As long as we’re talking about jacks….
Here’s one of 747-100’s on jacks for a retraction check at the Los Angeles maintenance base just before we retired the Whales in 1999. These normally weren’t done outside unless the hangars were full, which was probably the case here. There is a plumb bob and a gauge in the center wheel well to make sure the airplane was level as it went up.
Glad I don’t have to do that anymore!