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Nippon Airline struck by lightning in Osaka
Once in a lifetime for crew, passengers and photographer.
Lightning entered the nose and exited the tail.
What was the peak voltage?
Amazing that the aircraft itself, the people and equipment survived!
Even more amazing that there was someone to film it in real time!
This is in normal time
This is in slow motion
This is a still photo just on initiation of the bolt.
Notice the ground and air bolt feeder strike at the same time.
Answers;
Once in a lifetime?
No A/C are regularly struck by lightning; that's why we design to protect against it.
Peak voltage;
Something in the order of 200 - 300 million volts, but it's not the voltage you need to worry about - it's the current (between 30,000 and 200,00 Amps (30KA - 200KA) luckily it's of short duration - about half a second. (500mS.) The temperature is hotter than the surface of the sun - 30,000K (50,000F)
A/C survival
The A/C survives because (in this particular case - B747) it's made of metal - there is more than enough cross sectional area to handle the current for the short duration involved. It's a completely different matter in A/C constructed primarily with composites. The equipment survives b! ecause it's designed to - the real threat to the equipment is through induced voltage/current due to electromagnetic induction effects - the system doesn't directly pass the lightning. This is mitigated against by cable shielding and grounding etc. There can be sparking in tube systems and fuel tanks due to the voltage/current, but again you can protect against this by good design. The people survive because they're inside a 'Faraday cage' - all the electrical effects pass through the fuselage and never come into contact with the occupants. (Same thing in a car struck by lightning.)
'The nose and tail bolts arrive at the same time':
No they don't - it's the same bol! t - the nose is the entry point and the tail is the exit - The A/C is part of the lightning channel for the duration - in fact the A/C's presence may have initiated the strike.
Obviously there's a lot more to it than this - these are high level answers - but that's the gist of it.
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