Friday, April 2, 2010 at 10:58PM

The Convair B-58 originally went into service in 1960 with standard ejection seats, but the possibility of ejecting at supersonic speeds and at extreme high altitude meant the crewman stood little chance of surviving these extreme conditions. To deal with this situation, Convair worked with the Stanley Aircraft Corporation to develop an escape capsule. The capsule is shown in the pic above, and it was an extremely interesting piece of equipment that actually closed clamshell doors over the crewman and then pressurized the capsule before ejecting out of the aircraft.

The first live, inflight supersonic test of the escape capsule took place on March 21, 1962, but the body inside wasn't a member of the Air Force… it was a female bear name Yogi! That's her in the photo above. The bear most accurately represented the weight of a pilot, so they drugged her up, strapped her in, and then ejected her out of a B-58 at 35,000 and at a speed of 870 mph. 7 minutes and 49 seconds later, Yogi touched down under parachute, still inside the capsule doing just fine. The Stanley escape capsule had proved to work great in protecting against the high wind blast, the extreme cold and the low air pressure. About 2 weeks later another bear named Big John was ejected at 45,000 and at a speed over 1,000 mph! Once again the capsule worked great and the bear reached the ground unharmed.

This picture shows a B-58 ejection 'test sled' was used in the late 50’s and early 60’s. It was mounted on a 4.1 mile track and used for early high speed ejection testing. Shown here is an original style ejection seat just leaving the sled with a ‘dummy’ in the seat.

Another ejection test shown in this picture using an actual B-58, but this time it’s one of the Stanley escape capsules. In late 1962 they began retrofitting the B-58’s with the capsules. All 3 crew locations were upgraded, but only the pilot’s capsule had a window in it as seen in the top pic. It was possible to start the process by closing the clamshell doors and pressurizing the capsule while remaining in the aircraft. The pilot was able to continue to fly the aircraft from inside the closed capsule. This was useful in the event of a cockpit decompression or if smoke filled the cockpit. If the full ejection was selected, the hatch would be jettisoned and then the seat rocket fired and sent the capsule on its way.

The capsules were designed to protection even after landing. They included a variety of onboard survival gear and were also built to float. Most important, the tests done with the bears proved that the system worked… in fact the Stanley ejection capsules had a working range of ground level at 120 knots all the way up to 70,000 feet and Mach 2.2.

This picture gives a great view of the crew arrangement on the Convair B-58. Pilot up front, bombardier/navigator in the middle, and the DSO (Defensive Systems Operator) in the back.

I’ve got a couple more ‘B-58 Week’ posts to put up tomorrow as this special segment comes to an end… for now : )