The US military bought many expired 707s to use for spares in order to keep the KC-135 fleet flying. The plane's centre of gravity moves once the engines are removed. To avoid tail-sitting the horizontal stabiliser is also removed but, curiously, the tailfins beside these a/c don't match - an Olympic 707 tailfin is visible rather than El Al (there is an OAL 707 four deep in the row).