Lightning Strikes
Joined: Jul 2002
Aviation Qualifications: ATPL(H)
Posts: 3,052
Likes: 56
From: UK
Do you know how a Van De Graaff generator works?
Now imagine the twin discs (main rotor and tail rotor) of a helicopter going into a cloud of positively charged particles.
If you get the correct mix of conditions, then BANG! Followed by several pairs of brown pants. Subsequently followed by a bill of hundreds of thousands for lots of very expensive components that will need to be changed.
Which is why the Met Office is now trialling a system that shows offshore pilots areas where the 'triggered lightning risk' is greatest: http://www.oilandgasuk.co.uk/downloadabledocs/1227/6
Now imagine the twin discs (main rotor and tail rotor) of a helicopter going into a cloud of positively charged particles.
If you get the correct mix of conditions, then BANG! Followed by several pairs of brown pants. Subsequently followed by a bill of hundreds of thousands for lots of very expensive components that will need to be changed.
Which is why the Met Office is now trialling a system that shows offshore pilots areas where the 'triggered lightning risk' is greatest: http://www.oilandgasuk.co.uk/downloadabledocs/1227/6
Joined: Dec 1999
Posts: 2,584
Likes: 0
From: UK
Maybe because a plane can glide, but a helicopter can't
Lightning passing between the rotor system and the structure of the helo must necessarily pass through the gearbox. This can result in a momentary spot weld occurring between meshing teeth in the gearbox which is of course instantly pulled apart as the gears rotate thus leaving damage to the meshing faces of the teeth. Equals strip and rebuild gearbox - expensive.
Otherwise plastic rotor blades (main or tail) can be physically damaged by lightning thus potentially causing an immediate hazard to flight in a way that would not happen if the flying surfaces of a f/w were damaged.
Last edited by Agaricus bisporus; 19th April 2013 at 17:40.
Joined: Mar 2007
Posts: 1,017
Likes: 165
From: Hobe Sound, Florida
Lightning
Wyrwb1,
Part 29 and the associated Advisory Circular which provides guidance as to what the lightning protection requirements are and how to test and prove compliance, will probably illuminate where the industry is on the subject. Serious business and has a not insignificant impact on the design engineers work in multiple areas.
Part 29 and the associated Advisory Circular which provides guidance as to what the lightning protection requirements are and how to test and prove compliance, will probably illuminate where the industry is on the subject. Serious business and has a not insignificant impact on the design engineers work in multiple areas.
