(19)

(11)

EP 0 534 966 A1

(12)

(43) Date of publication: 07.04.1993 Bulletin 1993/14 (21) Application number: 90916336.0 (22) Date of filing: 26.10.1990

(51) International Patent Classification (IPC):  B64D 39/ 00( . ) (86) International application number: PCT/GB1990/001644 (87) International publication number: WO 1991/006471 (16.05.1991 Gazette 1991/11)

(84) Designated Contracting States: GB (30) Priority: 27.10.1989 GB 19890024246 (71) Applicant: GEC-MARCONI LIMITED Stanmore, Middlesex HA7 4LY (GB)	(72) Inventor: RAYMENT, Peter, Anthony Hants PO10 7VJ (GB) (74) Representative: Vaufrouard, John Charles  The GEC Patent Department(Chelmsford Office) GEC-Marconi Research Centre West Hanningfield Road Great Baddow, Essex CM2 8HN Great Baddow, Essex CM2 8HN (GB)