IFU3
(n.) Interface Unit 3, term used by Tornado GR4 navigators to refer to pilots. Stick monkey, VPSI, Seat to stick interface, Nosegunner
The Aircrew Dictionary (of unacceptable cliche and overused phrases)
(n.) Interface Unit 3, term used by Tornado GR4 navigators to refer to pilots. Stick monkey, VPSI, Seat to stick interface, Nosegunner