The Navy’s bat-winged bomber-killer

What makes it special

Full specifications

Figures are for the production F4D-1 (redesignated F-6A in 1962). Sources differ slightly on a few values — these are the most commonly cited; contested figures are flagged.

Baseline note: the figures below describe the F4D-1 as the fleet actually flew it — the sole production mark, redesignated F-6A in September 1962, powered by a single Pratt & Whitney J57-P-8, -8A or -8B. They are drawn from Enzo Angelucci’s The American Fighter, Joe Baugher’s serial-by-serial account of the type, René Francillon’s McDonnell Douglas Aircraft since 1920 and Tommy Thomason’s U.S. Naval Air Superiority, cross-checked against the National Naval Aviation Museum’s own data for its airframe. Deltas for the two XF4D-1 prototypes with the Westinghouse J40 and for the F5D-1 Skylancer development are in grey. Six cautions before the numbers, because the published tables for this aeroplane repeat several errors that are worth naming. First, how many were built. Baugher gives 419 production F4D-1s, the last delivered on 22 December 1958, which with the two XF4D-1 prototypes makes 421 airframes; the English Wikipedia article contradicts itself, saying 419 in its text, 420 in its variants list and 422 in its infobox. The 419 and 421 used here are the figures that can be tied to deliveries. Second, the speed record was not flown by Bill Bridgeman. It was flown by Lieutenant Commander James B. Verdin, US Navy, on 3 October 1953 over the Salton Sea in the second XF4D-1, BuNo 124587; Bridgeman was the Douglas man on the D-558-2 Skyrocket, a different aeroplane and a different programme. Douglas’s own Bob Rahn took the 100 km closed-circuit record at 728.11 mph a fortnight later, on 16 October 1953. Third, the record speed in metric. 752.944 mph converts to 1,211.746 km/h, which is what the FAI rounds to 1,211.75; the 1,211.487 km/h that circulates through the English Wikipedia is an arithmetic slip and should not be repeated. Fourth, the supersonic claim. The Skyray is very widely called the first naval fighter to exceed Mach 1 in level flight, but Thomason points out that the Navy’s own F4D-1 acceptance report states the aircraft "does not have level flight supersonic capability", that neither Ed Heinemann nor Rahn claimed it in their memoirs, and that the record run was made in an ambient temperature of 37 °C, which lifted the local speed of sound from about 761 to about 790 mph and makes Verdin’s 752.944 mph roughly Mach 0.95. On Navy records the first is a Grumman F11F Tiger prototype. Fifth, the weights. Baugher separates 16,024 lb empty, 22,648 lb combat, 25,000 lb gross and 27,116 lb maximum; the commonly copied table labels the 22,648 lb combat figure as "gross", which flatters the wing loading of a fuelled and armed aeroplane by about eight pounds per square foot. Both are given below. Sixth, the radar. Compilations that list an AN/APQ-72 for the Skyray are wrong: that is the large McDonnell F4H-1 Phantom II set and it will not fit this radome. The F4D-1 carried the Westinghouse Aero 13F fire-control system built around the AN/APQ-50A.

Armament & payload

The Skyray was designed around unguided rockets and retired carrying missiles, which is the whole of 1950s naval air defence compressed into one airframe

Douglas drew the D-571-1 as a rocket carrier, because in 1947 a salvo of spin-stabilised rockets was the only credible way for a fighter to destroy a bomber quickly. By the time the F4D-1 reached a squadron in April 1956 the Sidewinder had arrived, and the fleet promptly reorganised the aeroplane around it: four 20 mm Mk 12 cannon with sixty-five rounds apiece — about five seconds of fire — were routinely pulled out to buy back weight and drag, and the pylons filled with missiles instead of pods. The Aero 13F fire-control system was the limiting component in every case. It could steer the pilot into a rocket or missile solution from astern and it could not manage a head-on attack, which is precisely what an interceptor chasing a high, fast bomber most needs; a 1957 Navy evaluation judged the F4D-1 only marginally effective as an all-weather fighter, citing its modest top speed, its poor transonic handling and exactly that armament-control limitation. Fits varied far more by squadron practice and production block than any published table suggests: cannon fitment, pod type and the presence of drop tanks all changed across 419 aircraft and across Navy, Marine and reserve units, and no single configuration should be treated as standard.

Store fits here are compiled from Joe Baugher’s F4D-1 entry, the National Naval Aviation Museum and the type’s published hardpoint capacity, not from a released Navy weapons-loading manual — none is in open circulation for this aircraft. Rounds per gun and maximum external load are consistent across sources; which pylons were plumbed and wired on any given block is not, and the loadouts above are representative rather than authoritative.

Variants

Douglas built the Skyray in exactly one production mark and spent the rest of the programme on aircraft that were cancelled

The variant list looks thin because it is. There was one production model, the F4D-1, redesignated F-6A in 1962; everything else on this list is a study, a project, a cancelled order or a four-aircraft research fleet. That is not a sign of a simple programme but of a difficult one, in which almost all the engineering effort went into two things: replacing an engine that never worked, and then designing a successor the Navy declined to buy.

The engine is the whole story of the delay. The Skyray was designed around the Westinghouse J40, an engine that was cancelled without a single production unit delivered and which also crippled the Vought F7U Cutlass and the McDonnell F3H Demon. The prototype flew on a borrowed Allison J35 of 5,000 lbf, then on a J40 without afterburner, then on an afterburning XJ40 of 11,600 lbf that was good enough to take the world speed record and not good enough to build a fleet fighter around. The replacement, the Pratt & Whitney J57, was far better and considerably larger, and fitting it meant a redesigned fuselage. Between the mock-up review of March 1949 and fleet introduction in April 1956 lie seven years, and in the middle of them the North American F-100 and the MiG-19 both entered service.

What the Navy got at the end of it was a genuinely extraordinary climbing machine and a genuinely awkward aeroplane. Baugher records the Skyray’s reputation plainly as a difficult aircraft to fly with poor transonic flying qualities, and the specifics bear that out: the main undercarriage legs did not extend together, so the aircraft would skid on gear extension and again on retraction, and the approach demanded a nose-high delta attitude behind a fire-control scope so badly placed that a squadron mechanic’s home-made periscope, assembled from his wife’s mirrors, was adopted as a Navy fix. Set against that, the roll rate was so high that Air Force chase pilots struggled to find anything that could stay with it in a turn. It was fast to height, sharp in the hands of a good pilot and unforgiving in the hands of an average one, and the fleet never had eight years of experience with it before it was gone.

D-571-1 (1947–1948, design study)

Twin Westinghouse J34s with afterburners, a thick delta with no conventional fuselage beyond a cockpit pod, four cannon projecting ahead of the leading edge and rockets as the primary weapon. Alexander Lippisch’s wartime delta research reached this drawing board through several members of the Douglas team; the Navy funded it to mock-up stage in June 1947.

XF4D-1 (1951–1956, 2 built)

First flight 23 January 1951 at Muroc by Bob Rahn, on a borrowed 5,000 lbf Allison J35-A-17 because the intended Westinghouse J40 did not exist yet. Later re-engined with a non-afterburning XJ40-WE-6, then an 11,600 lbf afterburning XJ40-WE-8. BuNo 124587 took the world absolute speed record on 3 October 1953 and carrier-qualified aboard USS Coral Sea the same month. Redesignated YF-6A in 1962.

F4D-1 (1956–1958, 419 built)

The only production mark and the aeroplane this page describes. The switch to the much larger Pratt & Whitney J57 forced a new fuselage, cost roughly four years and let the F-100 Super Sabre and the MiG-19 into service first. Production aircraft added reprofiled intakes with baffle plates, a reworked aft fuselage to kill buffet, and the Aero 13F. The last was delivered on 22 December 1958.

F-6A (from September 1962, redesignation)

The same aeroplane under the tri-service system. It is not the F-4D, which is the "D" model of the McDonnell Douglas Phantom II — a confusion the type has never entirely escaped.

F4D-2 (1953, 100 ordered, cancelled)

A re-engined F4D-1 with the J57-F-14. The order was cancelled before any airframe was laid down and no F4D-2 was ever built.

F4D-2N (1953–1955, project only)

An all-weather F4D-2 with a lengthened nose housing twin radar scanners. Engineering work took it so far from the F4D-1 that the Navy gave it a new type number rather than a suffix.

F5D-1 Skylancer (1956–1958, 4 built)

The F4D-2N grown up: thinner wing, longer area-ruled fuselage, 1,333 US gal of internal fuel and Mach 1.48. First flight 21 April 1956 from Edwards, supersonic on the sortie. Nine test aircraft and 51 production machines were ordered; all but four were cancelled, officially for overlap with the F8U Crusader and in practice to stop Douglas taking any more of the Navy’s fighter business. It removed Douglas from fighter design for good. Sources disagree on the first-flight pilot: Baugher and the Douglas accounts credit Bob Rahn, the English Wikipedia credits Lieutenant Commander Alan Shepard, who certainly flew the type during Navy evaluation.

NACA and NASA F4D-1s (early 1960s–1969, 4 aircraft)

Four Skyrays passed to NACA and then NASA for aerodynamic research after the fleet finished with them. The last Navy Skyray flight of all was a delivery flight to the National Naval Aviation Museum at Pensacola on 25 November 1969, five years after the last squadron gave the type up.

Ten airframes survive from the Skyray family and not one of them flies; every survivor is an original aircraft and there are no reproductions. The record-setter itself is among them: XF4D-1 BuNo 124587, the machine Verdin flew over the Salton Sea, stands at the main gate of Naval Air Weapons Station China Lake on loan from the National Naval Aviation Museum. Its sister prototype, 124586, was burned up in fire-fighting practice in the 1980s. Seven F4D-1s remain — 134748 at the Pima Air and Space Museum, Tucson; 134764 at NAS Patuxent River; 134806 at the National Naval Aviation Museum, Pensacola; 134836 at the Intrepid Sea, Air and Space Museum in New York, moved there from the New England Air Museum in 2021; 134936 at the Pueblo Weisbrod Aircraft Museum in Colorado; 134950 at Aviation Heritage Park, NAS Oceana; and 139177, long shown by the Flying Leatherneck Aviation Museum at MCAS Miramar, whose collection has been in relocation since that site closed, so a visitor should confirm where it currently stands before travelling. Both surviving Skylancers earned their second lives with NASA rather than the Navy, and both outlived their parent programme by a decade. BuNo 139208, as NASA 212 and then NASA 708, was fitted with an ogival wing planform of the family later adopted for Concorde and flew it for the American supersonic transport programme, data from which was shared with European designers; it also served as a pilot-visibility testbed for the X-20 Dyna-Soar before retiring in 1968, and is now at the Evergreen Aviation and Space Museum in McMinnville, Oregon. BuNo 142350, as NASA 213 and then NASA 802, flew Dyna-Soar abort profiles at Edwards precisely because its shape and its handling were close enough to the spaceplane’s to be instructive, and among the pilots who flew those approaches was Neil Armstrong; after Dyna-Soar was cancelled in December 1963 the aircraft finished as a chase plane and retired in 1970. Restored in 2017–2018, it is displayed at the Armstrong Air and Space Museum in Wapakoneta, Ohio, the town where Armstrong was born — which makes the Skyray’s only real descendant a museum piece in a town famous for something else entirely. The remaining two Skylancers were grounded in 1961 and stripped for spares.

From German deltas to the boneyard

Twelve Skyray stories

The Skyray in pictures

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The Skyray in motion

A curated video feature for the Douglas F4D Skyray is coming soon. In the meantime, explore the photo gallery above and the operator map below.

Where the Skyray flew

Where the record stands

The Skyray has no confirmed air-to-air combat record. It was built to intercept high-altitude bombers, and it stood alert through some of the tensest years of the Cold War — including VFAW-3’s deployment to Key West during the 1962 Cuban Missile Crisis — but the bombers it was meant to kill never came. Its legacy is written in world records and rapid climbs, not in kills.

Compare the combat record of every military aircraft. Figures as of July 2026.

Everything people ask about the F4D Skyray

Continue the tour

Every fact, checked

• National Naval Aviation Museum — F4D-1 SkyrayOfficial Navy museum page: designer, dates, records, VFAW-3/NORAD and the nickname.
• This Day in Aviation — 3 October 1953Sourced account of Verdin’s speed record with exact speeds, FAI file and aircraft.
• This Day in Aviation — F4D climb recordsFAI file numbers and times for Major LeFaivre’s 1958 time-to-climb records.
• Smithsonian Air & Space — “Beautiful Climber”Feature on the Lippisch influence, handling reputation, pilots and the Collier Trophy.
• Smithsonian NASM — Westinghouse J40-WE-8Authoritative on the J40 powering the record flight and the J57 production switch.
• Joe Baugher — Douglas F4D-1 (F-6A) SkyrayDetailed reference for specifications, weights, engine variants and service dates.
• Pima Air & Space Museum — Douglas F4D-1Museum specification sheet and production and service summary.
• Vintage Aviation News — F5D-1 SkylancerThe Skylancer derivative, its cancellation and the NASA / Armstrong / Dyna-Soar connection.