Sunday, August 2, 2015

Tragic crash at Russian air show

Four Mil Mi-28 attack helicopters of Russia's Berkuty ("Golden Eagles") aerobatic display team were performing their routine at the Aviamix air show when one of them crashed.  One crew member was killed, but amazingly the other got out with relatively minor injuries (you'll see him stagger out of the wreckage in the latter part of the video). I suggest you watch it in full-screen mode to see all the details.

It looks to me as if the main rotor flexed during the maneuver, impacting the tail rotor and knocking off a couple of its blades.  You can see the damaged tail rotor as the helicopter descends.

May God have mercy on the soul of the dead aviator.  I hope the Golden Eagles and Mil can find out what happened, so they can prevent any recurrence.



Anonymous said...

Peter, I think it more likely that there was a failure of the drive system. Helicopters are designed with the tail rotor beyond the reach of the main blades to prevent the two ever coming into contact. The tail rotor should be spinning at ten times the rpm of the main rotor, instead it is windmilling. There is a drive shaft from the rear of the transmission, supported by several bearings in the tail boom, an angled gearbox, a short shaft upwards and finally the tail rotor gearbox. A failure in any of those components and the pilot has only one choice - autorotate straight ahead. Unfortunately the failure occurred in a vertical climb leaving few options.

The tail rotors of the Hughes Apache, Bell 429 and this Mil helicopter have four blades that have an uneven split between them for noise reduction. It's supposed to look like a squashed X rather than a + sign.


Old NFO said...

Either a combining gearbox or tail rotor shaft failure is what it looks like... Loss of tail rotor authority comes as he pulls up, and you can see the tail rotor is windmilling as he descends... No forward speed to try to do a run on, they were basically screwed as I didn't see an autorotation attempt per se...