Jan, excellent pick an exceptional aircraft even by today's standards. The only negative was its short range due to low fuel capacity as its fuselage was nearly all engines and ducting, thus all available room was adapted to the purpose of holding fuel. The flaps were even used as fuel tanks, and the landing gear retracted outward so that there could be greater tankage inboard. This also meant that drop tanks could not be placed beneath the wing and were mounted on top instead. Eventually a ventral tank was added to the fuselage, so the plane could carry more fuel while being more aerodynamic.
The official ceiling was a secret but recently Brian Carroll, a former RAF Lightning pilot and ex-Lightning Chief Examiner, reported taking an F-53 Lightning up to 87,300 feet (26,600 m) at which level "Earth curvature was visible and the sky was quite dark". In 1984, during a major NATO exercise, Flt Lt Mike Hale intercepted an American U-2 at a height which they had previously considered safe from interception. Records show that Hale climbed to 88,000 ft (26,800 m) in his F3 Lightning. Hale also participated in time-to-height and acceleration trials against F-104 Starfighters from Aalborg. He reports that the Lightnings won all races easily, with the exception of the low level supersonic acceleration, which was a dead-heat.