F-100 to F-108 Supersonic Fighters
In 1962, TAC began replacing its F-100s with F-4s, but ten wings remained in 1964 when war in Indochina called them into action. None of these actions involved fighting enemy aircraft, since all were attacks on surface targets. Individual F-100D squadrons of four TAC Wings, beginning in August 1964 with the 3rd TFW, rotated through the area on tours of about six months, flying more sorties than all those by P-51s in World War II.
A new dimension to the air war was added by the hostile SA-2 Guideline surface-to-air missile (SAM). After these Soviet-built SAMs became effective in Viet Nam in July 1965, electronic counter measures were needed. Seven F-100F two-seaters, modified to the “Wild Weasel I” ECM version, began operations to detect and attack enemy radar sites on December 3, 1965.
The last F-100Ds in Vietnam, belonging to the 35th TFW, left in July 1971. The last “Hun” left Air Force service when the 27th TFW retired its F-100Ds in June 1972, but of 28 ANG F-100 squadrons, ten still continued to use F-100Ds in 1978. On November 10, 1979, the last operational flight by an ANG F-100D ended the first supersonic fighter’s USAF service.
The F-101 series McDonnell’s F-101A Voodoo was a long-range fighter based on the earlier XF-88. Powered by two J57-P-13 turbojets with afterburners, the Voodoo had a one-piece horizontal stabilizer set high on its fin, and mid-span ailerons on the thin 35-degree swept wing. Armament included four 20-mm M-39 guns with 200 rpg in the nose, with attachments below the fuselage for a nuclear bomb released by a LABS and 450-gallon drop tanks. Air refueling provisions were also provided.
Developed in response to a SAC requirement dated February 6, 1951, for a fighter to escort its bombers, the McDonnell Model 36W proposed in May was designated F-101 on November 20. A letter contract for 29 F-l0lAs was placed January 3,1952, the mockup inspected in July, and the first flown September 29, 1954, by Robert Little. Orders were increased to include 77 F-101A and 47 F-l0lC Voodoos.
The first 1,000-mph fighter in production, the F-l0lAs had been intended for SAC’s fighter escort units, but thorough testing of the first 40 aircraft revealed such serious problems that the Air Force suspended production from May 23 to November 26, 1956. F-101As did become operational with SAC’s 27th FBW in May 1957, but in July that unit was transferred to TAC, which wanted a low- altitude fighter-bomber that could deliver Mk 7 or Mk 28 nuclear bombs.
Essentially the F-101Cs, first flown August 21 and completed by May 1958, were identical except for wings strengthened for low-altitude tactical bombing. Delivery of the F-101C to the 27th FBW began in September, overlapping completion of the last As in October 1957.
On December 12, 1957, an F-101A modified with 16,900-pound thrust J57-P-55s, and no armament, set a 1,207-mph speed record. In 1958, the Voodoo fighters were transferred to the 81st TFW in Britain, serving until January 1966, when the last F-101C left, replaced by the F-4C.
For reconnaissance, two long-nose YRF-101As, first flown May 10, 1955, 35 RF-101As from June 1956, and 166 RF-101Cs were completed from July 1957 to March 1959 with six cameras and retaining their nuclear weapon capability. This application had a longer history, although it also entered TAC service in May 1957, replacing the RF-84Fs. During the Cuban Missile crisis of October 1962, 363rd TRW Voodoos flew low-level sorties over threatening missile sites.
Four RF-101Cs were transferred to the Chinese on Taiwan in November 1959 and another four were added later. After Air Force Voodoos were transferred to the ANG, 29 F-l0lAs were rebuilt as RF-l0lG and 32 F-101s as RF-101H aircraft.
Four RF-101Cs of the 15th TRS arrived at Tan Son Nhot on October 18, 1961, becoming the first Air Force unit to operate from Vietnam, and rotating RF-101 units continued to fly there until November 1970. Sorties over North Vietnam were the most dangerous, and the first RF-101 loss was on April 3, 1965. Seven more were lost to anti-aircraft fire in 1966.
The Voodoos had no trouble evading MiG-17s, but after a MiG-21 downed one in September 1967, RF-4Cs replaced the RF-101s on missions over North Vietnam, the older type confining itself to Laos and the south. By October 1971, all RF-101s had been transferred to the ANG.
Proposals for the aircraft itself were requested by the Air Force on June 18, 1950, and Convair, Lockheed and Republic were named the winners on July 2, 1951. On September 11, 1951, Convair got a design and mockup letter contract for an enlarged development of the delta wing XF-92A and two YF-102 prototypes were added December 19, 1951. The original design had a Wright J67 engine, Hughes MA-l fire control, and Falcon missiles.
When it was seen that the J67 and MA-l could not be completed in time, a J57-P-11 and MG-3 system was substituted for the interim YF-102 and F-102A, with the more sophisticated systems planned for the ultimate F-102B. Preliminary engineering on ten YF-102s began in April 1952 and the first 32 F-102A production aircraft were ordered December 17, 1952, on a contract approved the following June 12.
Carrying 1,194 pounds of armament, 1,050 gallons of fuel, and nearly a ton of electronics, the F-102 design was half again as heavy as the F-86D at combat weight, and the promised 870 mph at 35,000 feet could never be approached in actual flight. Even before the YF-102’s first flight on October 24, 1953, by Richard L. Johnson, wind tunnel tests warned that the drag hump at sonic speed was beyond the airplane’s capability. The first prototype encountered severe buffet at Mach 0.9 and crashed on its seventh takeoff. The second YF-102 flew January 11, 1954, but was limited to Mach .98 on the level, and dives over this speed resulted in severe yaw oscillations.