All I can think of is the tail end of an AS.11 / SS.11. This was a French developed anti-tank missile used by UK forces - at least in the AS.11 version.
http://www.rafmuseum.org.uk/cosford/...m?missile_id=1
http://www.astronautix.com/lvs/ss11.htm
http://www.airwar.ru/weapon/aat/as11.html
