DM-3

Tomorrow (Thursday September 8 ) ATK is scheduled to fire the DM-3 motor, the last of the Shuttle-sized solid rockets. This is a 5-segment motor originally designed for the Ares I and V boosters

Last night (Tuesday) ATK held an “open house” for the public. Apparently this was something like only the third time they’ve done that. And as it turns out, I was the first member of the public to show up… and was followed by less than a  dozen, at least for the hour or so I was there. They had a conference room set up with lots of informational boards… largely revolving about one single topic: the fact that ATK dumping dirt on your dirt is not a danger.

Much to my surprise, after a little while we were bundled onto a bus and driven up to the test stand to wander around the rocket itself. This was something I only got to do once when I actually worked for ATK, and then *not* with a camera. The motor has been heat-soaked to 90 degrees F for a good long while, and this will continue until tomorrow morning sometime, so the building-on-tracks that covers the motor was in place while we wandered around it.

The DM-3 test will in all likelihood be the last time in my lifetime that a single rocket of this power will be fired. The ATK staff had – or at least expressed – high hopes that another one like this will be test fired in 2013 or so; but that decision is contingent upon decisions to be made “very soon.” The DM-3 was being touted as the first stage of the “Liberty” launch vehicle, the International descendent of the Ares I booster, with an upper stage made from a French Ariane V core stage. I expressed disbelief that such a thing would fly, politically, and was told that the specific reason why the French upper stage was chosen was specifically *because* it was “international,” and that they were just trying to go along with Presidential wishes to internationalize things as much as possible. Shrug.

Anyway, I took some photos. As the motor was still in its enclosure, they necessarily had to be squished-up-close photos. Tomorrow, I shall have two cameras and a camcorder going.

The nozzle.

At about the mid-point of the motor, a support structure holds up the motor with a thick kevlar strap. Something like 400,000 pounds of tension. Without this the motor would sag 8 inches.

Looking down the length of the motor from the head end. The aft skirt is just visible.