Taxying out for 09R at LHR a few years ago, a BA 744 on the south side was going on at length about an engine fault.
Eventually he said:
"We've discussed our problem with the engineers and they have advised us that if we shut down and restart the engine it might cure the problem. Where would be the best place to do this?"
The lady on GMC replied as quick as a flash (and vehemently): "GATWICK!"
YS