Tips N' Tricks
For this little Easter Egg all you have to do is go into the file f15key.ini and add this KEY_P=MEET_SMUT to whichever mode that you use in the game.(e.g. casual mode or expert mode) If the P key is already being used in the game just change the P to any other letter that is not being used by the game.
To aviod detection by enemy radar or by enemy aircraft just fly below 500ft. AGL and stay at about that height or below and there is a better chance of not being detected.(Also covered in the Jane's F-15 manual that came with the game)