Republic Aviation in the U.S. began developing a supersonic tactical fighter-bomber in 1951, which took its first flight four years later on October 22. This was the start of a remarkable “Thud” that was going to echo timelessly in aviation history. The Republic F-105 Thunderchief was an American bomber aircraft created to replace the F-84F and was later nicknamed “Thud” for its renowned sound in the skies. The F-105 served the United States Air Force from 1958 to 1984 with its extraordinary Mach 2 bombing missions. It also became the only aircraft removed from combat due to high loss rates, especially during the Vietnam War. Upon entering service in 1958, the F-105 was the largest single-seat, single-engine combat aircraft, weighing around 50,000 lbs. The aircraft indeed made a heavy case against its competitors at the time.

Lightening before the Thunder

The development of the project lasted one year since 1951. The Republic Aviation team was led by Alexander Kartveli, who reviewed 108 design configurations before selecting the final outcome. There was special emphasis on the supersonic and low-altitude penetration aspects of the aircraft. Such emphasis was of major importance for delivering nuclear bombs. Additionally, the design featured a large engine, small wings with high wind loading, and a focus on low-altitude stability. Among all these features, including range, speed, and payload capacity, the maneuverability of the flight was a secondary focus. A year into the manufacturing, in 1952, Republic submitted a proposal to the U.S. Air Force, which supported the development of the project and suggested further modifications. By May 1952, the USAF had approved the project, and a contract for 199 aircraft had been issued. However, in March 1953, the USAF reduced the order to 37 fighter-bombers and 9 reconnaissance aircraft as the Korean War came to an end, and there was no more requirement for a higher amount. The program almost came to an end by late 1953 due to various delays and uncertainties but was restarted on June 28, 1954, with another official order of 15 F-105s.

First Thunder Strikes

After going through a suspension and then a restart, the prototype YF-105A finally took to the skies on October 22, 1955, from Republic Aviation’s test facility in Farmingdale, New York. The test pilot, John A. “Jack” D.T.W. “Pat” Patton achieved a top speed of Mach 1.2 during this flight; however, certain setbacks were observed. The aircraft felt underpowered and, faced issues with transonic drag, and went under further refinements in the design. The final F-105 design was a supersonic fighter bomber with the ability to carry nuclear weapons and heavy bomb loads at high speed. It was also an all-weather fighter bomber, fitted with mono-pulse and Doppler radar for night or bad weather operations. The internal weapons bay, initially designed for nuclear bombs, was modified to carry additional fuel tanks, while bombs were mounted externally on fuselage racks and wing pylons. The fuselage contained 1,184 gallons of fuel and an internal bomb bay, initially designed for nuclear weapons but often equipped with a 350-gallon fuel tank.

Moreover, the F-105D was also equipped with a retractable in-flight refueling probe to extend its range. The aircraft featured a mid-wing monoplane design with a 45-degree swept wing and tail surfaces. As the F-105 was optimized for low-level interdiction, its speed was a significant asset against enemy fighters such as the MiG-17 and MiG-21. Despite being less maneuverable than the smaller MiG fighters, the F-105 achieved 27.5 air-to-air victories. Later, the F-105D variant was upgraded with improved ejection seats, armor, gun sights, and electronic countermeasures.

“Thud” in the Skies

The F-105 was capable of carrying a bomb load of up to 14,000 lbs, greater than some World War II heavy bombers like the B-17 flying fortress. The first F-105D combat mission occurred on August 14 1964, targeting an anti-aircraft artillery site on the Plaine des Jarres. This mission was executed by aircraft from the 36th Tactical Fighter Squadron (TFS), part of the 6441st Tactical Fighter Wing, which was deployed from Yokota Air Base, Japan, to Korat Royal Thai Air Force Base, Thailand. The first Thunderchief was lost during this mission, although the pilot successfully returned the aircraft to Korat. The aircraft played a major role during the Vietnam War, and over 20,000 Thunderchief sorties were flown throughout the war, but the aircraft suffered heavy losses. Of the 833 units produced, 382 were lost, including 62 in non-combat operations. Later in its service, the F-105 was developed into a two-seat Wild Weasel version for Suppression of Enemy Air Defenses (SEAD), particularly targeting surface-to-air missile (S.A.M.) sites. However, the Wild Weasel variants of the Thunderchief remained in service until early 1984, when they were replaced by the F-4G Wild Weasel V.

The Last Strike

Despite its shortcomings, the Thunderchief left a lasting legacy and contributed valuable test data that influenced future aircraft designs. The aircraft was replaced in the Vietnam War by other aircraft, primarily the F-4 Phantom II. The last F-105D unit, the 355th Tactical Fighter Wing, based at Takhli Royal Thai Air Force Base (RTAFB), Thailand, began returning to the U.S. in October 1970. The Thunderchief was rapidly withdrawn from the United States Air Force (USAF) service after the Vietnam War. Following the war, the USAF began transferring the remaining aircraft to Air Force Reserve (AFRES) and Air National Guard (A.N.G.) units. By the late 1970s, the ageing Thunderchiefs were becoming difficult to maintain, and the last F-105Gs, belonging to the 128th Tactical Fighter Squadron of the Georgia A.N.G., were retired on May 25 1983. The final flight of the F-105 Thunderchief occurred on February 25, 1984, by the AFRES 466th Tactical Fighter Squadron with F-105Ds. Preserved F-105 Thunderchief aircraft are located in various museums, living on an eternal legacy.

Today in Aviation History is a series highlighting the achievements, innovations, and milestones that have shaped the skies. All the previous anniversaries are available HERE

Haritima Maurya

"Haritima Maurya, pen name, ""Another Stardust,"" has been passionate about writing since her school days and later began sharing her work online in 2019. She was drawn to writing because of her love for reading, being starstruck by the art of expression and how someone can make you see and feel things exclusive to their experience. She wanted to be able to do that herself and share her mind with world cause she believes while we co exist in this beautiful world least we can do is share our little worlds within.

As a commercial pilot, Haritima balances her passion for aviation with her love for storytelling. She believes that, much like flying, writing offers a perspective beyond the ordinary, offering a bridge between individual experiences and collective understanding.

Through her work, ""Another Stardust"" aims to capture the nuances of life, giving voice to moments that resonate universally. "

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