The King, 75, was spotted boarding a plane with Queen Camilla, 76, at Aberdeen Airport this morning. He returns to London ahead of a visit to a cancer treatment centre on Tuesday.
The drone was being flown at more than 36 times the legal height. It is thought the operator was never traced, but if convicted of endangering an aircraft they could have been jailed for five years.
Paveway IV bombs have been used to great effect by the RAF since 2008, and were the primary weapon of choice to hit Houthi targets in Yemen earlier this year
Air Vice-Marshal Sean Bell, who served 32 years in the RAF, said Russia was no longer the threat it once was after two years of war, which has seen its forces battered by Ukraine.