No, service ceiling for the Lightning was the maximum height at which the pilot's survival equipment, including notably emergency oxygen, would enable him to survive depressurisation, oxygen failure or ejection. 'Even without the benefit of full power, the aircraft went to 65,000ft, which was my second 'bust' of the limits that day as the maximum height at which our equipment would keep us alive in the event of a pressurisation failure or canopy loss was 56,000ft.'  Sqn Ldr Clive Rowley MBE, 'Flying the Frightening', FlyPast, March 2006, p60, relating an F2A sortie from Gutersloh in 1976. (His first 'bust' that day was while mock-intercepting his 19 Sqn CO at Mach 1.8: 'The in-service Mach limit for the F2A was M1.7, but we all knew that they had been tested to M2.0.') Hugo Barnacle