IIRC they started all four engines in each aircraft almost simultaneously.
Vulcans did have a 'Mass Rapid' start ability - all four engines at once. But I have an idea it was disabled in the early sixties. Anyone?
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PS. Here we are. From FJJP, Pprune- 5 years ago - less four days.
The combuster start system was a clever system that allowed the engines to be started quickly and without the need for ground equipment (the system was also known as the 'rapid start system') . All you needed to start the Vulcan was a battery with enough power to start the AAPP (Airborne Auxiliary Power Plant - a Rover gas turbine engine in the wing behind the starboard main undercarriage bay) which had a single alternator attached to it to provide AC power for the aircraft.
Once the AAPP was up and running and the electrics on line, the pilot selected rapid start, set the throttle to the 50% position and pressed the start button. A small combustion chamber was fed with high pressure (compressed) air and fuel, ignited and the resulting high speed gas fed into a small turbine, whose shaft was connected to the engine compressor stage via a gearbox and clutch. This wound the engine quickly up to self-sustaining rpm, where the main engine start cycle would continue. The process took about 3-4 secs by which time the engine would be lit and accelerating beyond idle speed. The pilot would then throttle back to re-set the start system, and carry out the after start checks.
That decribes the 'single rapid' start. The 'ripple rapid' start was where the pilot placed all 4 throttles at the 50% position and carried out the above procedure on each engine one after the other (as quickly as it took him to press each start button immediately after each other). This meant that all 4 engines could be up and running and ready for taxy within 7-8 secs.
The 'mass rapid' start was a different kettle of fish, and rarely use after the mid-sixties (and then usually only for special demonstration purposes). Here the whole aircraft was 'cocked', ie switches and levers set in a special way. The settings for the 'ripple rapid' were applied and left like that (usually on QRA). When the crew entered the aircraft, the pilot pressed the 'mass rapid' button. All 4 engines rapid started together, but - and here's the difference - so did all the PFCs (power flying controls). The brakes were released and the ac taxyed immediately, or took off within 2 mins if sitting on the end of the runway in the QRA fingers.
Another part of the system was ability to use low pressure air from the compressor of one engine to start another, known as a 'crossfeed start'. Typically, a pilot would 'rapid start' one engine and use the air from that to start each of the others individually, using 70% power to provide sufficient air volume. However, if he selected 93%, he could start the remaining three engines together.
A fantastic and well thought out system that gave Vulcan crews incredible flexibility to operate independantly.