Helicopter manufacturer tests blade performance by attaching self‐contained data collection system to rotor during flight

Vertical Aviation Technologies has designed a five‐bladed helicopter rotor that makes one‐third less noise than conventional three‐bladed helicopters. To gain FAA approval, Vertical Aviation Technologies had to prove that stresses on the five blades were equal to, or less than, those on a three‐bladed system. The engineers faced the common problem of acquiring data from a rotating object. Rather than using telemetry or slip rings, they attached a SoMat Model 2100 Field Computer System directly to the rotor head. The Model 2100 rotated along with the strain gauges on the blades, collecting data unattended during ten minute test flights. Test results showed that individual blades in a five‐bladed system experienced 40 per cent lower stresses than blades in the three‐bladed system. Substantial reduction in vibration also resulted in changing from a three‐ to a five‐bladed rotor system.