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The F-8E(FN) Crusader
From 1964 to 1999, the LTV F-8E(FN) Crusader was the sole interceptor in Aéronavale service. Although it was maintained in service for too long, this aircraft, whose design dates back to the 1950's, was remarkably popular with its pilots. This document does not cover the development of early Crusader variants but only that of the F-8E(FN). 1. Origins and development of the F-8E(FN) Crusader 1.1 Origins In 1962, the French Aéronavale (Naval Air Arm) submitted a request for a new naval fighter to replace its Aquilon aboard the new aircraft carriers, the Foch and Clémenceau. Of the several proposals made by French aircraft manufacturers, none were selected. Dassault proposed a navalized version of its Mirage III, the Mirage IIIM, while Bréguet offered the Br 1120 Sirocco. These very advanced and ambitious projects were deemed too expensive and probably technologically hazardous. The Marine Nationale therefore decided to search for a foreign design. The only two competitors remaining were thus the McDonnell Douglas F-4 Phantom II and the F-8 Crusader, manufactured by the Ling-Temco-Vought (LTV) company. A delegation was sent to the US to determine which of these two aircraft would be best suited to perform aerial protection of the French carrier groups. This delegation included the CC Hurel of the Bureau des Etudes Techniques (Technical Studies Board), M. Faucheux of the Service Technique Aéronautique (Air Technical Service) as well as another engineer. Although the Phantom II was more capable, it was clearly established that it was not suited for operations from French aircraft carriers, which were substantially smaller than American ones. The French delegation therefore turned to the F-8 Crusader. On 16 March 1962, two F-8 of VF-32, based on USS Saratoga, led carrier suitability trials on the Clémenceau, demonstrating that the Crusader could operated off French carriers.
1.2 Development of the F-8E(FN) Following this, LTV offered the Marine Nationale a modified version of the F-8E, specifically designed to operate off French carriers with a lower landing speed.. This version was designated F-8E(FN), standing for French Navy. The reduction of landing speed was made possible through several modifications. The leading edge slats were split lengthwise, which increased their drooping angle to 44°. Flap and aileron droop was also increased to 40°. These modifications substantially increased the camber of the wing in landing configuration, generating more lift and therefore lowering stall speed. A blown flaps system (known as BLC – Boundary Layer Control) was also use. This used air taken from the engine's compressor and ejected it through adjustable vents located over the flaps and ailerons. The air flow progressively increased as flaps were lowered. The angle of the variable wing was also reduced to 5° in place of the 7° of previous Crusader models. (Some sources claim the wing's angle was increased from 5°to 7°, but it was indeed a reduction from 7° to 5°). Also, the surface of the horizontal tailplane was increased to give better control at low speeds. This set of modifications had already been suggested to the US Navy by LTV but the Navy was satisfied enough with the Crusader's behaviour during approach and had not modified its F-8 fleet. The modifications allowed a decrease of 15 knots in the Crusader's landing speed and made it far less touchy during landing. A few years later, most US Crusaders received a mid-life update including the modifications designed for the F-8E(FN).
Other modifications concerned the weaponry. The F-8E(FN) kept the standard four gun and AIM-9 missile armament but was modified to be compatible with the French Matra R.530. The R.530 had a greater exhaust plume and a titanium deflector was added to protect the aircraft's flank while firing missiles. The Matra missile existed both in IR- and radar-guided versions, so a Magnavox AN/APQ-104 radar was installed as well as a modified AN/AWG-4 fire control system. The F-8E(FN) did not carry an IRST, unlike most American Crusaders. A 65 million US$ contract (AM-114-104) was signed, for the delivery of 40 single-seater and 6 twin-seater Crusaders, as well as a large stock of spares and engine. However, when Congress canceled the development of the “Twosader” trainer, the order was modified to 42 single-seaters. For administrative reasons, the US Navy gave the aircraft Bureau Numbers 115 to 151773. F-8D # 147036 was then modified by LTV to become the F-8E(FN) prototype. In addition to the modifications already described, it was equipped with a stall warning system, an autothrottle to maintain speed during approach, a J-57P-20A engine and measuring equipment. It first flew on 27 February 1964 under the designation YF-8E(FN). On April 11, during the 21st flight flown by Bob Rostine, the prototype crashed and was completely destroyed. Testing started again on June 26 when the first serial-production aircraft was fitted with a special probe and measuring equipment to carry on with the testing program. Simultaneously, weapons trial for the R.530 started in April on F-8E's based at China Lake NAS. Crusaders #2, 3 and 4 were also used for weapons trials. As early as November 1964, carrier launches and landings were carried out on USS Shangri-La, whose dimensions were roughly similar to those of the French carriers. These tests were carried out by James H. Flatley, Yves Goupil and Dick Gralow on French Crusaders #2 and 3. Following this successful trials campaign, the French Crusader was deemed ready to enter operational service in late 1964. During its career, the F-8E(FN) was modernized on several occasions. Its weaponry was progressively improved. Its four Sidewinder armament was rarely used and abandoned in 1986. The Crusaders were often equipped with the Matra R.530, whose reliability was quite bad. In 1980, a 65% failure rate was recorded, but the missile was kept in inventory until the late 1980's. A mix of one radar-guided and one IR-guided R.530 was often carried by the Crusader. The R.530 was replaced by the Matra R.550 Magic I, which was fitied to the Crusader in 1973. It was far more capable and reliable than the R.530 or early Sidewinders. The Super 530 was never used, as the AN.APQ-104 radar could not be made compatible with that missile. In 1988, the modernized Magic II was also introduced. Among other systems used on the Crusader, one might note a winch fitted on the port side if the fuselage to pull a target for gunnery training. This system was abandoned in 1988. In 1979, the J-57P-20A engines were equipped with a new afterburning system.
1.3 The renovated Crusader – F-8P In the late 1980's, the Marine Nationale faced an ever-increasing problem: its Crusader fleet was growing quite old and its replacement, the Rafale, could not be expected before the second half of the 1990's at best. Two options were considered. The first consisted in renting or purchasing F/A-18 Hornets from the US Navy as an interim measure while waiting for the Rafale. The other solution was to modernize the Crusader. Vice-Amiral Goupil, one of the first Crusader pilots,was one of the proponents of the Hornet solution and expressed his opinion and concern in the French Navy magazine “Cols Bleus” on 21 October 1989: The F/A-18 had already been evaluated by the Armée de l'Air and the Aéronavale in 1970 but no order had been placed. If the Hornet was inferior to the Crusader, as far as pure speed was concerned, it was nonetheless far more versatile and modern. Dassault was nevertheless worried that this might endanger its Rafale program and strongly opposed the idea. According to Goupil, only the Hornet purchase/rental option could give the Aéronavale the capacity to protect its carriers. Goupil insisted on the fact that maintaining the Crusader operational until 1996, the supposed (and optimistic) date of arrival of the Rafale, would be very expensive and of a limited interest. Some talk was made about fitting Mirage F.1 avionics and equipment on the Crusader but, as Goupil pointed out, “fitting the 1950's Crusader a technology dating back to 1975 could hardly be called modernization”. The debate went on for a while but this time the French aeronautical industry won and it was decided to renovate the F-8E(FN) Crusader while waiting for the Rafale. The winning argument was that if the Aéronavale were to equip with F/A-18s, the Armée de l'Air would be compelled to pay for the Rafale development on its own, which would have jeopardized the entire program. In the country's best interest, it was decided to simply overhaul the F-8's. Seventeen aircraft were to be modified by the aviation works in Cuers between 1990 and 1997: one aircraft every 18 month. Crusader #35 was the first to be modified and, in April 1993, underwent operational trials on the Clémenceau. The renovated F-8E(FN) was designated F-8P for prolongé (extended life). It was more of an overhaul than a modernization, although some modern equipment was fitted. The entire electrical and hydraulic system was replaced, and the structure was inspected for fatigue and reinforced. A Martin-Baker Mk 7 zero-zero ejection seat replaced the older zero-120 model. The radar and flight control systems were reconditioned. Only the avionics were really modernized. A VOR/ILS system was fitted, as well as an IFF, a GPS, a TACAN, a radar altimeter and a Thompson-CSF Sherloc radar warning receiver. The RWR was fitted in a rectangular fitting on the aircraft's fin, which distinguishes the F-8P from its predecessor. The cockpit layout was also changed and a new inertial navigation system, similar to that of the Mirage F.1, was installed. Despite the overhaul, the “Crouze” (as it was called by the French) was obsolete: it was not adapted to modern warfare environments and maintenance was increasingly difficult and heavy. The Crusader production lines had been stopped a long time ago and the French Navy depended on the Davis-Monthan AFB boneyard in Arizona for spares, when it didn't have to manufacture them itself.
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