Pat stated that they recommended that the blades never be exposed to temperatures over 175-degrees F. When I worked in Iran we had air temperatures of 113-degrees F and the ground temperature was 168-degrees F and inside the helicopters it was over 180-degrees F and it fried most of the avionics. Solar radiation is a killer and mechanical devices can soak the heat up so the local temperature (of the mechanical item) was far in excess of the local air temperature. I would assume that the two Oz Robinson’s that exhibited debonding operated in similar temperature extremes.
Lord the manufacturer of elastomeric elements on helicopters stated that if an elastomeric element were exposed to temperatures of 160-degrees F for a total period of one hour in the parts lifetime the part life expectancy (MTBF) would be cut in half.
If solar radiation was the cause of the debonding then the killer has claimed two lives (blades)
