Originally Posted by
planemechanic
It's called Speed Tape, and its use as a temporary cover until a permanent repair can be done is perfectly legal and in the Aircraft Maintenance Manual (the AMM). The time that it is allowed to be on there is limited and the repair is probably already completed by now.
I saw this tape used once when a small engine cowling cover fell onto the tarmac just as the plane (a 737) started to push back from the gate. The pilot came on the PA system and explained that there was no saftey issue.