The jumpers down the back had an oxygen console devised back in the 60s using the old regulator but with gaseous oxygen bottles. The LOX system for the crew was not cleared for use above certain altitude so when we ventured higher on JATE we had that aforementioned "octopus" shaped collector box on the flight deck in front of the bunk fed by a gaseous oxygen tank abaft 245.
The "dolls eyes" were monitored by the flight Eng to check that we were all breathing.
For HALO it was OK because we were all connected up but for HAHO the Nav had to go back and brief the team leader on any change of heading before the final climb to altitude. After lot of to ing and fro ing the Loadie finally called that all troops were on oxygen. Well the upper winds had changed so I said, "Just going to brief the team leader" . I trotted down the back with the map and gave the new details, waved to the Loadie who was also masked up, and trotted back a bit slower. You're getting old pal, I thought. As I connected back up the Captain said "you were off before I could say stop. We were going through 18000ft unpressurised. The Loadie said that you looked OK but it gave the troops a start to see you weren't on oxygen" We changed the drills after that.
