Scottish Elises

http://www.bbc.co.uk/news/blogs-magazin ... r-30235844

From the article.

The physics relates to something called moments (force x perpendicular distance). It turns out that the passengers - whether they knew it or not - did just the right thing by pushing the wings. Because there was a large distance between the wings and the wheels it gave the people pushing greater leverage. "It's the principle of the spanner - the longer the spanner the less force you have to apply in order to shift the nut," Andrews says. Once the wheels unlocked, the friction would have melted the grease. Then the tow truck took over. So the passengers' version is feasible, he says. But the same probably wouldn't work with a bigger plane. The wings of a Boeing 747 or Airbus would be higher and probably out of reach, he says.

I get this for a turning force. Anyone who has removed a wheel knows this. But the passengers are pushing both wings at the same time so surely this is complete nonsense. Next time my Elise breaks down, I should clearly push it at the edges rather than the middle of the car!

Makes no sense to me - there is nothing pivoting, so leverage is irrelevant surely?

Pushing on one wing at a time to try and rotate the plane, and turn the outside wheel???? Then repeat on other side??

Indeed pushing each wing in turn would work to free the wheels. The photo is unclear, but it looks like they are pushing both wings at once to me.

Bear in mind the frozen wheel is going to pivot on the axel bearing. I suspect this worked because the force applied at the wing was contained both a horizontal and vertical moment, and the resultant vector force applied as a torque around the axel pivot point was suffucuent to release the siezed brake.

Or I could be talking complete bollocks here.

If you have ever read anything in the media that you have actually known about its normally complete rubbish and made up. Probably just stuck to the tarmac and tug was slipping or knackered.

Its not that hard to push a plane of that size, bit of rocking and once it gets going its hard to stop. Bit tricky on snow right enough.