Revelations into the AV-2 XB-70 accident - 3

Escape Capsules – B-58 vs XB-70

It is now time to consider Mr Burton’s comments about Maj Carl Cross and the Escape Capsules.

Quote: ‘During a debriefing at the EAFB hospital, Al explained that he had encapsulated and was set to eject when he looked over to see that Cross was not properly preparing for ejection. He was pushing on the panel trying to force his seat back into the capsule which was the correct procedure in a B‑58 which Cross had been flying prior to his assignment to the XB‑70A. Al said that he opened his capsule and was trying to show Cross what to do when the ship went out of control. Al had no choice but to eject. However, he did it so fast that he failed to got his right arm back inside the capsule. As a result, his right elbow was injured during ejection. We couldn't believe that Major Cross hadn't learned the ejection process. We went to the seat ejection simulator where all XB‑70A Pilots were supposed to spend so many hours a week (I can't recall how many) practicing seat ejection. According to the log book, Major Cross had initialed the required practice time. However, the simulation crew told us that he never got in the seat ‑ he just came, initialed the log book, and left.’ Unquote.

The inference from Mr Burton is that Major Cross was sufficiently confident that the two escape capsules – as fitted to the B-58 and the XB-70 – were so similar in their design and use that he felt he required no further training. Hence the ‘….the simulation crew told us that he never got in the seat ‑ he just came, initialed the log book, and left…’

So, just how similar WERE they?

First, some background history to put things into context. America's first supersonic bomber, the B-58A Hustler built by Convair in Fort Worth, Texas, posed survivability problem for the crews that flew it if there was a need to eject. Early production and test aircraft were equipped with upward ejection seats, one for each of the crew members.

Side-mounted headrest panels helped hold the crewman's head steady so windblasts would not toss the head about too wildly. Straps attached to hands and feet automatically tightened on ejection to minimize arm and leg flailing. These helped, but were not much protection at Mach 2. More was needed.

The solution to the problem came from Stanley Aviation Company of Denver, Colorado. Stanley and Convair developed the fully enclosed crew capsule, a folding egg-shell-like system to replace conventional ejection seats. The capsules fitted into the standard ejection rails as did the seats. All B-58's ( except the two-pilot TB-58 models used to train and evaluate pilots ) were eventually upgraded with capsules.

The capsules greatly improved both crew safety and comfort. During normal flight the capsule remained open, permitting crew members access to their equipment. Lap, chest and shoulder straps to restrain crewmen during flight were built right into the capsule.

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The capsule was a self-contained survival kit too. It included a host of equipment needed on land or at sea to sustain life and enable crewmen to exist in their compact enclosures. Capsules were fitted with flotation devices, much like small inner tubes, at each of the four corners. It theoretically would float right side up, with the crewman semi-reclined. A snorkle tube permitted air to enter with a ball-valve to keep water out.

Two occasions typically called for enclosing the capsule. In flight the capsule provided a moderately safe cocoon when cabin pressure failed or smoke filled the cockpit, including oxygen mask hookup. The vacuum tube avionics system was prone to overheating and putting smoke and fumes into the cockpit.

The B-58 escape pod

Safe ejection could be expected throughout a wide range of airspeed and altitude conditions. Only extremely high speeds posed ejection risk, or very low speeds at low altitudes. The system was not a zero-zero one permitting safe ejection on the runway.

The primary reason for capsule closure was bailout. The capsule closed downwards quickly when the trigger handles were activated by crewmen. Each independently controlled his own capsule. The closure sequence included automatic restraint and positioning of the user. Shoulder straps tightened and pulled the crewmen back. A bar passing laterally under the legs raised the knees and then pulled heels back against the seat pan. An upright fetal position was needed to assure capsule door clearance.

The pilot's capsule featured a window large enough to permit seeing the primary flight instruments. The flight control stick also fitted within the capsule, enabling limited control of the aircraft. The stick-mounted trim buttons and other switches afforded some control to allow aircraft descent.

A capsule closed in flight could be opened, with some difficulty, if flight was continued and bailout not imminent. Doors could be unlatched with levers located near your toes. Reaching those latches was not easy.

Squeezing the ejection trigger handles caused the overhead canopy to separate from the aircraft, followed quickly by the rocket-fired upward blasted capsule. As soon as the capsule cleared the aircraft, a drogue stabilizing parachute kept the system oriented properly. The main parachute deployed automatically at the appropriate altitude on descent. Normal landing attitude placed the crewman on his back at impact. That helped distribute the shock.

Clearly this is a very different capsule from the one fitted to the XB-70.  Crew restraints were different, the operating and triggering mechanisms were different, and the closure mechanisms was totally different. The B-58 capsule had segments that closed from the top down – the XB-70 device closed with a pair of clamshell doors that came from above and below to meet in the middle.

Therefore it is very strange that, given the complexity of the technology of the escape capsules and the differences in the two designs, nevertheless according to Mr Burton, Major Cross ignored the seat ejection simulator.

I would also ask if this was the case as Burton states, why did the simulation crew let him ‘…never got in the seat ‑ he just came, initialed the log book, and left...?’ Why was this obviously incorrectly followed procedure not reported and stopped?

But that is by no means the last query I have with Mr Burton’s  statements. As I have already mentioned elsewhere in this series of articles, Mr Burton states that ‘…Twice Al was heard telling Joe Walker to “get off my #@*# wing!”’. As I have shown elsewhere, there appears to be no record on any of the surviving transcripts of this having been spoken.  This, however, is not the only problem I have with this statement – I would ask - how did he know that Joe Walker was close to the wing of the XB-70?

Even with the seat in the forward position, lateral sightlines are severely restricted: if the view dead ahead is classed as being at zero degrees, then the view either side of this centerline is 90 degrees in either direction at the very maximum. Given that Al White was sitting in the left hand, or Captains seat position, his view out to the right hand side of the aircraft – where Joe Walker was flying the F-104N - would be even more restricted because he would be looking over and past the copilot and his escape capsule.

I’ve sat on the flight-deck of the surviving XB-70, and it is impossible to see any of the wing structure from either seat, even looking out of the side window on the side you are sitting!

The Captain's seat

So, that is a look in detail at what Mr Burton said just about the XB-70. I have not even considered any of the other aspects he covered in his original piece.

When looked at overall, certainly Mr Burton’s piece raises many more questions than is first appears to answer – although it does seem to raise new information as to what happened.

I am not making out I have any answers to the questions Mr Burton’s piece raises – all I have been able to do, is compare what Mr Burton says with primary source documentation on the XB-70, B-58 and the Accident Report to AV-2.

It’s very tempting to speculate answers to the questions Burton’s piece raises – this I refuse to do. I will say this however, Burton’s piece has the feel of the truth, but without further primary source documentation, I think answers must remain unanswered.