Darned tootin' they used CANNON FUSE.
Still should be a perfectly legitimate ignition method EVEN AT SANCTIONED EVENTS.

I have yet to see a rocket engine fail to ignite when using cannon fuse.
When I was in the 8th grade back in 1983, my best friend and I showed my 8th grade science teacher this method; he hated the rate at which electric igniters 'fizzled' and failed to ignite motors. When PROPERLY used, I have had a very low igniter failure rate, but for the average 8th grader the fail rate is high and expensive even back then for school programs.
My teacher switched to FUSE for every rocketry class segment until he retired.
We did advise him it was against the mamby-pamby safety code, which he cared about as much as we did...very little.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !