View source for Republic F-105 Thunderchief

{{Short description|US Air Force supersonic fighter-bomber}}
{{Good article}}
{{Use dmy dates|date=October 2019}}
{{Use American English|date=September 2023}}
{{Infobox aircraft
 |name= F-105 Thunderchief
 |image= File:Republic F-105D-30-RE (SN 62-4234) in flight with full bomb load 060901-F-1234S-013.jpg
 |caption= An F-105D Thunderchief flying with a full load of sixteen {{convert|750|lb|kg|abbr=on}} bombs on its five hardpoints
 |alt= 
 |type= [[Fighter-bomber]]
 |national_origin= United States
 |manufacturer= [[Republic Aviation]]
 |designer= <!--Only appropriate for single designers, not project leaders. -->
 |first_flight= 22 October 1955
 |introduction= 27 May 1958
 |retired= 25 February 1984
 |primary_user= [[United States Air Force]]
 |more_users=
 |number_built= 833
 |produced= 1955&ndash;1964
 |status= 
 |variants=
}}

The '''Republic F-105 Thunderchief''' is an American [[fighter-bomber]] that served with the [[United States Air Force]] from 1958 to 1984. Capable of [[Supersonic speed|Mach]] 2, it conducted the majority of strike bombing missions during the early years of the [[Vietnam War]]. It was originally designed as a single-seat, nuclear-[[attack aircraft]]; a two-seat [[Wild Weasel]] version was later developed for the specialized [[suppression of enemy air defenses]] (SEAD) role against [[surface-to-air missile]] sites. The F-105 was commonly known as the "Thud" by its crews. It is the only American aircraft to have been removed from combat due to high loss rates.<ref>Davies 2010, p. 6.</ref>

As a follow-on to the Mach 1 capable [[North American F-100 Super Sabre]], the F-105 was also armed with missiles and a rotary cannon; however, its design was tailored to high-speed low-altitude penetration carrying a single [[nuclear weapon]] internally. First flown in 1955, the Thunderchief entered service in 1958. The single-engine F-105 could deliver a bomb load greater than some American [[heavy bomber]]s of [[World War II]] such as the [[Boeing B-17 Flying Fortress]] and [[Consolidated B-24 Liberator]]. The F-105 was one of the primary attack aircraft of the Vietnam War, with over 20,000 Thunderchief sorties flown. Out of the 833 produced, 382 aircraft were lost, including 62 operational (non-combat) losses. Although less agile than smaller MiG fighters, USAF F-105s were credited with 27.5 kills.

During the conflict, the single-seat F-105D was the primary aircraft delivering heavy bomb loads against the various military targets. Meanwhile, the two-seat F-105F and F-105G Wild Weasel variants became the first dedicated SEAD platforms, fighting against the [[Soviet Union|Soviet]]-built [[S-75 Dvina]] ([[NATO reporting name]]: SA-2 ''Guideline'') surface-to-air missiles. Two Wild Weasel pilots were awarded the [[Medal of Honor]] for attacking North Vietnamese surface-to-air missile sites, with one shooting down two [[Mikoyan-Gurevich MiG-17|MiG-17s]] the same day. The dangerous missions often required them to be the "first in, last out", suppressing enemy air defenses while strike aircraft accomplished their missions and then left the area.

When the Thunderchief entered service it was the largest single-seat, single-engine combat aircraft in history, weighing approximately {{convert|50000|lb|kg|sigfig=2}}.<ref name="Crosby">Crosby 2002, p. 229.</ref> It could exceed the [[speed of sound]] at sea level and reach Mach 2 at high altitude.<ref name="F-105D"/> The F-105 could carry up to {{convert|14000|lb|kg|abbr=on|sigfig=2}} of bombs and missiles. The Thunderchief was later replaced as a strike aircraft over North Vietnam by both the [[McDonnell Douglas F-4 Phantom II]] and the swing-wing [[General Dynamics F-111 Aardvark]]. However, the "Wild Weasel" variants of the F-105 remained in service until early 1984, at which point they were replaced by the specialized [[McDonnell Douglas F-4 Phantom II#Variants|F-4G "Wild Weasel V"]].

==Development==
===Design phase===
[[Republic Aviation]] started work on what would become the Thunderchief during 1951.<ref name=Knaack_p191>Knaack 1978, p. 191.</ref> It was conceived of as an internal project to produce a replacement for the [[Republic F-84F Thunderstreak|RF-84F Thunderflash]], which first used the characteristic wing-root air intakes to make room for cameras in the nose section. The design team led by [[Alexander Kartveli]] examined some 108 configurations before settling on a large, single-engine ''AP-63FBX'' (Advanced Project 63 Fighter Bomber, Experimental), specifically AP-63-31.<ref name=Knaack_p191/> The new aircraft was intended primarily for supersonic, low altitude penetration to deliver a single, internally carried nuclear bomb. The emphasis was placed on low-altitude speed and flight characteristics, range, and payload. The aircraft would be fitted with a large engine, and a relatively small wing with a high [[wing loading]] for a stable ride at low altitudes, and less drag at supersonic speeds.<ref name=Davies_p6-7>Davies 2010, pp. 6–7.</ref> Traditional fighter attributes such as maneuverability were a secondary consideration.<ref name=Green>Green and Swanborough 2001, pp. 500–501.</ref>

During April 1952, Republic made its contractor proposal, which contained many of the features that the [[United States Air Force]] (USAF) would have liked the RF-84F to have been outfitted with had it been technically possible; one month later, the Air Staff endorsed its development over that of further developing the RF-84F.<ref name=Knaack_p191/> The USAF promptly issued Republic with an initial contract covering preproduction engineering, tooling, as well as the production of 199 aircraft, the first of which was to be operationally ready by 1955.<ref>Anderton 1983, p. 18.</ref> However, by March 1953, the USAF had reduced the order to 37 fighter-bombers and nine tactical reconnaissance aircraft, citing the approaching end of the [[Korean War]]. In October 1953, the F-105 mock-up was inspected; no major changes were recommended.<ref name=Knaack_p191/> By this point, the aircraft had grown so large that the [[Allison J71]] [[turbojet]] intended for it was abandoned in favor of the more powerful [[Pratt & Whitney J75]]. Anticipating a protracted development of the engine, it was expected that the first aircraft would use the smaller [[Pratt & Whitney J57]]. Near the end of 1953, the entire program was suspended by the USAF due to a number of delays and uncertainties regarding the aircraft.<ref name=Knaack_p191/> However, on 28 June 1954, the USAF officially ordered 15 F-105s (two YF-105As, four YF-105Bs, six F-105Bs, and three RF-105Bs) under the Weapon System designation ''WS-306A''.<ref name=Knaack_p191-192>Knaack 1978, pp. 191-192.</ref><ref name="AIAp86 p186">Peacock 1986, p. 186.</ref><ref>Anderton 1983, pp. 18-19.</ref>

===Initial flights===
[[File:Republic YF-105A (SN 54-0098, the first of two prototypes) 060831-F-1234S-039.jpg|thumb|Republic YF-105A, AF Ser. No. 54-0098, the first of two prototypes]]

On 22 October 1955, the YF-105A prototype made its [[maiden flight]]. After 22 hours of flight time, the prototype was returned to the factory for repairs after sustaining major damage.<ref name=Knaack_p192/> The second YF-105A made its first flight on 28 January 1956.<ref name="AIAp86 p186"/> Despite being powered by a less potent J57-P-25 engine with {{convert|15000|lbf|kN|lk=on|sigfig=2}} of [[afterburner|afterburning]] thrust, the first prototype attained the speed of Mach 1.2 on its maiden flight. (The J75 was expected to generate {{convert|24500|lbf|kN|abbr=on|sigfig=3}} with afterburner.)<ref name="Angel p408,0">Angelucci and Bowers 1987, pp. 408, 410.</ref> Both aircraft featured conventional wing root air intakes and slab-sided fuselages typical of the early jets; Republic viewed the prototypes as not being representative of the true capability of the aircraft due to numerous changes that were enacted prior to production.<ref>Anderton 1983, p. 22.</ref> Specifically, insufficient power and aerodynamic problems with [[transonic]] [[drag (physics)|drag]], as well as [[Convair]]'s experience with their [[Convair F-102 Delta Dagger|F-102]], had led to a redesign of the fuselage to conform to the [[area rule]], giving it a characteristic "wasp waist".<ref>Anderton 1983, pp. 28-32.</ref> The F-105's reworked air intake was designed with a unique forward-swept shape, which was derived from [[Antonio Ferri]]'s work on the proposed [[Republic XF-103]] ramjet-powered interceptor.<ref>{{Cite book |last=Davies |first=Peter E. |url=https://books.google.com/books?id=JVKbCwAAQBAJ&pg=PA12 |title=Republic F-105 Thunderchief |collaboration=Illustrated by Adam Tooby, Henry Morshead |date=2012 |publisher=Bloomsbury Publishing |isbn=9781780961743 |quote=One of the F-105's most distinctive features, its swept-forward air intakes, was also added at this stage. Derived by Antonio Ferri from work on the XF-103 interceptor, the intakes performed far better than the original type at high speeds. They included moveable 'plugs' to change the cross-section of the intake and match the airflow to the engine's requirements at varying flight speeds. The plugs and associated internal bleed-air doors were controlled by the aircraft's Bendix central air data computer (CADC).}}</ref> In combination with the distinctive forward-swept variable-geometry air intakes, which regulated airflow to the engine at supersonic speeds, and the J75 engine, this redesign enabled the F-105B to attain Mach 2.15.<ref name="IAPR6 p124-5">Davis 2002, pp. 124–125.</ref><ref name="Angel p408">Angelucci and Bowers 1987, p. 408.</ref>

[[File:17th Wild Weasel Squadron F-105 Flightline.jpg|alt=This is a flightline of F-105s of the 17th.|thumb|The 17th Wild Weasel squadron with a F-105 flightline. The F-105 was also used for "Wild Weasel" anti-radar missions carrying AGMs.]]
During March 1956, the USAF placed a further order for 65 F-105Bs and 17 RF-105Bs.<ref name=Knaack_p192>Knaack 1978, p. 192.</ref> In order to conduct the nuclear mission, an MA-8 [[fire control system]], [[List of radars#AN/APG Series|AN/APG-31]] ranging [[radar]], and K-19 gunsight to allow for [[toss bombing]] were integrated.<ref>Anderton 1983, p. 25.</ref> On 26 May 1956, the first pre-production YF-105B made its maiden flight.<ref name=Knaack_p192/> Five of the F-105C trainer variant were added to the procurement plan in June 1956, before being canceled during 1957. The RF-105 reconnaissance variant was canceled in July 1956.<ref name=Richardson_p12-3/> The first production F-105B was accepted by the USAF on 27 May 1957.<ref name=Knaack_p193>Knaack 1978, p. 193.</ref> In June 1957, Republic Aviation requested that the F-105 be named ''Thunderchief'', continuing the sequence of the company's Thunder-named aircraft: [[Republic P-47 Thunderbolt|P-47 Thunderbolt]], [[Republic F-84 Thunderjet|F-84 Thunderjet]], and F-84F Thunderstreak. The USAF made this name official one month later.<ref name=Richardson_p12-3>Richardson 1992, pp. 12–13.</ref>

===Later development===
To fulfill the USAF's requirement for an all-weather attack aircraft, Republic proposed the F-105D variant during 1957.<ref name=Knaack_p193/> This version featured an enlarged nose and radome housing the AN/ASG-19 ''Thunderstick'' bombing/navigation system. The AN/ASG-19 was designed around the [[Autonetics]] R-14A radar, which operated in both air-to-air and air-to-ground modes, and the AN/APN-131 Doppler navigation radar. In the cockpit, the F-105D featured vertical-tape instrument displays for adverse weather operation. The ability to carry the [[B43 nuclear bomb|TX-43 nuclear weapon]] was also added. On account of these myriad changes, Republic noted the difficulty of using the same production line as had been used for the F-105B; production times would also be extended from 144 days to 214 days.<ref name=Knaack_p196>Knaack 1978, p. 196.</ref>

Development of the RF-105 reconnaissance model was restarted during the late 1950s, for a time based on the F-105D, before work on the model was cancelled for the final time on 23 December 1960.<ref name=Knaack_p199/> On 18 March 1959, the planned F-105E twin-seater was also cancelled due to its high cost; it was replaced on a one-to-one basis by additional F-105Ds.<ref name=Knaack_p196/> On 9 June 1959, the first F-105D took its maiden flight.<ref name=Richardson_p12-5>Richardson 1992, pp. 12–13, 15.</ref> Flight testing of the F-105D was somewhat less troubled than the less advanced F-105B, to the point where the D-model was ready for operational service ahead of its predecessor.<ref name=Knaack_p196-197>Knaack 1978, pp. 196-197.</ref> Category II flight testing in late 1959 identified various key deficiencies on the F-105B, particularly with the MA-8 fire control system and autopilot of this variant.<ref name=Knaack_p194/> While eventually rectified successfully, it took time to develop and deploy appropriate modifications, putting the production programme further behind. By the start of 1960, none of the 56 F-105Bs that had been delivered were considered to be operationally ready.<ref name=Knaack_p194/>

[[File:F-105 Thunderchiefs Mt Fuji.jpg|thumb|A USAF F-105F trainer and a F-105D with [[Mount Fuji]] in the background]]
At one point, there were plans in progress to procure in excess of 1,500 F-105Ds; however, production schedules continued to be missed, in part due to [[industrial action|strikes]] by Republic's workforce, that impacted the USAF's plans for the type.<ref name=Knaack_p198>Knaack 1978, p. 198.</ref> Production of the F-105 was heavily impacted by the decision taken by Secretary of Defense [[Robert McNamara]] to equip no more than seven combat wings with the type. During November 1961, production of the type was cut in favor of the USAF adopting the Navy's F-4 Phantom II,<ref name="IAPR6 p130">Davis 2002, p. 130.</ref> and in the longer term, the [[General Dynamics F-111 Aardvark]] of the TFX program.<ref>Anderton 1983, pp. 62-63.</ref> While considerations towards reopening production of the F-105 were discussed in 1967, this interest did not ultimately see any such revival.<ref name=Knaack_p200>Knaack 1978, p. 200.</ref>

The final 143 Thunderchiefs built were of the two-seat F-105F trainer variant.<ref name=Knaack_p201>Knaack 1978, p. 201.</ref> Based on the F-105D, this model was 31&nbsp;inches (79&nbsp;cm) longer to provide room for the rear cockpit; otherwise, the aircraft had similar flight performance to the preceding F-105D.<ref name=Richardson_p20>Richardson 1992, p. 20.</ref><ref>Anderton 1983, p. 75.</ref> A total of 833 F-105s were completed before production ended in 1964.<ref name="Angel p410">Angelucci 1987, p. 410.</ref> The F-105 had been designed for a short nuclear campaign, leading to shortcomings that became evident in a lengthy conventional war, such as a poor [[hydraulic]]s layout and fuel tanks that were not [[Self-sealing fuel tank|self-sealing]].<ref>{{cite magazine |last=Werrell |first=Kenneth |title=Did USAF Technology Fail in Vietnam? |url=http://www.airpower.maxwell.af.mil/airchronicles/apj/apj98/spr98/werrell.pdf |url-status=dead |archive-url=https://web.archive.org/web/20161230073700/http://www.airpower.maxwell.af.mil/airchronicles/apj/apj98/spr98/werrell.pdf |archive-date=30 December 2016 |magazine=Airpower Journal |date=Spring 1998 |pages=87–99}}</ref> Subsequent upgrades improved the reliability and weapons capacity of the existing F-105Ds. In response to the surface-to-air missile threat experienced in the skies above Vietnam, dozens of F-105Fs were converted into anti-radar "Wild Weasel" aircraft, culminating with the F-105G.<ref name=Richardson_p28_38>Richardson 1992, pp. 28, 32–33, 38.</ref><ref>Anderton 1983, pp. 125-126.</ref><ref name=Knaack_p203>Knaack 1978, p. 203.</ref>

==Design==
===Overview===
[[File:Republic F-105B with avionics layout 060831-F-1234S-046.jpg|thumb|upright|Front view of Republic F-105B with avionics layout]]

The F-105 was a mid-wing monoplane with a 45° [[swept wing]] and tail surfaces. The single engine was fed by two intakes in the wing roots, leaving the nose free for a [[radome]] housing the multi-mode radar.<ref name="JAWA66 p243-4">Taylor 1966, pp. 243–244.</ref> Its fuselage provided room for {{convert|1184|gal|L|lk=on|sigfig=3}} of fuel and an internal bomb bay.  The bomb bay measured {{convert|15|ft|10|in|m|sigfig=3}} by {{convert|32|in|m|abbr=on|sigfig=2}} by {{convert|32|in|m|abbr=on|sigfig=2}}; it was originally designed to carry a single [[nuclear weapon]] but typically held an additional {{convert|350|gal|L|abbr=on|sigfig=2}} fuel tank.<ref>''Republic F-105 Thunderchief Pilot's Flight Operating Instructions'' 2008, p. 16.</ref> It featured four under-wing and one centerline pylon; the two inner wing and centerline pylons were capable of accepting fuel from {{convert|450|and|650|gal|L|abbr=on|sigfig=2}} [[drop tank]]s. Two outer dry stations were wired for missiles or bombs.<ref name="Tech p47">Davis and Menard 1998, p. 47.</ref><ref name="IAPR6 p141">Davis 2002, p. 141.</ref> One [[M61 Vulcan]] (initially designated ''T-171E3'') [[20 mm caliber|20 mm]] 6-barrel [[Rotary cannon|Gatling-style cannon]] was installed in the left side of the nose. A short-range [[AIM-9 Sidewinder]] air-to-air missile could be carried on each of the outer wing pylons.<ref name=Richardson_p22-4>Richardson 1992, pp. 22–24.</ref>

The F-105 was designed primarily for low-level interdiction and its low-altitude speed was its greatest asset when dealing with enemy fighters such as the [[Mikoyan-Gurevich MiG-17|MiG-17]]/[[Shenyang J-5|J-5]]s<ref>Toperczer 2001, pp. 65–74.</ref> and [[Mikoyan-Gurevich MiG-21|MiG-21]]. The F-105 managed 27.5 air-to-air victories.<ref name="Futrell p157">Futrell et al. 1976, p. 157.</ref> Based on combat experience, the F-105D was updated with a better [[ejection seat]], additional armor, improved gun sights, and [[Electronic countermeasure|Electronic Counter Measures]] (ECM) pods on the wings.<ref name=Knaack_p199>Knaack 1978, p. 199.</ref>

===Flight characteristics===
[[File:F-105 Thunderchiefs refuel.jpg|thumb|left|F-105D Thunderchiefs refueling from a [[Boeing KC-135]] tanker]]

Former [[North American F-86 Sabre]] pilot Jerry Noel Hoblit recalled being in awe of the F-105's size after seeing it for the first time; he could not manage to reach the air intake lip even with a running jump. The F-105 had a spacious cockpit with good visibility and layout (particularly after the introduction of "tape" instruments); the advanced electronics were easy to learn and operate. Takeoffs and landings were often performed in the {{convert|230|mph|km/h|abbr=on|sigfig=2}} range. The [[spoiler (aeronautics)|spoilers]] provided good roll control at all speeds and the distinctive four-petal [[Air brake (aircraft)|airbrakes]] (which also opened slightly when the afterburner was engaged to allow for the larger flow of exhaust gases) were highly effective even at supersonic speeds. Loss of control due to a [[spin (flight)|spin]] or complications of [[adverse yaw]] required deliberate effort from the pilot and spontaneous spin recovery was rapid.<ref name=Higham />

The initial reaction of the fighter pilot community to their new aircraft was lukewarm. Between its massive dimensions and troubled early service life, the F-105 had garnered a number of uncomplimentary nicknames. In addition to the aforementioned "Thud", nicknames included the "Squat Bomber", "Lead Sled", and the "Hyper Hog" and/or "Ultra Hog".<ref>Anderton 1983, p. 11.</ref> The latter two names arose from the F-105's predecessors, the Republic F-84 Thunderjet and F-84F Thunderstreak, nicknamed "Hog" and "Super Hog", respectively. According to F-105 pilots and crews, the "Thud" nickname was inspired by the character "Chief Thunderthud" from the ''[[Howdy Doody]]'' television series.<ref>{{cite web |last1=Laurence |first1=Mike |title=The Thud |url=http://faculty.buffalostate.edu/fishlm/folksongs/thud.htm |date=7 January 1994 |access-date=18 April 2015 |archive-date=3 March 2016 |archive-url=https://web.archive.org/web/20160303215417/http://faculty.buffalostate.edu/fishlm/folksongs/thud.htm |url-status=live }}</ref>

[[File:F105D M61.gif|thumb|20mm [[M61 Vulcan]] firing test aboard an F-105D Thunderchief.]]
The aircraft's offensive capabilities were sarcastically referred to as a "Triple Threat"—it could bomb you, strafe you, or fall on you.<ref>Hannah,&nbsp;C.&nbsp;C. (2002). ''Striving for Air Superiority: The Tactical Air Command in Vietnam''. United States:&nbsp;Texas A&M University Press. p. 49.</ref> Positive aspects, such as the F-105's responsive controls, strong performance at high speed and low altitude, and its outfit of electronics won over some pilots. For some, "Thud" was a term of endearment; retroactively the RF-84F Thunderflash became known as "Thud's Mother".<ref name=Higham>Higham and Williams 1975, pp. 185–190.</ref> F-105 pilot Colonel [[Jacksel M. Broughton|Jack Broughton]] said of the nickname: "The Thud has justified herself, and the name that was originally spoken with a sneer has become one of utmost respect through the air fraternity".<ref>Broughton 2006, pp. 38–39.</ref>

===Special modifications===
====Commando Nail====
[[File:Republic F-105 Thunderchief - cockpit.jpg|thumb|The [[cockpit]] of an F-105 Thunderchief]]

The rear cockpits of several two-seat F-105Fs were modified under project ''Commando Nail'' with an R-14A radar and a radar scope that offered high resolution. These aircraft were used for all-weather and night low-level strikes against especially dangerous targets by a unit from the [[13th Fighter Squadron|13th Tactical Fighter Squadron]] (1966–1975) dubbed "Ryan's Raiders" starting in April 1967.<ref name="AIAp86 p206">Peacock 1986, p. 206.</ref><ref name="WoF18 p26-7">Davis 2000, pp. 26–27.</ref> Some of these aircraft were later converted to the Wild Weasel III standard.<ref name=Knaack_p202>Knaack 1978, p. 202.</ref><ref name="WoF18 p27-8">Davis 2000, pp. 27–28.</ref>

In an effort to thwart MiG attacks, several F-105Fs were also fitted with [[Hallicrafters]] QRC-128 communication jamming system under project ''Combat Martin''. The North Vietnamese interceptor force followed Soviet air-defense doctrine, with pilots under rigid direction of ground controllers over radio links. The QRC-128, nicknamed "Colonel Computer", filled up the rear cockpit of the F-105F.<ref>Davis and Menard 1998, p. 49.</ref> It bounced voice communications over the radio channel back out after a delay, resulting in an obnoxious garble. However, the first time the Combat Martin was used, the US [[National Security Agency]] (NSA), in charge of US strategic [[signals intelligence]], ordered the Air Force to cease and desist immediately, since the NSA believed that the intelligence obtained by monitoring the channels outweighed the benefits of jamming them.<ref name=Price>Price 1989, {{Page needed|date=July 2011}}</ref>

====Thunderstick II====
Experience in Vietnam demonstrated the need for a better visual and blind bombing capability. In March 1968, the Air Force ordered development of an upgraded bombing/navigation system, incorporating a Singer-General Precision [[inertial navigation system]], improvements to the AN/APN-131 navigation radar, and solid-state circuitry for the R-14A radar, which was redesignated R-14K. Furthermore, the digital AN/ARN-92 [[LORAN|long-range navigation]] receiver replaced the problematic AN/ARN-85 receiver. The additional avionics were housed in a long, raised dorsal spine. The modified bombing/navigation system was known as ''Thunderstick II''. F-105s with this system could achieve a bombing [[Circular error probable|circular error of probability]] (CEP) of {{convert|50|ft|m|sigfig=2}} from an altitude of {{convert|15000|ft|m|abbr=on|sigfig=2}}. Although the first Thunderstick II aircraft flew in 1969, they were not used in Vietnam. A total of 30 F-105Ds received this modification.<ref name="IAPR6 p137">Davis 2002, p. 137.</ref> They were initially assigned to the 563TFS/23TFW at McConnell AFB. In the summer 1972, they were all transferred to the newly reactivated 457TFS (AFRES) at Carswell AFB.  This remained the only unit to fly the Thunderstick II until its retirement in 1981–82.{{citation needed|date=October 2024}}

===Wild Weasel===
In 1965, the USAF began operating two-seat [[North American F-100 Super Sabre|North American F-100F Super Sabre]]s specially equipped for [[Suppression of Enemy Air Defenses]] (SEAD) missions in Vietnam. Nicknamed the Wild Weasel, these aircraft achieved a number of victories against North Vietnamese surface-to-air missile radars. The second crew member was a [[Combat Systems Officer|Navigator]] trained as an Electronic Warfare Officer (EWO) to decipher sensor information and guide the pilot towards the targets.<ref name="Dorr de p60-1">Dorr and Bishop 1996, pp. 60–61.</ref> However, the F-100F was an interim solution, since its limited payload often required multiple aircraft to conduct a successful strike; it also lacked the speed and endurance to effectively protect the F-105.<ref name="Lake p31">Lake 2004, p. 31.</ref><ref name="IAPR6 p135">Davis 2002, p. 135.</ref>

[[File:Republic F-105F 060928-F-1234S-017.jpg|thumb|upright=1.15|left|F-105F with armament layout in August 1964; including 20&nbsp;mm (0.79&nbsp;in) cannon rounds, 2.75&nbsp;in (70&nbsp;mm) rockets, Bullpup and Sidewinder missiles, general-purpose bomb, cluster bombs, LAU-3A Launchers, flare and chaff dispensers and drop tanks.]]
The resulting EF-105F Wild Weasel III{{#tag:ref|The Wild Weasel IA and II designations referred to experimental conversions of F-105Ds and F-105Fs respectively which were used to evaluate various sensor and [[Electronic countermeasure]] (ECM) equipment. The Wild Weasel III used similar avionics to the Wild Weasel I F-100s.<ref name="Lake p31"/>|group=N}} (the EF designation was popularly used but unofficial<ref name="IAPR6 p135"/>) supplemented its sensors and electronic jamming equipment with [[AGM-45 Shrike]] anti-radiation missiles and conventional bombs, giving it an offensive capability lacking in the F-100F. The first of these aircraft flew on 15 January 1966<ref name="WoF18 p26">Davis 2000, p. 26.</ref> and they began arriving in Southeast Asia in May, flying their first mission on 6 June 1966,<ref name="IAPR6 p135"/> with five assigned to the 13th TFS at Korat RTAFB and six more to the 354th TFS at Takhli RTAFB.<ref name="Lake p31"/>

In a typical early mission, a single EF-105F would accompany one or two flights of F-105Ds to provide protection from enemy ground fire. While this strategy was effective in reducing F-105D losses, the Weasel aircraft suffered heavy casualties with five of the first 11 lost in July and August 1966. Attacks into high-risk environments saw the Weasels operating in "Iron Hand" hunter-killer flights of mixed single-seat and two-seat Thunderchiefs, suppressing sites during attacks by the strike force and attacking others en route.<ref name="WoF18 p26"/><ref name="Tech p53">Davis and Menard 1998, p. 53.</ref> In the fall of 1967, EF-105Fs began to be upgraded to the definitive Wild Weasel Thunderchief, the F-105G.<ref>Richardson 1992, pp. 38–39.</ref>

The F-105G incorporated a considerable amount of new SEAD-specific avionics, including an upgraded [[Radar Homing and Warning]] (RHAW) system which required a redesign of the wingtips. To free outboard hardpoints for additional weapons, the Westinghouse AN/ALQ-105 [[electronic countermeasures]] were permanently installed in two long blisters on the underside of the fuselage. Thirty aircraft were fitted with pylons to carry the [[AGM-78 Standard]] [[anti-radiation missile]]. On a typical mission, the F-105G carried two Shrikes on outboard pylons, a single Standard on an inboard pylon balanced by a {{convert|450|gal|L|abbr=on|sigfig=2}} fuel tank on the other side, and a {{convert|650|gal|L|abbr=on|sigfig=2}} centerline fuel tank.<ref>Knaack 1978, pp. 201-203.</ref>

===Costs===
{|class="wikitable" style="text-align:right;  width:630px;"
!!!F-105B!!F-105D!!F-105F/G
|-
|Unit [[Research and development|R&D]] cost|| colspan="3" style="text-align:center;"|2,716 prorated per aircraft
|-
|Airframe||4,914,016||1,472,145||1,524,000
|-
|Engine||328,797||244,412||290,000
|-
|Electronics||141,796||19,346||251,000
|-
|Armament||232,913||167,621||154,000
|-
|Ordnance||32,021||19,346||21,000
|-
|Flyaway cost||5,649,543||2,140,000 ||2,200,000
|-
|Modification costs by 1973||261,793||282,687||701,645<br /> plus 1,803 for F-105G conversion
|-
|Cost per flying hour||||1,020||1,020
|-
|Maintenance cost per flying hour||718||809||808
|-
|colspan = 4 | Notes: ''The costs above are in approximately 1960 [[United States dollar]]s and have not been adjusted for inflation.''<ref name=Knaack_p195,0,3>Knaack 1978, pp. 195, 200, 203.</ref> <!-- Approximately a seven-fold increase from 1960 to 2006 -->
|}

==Operational history==
===Introduction===
[[File:Republic F-105D-6-RE (SN 58-1762) refueling probe detail 060901-F-1234S-006.jpg|thumb|F-105D refueling probe detail. The -D model had two types of in-flight refueling equipment: a probe (for the drogue) and a receptacle (for the boom).]]

The F-105B entered USAF service with the [[Tactical Air Command]]'s [[335th Fighter Squadron|335th Tactical Fighter Squadron]] of the [[4th Fighter Wing|4th Tactical Fighter Wing]] in August 1958, although the squadron did not become fully operational until 1959.<ref name=Knaack_p193/> On 11 December 1959, an F-105B piloted by Brig Gen [[Joseph Harold Moore|Joseph Moore]] (commander of the 4th Tactical Fighter Wing) set a world record of {{convert|1216.48|mph|km/h|sigfig=4}} over a {{convert|62|mi|km|sigfig=2}} circuit.<ref name=Knaack_p195>Knaack 1978, p. 195.</ref><ref>Anderton 1983, p. 61.</ref> Difficulties with its [[avionics]] and the MA-8 [[fire-control system]] were experienced early on; typically the F-105 required 150 hours of maintenance for each flying hour. Most of these problems were addressed under ''Project Optimize''. The lack of spares resulted in the entire F-105B fleet being briefly grounded in 1960.<ref name=Knaack_p194>Knaack 1978, p. 194.</ref><ref name="AIAp86 p186-7">Peacock 1986, pp. 186–187.</ref> In 1964, modified F-105Bs with ballast replacing the cannon, fuselage and wing reinforcement for aerobatics, and the addition of a smoke generator, briefly flew with the [[United States Air Force Thunderbirds]] demonstration team. After only six shows, a fatal accident from overstressing the airframe led to the reintroduction of the F-100 Super Sabre.<ref name="IAPR6 p128-9">Davis 2002, pp. 128–129.</ref><ref name="Tech p43">Davis and Menard 1998, p. 43.</ref>

By 1964, the F-105B was relegated to USAF [[Air National Guard]] (ANG) squadrons.<ref name=Knaack_p195/><ref name="Tech p16">Davis and Menard 1998, p. 16.</ref> It was replaced in frontline service by the definitive F-105D whose advanced NASARR R-14A radar and AN/ASG-19 Thunderstick fire-control system gave it all-weather capability. The R-14A radar also added a [[Terrain-following radar|terrain-avoidance radar]] capability, while a completely new instrument panel was fitted, replacing dial-type instrument with vertical tape instruments which were easier to read in combat. In order to accommodate the new radar, with a much larger radar dish, the forward fuselage was redesigned, increasing overall length by {{convert|16|in|cm}}.<ref name="IAPR6 p129-0">Davis 2002, pp. 129–130.</ref><ref name="Tech p17-8">Davis and Menard 1998, pp. 17–18.</ref>

[[File:Republic F-105D 00474 SCUL 19.05.62 edited-2.jpg|thumb|Republic F-105D of 36 Tactical Fighter Wing based at Bitburg, West Germany, in 1962]]
The F-105D entered service with the 335th TFS in September 1960, although it was not fully operational on the F-105D until early 1961.<ref name="IAPR6 p130"/> The first overseas F-105 units formed in West Germany in 1961, with the [[36th Tactical Fighter Wing]] at [[Bitburg Air Base]] in May and the [[49th Tactical Fighter Wing]] at [[Spangdahlem Air Base]] in October. Both wings had a primary tactical nuclear strike role for [[NATO]].<ref name="IAPR6 p130"/> The F-105D was also deployed to the Pacific, with the [[18th Tactical Fighter Wing]] at [[Kadena Air Base|Kadena]] in [[Okinawa Island|Okinawa]] converting in 1962 and the [[8th Tactical Fighter Wing]] converting from 1963.<ref name="AIAp86 p188">Peacock 1986, p. 188.</ref>

Like the F-105B, the F-105D's early career was plagued with maintenance problems and in-flight failures.<ref name=Knaack_p197>Knaack 1978, p. 197.</ref> The origins of the nickname ''"Thud"'' were obscure; some claim that it stood for the sound of an F-105 crashing into the ground.<ref name="Tech p5">Davis and Menard 1998, p. 5.</ref> The entire F-105D fleet was grounded in December 1961 and then again in June 1962.<ref name="AIAp86 p188"/> Many of the issues were worked out during the production run and by 1964, early F-105Ds were upgraded with these fixes under Project ''Look Alike'', although engine failures and fuel system problems persisted until 1967.<ref>Knaack 1978, pp. 197-198.</ref><ref>Anderton 1983, p. 80.</ref>

[[File:Tactical Weapons Effects Tests U.S. Air Force F-100, F-104, F-105 Aircraft.webm|thumb|Declassified tactical weapons effects tests of the U.S. Air Force century series aircraft]]
Meanwhile, the USAF was gradually changing the anticipated F-105 mission from nuclear interdiction to conventional bombing. The ''Look Alike'' upgrades increased the aircraft's capacity from four to 16 conventional {{convert|750|lb|kg|abbr=on|sigfig=2}} bombs on underwing and fuselage centerline hardpoints and added the equipment to launch [[AGM-12 Bullpup]] air-to-ground missiles. In June 1961, an F-105D delivered {{convert|15430|lb|kg|abbr=on|sigfig=2}} of conventional bombs during a USAF test—at the time, a record for a single-engine aircraft with a payload three times heavier than American four-engine heavy bombers of World War II, such as the [[Boeing B-17 Flying Fortress]] and the [[Consolidated B-24 Liberator]], though aerial refueling would be required for long missions.<ref>Knaack 1978, pp. 198-199.</ref> One of the F-105Ds was named ''Memphis Belle II'' after the [[Memphis Belle (aircraft)|famed World War II B-17]].<ref name="F-105D">[https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/196054/republic-f-105d-thunderchief/ "Republic F-105D Thunderchief".]  ''National Museum of the US Air Force'', 20 December 2016.</ref>

===Vietnam War===
[[File:Republic F-105 Thunderchief - Vietnam War 1966.jpg|thumb|left|F-105s take off on a mission to bomb North Vietnam, 1966]]

In spite of a troubled early service life, the F-105 became the dominant attack aircraft early in the [[Vietnam War]]. The F-105 could carry more than twice the bomb load farther and faster than the F-100, which was used mostly in South Vietnam.<ref>[http://www.nasm.si.edu/collections/artifact.cfm?id=A19820064000 "Republic F-105D."] {{Webarchive|url=https://web.archive.org/web/20110402170946/http://www.nasm.si.edu/collections/artifact.cfm?id=A19820064000 |date=2 April 2011 }} ''National Air and Space Museum''. Retrieved: 30 June 2011.</ref> In a foreshadowing of its Wild Weasel role, the first F-105D combat mission of the war involved an attack on 14 August 1964 against an anti-aircraft artillery site on [[Plain of Jars|Plaine des Jarres]].<ref name="AIAp86 p189">Peacock 1986, p. 189.</ref><ref name="WoF18 p17-8">Davis 2000, pp. 17–18.</ref> This mission was carried out by aircraft of the 36th TFS, 6441st Tactical Fighter Wing deployed from [[Yokota Air Base]], Japan to [[Korat Royal Thai Air Force Base]], Thailand.<ref>[http://www.yokota.af.mil/library/factsheets/factsheet_print.asp?fsID=6819&page=1 "U.S. Air Force Fact Sheet 374th Airlift Wing: History."] {{webarchive|url=https://web.archive.org/web/20110928232650/http://www.yokota.af.mil/library/factsheets/factsheet_print.asp?fsID=6819&page=1 |date=28 September 2011 }} ''yokota.af.mil.'' Fact Sheet. Retrieved: 30 June 2011.</ref> The first Thunderchief lost in the war also occurred during this mission, although the pilot managed to return the aircraft to Korat.<ref name="AIAp86 p189"/><ref name="WoF18 p17-8"/> The first strike mission took place on 13 January 1965 with the destruction of the Ban Ken bridge in [[Laos]].<ref name="AIAp86 p189-0">Peacock 1986, pp. 189–190.</ref> In early 1965 additional F-105 squadrons were deployed to Korat and [[Takhli Royal Thai Air Force Base|Takhli]] air bases in Thailand. At the start of [[Operation Rolling Thunder]] in March 1965, large numbers of F-105Ds were shipped to these bases to participate in intense bombing missions.<ref>Davies 2010, pp. 21–23.</ref>

[[File:U.S. Air Force Republic F-105D Thunderchief shot down over North Vietnam, circa in the mid-1960s.jpg|thumb|A U.S. Air Force F-105D Thunderchief shot down over North Vietnam.]]
On 3 April 1965, a total of 79 aircraft, including 45 F-105 Thunderchiefs, were sent against the [[Thanh Hoa Bridge]], nicknamed "Dragon's Jaw".<ref>Sherwood 2004, p. 267.</ref> The next day, enemy MiGs were encountered during a second run upon the bridge; a total of eight [[Mikoyan-Gurevich MiG-17|MiG-17s]] faced 46 F-105s escorted by a [[Combat air patrol#CAP types|MiGCAP]] flight of 21 F-100 Super Sabres. The MiG-17s evaded the escorts using altitude and cloud cover, instead focusing upon the bomb-laden Thunderchiefs. Two Thunderchiefs were lost to the MiG-17s; a third, thought to be lost to ground fire, was later claimed by the North as downed by a MiG-17. One F-105 piloted narrowly escaped.<ref>Hillaker, Harry. [http://www.wingsoverkansas.com/profiles/article.asp?id=686 "Tribute To John R. Boyd."] {{Webarchive |url=https://web.archive.org/web/20110928201157/http://www.wingsoverkansas.com/profiles/article.asp?id=686 |date=28 September 2011 }} ''wingsoverkansas.com.'' Retrieved: 30 June 2011.</ref><ref>Sherwood 2004, p. 268.</ref> USAF Chief of Staff General [[John P. McConnell (general)|John P. McConnell]] was "hopping mad" to hear that two F-105s had been shot down by Korean War-era subsonic North Vietnamese MiGs.<ref>[https://web.archive.org/web/20110203152342/http://www.time.com/time/magazine/article/0,9171,841817,00.html#ixzz0r9PxRuDR "Armed Forces: How It Happened."] ''Time,'' 16 April 1965.</ref> The Thanh Hoa Bridge proved resistant to aerial bombing; multiple missions were flown to damage the bridge both by F-105s and U.S. Navy aircraft.<ref>Sherwood 2004, pp. 268-269.</ref>

On 24 July 1965, four U.S. Air Force McDonnell [[McDonnell Douglas F-4 Phantom II|F-4C Phantoms]] took part in an airstrike against the Dien Ben Phu munitions storage depot and the Lang Chi munitions factory west of Hanoi. One was shot down and three were damaged by SA-2 missiles.<ref name=thuds>{{Cite web |url=https://www.historynet.com/operation-spring-high-thuds-vs-sams.htm |title=Operation Spring High: Thuds vs. SAMs<!-- Bot generated title --> |access-date=28 February 2019 |archive-date=1 February 2019 |archive-url=https://web.archive.org/web/20190201171855/https://www.historynet.com/operation-spring-high-thuds-vs-sams.htm |url-status=live }}</ref> After two days, President Johnson gave the order to attack all known SA-2 positions which had been discovered outside the 30-mile exclusion zone. On the morning of 27 July, 48 F-105s participated in the Operation Spring High attack. But the Vietnamese knew U.S. aircraft were coming and set up many 23mm and 37mm anti-aircraft guns at the site. These anti-aircraft guns were lethal at close range and the Vietnamese shot down six aircraft, while more than half of the remaining U.S. aircraft suffered damage from ground fire. Both surface-to-air missile sites were devoid of missiles and equipment, and the Vietnamese had substituted white-painted bundles of [[bamboo]] for the real SA-2s. Operation Spring High destroyed two worthless targets at the cost of six aircraft and five pilots.<ref name=thuds />

In December 1966, the [[Vietnam People's Air Force]] (VPAF)'s MiG-21 pilots of the 921st Regiment claimed to have downed 14 F-105s without any losses.<ref>{{cite web |url=http://acepilots.com/vietnam/viet_aces.html |title=Vietnamese Aces - MiG-17 and MiG-21 pilots |publisher=Acepilots.com |access-date=9 August 2013 |archive-date=23 January 2013 |archive-url=https://web.archive.org/web/20130123111248/http://acepilots.com/vietnam/viet_aces.html |url-status=live }}</ref>

On a typical combat mission into North Vietnam, the F-105D carried two {{convert|450|gal|L|abbr=on|sigfig=2}} wing-mounted fuel tanks, a {{convert|390|gal|L|abbr=on|sigfig=2}} fuel tank in the bomb bay, and five {{convert|1000|lb|kg|abbr=on|sigfig=2}} or six {{convert|750|lb|kg|abbr=on|sigfig=2}} bombs, and required [[Aerial refueling|inflight refueling]] going to and sometimes returning from [[Hanoi]] {{convert|700|mi|km|abbr=on|sigfig=2}} distant. F-105s flying in the vicinity of Hanoi would routinely travel around mountainous terrain nicknamed ''[[Thud Ridge]]'' to evade the air defenses surrounding the city.<ref>Richardson 1992, pp. 28–30.</ref><ref>Broughton 2006, pp. 26-27.</ref> Colonel [[Jacksel M. Broughton|Jack Broughton]], an F-105 pilot in Vietnam, noted the demands of flying close to Hanoi gave "simply no room for error".<ref>Broughton 2006, p. 31.</ref>

[[File:Thud Ridge.jpg|thumb|upright=1.05|Location of the [[Thud Ridge]] ({{Coord|21|16|47|N|105|49|37|E}}) and the MiG airfield on its southern tip]]
On 11 August 1967, F-105Ds from 335th Tactical Fighter Squadron with support from F-105 Wild Weasels from 338th Tactical Fighter Squadron made the first of many successful attacks on the [[Long Bien Bridge|Paul Doumer bridge]] over the Red River.<ref>Davies 2010, pp. 50–51.</ref><ref>Sherwood 2004, p. 265.</ref> Flying low-altitude missions and conducting dive bombings forced the F-105s into range of North Vietnamese anti-aircraft guns, sometimes coming under heavy fire.<ref>Davis and Menard 1998, p. 73.</ref>

USAF F-105s were escorted by F-4s to protect them against enemy fighters. However, the Thunderchief was officially credited with 27.5 air-to-air victories against VPAF aircraft at the cost of 17 aircraft lost to enemy fighters (North Vietnamese pilots claimed to have shot down an additional 23 F-105s but none have been confirmed by USAF). All victories were against MiG-17s. Of these 24.5 were shot down with cannon fire (one victory was shared with an F-4), and three with [[AIM-9 Sidewinder]] missiles.<ref name="Futrell p157"/> One F-105F is unofficially credited with downing three MiGs—one by air-to-air missile, the second by cannon fire and the third by jettisoning the centerline rack full of bombs directly into the path of a surprised MiG.<ref>Davis and Menard 1998, p. 85.</ref>

On 31 May 1968, a dedication ceremony took place at the [[United States Air Force Academy]] to honor graduates who had served in Vietnam. An F-105, which had been assembled using parts from ten different F-105s that had seen service in Vietnam, was placed on permanent static display.<ref>{{cite web |url=http://jabara.usafalibrary.com/files/6688_FilePath.pdf |title=Thunderchief Worldwide Report on Republic's F-105 Fighter-Bomber |work=12o'clock low |date=June 1968 |volume=Vol. III, (№ 10) |access-date=17 June 2014 |via=jabara.usafalibrary.com |archive-date=14 July 2014 |archive-url=https://web.archive.org/web/20140714194735/http://jabara.usafalibrary.com/files/6688_FilePath.pdf |url-status=live }}</ref> The ceremony included the entire cadet wing, the superintendent and commandant of cadets of the USAFA, a representative of Republic Aircraft, members of the press, among others. To conclude the ceremony, a flight of four F-105s from [[McConnell Air Force Base|McConnell AFB]] were to fly over in formation at 1,000 feet above the ground and then fly over singly at 250 feet. The formation portion happened as planned. But the flight leader, Lt Col James "Black Matt" Matthews, came back for the single-file pass and exceeded the speed of sound at less than 100 feet. The ensuing [[sonic boom]] broke hundreds of windows and fifteen people sustained cuts.<ref>{{cite news |author=Herts, Ray |url=http://www.usafa68.org/history/ch5.htm |title=Sonic Boom in Fly-Over Damages Academy Buildings |work=[[Colorado Springs Gazette-Telegraph]] |date=1 June 1968 |access-date=17 June 2014 |via=usafa68.org |pages=1, 16 |format=scan |url-status=dead|archive-url=https://web.archive.org/web/20140714193853/http://www.usafa68.org/history/ch5.htm |archive-date=14 July 2014 |df=dmy-all }}</ref>

====Medal of Honor recipients====
Two Wild Weasel pilots received the [[Medal of Honor]]:
* USAF [[Captain (United States)|Captain]] [[Merlyn H. Dethlefsen]] was awarded the [[Medal of Honor]] and Capt [[Kevin A. Gilroy|Kevin "Mike" Gilroy]] the [[Air Force Cross (United States)|Air Force Cross]] for an F-105F Wild Weasel mission on 10 March 1967, flying F-105F, [[United States military aircraft serials|serial number]] ''63-8352''.<ref>{{cite magazine|url=https://www.airandspaceforces.com/article/0206courage/|title=Calculated Courage at Thai Nguyen|last=Correll|first=John T.|volume=89|issue=2|date=February 2006|access-date=24 March 2006|magazine=[[Air & Space Forces Magazine]]|archive-url=https://web.archive.org/web/20250623185441/https://www.airandspaceforces.com/article/0206courage/|archive-date=23 June 2025|url-status=live}}</ref> After their aircraft was damaged by ground fire, Dethlefsen and Gilroy elected to stay in the skies above the steel works at Thai Nguyen until the surface-to-air missile site was found and destroyed.<ref>[[Merlyn Hans Dethlefsen|Dethlefsen, Colonel Merlyn H.]] (17 July 2012) [https://archive.today/20120717031801/http://www.af.mil/information/heritage/person.asp?dec=1960&pid=123006512 "Col. Merlyn H. Dethlefsen."] ''af.mil.'' Retrieved: 30 June 2011. via archive.is</ref>
* USAF Captain [[Leo K. Thorsness]] was awarded the Medal of Honor and Capt Harold Johnson the Air Force Cross for an F-105F Wild Weasel mission on 19 April 1967, flying F-105F, [[United States military aircraft serials|serial number]] ''63-8301''. Thorsness and Johnson protected an attempted rescue of another Wild Weasel crew that had been shot down, in the process destroying two MiG-17s. After running out of ammunition, Thorsness and Johnson continued to act as decoys to draw the MiGs away from the rescue aircraft.<ref>{{cite magazine|url=https://www.airandspaceforces.com/article/valor-wild-wild-weasel/|title=Valor: Wild, Wild Weasel|last=Frisbee|first=John L.|date=April 1985|volume=68|issue=4|magazine=[[Air & Space Forces Magazine]]|archive-url=https://web.archive.org/web/20250817203440/https://www.airandspaceforces.com/article/valor-wild-wild-weasel/|archive-date=17 August 2025|url-status=live|access-date=24 March 2006}}</ref>

===Phase-out and retirement===
[[File:Hill F-105 24-ship formation.jpg|thumb|The 24-ship flyover formation, Diamonds on Diamonds, flew at the F-105 retirement at [[Hill Air Force Base]], Utah on 4 June 1983]]
As production of F-105s had ended, the type was replaced in the Vietnam War by other aircraft, primarily the F-4 Phantom II.<ref>Richardson 1992, pp. 40–41.</ref> In October 1970, the [[355th Fighter Wing|355th Tactical Fighter Wing]], which was based at Takhli RTAFB, Thailand, and was the last F-105D unit in Southeast Asia, began to return to the U.S. The F-105G Wild Weasel versions soldiered on until the end of the war. They were gradually replaced by F-4G Wild Weasel IVs.<ref>Richardson 1992, pp. 41–45.</ref>

The Thunderchief was rapidly withdrawn from USAF service after the end of the Vietnam War. Of the 833 F-105s built, a combined 395 F-105s were lost in Southeast Asia, including 334 (296 F-105Ds and 38 two-seaters) lost to enemy action and 61 lost in operational accidents.<ref>Hobson 2001, p. 269.</ref><ref name="IAPR6 p149">Davies 2002, p. 149.</ref> Following the war the USAF began transferring the remaining aircraft to [[Air Force Reserve Command|Air Force Reserve]] (AFRES) and Air National Guard (ANG) units. By the late 1970s, these aging Thunderchiefs were becoming difficult to maintain.<ref>Richardson 1992, pp. 44–45.</ref> The last F-105Gs with the [[128th Airborne Command and Control Squadron|128th Tactical Fighter Squadron]] of the [[Georgia Air National Guard|Georgia ANG]] were retired on 25 May 1983.<ref>Davis and Menard 1998, p. 63.</ref> The last flight of the F-105 Thunderchief was by the AFRES [[466th Fighter Squadron|466th Tactical Fighter Squadron]] with F-105Ds on 25 February 1984.<ref>Davis and Menard 1998, p. 99.</ref>

==Variants==
[[File:Republic YF-105A Thunderchief 3-view line drawing.png|thumb|A 3-view line drawing of the YF-105A]]
[[File:Republic F-105 variants drawings.png|thumb|drawings of F-105 variants]]
;YF-105A
:Two pre-production prototypes with P&W J57 engine model.<ref name=Donald_Encyclo>Donald 1997, p. 773.</ref>
;YF-105B
:Four pre-production aircraft with P&W J75 engine.<ref name=Donald_Encyclo/>
;F-105B
:Initial production model with AN/APN-105 navigational radar, 71 built.<ref name=Donald_Encyclo/>
;JF-105B
:Test aircraft built from re-allocated RF-105B airframes; three built.<ref name=Donald_Encyclo/>
;RF-105B
:Proposed reconnaissance version of the F-105B; none built. Three were ordered but completed as JF-105Bs.<ref name=Donald_Encyclo/>
;F-105C
:Proposed dual-control trainer; canceled in 1957, none built.<ref name="AIAp86 p186"/>
;F-105D
:The definitive production model, all-weather capability because of advanced avionics, including AN/APN-131 navigational radar; 610 built.<ref name="IAPR6 p129-0"/><ref name="AIAp86 p187">Peacock 1986, p. 187.</ref>
;RF-105D
:Proposed reconnaissance version of the F-105D; none built.<ref name=Donald_Encyclo/>
;F-105E
:Proposed trainer version of F-105D; cancelled in 1959, none completed.<ref name="IAPR6 p129">Davis 2002, p. 129.</ref>
;F-105F
:Two-seat trainer version of F-105D with lengthened forward fuselage. It was fully combat-capable and had dual controls, taller fin, and increased takeoff weight; its first flight took place on 11 June 1963. A total of 143 were built.<ref name=Richardson_p20/>
;EF-105F
:Initial designation for a [[Wild Weasel]]/[[Suppression of Enemy Air Defenses|Defense suppression]] version, 54 converted from F-105Fs.<ref name=Donald_Encyclo/>
;F-105G
:Two-seat Wild Weasel, improved version of the EF-105F.<ref name=Richardson_p28_38/>
;F-105H
:Proposed upgraded two-seat variant based on the F-105F with a larger wing with folding wing tips, nose, larger vertical tail, larger stabiliator, and modified landing gear. Never built.<ref>Anderton 1983, p. 187.</ref>

==Operators==
[[File:F-105D Wings Museum Colo.JPG|thumb|F-105D 60-0508, formerly with 49th TFW, at Wings Over the Rockies Museum, Denver, Colorado]]
{{See also|List of F-105 units of the United States Air Force}}

;{{USA}}
* [[United States Air Force]]
* [[United States Air Force Thunderbirds]]
* [[Air Force Reserve Command|Air Force Reserve]]
* [[Air National Guard]]
{{Clear}}

==Surviving aircraft==
{{Main|List of surviving Republic F-105 Thunderchiefs}}

==Specifications (F-105D)==
{{multiple image
 |total_width = 500
 | image1 = Republic F-105B Thunderchief 3-view line drawing.png
 | alt1 = 3-view line drawing of the Republic F-105B Thunderchief
 | caption1 = 3-view line drawing of the Republic F-105B Thunderchief
 | image2 = Republic F-105F Thunderchief 3-view line drawing.png
 | alt2 = 3-view line drawing of the Republic F-105F Thunderchief
 | caption2 = 3-view line drawing of the Republic F-105F Thunderchief
}}

{{Aircraft specs
|ref= ''The Great Book of Fighters'',<ref name=Green/> ''Quest for Performance'',<ref>Loftin, L.K. Jr. [http://www.hq.nasa.gov/pao/History/SP-468/cover.htm "Quest for Performance: The Evolution of Modern Aircraft: NASA SP-468".] {{Webarchive|url= https://web.archive.org/web/20060613210139/http://www.hq.nasa.gov/pao/History/SP-468/cover.htm |date= 13 June 2006}} ''NASA''. Retrieved: 22 April 2006.</ref> ''U.S. Standard Aircraft Characteristics: F-105D-31'',<ref>{{cite web |url= http://www.alternatewars.com/SAC/F-105D-31_Thunderchief_SAC_-_June_1970.pdf |title= Standard Aircraft Characteristics: F-105D-31 |publisher= US Air Force |date= June 1970 |access-date= 14 December 2018 |archive-date=29 February 2020 |archive-url=https://web.archive.org/web/20200229045849/http://www.alternatewars.com/SAC/F-105D-31_Thunderchief_SAC_-_June_1970.pdf |url-status=live}}</ref> ''Jane's All the World's Aircraft 1969-70''<ref name=JAWA69-70>{{cite book |title= Jane's All the World's Aircraft 1969-70 |year= 1969 |publisher= Sampson Low, Marston & Company |location= London, UK |edition= 60th |editor1-last= Taylor |editor1-first= John W.R. |page= 325}}</ref>
|prime units?= kts
<!--    General characteristics
-->
|crew= 1 (F-105F: 2<ref name=JAWA69-70/>)
|length ft= 64
|length in= 4+3/4
|length note=
|span ft= 34
|span in= 11+1/4
|span note=
|height ft= 19
|height in= 8
|height note=
|wing area sqft= 385
|wing area note=
|aspect ratio= 3.18
|airfoil= root: [[NACA airfoil|NACA 65A005.5]]; tip: [[NACA airfoil|NACA 65A003.7]]<ref name="Selig">{{cite web |last1= Lednicer |first1= David |title= The Incomplete Guide to Airfoil Usage |url= https://m-selig.ae.illinois.edu/ads/aircraft.html |website= m-selig.ae.illinois.edu |access-date= 16 April 2019 |archive-date= 26 March 2019 |archive-url= https://web.archive.org/web/20190326174850/https://m-selig.ae.illinois.edu/ads/aircraft.html |url-status= live}}</ref>
|empty weight lb= 26,855
|empty weight note=
|gross weight lb= 35,637
|gross weight note=
|max takeoff weight lb= 52,838
|max takeoff weight note=
|fuel capacity= {{cvt|770|USgal|impgal l}} in three flexible fuselage tanks <big>+</big> {{cvt|390|USgal|impgal l}} weapon-bay tank, with provision for 1 × {{cvt|650|USgal|impgal l}} or {{cvt|750|USgal|impgal l}} centerline drop tank and 2 × {{cvt|450|USgal|impgal l}} underwing drop tanks; Total maximum fuel {{cvt|2810|USgal|impgal l}}<ref name=JAWA69-70/>
|more general= <br>
* '''[[Zero-lift drag coefficient]]:''' C<sub>D</sub> 0.0173
* '''[[zero-lift drag coefficient|Drag area:]]''' {{cvt|6.65|sqft|1}}
<!--   Powerplant
-->
|eng1 number= 1
|eng1 name= [[Pratt & Whitney J75-P-19W]]
|eng1 type= afterburning turbojet engine
|eng1 lbf= 14,300
|eng1 note= {{cvt|26500|lbf|kN|2}} with afterburning and [[Water injection (engines)|water injection]]<ref name=JAWA69-70/>
<!--   Performance
-->
|max speed kts= 1,210
|max speed note= / Mach 2.1 at {{cvt|35000|ft}}
|cruise speed kts=
|cruise speed note=
|stall speed kts=
|stall speed note=
|never exceed speed kts=
|never exceed speed note=
|range nmi=
|range note=
|combat range nmi= 676
|combat range note=
|ferry range nmi= 1,917
|ferry range note=
|endurance=<!-- if range unknown -->
|ceiling ft= 48,500
|ceiling note=
|g limits=<!-- aerobatic -->
|roll rate=<!-- aerobatic -->
|climb rate ftmin= 38,500
|climb rate note=
|time to altitude= {{cvt|35000|ft}} in one minute and 42 seconds
|lift to drag= 10.4
|wing loading lb/sqft= 93
|wing loading note=
|fuel consumption lb/mi=
|thrust/weight= 0.74
|more performance=
<!--   Armament
-->
|guns= 1 × [[20 mm caliber|20 mm (0.787 in)]] [[M61A1 Vulcan]] [[Gatling gun#M61 Vulcan, Minigun, and other designs|6-barreled Gatling cannon]], 1,028 rounds
|hardpoints= 5 total: 4 × under-wing, 1 × centerline pylon stations plus an internal [[bomb bay]]
|hardpoint capacity= up to {{convert|14000|lb|kg|abbr=on|sigfig=2}} of ordnance
|hardpoint rockets= <br>
*** LAU-32/LAU-59 rocket pods with 7 × [[Folding-Fin Aerial Rocket|FFAR]]s each
|hardpoint missiles= <br>
*** [[AIM-9 Sidewinder]] air-to-air missiles
*** [[AGM-12 Bullpup]] air-to-surface missiles
*** [[AGM-45 Shrike]] anti-radiation missiles
|hardpoint bombs= <br>
*** [[M117 bomb|M117]] and [[Mark 80|Mark 80 series]] of general-purpose bombs
*** [[Mark 118 bomb|M118 demolition bombs]]
*** Nuclear weapons [[B28 nuclear bomb|B28]], [[B43 nuclear bomb|B43]] stored internally and [[B57 nuclear bomb|B57]], [[B61 nuclear bomb|B61]]
*** [[Cluster munition]]s of various types, including [[CBU-24]]

|avionics=
* NASARR R-14A [[radar]]
* AN/ASG-19 Thunderstick [[fire control system]]
* AN/ARN-85 [[LORAN]] (AN/ARN-92 in ''Thunderstick II''-modified aircraft)
}}

==Video resources==
<gallery class="center" widths="220">
File:Mach Of The Thunderchief.webm|''"Mach of the Thunderchief"'' Republic Aircraft Corporation promotional film.
File:USAF There Is a Way F-105 Thunderchief in Vietnam War Korat AFB.webm|''"There Is A Way"''' Official [[USAF]] promotional film reel.
File:Fod Foreign Object Damage of Aircraft F-105 Thunderchief.webm|F-105 Foreign-Object Damage (FOD) management USAF informational film reel
File:F105 Armamant Capability and Spin Test.webm|''"F-105 Armament Capability and Spin Tests"'' Republic Aircraft Corporation promotional film.
File:USAF Air Strikes in North Vietnam in 1966 Bombing of Hanoi.webm|''"The Bombing of Hanoi"'' (1966). USAF information film reel.
File:Air Strikes & Dogfights in Vietnam Highlight Reel F-105 F-4.webm|Air-strikes & dogfights in Vietnam - USAF silent film reel.
</gallery>
==See also==
{{aircontent
|related=
* [[Republic F-84F Thunderstreak]]
|similar aircraft=
* [[Blackburn Buccaneer]]
* [[Nanchang Q-5]]
* [[Sukhoi Su-7]]
* [[Sukhoi Su-17]]
|lists=
* [[List of fighter aircraft]]
* [[List of military aircraft of the United States]]
|see also=
* [[Century Series]]
* [[Thud Ridge]]
}}

==References==
===Notes===
{{Reflist|group=N}}

===Citations===
{{Reflist|30em}}

===Bibliography===
{{Refbegin}}
* {{cite book |last=Anderton |first=David |title=Republic F-105 Thunderchief |location=Oxford, UK |publisher=Osprey Publishing |date=1983 |isbn=0-85045-530-8}}
* {{cite book |last1=Angelucci |first1=Enzo |first2=Peter M. |last2=Bowers |author-link2=Peter M. Bowers |title=The American Fighter |location=Sparkford, UK |publisher=Haynes Publishing |date=1987 |isbn=0-85429-635-2}}
* {{cite book |last=Archer |first=Robert D. |title=The Republic F-105 "Thunderchief": The Story of Republic's Mach 2 Strike Fighter in Peace and at War |location=Fallbrook, California |publisher=Aero Publishers Inc. |date=1969}}
* {{Cite book |title=Thud Ridge |last=Broughton |first=Jack |author-link=Jacksel M. Broughton |publisher=MBI Publishing Company |location=St. Paul, Minnesota |year=2006 |isbn=978-0-85979-116-8 |url=https://books.google.com/books?id=zI33eyMCenQC }}{{Dead link|date=August 2024 |bot=InternetArchiveBot |fix-attempted=yes }}
* {{cite book |last=Crosby |first=Francis |title=Fighter Aircraft |location=London |publisher=Lorenz Books |date=2002 |isbn=0-7548-0990-0}}
* {{cite book |last=Davies |first=Peter E. |title=F-105 Thunderchief Units of the Vietnam War (Osprey Combat Aircraft #84) |location=Oxford, UK |publisher=Osprey Publishing Limited |date=2010 |isbn=978-1-84603-492-3}}
* {{cite magazine |last=Davis |first=Larry |title=F-105 in Southeast Asia |magazine=Wings of Fame |volume=18 |date=2000 |location=London |publisher=Aerospace Publishing |pages=16–37 |isbn=1-86184-061-6 |issn=1361-2034}}
* {{cite magazine |last=Davis |first=Larry |title=Warplane Classic: Republic F-105 Thunderchief |magazine=International Air Power Review |volume=6 |date=2002 |pages=120–155 |location=Norwalk, Connecticut |publisher=AIRtime Publishing |isbn=1-880588-46-3 |issn=1473-9917}}
* {{cite book |last1=Davis |first1=Larry |first2=David |last2=Menard |title=Republic F-105 Thunderchief (Warbird Tech Series, Vol. 18) |location=North Branch, Minnesota |publisher=Specialty Press |date=1998 |isbn=1-58007-011-6}}
* {{cite book |editor-last=Donald |editor-first=David |title=The Complete Encyclopedia of World Aircraft |location=New York |publisher=Barnes & Noble Books |date=1997 |isbn=0-7607-0592-5}}
* {{cite book |last1=Dorr |first1=Robert F. |first2=Chris |last2=Bishop |title=Vietnam Air War Debrief |location=London |publisher=Aerospace Publishing |date=1996 |isbn=1-874023-78-6}}
* {{cite book |last1=Futrell |first1=R. Frank |url=http://www.afhso.af.mil/shared/media/document/AFD-100921-010.pdf |title=Aces and Aerial Victories: The United States Air Force in Southeast Asia, 1965-1973 |archive-url=https://web.archive.org/web/20111127142355/http://www.afhso.af.mil/shared/media/document/AFD-100921-010.pdf |archive-date=27 November 2011 |location=Washington DC |publisher=Office of Air Force History and the Albert F. Simpson Historical Research Center |date=1976 |isbn=0-89875-884-X }}
* {{cite book |last1=Green |first1=William |first2=Gordon |last2=Swanborough |title=The Great Book of Fighters |location=St. Paul, Minnesota |publisher=MBI Publishing |date=2001 |isbn=0-7603-1194-3}}
* {{cite book |last1=Higham |first1=Robin |first2=Carol |last2=Williams |title=Flying Combat Aircraft of USAAF-USAF (Vol.1) |location=Rockville, Maryland |publisher=Air Force Historical Foundation |date=1975 |isbn=0-8138-0325-X}}
* {{cite book |last=Hobson |first=Chris |title=Vietnam Air Losses, USAF, USN, USMC, Fixed-Wing Aircraft Losses in Southeast Asia 1961–1973 |location=North Branch, Minnesota |publisher=Specialty Press |date=2001 |isbn=1-85780-115-6}}
* {{cite book |last=Jenkins |first=Dennis R. |title=F-105 Thunderchief: Workhorse of the Vietnam War |location=New York |publisher=McGraw-Hill |date=2000 |isbn=0-07-135511-1}}
* {{cite book |last1=Jenkins |first1=Dennis R. |first2=Tony R. |last2=Landis |title=Experimental & Prototype U.S. Air Force Jet Fighters |location=North Branch, Minnesota |publisher=Specialty Press |date=2008 |isbn=978-1-58007-111-6}}
* {{cite book |last=Kinzey |first=Bert |title=F-105 Thunderchief |location=Fallbrook, California |publisher=Aero Publishers Inc. |date=1982 |isbn=0-8168-5020-8}}
* {{Cite book |last=Knaack |first=Marcelle Size |url=https://books.google.com/books?id=145BAAAAIAAJ |title=Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1 Post-World War II Fighters 1945–1973 |location=Washington DC |publisher=Office of Air Force History |year=1978 |isbn=0-912799-59-5 |archive-date=3 March 2016 |archive-url=https://web.archive.org/web/20160303182633/http://www.afhso.af.mil/shared/media/document/AFD-100526-027.pdf |oclc=834250508 }}
* {{cite magazine |last=Lake |first=Jon |title=Classics Compared: F-105G & F-16CJ |magazine=Air International |volume=66 |number=2 |date=February 2004 |pages=30–39 |issn=0306-5634}}
* {{cite book |last=Neubeck |first=Ken |title=F-105 Thunderchief in Action |location=Carrollton, Texas |publisher=Squadron/Signal Publications |date=2002 |isbn=0-89747-447-3}}
* {{cite book |last=Neubeck |first=Ken |title=F-105 Thunderchief Walk Around |location=Carrollton, Texas |publisher=Squadron/Signal Publications |date=2000 |isbn=0-89747-418-X}}
* {{cite magazine |last=Peacock |first=Lindsay |title=The Thud ... Republic's Last Fighter |magazine=[[Air International]] |volume=30 |number=4 |date=April 1986 |pages=185–194, 206–207 |issn=0306-5634}}
* {{cite book |last=Price |first=Alfred |title=The History of US Electronic Warfare, Volume III: Rolling Thunder Through Allied Force–1964 to 2000 |location=New York |publisher=The Association of Old Crows |date=1989 |isbn=0-9703794-0-4}}
* {{cite book |url=https://books.google.com/books?id=Y6ylVunIVVwC |title=Republic F-105 Thunderchief Pilot's Flight Operating Instructions |location=Los Angeles |publisher=Persiscope Films LLC, originally published by the United States Air Force |date=2008 |isbn=978-1-935327-36-3 }}
* {{cite book |last=Richardson |first=Doug |title=Republic F-105 Thunderchief (Classic Warplanes) |date=1992 |location=New York |publisher=Smithmark Publishers Inc. |isbn=0-8317-1410-7}}
* {{cite book |last=Sherwood |first=John Darrell |url=https://books.google.com/books?id=4SuRjGKxQrAC |title=Afterburner: Naval Aviators and the Vietnam War |location=New York |publisher=NYU Press |date=2004 |isbn=0-8147-9842-X }}
* {{cite book |last=Stoff |first=Joshua |title=The Thunder Factory: An Illustrated History of the Republic Aviation Corporation |location=London |publisher=Arms & Armour Press |date=1990 |isbn=1-85409-040-2}}
* {{cite book |author-link=John W. R. Taylor |last=Taylor |first=John W. R. |title=Jane's All The World's Aircraft 1966–67 |location=London |publisher=Sampson Low, Marston & Company |date=1966}}
* {{cite book |last=Toperczer |first=Istvan |title=MiG-17 and MiG-19 Units of the Vietnam War |location=Oxford, UK |publisher=Osprey Publishing |date=2001 |isbn=1-84176-162-1}}
{{Refend}}

==External links==
{{Commons|F-105 Thunderchief}}
{{Wikisourcecat|Vietnam War|Audio recordings and transcripts with comments of actual F-105 Wild Weasel combat missions over Vietnam.}}

* [https://web.archive.org/web/20071224112550/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2314 USAF Museum F-105D Factsheet] and [https://web.archive.org/web/20071224112559/http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2315 USAF Museum F-105F/G Factsheet] on nationalmuseum.af.mil
* {{usurped|1=[https://web.archive.org/web/20020221191640/http://www.vectorsite.net/avf105.html Republic F-105 Thunderchief on Greg Goebel's AIR VECTORS]}}
* [https://web.archive.org/web/20150706032820/http://www.talkingproud.us/Military/Military/F105.html The F-105 Thud, a legend flown by legends] on talkingproud.us
* [http://www.burrusspta.org/thud.html Craig Baker's F-105 Site] {{Webarchive|url=https://web.archive.org/web/20090427120016/http://www.burrusspta.org/thud.html |date=27 April 2009 }} on burrusspta.org
* [https://web.archive.org/web/20091027002622/http://geocities.com/Pentagon/7002/ Republic F-105 Thunderchief In Combat] Thud Ridge Web, via web.archive.org
* [http://break-left.org/air/f-105.html F-105 Thunderchief page on break-left.org] {{Webarchive|url=https://web.archive.org/web/20130827020614/http://break-left.org/air/f-105.html |date=27 August 2013 }}
* [http://www.primeportal.net/hangar/bill_spidle2/f-105d_60-0500/ F-105 Thunderchief Walk Around on primeportal.net]
* [http://www.aerospaceweb.org/aircraft/bomber/f105/ F-105 profile on Aerospaceweb.org]
* [https://archive.org/details/twenty-five_hour_day ''Twenty-five hour day''] [https://archive.org/movies/thumbnails.php?identifier=twenty-five_hour_day (thumbnails)]; film primarily covering an F-105 attack over North Vietnam; plenty of Thud footage, and coverage of the support required for such an operation 
* [https://web.archive.org/web/20071025101707/http://www.aero-web.org/locator/manufact/republic/f-105.htm List of F-105 Thunderchiefs on display in the US on aero-web.org]
* {{webarchive |url = https://web.archive.org/web/20150705183022/http://www.flightglobal.com/pdfarchive/view/1959/1959%20-%202858.html |date = 5 July 2015 |title = "Only Republic's F-105 Has it All!" |nolink=y}}, a 1959 ''Flight'' advertisement for the F-105. flightglobal.com
* [https://www.youtube.com/watch?v=LNeP9OixQrY ''There Is A Way''], documentary on the 421st TFS "Fighting Cavaliers" who flew from Korat, via YouTube

{{Republic aircraft}}
{{USAF fighters}}
{{USAF system codes}}
{{Century Series}}
{{Authority control}}

[[Category:1950s United States fighter aircraft|Republic F-105 Thunderchief]]
[[Category:Aircraft first flown in 1955]]
[[Category:Mid-wing aircraft]]
[[Category:Republic aircraft|F-105]]
[[Category:Second-generation jet fighters]]
[[Category:Single-engined jet aircraft]]
[[Category:Aircraft with retractable tricycle landing gear]]