On Wednesday afternoon, May 8th 2013, helicopter pilot Julia Link landed her aircraft safely on a street in downtown Honolulu, Hawaii, after a sudden and catastrophic engine failure. No-one was seriously injured, although the helicopter was destroyed. Local media hailed her as a heroine, and words such as ‘miraculous’ were used for the landing. But what really happened?
Emergency Helicopter Landing: The Facts
Pilot Julia Link, aged 30, was flying the recently-refurbished R22 helicopter on a photo sortie, along with 71 year old photographer Karl Hedburg. They were overhead Honolulu at 3000 feet when the engine stopped suddenly, with absolutely no warning. Julia immediately put the helicopter into autorotation, in other words, she initiated a non-powered but controlled descent.
She managed to radio the Hawaii Fire Department to warn them of her imminent landing, possibly a crash landing. She then succeeded in bringing the helicopter safely to a halt on Fort Street in central Honolulu, where it skidded and hit a parked car. Mr. Hedburg had to be treated for minor head injuries, but apart from that no-one was hurt.
What is Autorotation?
Autorotation is a controlled non-powered descent of a helicopter. Normally it is the engine which keeps the helicopters rotors turning. However, it is the turning of the rotors themselves which produces lift and actually keeps the helicopter in the air. If the engine fails, something else is needed to rotate the rotors to prevent a crash.
Therefore the pilot needs to initiate a descent, which causes the upflowing air to turn the rotors, much in the manner of a windmill or a falling sycamore leaf. The helicopter will then be descending, usually at around 1000 feet per minute – But it will be under control, and the pilot can steer it to an appropriate landing site.
Decoding Science. One article at a time.