Republic F-105 Thunderchief

The History of the Republic F-105 Thunderchief

The F-105 Thunderchief was Republic Airlines' Cold War product, becoming the company's last production aircraft prior to its merger with Fairchild. The platform was developed as a follow-up to the F-84 family (also a Republic product) and continues the former's nuclear munitions capabilities.

With an impressive internal weapons bay and external hardpoints, the F-105 played a vital role in the Vietnam War, both as a strike fighter and as an anti-aircraft suppression ("Wild Weasel") platform.

Development

The origins of the Thunderchief series lie in a 1951 Republican private company plan to replace the existing Republican F-84F Thunderstreak/Thunderjet aircraft as a high-performance, supersonic tactical fighter-bomber. In fact, the design of the Thunderchief began long before the F-84 entered service with the U.S. Air Force.

Thunderchief The design was brought to the U.S. Air Force and quickly impressed with its multi-role capabilities and impressive performance potential. The YF-105A prototype completed and first flew on October 22, 1955, with its massive fuselage encasing the equally powerful 15,000-pound Pratt & Whitney J57-P-25 turbojet.

Only two of these prototypes were eventually built, but they soon became the largest single-seat, single-engine fighter jets in aviation history. Following these prototypes were four YF-105B models with updated 16,470-pound J75-P-3 engines with forward-facing engine inlets at the root of the wings.

Production models were received a few years later in the form of the F-105B model and based on the YF-105B prototype that arrived in USAF inventory on May 27, 1958. A total of 75 prototypes of the F-105B were produced, with a batch consisting of 10 pre-production aircraft and 65 production aircraft.

The USAF was interested in a photo-reconnaissance variant of the F-105B design, intended to be named RF-105B, but opted for the RF-101 Voodoo variant due to its proven status. Nonetheless, at least three RF-105s have been completed (those with flat camera noses and no photographic equipment), but these are only redesignated JF-105Bs. In its inception, Thunderchief was the heaviest and most technologically complex system the U.S.

Air Force has ever fielded. The Model B also served for some time with the U.S. Air Force's "Thunderbirds" performance group, but was later abandoned after the B-Series Riesling disintegrated in flight, and was replaced by a former Thunderbird mount - the F-100D Super saber.

The F-105C was originally planned to be a two-seat trainer, but it was cancelled before production began.

The F-105F became a two-seat, dual-role trainer/fighter-bomber and first flew in 1963. A total of 143 units were produced, the second-highest of all Thunderchief models. A second cockpit was added to the fuselage design, with the two pilots sitting side by side. The F model features a single Pratt & Whitney J75-P-19W engine with 24,500 pounds of static thrust with afterburner and 26,400 pounds of static thrust with water injection.

Artillery is limited to 14,000 pounds of conventional ammunition and special weapons. The default M61 20mm melee cannon is retained. Fifty-five of these models were later converted into the "wild weasel" role - responsible for destroying enemy surface-to-air missile positions - and received the serial number EF-105F model.

All F models were produced from 1963 to 1964.

Modifications and improvements to these EF-105F systems culminated in the F-105G Wild Weasels. The F-105G is powered by a Pratt & Whitney J75-P-19W with 26,500 pounds of thrust.

Performance specs include a top speed of 1,386 mph, a cruising speed of 596 mph, a range of 1,500 miles and a ceiling of 50,000 feet. Weapons suitably include anti-radiation air-to-surface missiles and specialized radar detection equipment.

Design

The overall lines of the F-105 Thunderchief are crisp and clear - from the pointy nose to the engine exhausts that extend beyond the vertical tail. The single-seat cockpit is located at the front of the fuselage and features an integrated design layout that complements the sleek silhouette of the aircraft's unique design. The center-wing monoplane was swept back and paired with smaller empennages on either side of the rear of the fuselage. The landing gear is a tricycle design, with two main landing gear recessed into each wing and the nose wheel recessed below the cockpit seating area. Engine air intakes are located on either side of the pilot's position and at the aft wing root, providing 23,500 pounds of thrust and afterburner for a single Pratt & Whitney J57-P-5 engine.

The air intakes also deserve special mention for their unique design - swept forward on the outside and recessed into the sides of the hull. From a top-down or bottom-up perspective, that contributes to the Thunder's already established look. On the ground, Thunderchiefs occupy a notoriously high position -- with a significantly elevated nose bridge -- and require a ladder that's nearly twice the height of the average pilot.

Armament will be secured to external hard points via optional internal bomb bay charges - in any case, the system is fully nuclear capable.

Armed

The standard armament of the Riesling is a 20mm M61 Vulcan, which fires 6,000 rounds per minute. This short-range weapon is complemented by a mixture of external and internal munitions, including conventional 750 and 1,000-pound drop bombs, incendiary bombs, air-to-air missiles, air-to-surface missiles, 2.75-inch rocket pods and other specialized (nuclear or other) required ) weapons, carried outside or inside the bomb bay under the fuselage. All told, Thunderchiefs can be armed with up to 8,000 pounds of ammunition against a variety of roles, often compared to an entire WWII bomber formation -- that's what the system has been capable of from the start. The 450-gallon fuel tank is also part of the weapon, as is the "buddy" tank.

Other systems include external chaff and torch dispensers.

Operational Services

The final F-105D model saw extensive service in the Vietnam War and was used by the U.S. Air Force after the Gulf of Tonkin incident.

Overall, within four years, the aircraft completed 75 percent of its missions to North Vietnamese targets and participated in an impressively large-scale air campaign known as Rolling Thunder. The aircraft has demonstrated its effectiveness, reliability and value against a wide range of targets in a variety of designated roles, and has demonstrated its impressive munitions transport and performance capabilities. Despite its nuclear capabilities, Rieslings are used only in conventional ordnance and are not limited to ground kills - several Rieslings have repeatedly killed enemy MiG fighters air-to-air during the conflict. The aircraft's operators include the 357th Tactical Fighter Squadron and the 388th Tactical Fighter Wing (the latter known as the Wild Weasel) of the 355th Tactical Fighter Wing out of Thailand.

Due to their heavy involvement in air combat (over 20,000 combat missions), Thunder Chiefs inevitably paid a heavy price - many (at least 350) were shot down over Vietnam, many by North Vietnamese anti-aircraft fire. Thunderchiefs were eliminated with the arrival of the classic McDonnell F-4 Phantom II.

Conclusion

Despite its sheer size, complexity, and high production costs, Thunder Chiefs became a top-notch performer in the Vietnam conflict. Its multifaceted design enables the system to assume a variety of essential battlefield roles and provides U.S. war planners with an essential component in air combat.

While the McDonnell F-4 Phantom II received (deserved) attention, Thunderchief continued to be a classic American series production warbird in its own right, proud of its achievements, and at least at the highest level, the system bridged The necessary gap between the early and late Vietnam War - and ultimately paved the way for an equally powerful aerial hot rod.

Specification

Basic

Production

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Dimensions

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Performance

Performance

Armor

Changes