Who said it took four minutes to fail, and the failure happened in one second after four minutes? The (hypothetical) shot into the engine on take off could hit a secondary system which leads to a chain reaction.
I am only positing a hypothesis which has not been mentioned, but which is realistic, hard to prevent, and which could happen tomorrow even if it didn't today.
An arab moslem jihadist jet sniper is not going to care if the jet kills him on crashing, in fact he would welcome his chance to collect his 72 virgins sooner rather than later.
There are far easier ways to bring down an aircraft than trying to do it with a .50 caliber rifle"
I GRANTED that it would be an easy shot. I granted that it could be done. You posited that I had to prove your hypothesis didn't work. I asked for more information.
As far as spending time shooting a rifle, Gee, I dunno, but maybe the range in my back yard DOESN'T make me a really good shot.
You also stated in an earlier post (And I agreed) that a .50 caliber (or smaller) round passing through an aircraft engine WOULD destroy the engine. Dramatically, catastrophically, and immediately. The only thing I take issue with is that you stated that the engine would be destroyed when shot, but this engine didn't explode until 4 minutes later. So, either, you missed your hypothetical shot, (at the 12 FOOT gong), or you are the luckiest terrorist in the world, what with having that delay damage to the jet engine.
Also, BTW, your posts go nowhere NEAR over my head. It's just impossible to follow so many hypothetical concepts at once.