Buying a used RC helicopter

A second-hand helicopter can be a great way into the hobby, or a box of problems someone was glad to get rid of. The difference is usually obvious if you know where to look.

Before you look at it: three questions

1. Can you still get spares? Search for the model's main blades, main gear and tail parts. If nobody stocks them, walk away unless it's very cheap.
2. What radio does it use? A 35MHz crystal set is a sign of an older model; see converting a 35MHz model to 2.4GHz. A BNF model without its radio needs a compatible transmitter.
3. What's included? Transmitter, batteries, charger, manual, spares.

The inspection checklist

Take a small screwdriver, a torch and your phone camera.

Rotor head and blades

• Blades free of cracks, chips and delamination.
• No play in the blade grips when you wiggle them up and down.
• Ball links snap on firmly and move without slop.
• Swashplate moves smoothly, without wobble.

Shafts and gears

• Spin the main shaft slowly with the blades off and watch the top: any wobble means a bent shaft.
• Main gear teeth all present and unworn.
• The rotor should turn freely one way and not the other (the one-way bearing).
• On belt-driven tails, check the belt isn't frayed or missing teeth.

Tail

• Tail blades undamaged, tail pitch slider moves freely.
• Tail motor (on small models) spins freely without grinding.

Frame and landing gear

• No cracks in the frame or canopy mounts.
• Landing skids straight and secure.

Electronics

• Servos centre and move smoothly with no jitter.
• The flybarless unit or gyro is firmly mounted on its pad.
• No burnt smell, discoloured wires or melted connectors.

Batteries

• No swelling. A puffed pack is finished, and isn't safe to charge. See LiPo battery safety.
• Ask how old the packs are and how they were stored.

Ask to see it fly, or at least spool up

With the blades removed (or at a safe distance outdoors), power it up and check every control moves the right way. Listen for grinding or rattles as it spools up. If the seller can hover it, watch for vibration, tail wag and drift.

Cheap faults and expensive faults

The parts that break in crashes, and how to check them, are in after a crash: checks and repairs.

Older models worth having

• Align T-REX 450 and 500 series: plenty of parts still around. See Align.
• Blade models from the last ten years: good UK parts support.
• Recent Goosky and OMPHobby micros.

Older models to be wary of

• Toy coaxials and early fixed pitch models with combined control boards, such as older E-Sky and Walkera models, unless they're nearly free.
• Anything on 35MHz with no conversion plan.

Once you've bought it, give it a full check using the RC helicopter troubleshooting guide before the first flight. What new equivalents cost is in how much does an RC helicopter cost. Back to the RC helicopters hub.