Clark Lindsey points out that the SpaceX Falcon is making steady progress toward first flight. Among all the other milestones noted, I found this one little bit extremely significant:

Regulators gave them "approval to fly the rocket with only thrust cutoff, rather than explosive termination."... "[This] improves hazardous procedures in transportation, on the launch pad and particularly on recovery of the first stage." This [was] allowed "due to the all liquid fuel configuration and six-fold valve redundancy."

As far as I'm aware, the only previous launch system that received permission to fly without range-safety destruct was the SET-1 launch by the American Rocket Company in 1989. The general philosophy has always been that range safety must be able to not only terminate thrust, but destroy the vehicle, should it go out of control. Rockets have always had such range safety devices, and are unique among all other transportation systems in that regard. No ship, train or plane has had devices on board every trip whose sole purpose is to destroy the vehicle.

If SpaceX has gotten permission to launch without it, with only thrust termination, this may be a first for a liquid-fueled rocket (the American Rocket vehicle was a hybrid, with solid fuel and LOX). The big advantage, as it points out, is that there are now no pyrotechnic (explosive) devices on the vehicle, at least not for that purpose, which eliminates some of the steps in launch processing, and post-launch safing, and reduces one of the hazards associated with ground handling (not to mention greatly enhancing the probability of getting the first stage back, even in the event of a mission failure).

Getting such permission is obviously much more important for a reusable vehicle, which the Falcon first stage is advertised to be. They don't want to have to destroy the vehicle just because it isn't following the prescribed trajectory, if they continue to have control over it, because they want to get it back.

This is a key breakthrough in reducing launch costs. Let's hope that it presages the future.

Nope, DC-X/Clipper Graham didn't have a destruct charge, just a parachute.

That wasn't a launch system, Aleta. It didn't get a launch license, and it didn't have enough impulse to leave the range.

Hi Rand,
For the record here's the full quote from Elon:

"From the regulatory front, there is some good news. We received approval to fly the rocket with only thrust cutoff, rather than explosive termination. This is a really big deal and significantly improves hazardous procedures in transportation, on the launch pad and particularly on recovery of the first stage. Falcon will be the only orbital US launch vehicle to fly with thrust cutoff, which is only possible due to the all liquid fuel configuration and six-fold valve redundancy."

I'm a bit surprised. I would have thought they needed several successful flights before they could convince AST to allow this. Glad they got permission from the start.

- Clark

Yes, I was surprised when I saw that as well. It really is good news, and shows that AST is evolving faster than I thought.

"That wasn't a launch system, Aleta. It didn't get a launch license, and it didn't have enough impulse to leave the range."

Agreed, but it was the first VTO rocket powered vehicle that didn't have a destruct charge on it, and this was a Big Deal at the time. Its safe flights helped blaze the trail that Space-X and others are now following. Hooray and congrats to Space-X! And let's hope the good news continues. :-)

SeaLaunch flies without destruct. The engines are driven hard over to break the vehicle's back if necessary. Also, I don't believe this was an AST decision; AST is not involved in the first flight. I'd guess it was WTR range folks making the call.

The release doesn't really make it clear whether that was the maiden flight only or if it was for permanent launch license. If permanent, and especially when flying east, AST would HAVE to be involved. Amazing what focused congressional interest (caused by relentless pressure from bloggers and jounalists)can do.

-Tom

and,

It would be interesting milestone indeed to see the first orbital launcher that has absolutely no pyrotechnic devices on it. I know that there are now non-pyrotechnic bolts that mimic the functionality of "explosive bolts" with the benefit of testability. As minor as this sounds, a totally non-pyro orbital launch vehicle will be a good step forward towards reusability. I'm really pleased with the progress SpaceX is making.

The other major piece of news I found that was very encouraging is that they've already got several interested customers for their Falcon I and Falcon V launch vehicle (about two or three each IIRC), and some of those may even have a signed contract by the time of the Falcon I's maiden flight. If they pull that off succesfully, they'll likely have 4-6 launches next year, which should put them past cashflow positive for their business--which is also a very good sign.

~Jonathan