mallin wrote:This is in reply to your question from my husband, an ex RAF aircraft engineer.
They are lifted into position using winches and fixed to the wing with great big bolts or pins. These pins are in some cases up to two inches in diameter.... They will not break.
Actually I think the bolts are the weak point designed to allow the engine to break away in certain circumstances. I fly helicopters so not sure if that is just a rumour?
Is it not the position in which they are attached that allows them to flip over the wing to ' safety' ?
Surely the bolts have to be sturdy enough to keep the engine in place at all costs ?
There are different forces that affect a wing so the bolts are designed to hold under X forces but to sheer off if Y force is applied (such as a plane hitting the ground) - the forces are different so the bolts can be designed to act in a particular way depending what forces and stress they are put under.
There are some materials that under certain circumstances are stretchy but in others are rigid.
You can drop a glass on a hard kitchen floor and it doesn't smash but if you knock it on the side of the washing up bowl it does.
Also thinking that with a seat belt if you try and yank it the mechanism siezes up but if you pull it gently it doesn't. You want the latter when putting it on or taking it off normally but the former when the car comes to a sudden stop.
I've probably offended every materials scientist in the world now by this explanation !