Alabama train carrying Shuttle SRB segments derails

Here's one you don't see everyday...

A train carrying reusable solid rocket booster segments for the space shuttle derailed in western Alabama on Wednesday, leaving at least two people injured, a NASA spokeswoman said.

The train was on its way to Kennedy Space Center in Florida from Utah, where the rocket booster segments are manufactured, when the accident happened around 10 a.m. ET near Pennington, Alabama, about 100 miles west of Montgomery.

One of the injured was an employee of ATK, the company that makes the segments, and the other was a railroad employee. The two were airlifted to Mobile, Alabama.

The fuel inside the segments is ammonium perchlorate, which has the consistency of a rubber eraser. Because it is a solid, nothing has spilled out of the railcars.

The train, which had 16 cars, went off the tracks in a forested area after a bridge collapsed. Not all of the cars carrying the eight segments derailed. No residents or nearby communities are at risk, and the fuel cannot explode unless it is deliberately detonated. However, once the fuel is ignited, it cannot be extinguished.

NASA considers the situation stable.

This is the second time this train has derailed on its journey from Utah. On Friday, a few wheels went off the track in Kansas, but no cars turned over. The segments will be sent back to Utah for inspection by the manufacturer.

They had been intended for use in the October 20 launch of the space shuttle Discovery, NASA officials said. The derailment is not expected to affect that launch, because NASA has an ample supply of other segments available.

The fuel inside the segments is ammonium perchlorate, which has the consistency of a rubber eraser. [/color]

Totally crazy,
But hey accident swill happen!

On a side note Ok,
I get fundamental chemistry but untill now I have never actually realised
the solid fuel of the solid fuel rockets was .. am..er.....solid!
(yeah, pretty dense, . me ....not the fuel)

So, is that solid fuel crazy hard to ignite?
Whats the procedure?

NASA considers the situation stable.

Stable in the engineering sense that objects can't fall off the floor?

They thought that when the SRB's were about to be launched in freezing conditions too...

Barberskum, yep thats why they are called solid rocket boosters. Basically they operate like a haloween firework rocket. Once its ignited it burns and all the thrust goes out one end. Thats also the problem with them - once ignited they cannot be extinguished. If something goes wrong the SRB's can be destroyed with onboard explosives.

IThe 'soviet shuttle' Buran used the Energia rocket as its launch vehicle. The 'booster rockets' for Energia by contrast were liquid based. Check out www.buran-energia.com/ for details.

Before the Shuttle era solid rocket boosters were considered far too dangerous for manned flight.

They have much more thrust than liquid boosters, but if anything goes wrong you cannot switch them off.

Peter.

So, is that solid fuel crazy hard to ignite?
Whats the procedure?

I saw a programme on one of the Discovery stations and it said they use a flame thrower inside the booster to start ignition.

When you see the explosive inferno coming out of those boosters you can be pretty sure that the fuel is NOT "hard to ignite".

Peter.