(19)

(11)

EP 0 907 874 A1

(12)

(43) Date of publication: 14.04.1999 Bulletin 1999/15 (21) Application number: 97928379.0 (22) Date of filing: 30.06.1997

(51) International Patent Classification (IPC):  F42B 10/ 50( . ) (86) International application number: PCT/GB1997/001732 (87) International publication number: WO 1998/001719 (15.01.1998 Gazette 1998/02)

(84) Designated Contracting States: GB (30) Priority: 05.07.1996 GB 19960014133 (71) Applicant: THE SECRETARY OF STATE FOR DEFENCE Farnborough, Hampshire GU14 0LX (GB)	(72) Inventor: SIDFORD, Rufus, William-Intellectual Property Dept Hampshire GU14 0LX (GB) (74) Representative: Bowdery, Anthony Oliver, et al  D/IPR (DERA) Formalities, Poplar 2, MoD (PE) Abbey Wood#19, P.O. Box 702 Bristol BS12 7DU Bristol BS12 7DU (GB)