BAC Lightning, English Electric


English Electric / BAC Lightning

The layout of the Lightning was unusual: two engines above each other, a sharp-edged nose intake, and 60 degrees wing sweep. The Mach 2+ Lightning was the first supersonic British fighter. It was a good dogfighter, with a speed, acceleration and climb rate that were difficult to match. Armament and fuel capacity were limited, however, and the Lightning found few export orders. 329 built Retired from the RAF in 1988.

Type: Lightning F.6
Country: UK
Function: fighter
Year: 1960
Crew: 1
Engines: 2 * 72.6 kN R.R. Avon 302-C
Wing Span: 10.62 m
Length: 16.84 m
Height: 5.97 m
Wing Area: 42.59 m2
Empty Weight: 12719 kg
Max. Weight: 18900 kg
Speed: 2271 km/h
Ceiling: 26400 m
Range: 2500 km
Armament: 3630 kg


The English Electric Lightning was the first operational British aircraft capable of achieving twice the speed of sound. It was an unusual design with two turbojets mounted one above the other in the fuselage and the cockpit placed on top of the nose intake. Although it was designed primarily as a Mach 2 interceptor to meet incoming Soviet bombers at heights up to 60,000ft, it was later developed for ground attack. The Royal Air Force used this variation in Germany and ground-attack versions were sold to Kuwait and Saudi Arabia

SPECIFICATIONS:
Country: Great Britain
Manufacturer: English Electric/British Aerospace Corp.
Designation: Lightning
Type: Fighter
Service Dates: 1960 to present
Length: 55'-3"
Wingspan: 34'-10"
Height: 19'-7"
Empty Weight: 25,000 lbs
Gross Weight: 42,000 lbs
Maximum Speed: 1,500 mph at 40,000 feet
Maximum Range: 800 miles
Maximum Altitude: 80,000 ft
Number of Crew: 1 (2 in trainer)
Engine Type: Jet
Engine Manufacturer: Rolls-Royce
Engine Designation: Avon x 2
Engine Thrust: 16,360 lbs


History

The prototype, known as the English Electric P.1, was built to satisfy the British Air Ministry's 1947 specification F23/49 and flew for the first time from RAF Boscombe Down on 4 August 1954. This specification followed the cancellation of the Air Ministry's 1942 E.24/43 supersonic research aircraft specification which had resulted in the Miles M.52. The Lightning shared a number of innovations first planned for the Miles M.52 including the shock cone and all-flying tailplane, the latter described by Chuck Yeager as the single most significant contribution to the final success of supersonic flight.

The P.1's designer was W. E. W. Petter, formerly chief designer at Westland Aircraft. The design was controversial and the Short SB5 was built to test wing sweep and tailplane combinations. The original combination were proved correct.

The Lightning was specifically designed as a point defence interceptor - essentially a guided missile-armed, air superiority fighter optimised to defend mainland Britain against incoming bomber attacks. In order to reduce cross sectional area of the fuselage and improve performance, the fuel capacity was highly restricted. It was armed with two 30 mm ADEN cannons and two air-to-air missiles, at first the Fairey Firestreak and later the Hawker Siddeley Red Top.

A unique way of minimising the drag of the twin engine installation was put forward by Petter. This involved stacking the engines vertically (staggered to avoid too much weight aft, with the lower engine forward of the upper), effectively tucking them behind the cockpit, fed from the nose and achieving minimum frontal area. This effectively gave twice the thrust of its contemporaries for an increase in frontal area of only 50%.

Limitations of fuel capacity dominated this aircraft's design as its fuselage was nearly all engines and ducting, and thus could not hold much fuel. Hence all available room was adapted to the purpose of holding fuel. The flaps were even used as fuel tanks, and the landing gear had very narrow tyres that retracted outward so that there could be greater tankage inboard. This also meant that when the addition of drop tanks for greater range was considered, they could not be placed beneath the wing and were mounted on top instead. When the aerodynamic principle of the area rule became standard practice, a ventral tank was added to the fuselage, so the plane could carry more fuel while being more aerodynamic.

The first operational aircraft, a Pre-Production P.1B (XG336), arrived at RAF Coltishall in Norfolk in December 1959. From 1960 the production mark F1 served initially with 74 Squadron. An improved variant the F2 first flew on 11 July 1961 and entered service with 19 Squadron at the end of 1962. The F.3 was first flown on 16 June 1962 and the longer-range F.6 on 16 June 1965. The versions sold to Saudi Arabia were essentially similar to the T.5 and F.6 models in UK service and this final production batch reverted to the classic natural metal external finish which lasted well in the drier Arabian climate.

During the 1960s, as strategic awareness increased and a multitude of alternative fighter designs were developed by Warsaw Pact and NATO members, the Lightning's shortcomings in terms of range and firepower became increasingly apparent. The withdrawal of McDonnell Douglas F-4 Phantoms from Royal Navy service enabled these slower but much longer-ranged aircraft to be added to the RAFs interceptor force alongside those withdrawn from Germany which were being replaced by Sepecat Jaguars in the ground attack role. Later the Tornado F3s also arrived to defend UK airspace. While slower and less agile than the Lightning, the Tornado carries a much larger armament load and much more advanced avionics. Lightnings were slowly phased out of service between 1974 and 1988, although much testing and modification was needed to keep them in air-worthy condition due to the high number of flight hours accumulated.

In their final years of UK service all RAF Lightnings were based at RAF Binbrook in Lincolnshire and many were camouflaged to make them less conspicuous when flying at low level. They tended to defend the Flamborough Head Sector of airspace above the North Sea. These later aircraft were the single seater F.3 and F.6 and the twin seat trainer variant T.5, all constructed by British Aircraft Corporation and distinguished from earlier versions by their flat topped fins. In their last year of service their pilots regularly pushed the aircraft to their limits as they used up the remaining hours of fatigue time. Many Lightnings are conserved in museum collections where they delight visitors with their clean sleek lines, evocative of the high speeds that they once attained.

Performance comparison

The Lightning's speed and climb performance were excellent not just by 1950s or 1960s standards but even compared with modern operational fighters. Its initial rate of climb was 50,000 ft per minute (15 km/min). The Mirage IIIE climbed initially at 30,000 ft/min (9 km/min), the MiG-21 managed 36,090 ft/min (11 km/min), and the Tornado F-3 43,000 ft/min (13 km/min).

The official ceiling was a secret amongst the general public and low security RAF documents simply stated 60,000+ ft (18,000 m), although it was well known within the RAF to be capable of much greater heights. Recently the actual operating ceiling has been made public by the late Brian Carroll, a former RAF Lightning pilot and ex-Lightning Chief Examiner, who reports 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.

Carroll reports in a side-by-side comparison that the F-15C Eagle (which he also flew) that:
Acceleration in both was impressive, you have all seen the Lighting leap away once brakes are released, the Eagle was almost as good, and climb speed was rapidly achieved. Take-off roll is between 2,000 & 3,000 feet [600 to 900 m], depending upon military or maximum afterburner-powered take-off. The Lightning was quicker off the ground, reaching 50 feet [15 m] height in a horizontal distance of 1,630 feet [500 m].
However, later fighters greatly outclassed the Lightning in terms of range, radar and avionics, and weapons load, and were far more effective air-to-air fighters. The short range of the Lightning - just 900 miles - was particularly crippling.

Text : Wikipedia, the free encyclopedia


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