Vought F 8 Crusader

Design and development

In September 1952, the United States Navy announced a requirement for a new fighter. It was to have a top speed of Mach 1.2 at 30,000 ft (9,144.0 m) with a climb rate of 25,000 ft/min (127.0 m/s), and a landing speed of no more than 100 mph (160 km/h). Korean War experience had demonstrated that 0.50 inch (12.7 mm) machine guns were no longer sufficient and as the result the new fighter was to carry a 20 mm (0.79 in) cannon. In response, the Vought team led by John Russell Clark, created the V-383. Unusual for a fighter, the aircraft had a high-mounted wing which necessitated the use of a fuselage-mounted short and light landing gear.

The Crusader was powered by a Pratt and Whitney J57 turbojet engine. The engine was equipped with an afterburner that, unlike on later engines, was either fully lit, or off (i.e. it did not have "zones"). The engine produced 18,000 lb of thrust at full power, enough to allow the F-8 to climb straight up in clean configuration. The Crusader was the first jet fighter in US service to reach 1,000 mph; U.S. Navy pilot R.W. Windsor reached 1,015 mph on a flight in 1956.

The most innovative aspect of the design was the variable-incidence wing which pivoted by 7° out of the fuselage on takeoff and landing (not to be confused with variable-sweep wing). This allowed a greater angle of attack, increasing lift without compromising forward visibility. This innovation helped the F-8's development team win the Collier Trophy in 1956. Simultaneously, the lift was augmented by leading-edge slats drooping by 25° and inboard flaps extending to 30°. The rest of the aircraft took advantage of contemporary aerodynamic innovations with area-ruled fuselage, all-moving stabilators, dog-tooth notching at the wing folds for improved yaw stability, and liberal use of titanium in the airframe. The armament, as specified by the Navy, consisted primarily of four 20 mm (.79 in) autocannon; the Crusader happened to be the last U.S. fighter designed with guns as its primary weapon. They were supplemented with a retractable tray with 32 unguided Mk 4/Mk 40 Folding-Fin Aerial Rocket (Mighty Mouse FFARs), and cheek pylons for two guided AIM-9 Sidewinder air-to-air missiles. Vought also presented a tactical reconnaissance version of the aircraft called the V-392.

Major competition came from the Grumman F-11 Tiger, the upgraded twin-engine McDonnell F3H Demon (which would eventually become the McDonnell Douglas F-4 Phantom II), and lastly, the North American F-100 Super Sabre hastily adapted to carrier use and dubbed the "Super Fury".

In May 1953, the Vought design was declared a winner and in June, Vought received an order for three XF8U-1 prototypes (after adoption of the unified designation system in September 1962, the F8U became the F-8). The first prototype flew on 25 March 1955 with John Konrad at the controls. The aircraft exceeded the speed of sound during its maiden flight. The development was so trouble-free that the second prototype, along with the first production F8U-1, flew on the same day, 30 September 1955. On 4 April 1956, the F8U-1 performed its first catapult launch from Forrestal.

Crusader III

In parallel with the F8U-1s and -2s, the Crusader design team was also working on a larger aircraft with ever greater performance, internally designated as the V-401. Although the Vought XF8U-3 Crusader III was externally similar to the Crusader and sharing with it such design elements as the variable incidence wing, the new fighter was larger and shared few components.

Operational history

Prototype XF8U-1s were evaluated by VX-3 beginning in late 1956, with few problems noted. Weapons development was conducted at Naval Air Weapons Station China Lake and a China Lake F8U-1 set a U.S. National speed record in August 1956. Commander "Duke" Windsor set, broke, and set a new Level Flight Speed Record of 1,015.428 mph (1,634.173 km/h) on 21 August 1956 beating the previous record of 822 mph (1,323 km/h) set by a USAF F-100. (It did not break the world speed record of 1,132 mph (1,822 km/h), set by the British Fairey Delta 2, on 10 March 1956.)

An early F8U-1 was modified as a photo-reconnaissance aircraft, becoming the first F8U-1P. Subsequently, the RF-8A was equipped with cameras rather than guns and missiles. On 16 July 1957, Major John H. Glenn, JR, USMC, completed the first supersonic transcontinental flight in a F8U-1P, flying from NAS Los Alamitos, California, to Floyd Bennett Field, New York, in 3 hours, 23 minutes, and 8.3 seconds.

First fleet operators

VX-3 was one of the first units to receive the F8U-1 in December 1956, and was the first to operate the type in April 1957, from the USS Franklin D. Roosevelt. VX-3 was the first unit to qualify for carrier operations but several aircraft were lost in accidents, several of them fatal to their pilots.

The first fleet squadron to fly the Crusader was VF-32 at NAS Cecil Field, Florida, in 1957, which deployed to the Mediterranean late that year on Saratoga. VF-32 renamed the squadron the "Swordsmen" in keeping with the Crusader theme. The Pacific Fleet received the first Crusaders at NAS Moffett Field in northern California and the VF-154 "Grandslammers" (named in honor of the new 1,000-mph jets and subsequently renamed the "Black Knights") began their F-8 operations. Later in 1957, in San Diego VMF-122 accepted the first Marine Corps Crusaders.

In 1962, the Defense Department standardized military aircraft designations generally along Air Force lines. Consequently, the F8U became the F-8, with the original F8U-1 redesignated F-8A.

Fleet service

The Crusader became a "day fighter" operating off the aircraft carriers. At the time, U.S. Navy carrier air wings had gone through a series of day and night fighter aircraft due to rapid advances in engines and avionics. Some squadrons operated aircraft for very short periods before being equipped with a newer higher performance aircraft. The Crusader was the first post-Korean War aircraft to have a relatively long tenure with the fleet and like the USAF Republic F-105 Thunderchief, a contemporary design, might have stayed in service longer if not for the Vietnam War and corresponding attrition from combat and operational losses.

Cuban Missile Crisis

The unarmed RF-8A proved good at getting low-altitude detailed photographs, leading to carrier deployments as detachments from the Navy's VFP-62 and VFP-63 squadrons and the Marines' VMCJ-2. Beginning on 23 October 1962 during the Cuban Missile Crisis, RF-8As flew extremely hazardous low-level photo reconnaissance missions over Cuba, the F-8's first true operational flights. Two-ship flights of RF-8As left Key West twice each day, to fly over Cuba at low level, then return to Jacksonville, where the film was offloaded and developed, to be rushed north to the Pentagon.

These flights confirmed that the Soviet Union was setting up IRBMs in Cuba. The RF-8As also monitored the withdrawal of the Soviet missiles. After each overflight, the aircraft was given a stencil of a dead chicken. The overflights went on for about six weeks and returned a total of 160,000 images. The pilots who flew the missions received Distinguished Flying Crosses, while VFP-62 and VMCJ-2 received the prestigious U.S. Navy Unit Commendation.

Mishap rate

The Crusader was not an easy aircraft to fly, and was often unforgiving in carrier landings, where it suffered from poor recovery from high sink rates, and the poorly designed, castoring nose undercarriage made it hard to steer on the deck. Safe landings required the carriers to steam at full speed to lower the relative landing speed for Crusader pilots. The stacks of the oil-burning carriers on which the Crusader served belched thick black smoke, sometimes obscuring the flight deck, forcing the Crusader's pilot to rely on the landing signal officer's radioed instructions. It earned a reputation as an "ensign eliminator" during its early service introduction. The nozzle and air intake were so low when the aircraft was on the ground or the flight deck that the crews called the aircraft "the Gator". Not surprisingly, the Crusader's mishap rate was relatively high compared to its contemporaries, the Douglas A-4 Skyhawk and the F-4 Phantom II. However, the aircraft did possess some amazing capabilities, as proved when several Crusader pilots took off with the wings folded. One of these episodes took place on 23 August 1960; a Crusader with the wings folded took off from Napoli Capodichino in full afterburner, climbed to 5,000 ft (1,500 m) and then returned to land successfully. The pilot, absentminded but evidently a good "stick man," complained that the control forces were higher than normal. The Crusader was capable of flying in this state, though the pilot would be required to reduce aircraft weight by ejecting stores and fuel before landing. In all, 1,261 Crusaders were built. By the time it was withdrawn from the fleet, 1,106 had been involved in mishaps. Only a handful of them were lost to enemy fire in Vietnam.

Vietnam War

When conflict erupted in the skies over North Vietnam, it was U.S. Navy Crusaders from the USS Hancock that first tangled with Vietnam People's Air Force (the North Vietnamese Air Force) MiG-17s, on 3 April 1965. The MiGs claimed the downing of a Crusader, and Lt Pham Ngoc Lan's gun camera revealed that his cannons had set an F-8 ablaze, but Lieutenant Commander Spence Thomas had managed to land his damaged Crusader at Da Nang Air Base, the remaining F-8s returning safely to their carrier. At the time, the Crusader was the best dogfighter the United States had against the nimble North Vietnamese MiGs. The U.S. Navy had evolved its "night fighter" role in the air wing to an all-weather interceptor, the F-4 Phantom II, equipped to engage incoming bombers at long range with missiles such as AIM-7 Sparrow as their sole air-to-air weapons, and maneuverability was not emphasized in their design. Some experts believed that the era of the dogfight was over as air-to-air missiles would knock down adversaries well before they could get close enough to engage in dogfighting. As aerial combat ensued over North Vietnam from 1965 to 1968, it became apparent that the dogfight was not over and the F-8 Crusader and a community trained to prevail in air-to-air combat was a key ingredient to success.

The Crusader also became a "bomb truck" in war, with both ship-based U.S. Navy units and land-based U.S. Marine Corps squadrons attacking communist forces in both North and South Vietnam.

USMC Crusaders flew only in the south, while U.S. Navy Crusaders flew only from the small Essex-class carriers. Marine Crusaders also operated in close air support missions.

Despite the "last gunfighter" moniker, the F-8s achieved only four victories with their cannon; the remainder were accomplished with AIM-9 Sidewinder missiles, partly due to the propensity of the 20 mm (.79 in) Colt Mk 12 cannons' feeding mechanism to jam under G-loading during high-speed dogfighting maneuvers. Between June and July 1966, during 12 engagements over North Vietnam, Crusaders claimed four MiG-17s for two losses. The Crusader would claim the best kill ratio of any American type in the Vietnam War, 19:3. Of the 19 aircraft claimed during aerial combat, 16 were MiG-17s and three were MiG-21s. U.S. records only indicate 3 F-8s lost in aerial combat, all to MiG-17 cannon fire in 1966, but the VPAF claimed 11 F-8s were shot down by MiGs. A total of 170 F-8 Crusaders would be lost to all causes - mostly ground fire and accidents -during the war.

Twilight service with U.S. Navy

LTV built and delivered the 1,219th (and last) U.S. Navy Crusader to VF-124 at NAS Miramar on 3 September 1964.

The last active duty Navy Crusader fighter variants were retired from VF-191 and VF-194 aboard Oriskany in 1976 after almost two decades of service, setting a first for a Navy fighter.

The photo reconnaissance variant continued to serve in the active duty Navy for yet another 11 years, with VFP-63 flying RF-8Gs up to 1982, and with the Naval Reserve flying their RF-8Gs in two squadrons (VFP-206 and VFP-306) at Naval Air Facility Washington / Andrews AFB until the disestablishment of VFP-306 in 1984 and VFP-206 on 29 March 1987 when the last operational Crusader was turned over to the National Air and Space Museum.

The F-8 Crusader is the only aircraft to have used the AIM-9C which is a radar-guided variant of the Sidewinder. When the Crusader retired, these missiles were converted to the AGM-122 Sidearm anti-radiation missiles used by United States attack helicopters to knock out enemy radars.

NASA

Several modified F-8s were used by NASA in the early 1970s, proving the viability of both digital fly-by-wire and supercritical wings.

French Navy

When the French Navy's air arm, the Aéronavale, required a carrier based fighter in the early 1960s to serve aboard the new carriers Clemenceau and Foch, the F-4 Phantom, then entering service with the United States Navy, proved to be too large for the small French ships. Following carrier trials aboard Clemenceau on 16 March 1962, by two VF-32 F-8s from the American carrier Saratoga, the Crusader was chosen and 42 F-8s were ordered, the last Crusaders produced.

The French Crusaders were based on the F-8E, but were modified in order to allow operations from the small French carriers, with the maximum angle of incidence of the aircraft's wing increased from five to seven degrees and blown flaps fitted. The aircraft's weapon system was modified to carry two French Matra R.530 radar or infra-red missiles as an alternative to Sidewinders, although the ability to carry the American missile was retained. Deliveries of the new aircraft, dubbed the F-8E(FN), started in October 1964 and continued until February 1965, with the Aéronavale's first squadron, Flotille 12F reactivated on 1 October 1964. To replace the old Corsairs, Flotille 14.F received its Crusaders on 1 March 1965.

In October 1974, (on Clemenceau) and June 1977 (on Foch), Crusaders from 14.F squadron participated in the Saphir missions over Djibouti. On 7 May 1977, two Crusaders went separately on patrol against supposedly French Air Force (4/11 Jura squadron) F-100 Super Sabres stationed at Djibouti. The leader intercepted two fighters and engaged a dogfight (supposed to be a training exercise) but quickly called his wingman for help as he had actually engaged two Yemeni Mikoyan-Gurevich MiG-21s. The two French fighters switched their master armament to "on" but, ultimately, everyone returned to their bases. This was the only combat interception by French Crusaders.

The Aéronavale Crusaders flew combat missions over Lebanon in 1983 escorting Dassault-Breguet Super Étendard strike aircraft. In October 1984, France sent Foch for Operation Mirmillon off the coast of Libya, intended to calm Colonel Ghaddafi down, with 12.F squadron. The escalation of the situation in the Persian Gulf, due to the Iran-Iraq conflict, triggered the deployment of Clemenceau task force and its air wing, including 12.F squadron. 1993 saw the beginning of the missions over ex-Yugoslavia. Crusaders were launched from both carriers cruising in the Adriatic Sea. These missions ceased in June 1999 with Operation Trident over Kosovo.

The French Crusaders were subject to a series of modifications throughout their life, being fitted with new F-8J-type wings in 1969 and having modified afterburners fitted in 1979. Armament was enhanced by the addition of R550 Magic infra-red guided missiles in 1973, with the improved, all-aspect Magic 2 fitted from 1988. The obsolete R.530 was withdrawn from use in 1989, leaving the Crusaders without a radar-guided missile. In 1989, when it was realised that the Crusader would not be replaced for several years, it was decided to refurbish the Crusaders to extend their operating life. Each aircraft was rewired and had its hydraulic system refurbished, while the airframe was strengthened to extend fatigue life. Avionics were improved, with a modified navigation suite and a new radar-warning receiver. The 17 refurbished aircraft were redesignated as F-8P (P used for "Prolongé" -extended- and not to be confused with the Philippine F-8P). Although the French Navy participated in combat operations in 1991 during Operation Desert Storm and over Kosovo in 1999, the Crusaders stayed behind and were eventually replaced by the Rafale M in 2000 as the last of the breed in military service.

Philippine Air Force

In late 1977, the Philippine government purchased 35 secondhand U.S. Navy F-8Hs that were stored at Davis-Monthan AFB in Arizona. Twenty-five of them were refurbished by Vought and the remaining 10 were used for spare parts. As part of the deal, the U.S. would train Philippine pilots in using the TF-8A. They were mostly used for intercepting Soviet bombers. The F-8s were grounded in 1988 and were finally withdrawn from service in 1991 after they were badly damaged by the Mount Pinatubo eruption, and have since been offered for sale as scrap.

Variants

Operators

France

Philippines

United States

Specifications (F-8E)

Data from The Great Book of Fighters and Quest for Performance Combat Aircraft since 1945 Joseph F. Baugher

General characteristics

Performance

Armament

Avionics
Magnavox AN/APQ-84 or AN/APQ-94 Fire-control radar