Well....there was a period of time in Iran when we devoted some amount of time tracking down homemade hot air balloons made from survival blankets and sterno cans filled with jet fuel and petrol mix. All were launched at night....and drifted around creating who knows what kind of thoughts in the local's minds!
The MK 93 seemed to be the best configuration for distance and height....if that suggests how much flight time was consumed in the project which was done covertly....after the nightly round of Uckers.