Short rant.
At the end of the day, it's always the pilots fault. As a current JetBlue pilot told me, a wing could fall off and the accident report will still say they crashed due to the pilot losing control.
But I've been around a blackhawk hovering, and four of them has got to make the area pretty unsuitable.
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The pilot reported that he landed on runway 34. He observed five Blackhawk helicopters hovering information on taxiway Bravo. The airplane had slowed to 10-15 miles per hour as it came abeam thehelicopters. The pilot said that the left side of the airplane encountered a sudden blast of air, and the leftwing lifted. The airplane spun hard to the right, exited the runway into a dirt area, and stopped facing180 degrees in the opposite direction. The left wing tip struck the ground during the excursion, andsustained substantial damage. The pilot attributed the wind gust to the rotorwash from the helicopters.
A Federal Aviation Administration (FAA) inspector determined that there were four helicopters ontaxiway Bravo that were doing engine Health Indicator Test (HIT) checks. They were using 30 percentpower with two engines operating, and 60 percent with one engine operating, which was about 1/2 thepower needed to hover. The inspector used scaled airport construction diagrams to calculate that thedistance from the helicopters to the airplane's location when it passed abeam was about 400 feet.
The FAA Aeronautical Information Manual Section 7-3-7 and Advisory Circular AC 90-23G paragraph10 stated that if a helicopter was in a stationary hover near the surface, the main rotors generateddownwash producing high velocity outwash vortices to a distance of approximately three times thediameter of the rotor. They advised pilots of small aircraft to avoid operating within that distance.The diameter of the Blackhawk's main rotor blades was 53 feet 8 inches; three diameters computed to176 feet.Wind reported at the nearest recording station was 360 degrees at 5 knots.
The distance between the airplane and the helicopterswhen the airplane passed them abeam was calculated to be about 400 ft, which was over six diametersaway; therefore, helicopter rotor wash likely did not contribute to the pilot's loss of directional control.
The National Transportation Safety Board determines the probable cause(s) of this accident to be:The pilot's failure to maintain directional control during the landing roll.
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