Xoar International LLC PJP-T-L 18x6.5 Precision Pair Carbon Fiber

The Xoar PJP-T-L 18x6.5 is a two-blade carbon fibre propeller from Xoar International LLC (USA), supplied as a precision pair for multicopter motors with a low KV rating. It measures 18 in in diameter with a 6.5 in pitch and belongs to the class of mid-sized multicopters.

The 6.5 in pitch is a good third of the diameter: flat, laid out for hovering and efficiency at low rotational speed. The weight of 31 g is the average weight per propeller, with a tolerance of 2 g. The bore is 6 mm. As the recommended upper bound for speed Xoar gives 7,000 rpm; the value is comparable only within this manufacturer. The propeller does not fold. The larger the propeller, the lower the rotational speed has to be at the same blade-tip speed, and the lower the matching KV of the motor.

Multicopters with 18 in propellers fall, depending on take-off mass, into class C2 or C3, and the open category ends at 25 kg take-off mass including payload. Classes C1 to C3 require direct remote ID. In Germany liability insurance is also required for every aircraft, regardless of weight and class. The propeller itself carries no class.

On selection: because the pair is supplied matched, both propellers are replaced together. The hub around the bore carries the highest load, and cracks become visible there first. Frayed edges, nicks at the tip and dull-sounding areas point to delamination and are reasons to replace. At 18 in imbalance clearly loads the motor bearings and the sensors of the flight controller.