Wednesday, 27 February 2013

Maybe they explained it badly?

You know what I've never understood?

How aeroplanes fly.

I mean, I used to work for the UKs largest manufacturer of Aero engines, and I had it explained to me, in great detail, sometimes with diagrams, by engineering zealots all the time and at the end of it, I just looked at them like the Grumpy Cat meme that is so popular nowadays, shook my head, said 'Nope' and walked off.

I mean, let's examine the facts. Air, the things that aeroplanes swim through, the stuff that surrounds us, is light - it's the stuff that lightness is measured against, things are either 'Lighter than air' or 'heavier than air'. (Although I guess, in fairness, things are also either 'Lighter than an elephant' or 'heavier than an elephant' - but that's not a very popular comparison, well, not in the UK at least, maybe they say it a lot on the Indian subcontinent... But in their local language, perhaps - I don't know.)

Aeroplanes, even what they laughingly call 'light aircraft' are pretty bloody heavy. You wouldn't want one landing on your head. They weigh anything up to five tonnes (Strangely, lighter than an elephant - who'd a thunk it?), and the big fellahs, the Jumbo jet for instance can weigh anything up to four HUNDRED tonnes on takeoff (about fifty-seven elephants if you wanted to willingly flog the analogy to death - Which is something I'd never do, especially not to an elephant ).

So, you've got something the weight of a medium sized zoo, floating in something that weighs effectively nothing - Can't happen, sorry... Just doesn't make sense.

The textbooks say that it's all to do with the speed of the air going over the top of wings travelling faster than the air going underneath the wing, generating low pressure and effectively 'sucking' the plane into the air. You're relying on, what Einstein called I believe 'The Weak Sucky Force' to keep a metal tube full of precious, precious human beings up in the air for hours at a time. (o.O)

If you ask a proper physics type if that would actually work, they look all sort of uncomfortable, fidget in their chair, pick their nails, and then say 'Err... Well.. Kinda.. but no, not really' They'll tell you that it's actually all to do with something called 'Angle of attack', which you can experience yourself if you stick your hand out of a car window when it's travelling at speed. Hold your hand flat, parallel to the ground, and it will just feel a bit windy. If you imagine it's a plane taking off and angle it upwards a bit, the wind will hit your palm and it will lift your hand up, and depending on the speed, and whether there's a lorry coming in the opposite direction - It may well get torn off in a horrificly bloody fashion (If this happens, remember to tell the nice policeman/paramedic that I told you not to do it, but you went ahead and did it anyway).

So, the really scientific types say that the wind 'blows' planes into the air. Shyeeeah, riiiight! Next time you find yourself next to an aeroplane, do me a favour... Blow on it really hard, see if it leaps into the air, in fact, get some of your friends to help you - if you can get it into the air even a little bit, I will buy you all a Yorkie (and Kit-kats for the girls obviously).

Would you trust your life to something that even people who say they understand them can't decide whether they work by sucking or blowing? I know I wouldn't. Does that make me a Luddite? Probably - Does that bother me at all? Not in the slightest.

I would trust aeroplanes a lot more if their wings flapped like a bird's, at least that's a technology that's been perfected over millions of years - And it would look totally cool!


And here's a quick story from the anals of my Engine Manufacturing Company history - I must point out that this happened 'before my time' and is one of those stories that everyone gets told.

Our final assembly building was due to be visited by one of the Royals, and as happens before such an occasion, Special Branch, or whomsoever it was who looked after Royal security at the time, came to site and poked their noses into everything that could have an impact on the visit.

They walked around with one of the management team and had things explained to them, asked intelligent questions and gave instructions about how we should prepare for the visit.

At one point, allegedly, the rozzer walked around the room where almost completed engines were hanging in gantries above the ground, awaiting some small but very important parts being connected to them. He noticed that they were fixed to their frames by just four bolts, and commented that 'I'm glad that that's not how the fix them to the wings!'

The employee looked at the bolts, smiled, and said 'You're right, when they're on the plane they're only held on by three, and they're smaller and designed to snap easily.'

'What?' asked the Five-oh,

'Well, if the engine gets hit by something solid, it'll start to vibrate, the bolt's will snap, the engine will fall away, and the plane keeps flying.'

'And if the bolts don't snap?'

'Well, once the engine starts to vibrate, the wing will start to vibrate, and then it will break apart, and they're full of jet-fuel...'

'Boom?' suggested the Poh-poh, making the expanding explosion handsignal with both hands.

'Aye... Boom!' Said the Engineer, doing the same.

He took a nonchalant step back, whistled nervously, and carried on with his inspection.

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