F-100 Super Sabre

The TAC request for a fighter-bomber was addressed with the F-100C which flew in March 1954 and entered service on 1955-07-14 with 450th Fighter Wing, Foster AFB. Operational testing in 1955 revealed that the F-100C was at best an interim solution, sharing all the vices of the F-100A. The uprated J57-P-21 engine boosted performance but continued to suffer from compressor stalls. On a positive note, the F-100C was considered an excellent platform for nuclear toss bombing because of its high top speed. The inertia coupling problem was more or less addressed with installation of a yaw damper in the 146th F-100C, later retrofitted to earlier aircraft. A pitch damper was added starting with the 301st F-100C, at a cost of US$10,000 per aircraft. The addition of "wet" hardpoints meant the F-100C could carry a pair of 275 US gal (1,040 L) and a pair of 200 US gal (770 L) drop tanks. However, the combination caused loss of directional stability at high speeds and the four tanks were soon replaced by a pair of 450 US gal (1,730 L) drop tanks. The 450s proved scarce and expensive and were often replaced by smaller 335 US gal (1,290 L) tanks. Most troubling to TAC was the fact that as of 1965, only 125 F-100Cs were capable of utilizing all non-nuclear weapons in the Air Force inventory, particularly cluster bombs and AIM-9 Sidewinder air-to-air missiles . By the time the F-100C was phased out in June 1970, 85 had been lost in major accidents. The U.S. Air Force Thunderbirds operated the F-100C from 1956 until 1964.

The definitive F-100D aimed to address the offensive shortcomings of the F-100C by being primarily a ground attack aircraft with secondary fighter capability. To this effect, the aircraft was fitted with autopilot, upgraded avionics, and, starting with the 184th production aircraft, the Sidewinder capability. In 1959, 65 aircraft were modified to also fire the AGM-12 Bullpup air-to-ground missile. To further address the dangerous flight characteristics, the wing span was extended by 26 inches (66 cm), and the vertical tail area was increased by 27%. The F-100D flew on 1956-01-24, entering service on 1956-09-29 with 405th Fighter Wing at Langley AFB. The aircraft suffered from reliability problems with the constant speed drive which provides constant-frequency current to electrical systems. In fact, the drive was so unreliable that USAF required it to have its own oil system to minimize damage in case of failure. Landing gear and brake parachute malfunctions claimed a number of aircraft, and the refueling probes had a tendency to break away during high speed maneuvers. Numerous post-production fixes created such a diversity of capabilities between individual aircraft that by 1965 around 700 F-100Ds underwent High Wire modifications to standardize the weapon systems. High Wire modifications took 60 days per aircraft at a total cost of US$150 million. In 1966, Combat Skyspot program fitted some F-100Ds with an X band radar transmitter to allow for ground-directed bombing in inclement weather or at night. In 1967, USAF began a structural reinforcement program to extend the aircraft's service life from the designed 3,000 flying hours to 7,000. Particular attention was paid to reinforcing the wings with external bracing strips after one aircraft suffered wing failure. Over 500 F-100Ds were lost, predominantly in accidents. During the Vietnam War, combat losses constituted as many as 50 aircraft per year. The aircraft was phased out of USAF active duty by 1972. On 1957-06-07, an F-100D fitted with an Astrodyne booster rocket making 150,000 lbf (667.2 kN) of thrust successfully performed a zero length launch. The capability was incorporated into late-production aircraft. After a major accident, the USAF Thunderbirds reverted from F-105 Thunderchief to the F-100D which they operated from 1964 until it was replaced by the F-4 Phantom II in 1968. In the early 1970s, Air National Guard units began fitting their F-100Ds with F-102 Delta Dagger-type afterburners which finally solved the compressor stall problems. The modifications cost US$8 million.

The F-100F two-seat trainer entered service in 1958. It received many of the same weapons and airframe upgrades as the F-100D, including the new afterburners. By 1970, 74 F-100Fs were lost in major accidents, and they mostly left USAF service by 1972.

Vietnam War

F-100D-50-NH

The F-100Ds arrived in Southeast Asia in 1962 but did not begin flying combat missions over Vietnam until 1965. The aircraft was used for ground attack within South Vietnam. The two-seat F-100F operated as a "fast-FAC" (forward air controller) spotting targets for other aircraft. It was also the first Wild Weasel SEAD aircraft whose specially trained crews were tasked with locating and destroying enemy air defenses. Four F-100F Wild Weasel I were fitted with an APR-25 vector radar homing and warning (RHAW) receiver, an IR-133 panoramic receiver with greater detection range, and a KA-60 panoramic camera. The RHAW could detect early warning radars and, most importantly, emissions from SA-2 Guideline tracking and guidance systems. These aircraft deployed to Korat Royal Thai Air Force Base in Thailand in November 1965, and began flying combat missions with 388th Tactical Fighter Wing in December. They were joined by three more aircraft in February 1966. All Wild Weasel F-100Fs were eventually modified to fire the AGM-45 Shrike anti-radiation missile.

The F-100 was progressively replaced in Vietnam by the F-4 Phantom II and the F-105 Thunderchief. In the Air National Guard units, the F-100 was replaced by the F-4, the A-7 Corsair II, and the A-10 Thunderbolt II, with the last aircraft retiring in 1979.

Notable achievements

• The first of the Century series fighters.
• The first operational aircraft in United States Air Force inventory capable of exceeding the speed of sound in level flight.
• On 1953-10-29, the first YF-100A prototype set a world speed record of 755.149 mph (656.207 knots, 1,215.295 km/h) at low altitude.
• On 1955-08-20, an F-100C set the first supersonic world speed record of 822.135 mph (714.416 knots, 1,232.098 km/h).
• On 1955-09-04, an F-100C won the Bendix Trophy, covering 2,235 miles (2,020 nm, 3,745 km) at an average speed of 610.726 mph (530.706 knots, 982.868 km/h).
• On 1956-12-26, two F-100Ds became the first-ever aircraft to successfully perform buddy refueling.
• On 1957-05-13, three F-100Cs set a new world distance record for single-engine aircraft by covering the 6,710 mile (5,835 nm, 10,805 km) distnace from London to Los Angeles in 14 hours and 4 minutes. The flight was accomplished using inflight refueling.
• On 1959-08-07, two F-100Fs became the first-ever jet fighters to fly over the North Pole.

Variants

After the Super Sabres were withdrawn from service a large number of them were converted into remote-controlled drones for use as targets for various antiaircraft weapons.

USAF Colonel and Medal of Honor recipent George E. "Bud" Day flew F-100s.

YF-100

Prototype, later designated TF-100A; two built.

F-100A

Single-seat day fighter; 203 built.

RF-100A

F-100A equipped for photoreconnaissance, six converted for Republic of China.

F-100B

See North American F-107

F-100BI

Proposed interceptor version of F-100B, did not advance beyond mockup.

F-100C

Additional fuel tanks in the wings, fighter-bomber capability, probe-and-drogue refueling capability, uprated J57-P-21 engine on late production aircraft. First flight March 1954; 476 built.

TF-100C

One F-100C converted into a two-seat training aircraft.

F-100D

Single-seat fighter-bomber, more advanced avionics, larger wing and tail fin, landing flaps. First flight 1956-01-24; 1,274 built.

F-100F

Two-seat training version, armament decreased from four to two cannon. First flight 1957-03-07, 339 built.

DF-100F

This designation was given to some F-100Fs that were used as drone directors.

NF-100F

Three F-100Fs used for test purposes, the prefix N indicates that modifications prevented return to regular operational service.

TF-100F

Temporary designation given to six F-100Fs exported to Denmark.

F-100J

Unbuilt all-weather export version for Japan.

F-100L

Unbuilt variant with a J57-P-55 engine.

F-100N

Unbuilt version with simplified avionics.

F-100S

Proposed French-built F-100F with Rolls-Royce Spey turbofan engine.

Operators

• Denmark (48), France (68), Taiwan (118), Turkey (87), United States Air Force.

Specifications (F-100D)

References