DART Webcast: Pegasus Launch

Tiffany Nail: As you know, the DART will glide into space aboard a Pegasus rocket. For more on the launch vehicle, here's Pegasus program manager Bryan Baldwin.

Bryan Baldwin: My name is Bryan Baldwin. I am the Pegasus program director. I've been with Orbital since 1985, I've been with the Pegasus program since the early days, since the development phase. Pegasus is known as what we call a small satellite launcher. We go up to about a thousand-pound class satellite into low Earth orbit. With the air launch system, it's a very flexible system, we have to date launched in a number of different locations, both on the West Coast and the East Coast, as well as Reagan Test Site in the Kwajalein Islands, as well as the Canary Islands for the government of Spain.

The launch site is dependent upon the inclination that the spacecraft desires, whether it's a sun-synch, equatorial type orbit, that's all determined by the satellite. For west coast launches, those are basically your sun-synch orbits. We decided early on in the program that the air-launch capability provided us some flexibility that wasn't in the ground-launch systems. Again, we have the opportunity, we can go to any location that has a large, say 10,000 foot runway, so we have a lot of flexibility that's not available on many of the ground-launch systems.

The aircraft that we use, the Orbital carrier aircraft -- Stargazer, we call it -- is built by Lockheed. We've made extensive modifications to the aircraft to provide the abilities to mount the Pegasus up under the belly of the aircraft, and the crew of the L-1011 provides that separation ability from the cockpit once the team has decided that we're go for launch. In the early days of the Pegasus, the carrier aircraft of choice was the NASA B-52. The B-52 was serial number 008, which is famous for a number of NASA operations. The first six missions were all launched off the NASA B-52 out of the Dryden Flight Research Facility. After the first six missions or during that time, we decided that we needed some additional capability for Pegasus, so we began an upgrade program where we extended the length of the motors, both first and second stage motors, and then we sort of outgrew the capability of serial number 8 B-52. That's when we decided that we needed to go to the Lockheed L1011.

Pegasus is a solid motor, three-stage rocket that has a liquid optional fourth stage. That fourth stage is being incorporated onto the DART vehicle. Another one of the unique aspects of this mission is that half stage which we use to circularize our orbit is also used for the DART spacecraft for rendezvous operations with the MUBLCOM satellite. The three fins provide a variation from ground-launch vehicles. They provide the aerodynamic control during stage-one burn versus a ground-launch vectorable nozzle. The Delta wing provides lift for us during the ascent phase, and you will not see a wing like this on any ground launch vehicle. Pegasus also has a 22-foot Delta shaped, all-graphite composite wing that provides lift during the ascent phase. You can see there's four attach points on that wing, that's where the L-1011 attaches to the Pegasus prior to drop during the captive-carry portion of the mission.

I think the launch operations always are the most exciting part for me. It's where everything comes together, all the hard work that the folks have put in comes together and you finally see that final product where everything goes well and you're able to do what you said you could do.