Abort Contingencies (9G)

Melvill continued to expand the flight envelope and to test the feather. Figure 7.12 shows him inside the cockpit pulling the feather control. But he had another important task to complete.

All this flight testing was really aimed at one goal: SpaceShipOne flying a spaceflight. So, every step along the way had to accomplish something that would bring that goal just a little bit closer. But this also meant that contingencies had to be worked out. “Probably the biggest fear we had for every flight was having to abort,” Doug Shane said about the rocket-powered flights.

Scaled Composites had very good confidence in how SpaceShipOne flew by this point. And after an extensive rocket-engine test program on the ground, they also had a good feeling about the rocket engine. So, Scaled Composites felt a safety incident was not likely to result from flying SpaceShipOne or firing the rocket engine. But an abort during a test flight was much more plausible, considering one had already occurred.

If SpaceShipOne aborted while full of fuel and oxidizer, then this would be much too much weight for it to handle during landing. “You

Fig. 7.15. The photograph shows Brian Binnie preparing right before his first time flying SpaceShipOne. This would be the last glide flight prior to the start of SpaceShipOne’s rocket – powered test flights. Mojave Aerospace Ventures LLC, photograph by David M. Moore

have to actually dump nitrous to get rid of about 3,000 pounds (1,360 kilograms) of mass. But you couldn’t deal with the rubber in the rocker motor,” Shane said.

For this test flight, Melvill evaluated the emergency handling and landing characteristics. Figure 7.13 shows SpaceShipOne dumping the ballast, which it used to alter the CG during testing. Additional mod­ifications were also made to the landing procedures, and figure 7.14 shows SpaceShipOne’s smooth touchdown.