Il Grumman F6F Hellcat

Il Grumman F6F Hellcat fu sviluppato come caccia standard della Marina statunitense nella seconda guerra mondiale. Entrò in servizio nel 1943 e rimase il velivolo più importante dell'US Navy sino alla fine del conflitto.

Storia

Durante il precedente programma del Grumman F4F Wildcat la Grumman giunse alla concezione dell'ala monoplana, nonostante in origine anche questo aereo fosse biplano. Tuttavia in pochi anni il progresso aeronautico fece capire che il nuovo prodotto delle "Grumman Ironworks" ("Ferriere Grumman", per via della robustezza delle macchine prodotte) doveva essere potenziato. Dopo aver tentato di riprogettare il velivolo con motorizzazioni più potenti da 1.400-1.700 CV ci si accorse che gli obiettivi erano così difficili da raggiungere che si preferì ripartire con un progetto nuovo. Tra la metà del 1941 e un anno dopo il disegno fu aggiustato in ogni dettaglio e il prototipo decollò poco dopo la battaglia delle Midway. Le opzioni erano diverse, come quella con il motore da 1.700 CV, ma dopo i colloqui con i piloti i progettisti arrivarono alla conclusione che era necessario il motore più potente disponibile. Il prototipo giunse alla produzione di serie in maniera estremamente veloce e alla fine del 1942 10 aerei erano stati consegnati.

Progettazione e caratteristiche

L'Hellcat aveva una struttura robusta, dal peso di circa 4.000 chili a vuoto, il doppio dei primi Wildcat; il rapporto potenza-peso non era pari al predecessore, e anche il carico alare, oltre 182 chili per metro quadro, era di molto superiore.

La struttura era convenzionale, con l'ala bassa, la maggiore originalità del progetto, con una struttura trilongherone e 5 sezioni differenti, di cui le due esterne ripiegabili. Le superfici di coda, molto squadrate, erano metalliche rivestite in tela.

L'apparecchio originale era da superiorità aerea e caccia di scorta; il suo tempo di salita a 7.600 m era di circa 15 minuti, piuttosto elevato, mentre l'autonomia senza carico bellico, grazie ai quasi 900 litri, era di circa 1.700 km, oltre 2.600 con serbatoio aggiuntivo. Il tutto a velocità "economiche" di circa 270 km/h, tanto che l'autonomia oraria arrivava a circa 10 ore.

Il motore R-2.800 disponeva di turbocompressore e dispositivi ad iniezione d'acqua per ottenere in potenza aggiuntiva circa il 10% del valore nominale. Blindature per 96, poi 110 chili, furono installate nei punti vitali (posto di pilotaggio e circuito dell'olio) mentre il serbatoio era autostagnante ma non pressurizzato.

L'armamento era di 6 mitragliatrici Browning M2 con 2.400 colpi. Inizialmente non erano previsti armamenti per l'attacco al suolo, solo un serbatoio aggiuntivo. In seguito furono installati agganci per bombe da 227–454 kg.

Il velivolo inoltre era dotato di radiogoniometro, apparato radio ricetrasmittente di elevata potenza ed elica metallica tripala a giri costanti.

Impiego

Durante la guerra

Giunto ai reparti all'inizio del 1943, l'Hellcat ebbe il suo battesimo del fuoco alle isole Marcus nell'agosto. In quel periodo molte portaerei statunitensi erano state distrutte e quelle nuove stentavano ad entrare in servizio, e il velivolo predecessore aveva troppe difficoltà a battersi alla pari con i giapponesi, in servizio adesso in modelli migliorati.

Il nuovo caccia fu prodotto in 2.545 esemplari durante il 1943, 6.139 nel 1944 e 3.578 nel 1945. L'Hellcat sostituì il Wildcat dapprima sulle portaerei maggiori, poi anche su quelle di scorta e leggere. Le missioni all'inizio si rivelarono piuttosto difficili dato che gli avversari sui caccia Mitsubishi A6M "Zero" erano ancora temibili e sufficientemente esperti. Tuttavia in pochi mesi l'esperienza, il livello d'addestramento oltre che la superiorità tecnica passarono tutte dalla parte statunitense. Nel 1944 alcune terribili battaglie tolsero ai giapponesi ogni speranza di arginare gli americani. La prima fu l'incursione sulla potente base di Truk.

Quando si tennero test comparativi con uno Zero 52 catturato, essi rivelarono che l'Hellcat era più veloce dello Zero a ogni quota. Inoltre lo superava (di poco) in cabrata al di sopra dei 4.200 metri e aveva una velocità di rollio superiore a velocità maggiori dei 378 km/h. Il caccia giapponese poteva facilmente superare in virata l'Hellcat a basse velocità e aveva una velocità ascensionale leggermente superiore a quote inferiori ai 4.200 metri. Il rapporto sui test concludeva: “Non ingaggiare duelli con lo Zero 52. Non seguirlo in un looping o in un half-roll. In caso di attacco, utilizzare la vostra superiore potenza e velocità per impegnare combattimento nel momento più favorevole. Per fuggire da uno Zero 52, compiere una rovesciata e scendere in picchiata con una veloce virata.”

Nel giugno di quell'anno, gli Stati Uniti sconfissero ancora il Giappone nella Battaglia del Mare delle Filippine, passata alla storia come "Il tiro al tacchino delle Marianne". I nipponici persero 400 aeroplani e 3 portaerei anche se solo una fu affondata dagli aerei americani (le altre da sommergibili). Furono gli Hellcat a causare i danni maggiori: distrussero la maggior parte degli aerei, abbattuti mentre cercavano in varie ondate di raggiungere le formazioni americane, forti di almeno 9 portaerei principali (contro le 5 avversarie).

Il potere aereo giapponese basato a terra combinato con quello navale avrebbe potuto essere sufficiente per controbilanciare quello statunitense, ma la flotta americana non fu scoperta in tempo utile per poterla contrattaccare e gli aerei attaccarono gli aeroporti giapponesi bombardando le loro installazioni fino a distruggerle quasi totalmente. Anche in questa azione iniziale gli Hellcat ottennero numerosissime vittorie. A quel punto rimasero solo gli aerei sulle portaerei, ma due di queste furono silurate dai sottomarini, tra cui la Taiho, l'unica portaerei giapponese dotata di ponte di volo corazzato (che in questo caso, a differenza di quanto sarebbe avvenuto con i bombardieri in picchiata a Midway, non servì altro che a zavorrarla). Gli aerei giapponesi attaccarono inizialmente fuori dal raggio d'azione USA, ma individuate al radar, le 4 ondate furono abbattute una dietro l'altra.

L'enorme sproporzione tra perdite americane (una ventina di aerei) e giapponesi (circa 350) provò la superiorità degli F6F sui caccia A6M avversari, oltretutto aggravata dall'addestramento insufficiente, da scorte di carburante troppo limitate per consentire un buon grado di preparazione, sia perché quasi tutti i più esperti piloti da caccia della Marina erano caduti in battaglia. Aver logorato gli stormi da combattimento in azioni belliche combattute sopra Rabaul e Guadalcanal, senza usarli dalle portaerei per eseguire attacchi strategici lasciò i giapponesi con un buon numero di portaerei ancora disponibili ma senza più piloti esperti.

Uno dei più famosi assi giapponesi degli Zero, Saburō Sakai, nel libro di memorie "Samurai. Caccia zero" descrive il ritorno in volo da Guadalcanal alla base di Rabaul in gravi condizioni fisiche (accecato da un occhio, colpito dai mitraglieri di una formazione di SBD Dauntless che aveva scambiati per caccia e attaccato da dietro). In quel caso lo Zero dimostrò di essere tutt'altro che fragile nell'incassare colpi, ma molti altri piloti giapponesi non erano stati altrettanto fortunati.

Il Mitsubishi A6M era eccellente ma l'Hellcat era superiore. Avrebbe potuto combattere, essendo migliore dell'originario A6M2 e anche dell'A6M3, con una buona superiorità complessiva sul Grumman F4F Wildcat, ma l'Hellcat aveva una superiorità considerevole su entrambi in velocità, potenza di fuoco e corazzatura. Lo Zero, anche nel modello A6M5, mancava pressoché totalmente di armature protettive e solo a seguito di ulteriori miglioramenti si impiegò quest'accortezza tecnica. Nella battaglia aerea gli Hellcat furono aiutati, oltre che dalla superiorità tecnica ed addestrativa, da un sistema che oggi si definisce C3 (comando, controllo, comunicazioni), basato sui radar delle navi statunitensi ed un efficace collegamento radio tra aerei e controllori navali.

Già più difficile per gli americani fu contrattaccare le portaerei giapponesi, rimaste quasi senza aerei. L'attacco ne distrusse una e ne danneggiò altre ma, oltre alla ventina di apparecchi persi in questa missione, altri 80 circa caddero al rientro quando, a corto di carburante, si ritrovarono a volare al buio. L'ammiraglio Chester Nimitz fece accendere le luci sui ponti, aiutando molti aviatori a ritrovare le navi; la decisione non fu un granché pericolosa perché gli aerei giapponesi basati a terra erano ormai fuori causa, ma dimostrò la supremazia raggiunta in quello scontro, perché l'organizzazione e la tecnologia americane ridussero il peso della casualità negli eventi, avendo sotto controllo ogni aspetto della battaglia.

Gli Usa acquisirono il controllo di Saipan e da qui poterono colpire con i bombardieri strategici Boeing B-29 Superfortress anche il territorio metropolitano giapponese. A quel punto non ci furono speranze residue per i giapponesi di battere gli Stati Uniti; questo significava che non esistevano modi di poter riprendere l'iniziativa nel Pacifico.

Gli Hellcat combatterono come caccia e cacciabombardieri durante lo sbarco statunitense nelle Filippine. Furono poi usati l'anno successivo per attaccare Iwo Jima, Okinawa (durante la quale furono equipaggiati con i razzi Tiny Tim, una delle poche occasioni in cui quest'arma fu usata) e persino la baia di Tokyo.

Contrastare i caccia giapponesi, come anche i bombardieri, non sarebbe stato però il problema principale, perché i kamikaze divennero, specie a Okinawa, una minaccia continua. Per affrontarli gli Hellcat erano un po' troppo lenti e gli F4U Corsair ormai operativi cominciarono sempre più a sostituirli.

Durante la guerra il Grumman Hellcat ottenne oltre 6.000 vittorie in circa 2 anni, contro le 2.130 accreditate ai Corsair, e le 905 dei Wildcat a tutto il 1943.

Gli Hellcat combatterono anche nella Royal Navy con 254 esemplari della serie F-3 e 985 della F-5.

Dopo la guerra

Nel dopoguerra gli Hellcat, robusti e agili, erano ormai obsoleti, e questo ne provocò la sostituzione rapida, come accadde ai Republic P-47 Thunderbolt, ai Corsair e al nuovissimo Bearcat. All'orizzonte erano già jet come Grumman Panther e il Republic F-84 Thunderjet.

Durante la guerra di Corea, gli aerei ancora disponibili furono usati come "kamikaze" senza pilota radioguidati, equipaggiati con 3 bombe senza impennaggi di coda da 1.000 libbre, una sotto la fusoliera, le altre sotto le ali, contro obiettivi di alto livello come i ponti.

Altri Hellcat furono usati come aerobersagli, dipinti in colore antimimetico standard arancione, utili per lo sviluppo dei cannoni e soprattutto dei missili antiaerei navali.

Versioni:

• F6F-1 ed F6F-2: versioni basiche che differiscono nella motorizzazione
• F6F-3: variante basica da caccia che forniva da supporto a tutta la successiva evoluzione del modello.
• F6F-5: era un miglioramento più orientato all'attacco e alle missioni offensive: nonostante il peso maggiore delle installazioni e della corazzatura, era leggermente più veloce del precedente, grazie all'adozione, già con gli ultimi lotti dell'F-3, del motore con superpotenza ad iniezione di acqua che incrementava del 10% per brevi periodi la potenza erogabile. Corazzatura aumentata, armi per 900 chili, serbatoio aggiuntivo. Talvolta 2 delle armi alari furono sostituite da cannoni calibro 20 mm.

Entrambe le versioni diedero luce anche alla specialità da caccia notturna imbarcata, con un radar contenuto in posizione asimmetrica nel bordo d'entrata di un'ala e uno schermo radar nell'abitacolo. Il velivolo aveva ovviamente maneggevolezza e prestazioni inferiori, anche per via del radome, la cupola protettiva che conteneva il radar, molto voluminoso. A parte questo, la macchina si dimostrò efficace, stabile a sufficienza per consentire la sicurezza di volo nonostante il carico asimmetrico. L'F6F-3N non era comunque maturo, e il successivo F6F-5N era meglio riuscito e con prestazioni migliori.

Operatori:

• Francia - Marine nationale
• Regno Unito - Royal Navy
• Stati Uniti - United States Navy - United States Marine Corps
• Uruguay - Armada Nacional.

ENGLISH

The Grumman F6F Hellcat is an American carrier-based fighter aircraft of World War II. Designed to replace the earlier F4F Wildcat and to counter the Japanese Mitsubishi A6M Zero, it was the United States Navy's dominant fighter in the second half of the Pacific War, outdueling the faster Vought F4U Corsair, which had problems with carrier landings.

Powered by a 2,000 hp (1,500 kW) Pratt & Whitney R-2800 Double Wasp, the same powerplant used for both the Corsair and the United States Army Air Forces (USAAF) Republic P-47 Thunderbolt fighters, the F6F was an entirely new design, but it still resembled the Wildcat in many ways. Some military observers tagged the Hellcat as the "Wildcat's big brother".

The F6F made its combat debut in September 1943, and was best known for its role as a rugged, well-designed carrier fighter, which was able to outperform the A6M Zero and help secure air superiority over the Pacific theater. A total of 12,275 were built in just over two years.

Hellcats were credited with destroying a total of 5,223 enemy aircraft while in service with the U.S. Navy, U.S. Marine Corps, and Royal Navy Fleet Air Arm. This was more than any other Allied naval aircraft. Postwar, the Hellcat was phased out of front-line service, but remained in service as late as 1954 as a night fighter.

Design and development

XF6F

Grumman had been working on a successor to the F4F Wildcat since 1938 and the contract for the prototype XF6F-1 was signed on 30 June 1941. The aircraft was originally designed to use the Wright R-2600 Twin Cyclone two-row, 14-cylinder radial engine of 1,700 hp (1,300 kW) (the same engine used with Grumman's then-new torpedo bomber under development), driving a three-bladed Curtiss Electric propeller. Instead of the Wildcat's narrow-track, hand-cranked main landing gear retracting into the fuselage that it had inherited, little changed in design from the 1931-debuted Grumman FF-1 fighter biplane, the Hellcat had wide-set, hydraulically actuated landing gear struts that rotated through 90° while retracting backwards into the wings, but with full wheel doors fitted to the struts that covered the entire strut and the upper half of the main wheel when retracted, and twisted with the main gear struts through 90º during retraction. The wing was mounted lower on the fuselage and was able to be hydraulically or manually folded, with each panel outboard of the undercarriage bay folding backwards from pivoting on a specially oriented, Grumman-patented "Sto-Wing" diagonal axis pivoting system much like the earlier F4F, with a folded stowage position parallel to the fuselage with the leading edges pointing diagonally down.

Throughout early 1942, Leroy Grumman, along with his chief designers Jake Swirbul and Bill Schwendler, worked closely with the U.S. Navy's Bureau of Aeronautics (BuAer) and experienced F4F pilots, to develop the new fighter in such a way that it could counter the Zero's strengths and help gain air command in the Pacific Theater of Operations. On 22 April 1942, Lieutenant Commander Butch O'Hare toured the Grumman Aircraft company and spoke with Grumman engineers, analyzing the performance of the F4F Wildcat against the Mitsubishi A6M Zero in aerial combat. BuAer's Lt Cdr A. M. Jackson directed Grumman's designers to mount the cockpit higher in the fuselage. In addition, the forward fuselage sloped down slightly to the engine cowling, affording the Hellcat's pilot good visibility.

Change of powerplant

Based on combat accounts of encounters between the F4F Wildcat and A6M Zero, on 26 April 1942, BuAer directed Grumman to install the more-powerful, 18-cylinder Pratt & Whitney R-2800 Double Wasp radial engine – already powering Chance Vought's Corsair design since its own beginnings in 1940 – in the second XF6F-1 prototype. Grumman complied by redesigning and strengthening the F6F airframe to incorporate the 2,000 hp (1,500 kW) R-2800-10, driving a three-bladed Hamilton Standard propeller. With this combination, Grumman estimated the XF6F-3s performance would increase by 25% over that of the XF6F-1. The Cyclone-powered XF6F-1 (02981) first flew on 26 June 1942, followed by the first Double Wasp-equipped aircraft, the XF6F-3 (02982), which first flew on 30 July 1942. The first production F6F-3, powered by an R-2800-10, flew on 3 October 1942, with the type reaching operational readiness with VF-9 on USS Essex in February 1943.

Further development

The F6F series was designed to take damage and get the pilot safely back to base. A bullet-resistant windshield and a total of 212 lb (96 kg) of cockpit armor was fitted, along with armor around the oil tank and oil cooler. A 250 US gal (950 l) self-sealing fuel tank was fitted in the fuselage. Standard armament on the F6F-3 consisted of six .50 in (12.7 mm) M2/AN Browning air-cooled machine guns with 400 rounds per gun. A center-section hardpoint under the fuselage could carry a single 150 US gal (570 l) disposable drop tank, while later aircraft had single bomb racks installed under each wing, inboard of the undercarriage bays; with these and the center-section hard point late model F6F-3s could carry a total bomb load in excess of 2,000 lb (910 kg). Six 5 in (127 mm) high-velocity aircraft rockets (HVARs) could be carried – three under each wing on "zero-length" launchers.

Two night fighter subvariants of the F6F-3 were developed; the 18 F6F-3E's were converted from standard-3s and featured the AN/APS-4 10 GHz frequency radar in a pod mounted on a rack beneath the right wing, with a small radar scope fitted in the middle of the main instrument panel and radar operating controls installed on the port side of the cockpit. The later F6F-3N, first flown in July 1943, was fitted with the AN/APS-6 radar in the fuselage, with the antenna dish in a bulbous fairing mounted on the leading-edge of the outer right wing as a development of the AN/APS-4; about 200 F6F-3Ns were built. Hellcat night fighters claimed their first victories in November 1943. A total of 4,402 F6F-3s was built through until April 1944, when production was changed to the F6F-5.

The F6F-5 featured several improvements, including a more powerful R-2800-10W engine employing a water-injection system and housed in a slightly more streamlined engine cowling, spring-loaded control tabs on the ailerons, and an improved, clear-view windscreen, with a flat armored-glass front panel replacing the F6F-3's curved plexiglass panel and internal armor glass screen. In addition, the rear fuselage and tail units were strengthened, and apart from some early production aircraft, the majority of the F6F-5's built were painted in an overall gloss sea-blue finish. After the first few F6F-5s were built, the small windows behind the main canopy were deleted. The F6F-5N night-fighter variant was fitted with an AN/APS-6 radar in a fairing on the outer-starboard wing. A few standard F6F-5s were also fitted with camera equipment for reconnaissance duties as the F6F-5P. While all F6F-5s were capable of carrying an armament mix of one 20-mm (.79-in) M2 cannon in each of the inboard gun bays (220 rounds per gun), along with two pairs of .50-in (12.7-mm) machine guns (each with 400 rounds per gun), this configuration was only used on later F6F-5N night fighters. The F6F-5 was the most common F6F variant, with 7,870 being built.

Other prototypes in the F6F series included the XF6F-4 (02981, a conversion of the XF6F-1 powered by an R-2800-27 and armed with four 20-mm M2 cannon) which first flew on 3 October 1942 as the prototype for the projected F6F-4. This version never entered production and 02981 was converted to an F6F-3 production aircraft. Another experimental prototype was the XF6F-2 (66244), an F6F-3 converted to use a Wright R-2600-15, fitted with a Birman-manufactured mixed-flow turbocharger, which was later replaced by a Pratt & Whitney R-2800-21, also fitted with a Birman turbocharger. The turbochargers proved to be unreliable on both engines, while performance improvements were marginal. As with the XF6F-4, 66244 was soon converted back to a standard F6F-3. Two XF6F-6s (70188 and 70913) were converted from F6F-5s and used the 18-cylinder 2,100 hp (1,566 kW) Pratt and Whitney R-2800-18W two-stage supercharged radial engine with water injection and driving a Hamilton-Standard four-bladed propeller. The XF6F-6s were the fastest version of the Hellcat series with a top speed of 417 mph (671 km/h), but the war ended before this variant could be mass-produced.

The last Hellcat rolled out in November 1945, the total production being 12,275, of which 11,000 had been built in just two years. This high production rate was credited to the sound original design, which required little modification once production was under way.

Operational history

U.S. Navy and Marines

The U.S. Navy much preferred the more docile flight qualities of the F6F compared with the Vought F4U Corsair, despite the superior speed of the Corsair. This preference was especially noted during carrier landings, a critical success requirement for the Navy, in which the Corsair was fundamentally flawed in comparison. The Corsair was thus released by the Navy to the Marine Corps, which without the need to worry about carrier landings, used the Corsair to immense effect in land-based sorties. The Hellcat remained the standard USN carrier-borne fighter until the F4U series was finally cleared for U.S. carrier operations in late 1944 (the carrier landing issues had by now been tackled largely due to use of Corsair by the Royal Navy Fleet Air Arm). In addition to its good flight qualities, the Hellcat was easy to maintain and had an airframe tough enough to withstand the rigors of routine carrier operations. Like the Wildcat, the Hellcat was designed for ease of manufacture and ability to withstand significant damage.

The Hellcat first saw action against the Japanese on 1 September 1943, when fighters off USS Independence shot down a Kawanishi H8K "Emily" flying boat. Soon after, on 23 and 24 November, Hellcats engaged Japanese aircraft over Tarawa, shooting down a claimed 30 Mitsubishi Zeros for the loss of one F6F. Over Rabaul, New Britain, on 11 November 1943, Hellcats and F4U Corsairs were engaged in day-long fights with many Japanese aircraft including A6M Zeros, claiming nearly 50 aircraft.

When trials were flown against a captured A6M5 model Zero, they showed that the Hellcat was faster at all altitudes. The F6F out-climbed the Zero marginally above 14,000 ft (4,300 m) and rolled faster at speeds above 235 mph (378 km/h). The Japanese fighter could out-turn its American opponent with ease at low speed and enjoyed a slightly better rate of climb below 14,000 ft (4,300 m). The trials report concluded:

Do not dogfight with a Zero 52. Do not try to follow a loop or half-roll with a pull-through. When attacking, use your superior power and high speed performance to engage at the most favorable moment. To evade a Zero 52 on your tail, roll and dive away into a high speed turn.

Hellcats were the major U.S. Navy fighter type involved in the Battle of the Philippine Sea, where so many Japanese aircraft were shot down that Navy aircrews nicknamed the battle the "Great Marianas Turkey Shoot". The F6F accounted for 75% of all aerial victories recorded by the U.S. Navy in the Pacific. Radar-equipped Hellcat night fighter squadrons appeared in early 1944.

A formidable opponent for the Hellcat was the Kawanishi N1K, but it was produced too late and in insufficient numbers to affect the outcome of the war.

Sortie, kill, and loss figures

U.S. Navy and Marine F6F pilots flew 66,530 combat sorties and claimed 5,163 kills (56% of all U.S. Navy/Marine air victories of the war) at a recorded cost of 270 Hellcats in aerial combat (an overall kill-to-loss ratio of 19:1 based on claimed kills). Claimed victories were often highly exaggerated during the war. Even so, the aircraft performed well against the best Japanese opponents with a claimed 13:1 kill ratio against the A6M Zero, 9.5:1 against the Nakajima Ki-84, and 3.7:1 against the Mitsubishi J2M during the last year of the war. The F6F became the prime ace-maker aircraft in the American inventory, with 305 Hellcat aces. The U.S. successes were not just attributed to superior aircraft – from 1942 onwards, they faced increasingly inexperienced Japanese aviators and had the advantage of increasing numerical superiority. In the ground-attack role, Hellcats dropped 6,503 tons (5,899 tonnes) of bombs.

The U.S. Navy's all-time leading ace, Captain David McCampbell, scored all his 34 victories in the Hellcat. He once described the F6F as "... an outstanding fighter plane. It performed well, was easy to fly, and was a stable gun platform, but what I really remember most was that it was rugged and easy to maintain."

During the course of World War II, 2,462 F6F Hellcats were lost to all causes – 270 in aerial combat, 553 to antiaircraft ground and shipboard fire, and 341 due to operational causes. Of the total figure, 1,298 were destroyed in training and ferry operations, normally outside of the combat zones.

British use

The British Fleet Air Arm (FAA) received 1,263 F6Fs under the Lend-Lease Act; initially it was known as the Grumman Gannet Mark I. The name Hellcat replaced it in early 1943 for the sake of simplicity, the Royal Navy at that time adopting the use of the existing American naval names for all the U.S.-made aircraft supplied to it, with the F6F-3 being designated Hellcat F Mk.I, the F6F-5, the Hellcat F Mk.II and the F6F-5N, the Hellcat NF Mk.II.They saw action off Norway, in the Mediterranean, and in the Far East. Several were fitted with photographic reconnaissance equipment similar to the F6F-5P, receiving the designation Hellcat FR Mk.II. The Pacific War being primarily a naval war, the FAA Hellcats primarily faced land-based aircraft in the European and Mediterranean theaters, and as a consequence experienced far fewer opportunities for air-to-air combat than their USN/Marines counterparts, nevertheless, they claimed a total of 52 enemy aircraft kills during 18 aerial combats from May 1944 to July 1945. 1844 Naval Air Squadron, on board HMS Indomitable of the British Pacific Fleet was the highest scoring unit, with 32.5 kills.

FAA Hellcats, as with other Lend-Lease aircraft, were rapidly replaced by British aircraft after the end of the war, with only two of the 12 squadrons equipped with the Hellcat at VJ-Day still retaining Hellcats by the end of 1945.These two squadrons were disbanded in 1946.

Postwar use

After the war, the Hellcat was succeeded by the F8F Bearcat, which was smaller, more powerful (powered by uprated Double Wasp radials) and more maneuverable, but entered service too late to see combat in World War II.

The Hellcat was used for second-line USN duties, including training, Naval Reserve squadrons, and a handful were converted to target drones. In late 1952, Guided Missile Unit 90 used F6F-5K drones, each carrying a 2,000 lb (910 kg) bomb, to attack bridges in Korea; flying from USS Boxer, radio controlled from an escorting AD Skyraider.

The French Aéronavale was equipped with F6F-5 Hellcats and used them in Indochina. These were painted in Gloss Sea Blue, similar to post-World War II US Navy aircraft until about 1955, but have a modified French roundel with an image of an anchor.

The Uruguayan Navy also used them until the early 1960s.

The F6F-5 subtype also gained fame as the first aircraft used by the U.S. Navy's Blue Angels official flight demonstration team at its formation in 1946.

Variants:

• XF6F prototypes
• XF6F-1 First prototype, powered by a two-stage 1,600 hp (1,193 kW) Wright R-2600-10 Cyclone 14 radial piston engine.
• XF6F-2 The first XF6F-1 prototype revised and fitted with a turbocharged Wright R-2600-16 Cyclone radial piston engine. R-2600 replaced by turbocharged R-2800-21.
• XF6F-3 Second prototype fitted with a two-stage supercharged 2,000 hp (1,491 kW) Pratt & Whitney R-2800-10 Double Wasp radial piston engine.
• XF6F-4 One F6F-3 fitted with a two-speed turbocharged 2,100 hp (1,566 kW) Pratt & Whitney R-2800-27 Double Wasp radial piston engine.
• XF6F-6 Two F6F-5s that were fitted with the 2,100 hp (1,566 kW) Pratt & Whitney R-2800-18W radial piston engine, and four-bladed propellers.

Series production:

• F6F-3 (British designation Gannet F. Mk. I, and then later, renamed Hellcat F. Mk. I, January 1944) - Single-seat fighter, fighter-bomber aircraft, powered by a 2,000 hp (1,491 kW) Pratt & Whitney R-2800-10 Double Wasp radial piston engine.
• F6F-3E Night fighter version, equipped with an AN/APS-4 radar in a fairing on the starboard outer wing.
• F6F-3N Another night fighter version, equipped with a newer AN/APS-6 radar in a fairing on the starboard outer wing.
• F6F-5 Hellcat (British Hellcat F. Mk. II) Improved version, with a redesigned engine cowling, a new windscreen structure with an integral bulletproof windscreen, new ailerons and strengthened tail surfaces; powered by a 2,200 hp (1,641 kW) Pratt & Whitney R-2800-10W (-W denotes Water Injection) radial piston engine.
• F6F-5K Hellcat A number of F6F-5s and F6F-5Ns were converted into radio-controlled target drones.
• F6F-5N Hellcat (British Hellcat N.F. Mk II) Night fighter version, fitted with an AN/APS-6 radar. Some were armed with two 20 mm (0.79 in) AN/M2 cannon in the inner wing bays and four 0.50 in (12.7 mm) M2 Browning machine guns in the outer.
• F6F-5P Hellcat Small numbers of F6F-5s were converted into photo-reconnaissance aircraft, with the camera equipment being fitted in the rear fuselage.
• Hellcat FR. Mk. II This designation was given to British Hellcats fitted with camera equipment.
• FV-1 Proposed designation for Hellcats to be built by Canadian Vickers; cancelled before any built.

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