction sets up the next impact.
Quick Answer
Use a stabilized approach, keep enough airspeed for control, reduce the descent with a smooth flare, and let the airplane settle rather than forcing it down. Check CG, elevator throw, expo, gear alignment, and damaged or overly springy landing gear if the technique is repeatable but the bounce remains.
What Usually Causes This Problem
| Possible cause | What it looks like | What to do |
|---|---|---|
| Too much touchdown speed | The airplane skips back into the air with plenty of energy | Stabilize earlier and avoid diving at the runway |
| Forced touchdown | Forward elevator plants the gear and springs the airplane back up | Hold the landing attitude and let speed decay |
| Late or abrupt flare | The model balloons, stalls, and drops onto the gear | Begin a smoother flare with adequate runway remaining |
| Sensitive elevator or aft CG | Small stick movement produces large pitch changes | Verify CG and reduce excessive elevator response |
| Landing-gear geometry or spring | The gear rebounds sharply or the model rocks fore and aft | Inspect alignment, attachment, stiffness, wheels, and struts |
| Rough surface or crosswind | A wheel catches or one side touches first | Choose a suitable runway and correct drift before touchdown |
Work Through It in This Order
- Inspect the airplane first. After repeated or hard bounces, check the propeller, gear block, firewall, wheel axles, wing attachment, battery restraint, and control linkages.
- Verify center of gravity and elevator setup. Aft CG and excessive elevator travel make the flare easy to over-control. Use the airplane maker’s range and measured control throws.
- Build a stabilized final. Set the turn, descent, and airspeed early. Chasing altitude and speed in the last few seconds makes a smooth flare unlikely.
- Separate descent control from touchdown. Use throttle and attitude as appropriate for the airplane to manage the approach. Do not dive to reach the runway and then demand an abrupt flare.
- Let it settle. As the airplane enters ground effect, smoothly raise the nose to reduce the descent. Hold the attitude and allow the remaining speed to bleed off.
- Respond correctly to a bounce. For a small bounce, hold a sensible landing attitude and avoid a large push-pull correction. For a large or unstable bounce, add power smoothly and go around.
- Evaluate the gear only after the approach is consistent. If several genuinely stabilized landings produce the same rebound, then investigate gear geometry, strut damping, wheel condition, and runway interaction.
What the Symptom Is Telling You
| What you observe | Where to look next |
|---|---|
| First touchdown is fast and flat | The airplane still has flying speed and may skip. Work on the stabilized approach and flare. |
| Nosewheel touches first | The flare, CG, or elevator response needs attention; nose-gear airplanes can porpoise quickly. |
| Each bounce gets larger | Pilot corrections are feeding the motion. Go around before control margins disappear. |
| Bounce happens only on grass | Small wheels, stiff gear, surface roughness, or a nosewheel digging in may be involved. |
| Airplane balloons before touching | The flare is too abrupt, too early, or the elevator is overly sensitive. |
Change One Thing at a Time
Write down the exact symptom and the conditions that produce it. Make one correction, repeat the same safe ground check or controlled flight test, and compare the result. Changing several settings or parts together may hide the problem without proving what caused it.
Common Mistakes
- Pushing the airplane onto the runway because it floated
- Making full elevator corrections after the first bounce
- Trying to salvage a severe porpoise instead of going around
- Blaming springy gear before fixing an unstable approach
- Moving the CG outside the recommended range to change landing behavior
When to Stop and Get Help
Stop troubleshooting alone when the condition can remove control, start a fire, throw a rotating part, or damage the structure. An experienced pilot, engine operator, club safety officer, or the equipment manufacturer can help you test it without turning the next flight into the experiment.
Before the Return-to-Service Flight
- Repeat the complete control-direction and preflight check.
- Use known-good, fully charged power and receiver batteries.
- Choose calm conditions and a large familiar field.
- Keep a clear landing path and climb to a safe altitude before evaluating the correction.
- Land immediately if the original symptom returns.
Related RC Plane Lab Guides
Compare the broader landing-problem guide, how to land an RC airplane, and center-of-gravity setup. Return to the RC Airplane Troubleshooting Center.
RC Plane Lab provides general educational information. Follow the instructions and limits for your specific airplane and equipment.