Post by gwiz on May 22, 2010 9:54:25 GMT -4
"Tell me...what would happen if just 1 of those perimeter columns was
thrown at the plane at 500+ mph ?
Would that column bend and break ?
Or would it crush the alu tube construction ? "
I'm honestly not sure. I'm inclined to think that the two equations are not symmetrical but that the beam would deform or even break anyway, given the amount of kinetic energy involved.
Anyone know the answer? This goes way beyond calculating static load and dynamic load of a floor system, which I have to look up anyway.
I've calculated the kinetic energy of the 767 at 400knots as 1.8 gigajoules, equal to .4 tons of TNT, and tried to get the "tosser" to look at the airplane as a tightly grouped plane-shaped shotgun blast rather than a solid object.
Here's a suggestion as to how you could try a simplified calculation:
You need to know the load that the impacting aircraft puts on the column to decide whether the column bends/breaks. This load is at minimum the force required to bring the part of the aircraft halted by the column to a stop. I'm not sure how much of the aircraft would be involved in impacting a single column, but off the top of my head suggest at least a slice of the aircraft three times as wide as the column. For the deceleration, you could split the aircraft slice up lengthways and add the components, ie first component decelerates over half its own length, last component decelerates over the total length of the slice. At a first guess, you're looking at a load some three or four orders of magnitude greater than the weight of the slice. Depending on where on the aircraft you take your slice, say a few thousand tonnes.
I think you'd need quite a column to take such a load.