Bingo fuel meant that there remained just enough fuel for the aircraft to return to base
In order for this story to make any sense, one must understand what ‘Bingo’ meant. Bingo fuel meant that there remained just enough fuel for the aircraft to return to base and still have enough fuel to make 2 GCA (Ground Controlled Approach) approaches. The fuel required for 2 GCA approaches was 1500 lbs, (about 250 gallons). Fuel management was the Flight Engineer’s most important job in flight. He alone was responsible for the computations. The goal was to have 1500 lbs of fuel remaining in the tanks after we landed and had shut down the engines.
However, that quantity was computed based on losing a recip engine at the moment of ‘Bingo’ being called. The reason for that was because the power increase that was required on the other engines, to maintain level flight, actually used more fuel than if the other engine was still running. This is important to understand and remember.
While flying out of DaNang, we had gone pretty far into Laos. Weight and fuel capacity limited our maximum flying time to 4 hours. The farther we flew from base to target, the less time we could spend ON target. After being on target for the maximum amount of time, I called ‘Bingo’ fuel. We rolled off target and headed home.
After flying toward DaNang for a significant amount time, perhaps around an hour, the Nav was alerted to an urgent need for airpower assistance by some friendly ground forces. When the Nav notified the AC of the call, the AC told the Nav to tell the friendlies that we were ‘bingo fuel’ and that we had to return to base. This situation had no doubt occurred to other flight crews, but to my knowledge the following had never been done.
Once I realized what was transpiring, I quickly recomputed the fuel. Since Bingo is computed as though we had lost an engine, and we were still ‘cooking’ on all four, it didn’t take a genius to realize we had conserved some fuel. The recomputation of fuel revealed that we could spend 23 minutes on another target before getting to another ‘Bingo’ level. That is a lot of reserve and it was only because we had originally ‘Bingoed’ so far from home base. I notified the AC of the reserve we had accrued. There was a short hesitation, then he told the Nav to notify the friendlies that we could spend a few minutes on their target. It normally takes quite a while to get the aircraft on target, enemy identified, and the guns zeroed in. But we did it and spent about 10 minutes blasting away. Then I had to call ‘Bingo’…. a second time.
No one on our crew had ever heard of that being done. The gunners held a friendly grudge against me after that. Why? Because after calling ‘Bingo’ all of the gun bays had to be cleaned up, ammo stored, and brass dumped. After all of that, it was kick-back time for them until we landed. They had to do it TWICE! After that mission they accused me of manufacturing fuel. That exercise put more ‘charlies’ away and let a few more of our guys get home. Had I NOT intervened, and kept my mouth shut, I would have regretted it for the rest of my life.