A-3 Skywarrior

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Image:A3D Skywarrior.jpg The A-3 Skywarrior was the only strategic bomber ever built for the United States Navy. For many years after its introduction, it was also the heaviest aircraft ever flown from an aircraft carrier.

1 Development
2 Description
3 Variants
4 Units using the A-3
- 4.1 USN squadrons
5 Specifications (A3D-2/A-3B Skywarrior)
6 References
7 Related content

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Development

Early in the Second World War, the Navy began to explore the concept of a jet-powered aircraft operating from aircraft carriers. Success encouraged further development of the concept, and early in the post war years the Navy began to consider jet power as a possible means of operating from carriers, aircraft that were large enough to provide a strategic bombing capability.

In January 1948, the Chief of Naval Operations issued a requirement to develop a long-range, carrier-based attack plane that could deliver a 10,000-pound (4,500 kg) bomb load. The contract which the Navy awarded to the Douglas Aircraft Company on 29 September 1949 led to the development and production of the A3D Skywarrior. It was designed by Ed Heinemann, also to win fame for the A-4 Skyhawk. The prototype XA3D-1 first flew on 28 October 1952.

Considerable development problems, largely with the original engines, delayed the introduction of the Skywarrior until spring 1956. Because of its cumbersome size, it was nicknamed "the Whale" (after it converted to the electronic warfare role, it became "the Electric Whale"). Production ended in 1961.

The Skywarrior's strategic bombing role faded quickly after 1960, briefly replaced by the A3J Vigilante before the Navy abandoned the concept of carrier-based strategic nuclear weaponry. Skywarriors saw some use in the conventional bombing and mine-laying role during the Vietnam War from 1965 through 1967, but most of its subsequent service was in the tanker, photographic reconnaissance, and electronic warfare roles. The 282 Skywarriors the Navy purchased served well in many roles for more than two decades, the last USN Skywarriors retiring on 27 September 1991. RDT&E units, notably Point Mugu and China Lake, attempted to retain their A-3 testbeds, VADM Dunleavy, an old A-3 Navigator, regretfully made the decision final.

In the agreement Hughes had with the Navy, the Navy had agreed to retain at least one aircraft in inviolate storage at Davis-Monthan for long term parts support for major structural parts. Westinghouse also operated an A-3 in a similar arrangement.

The NAVAIR Weapons System Manager, who participated in the drafting of the contract, saw that support as no longer possible, and Hughes was contacted to meet with Westinghouse and Raytheon to finalize plans for the support shutdown of the aircraft. At the last Integrated Logistics meeting at Alameda, both Raytheon and Hughes indicated their willingness to obtain fleet assets vice sending them to Davis-Monthan, thereby saving the airframes from destruction and saving the Navy the cost of storage at AMARC.

As the plan matured, two other contractors, Thunderbird Aviation and CTAS also elected to participate in similar agreements.

The fleet spares from ASO were distributed between the contractors evenly, and warehouses were emptied all over the United States. Unfortunately, due to misunderstandings and reorganizations within the Navy, the world wide ASO assets were scrapped, not getting to the contractors.

In early 1993, CTAS decided that they no longer had use for their aircraft, and Hughes had several programs needing additional assets.

In early 1994, a USAF program decided to modify an A-3 for F-15 Radar tests, and the only available airframe was stored at Alameda since the fleet shutdown. Hughes added that aircraft to the bailment, and ferried the aircraft to Van Nuys for modifications. An entire nose section was removed from a stricken F-15B at Davis-Monthan, and grafted onto the front of the aircraft. Racks and equipment were installed in the cabin, and the aircraft is utilized by Hughes and the USAF for F-15 software development.

In 1994 Westinghouse decided to terminate their agreement with the Navy, and Thunderbird added their aircraft to the Thunderbird bailment.

In 1996, Thunderbird Aviation went into receivership, and Hughes, through mutual cost savings to the Government, added the Thunderbird assets to the contract, prepping them for ferry at Deer Valley airport, and relocating them to Mojave, CA and Tucson, AZ for long term storage.

In December, 1996, Raytheon bought the aerospace units of Hughes Aircraft Company. Hughes Aeronautical Operations, now a part of Raytheon Systems, continues to operate the A3's from their base at Van Nuys Airport, CA.

The US Air Force ordered 294 of the derivative B-66 Destroyer, most of which were used in the reconnaissance and electronic warfare roles.

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Description

The Skywarrior had a 36° degree swept wing and two Pratt & Whitney J57 turbojet engines. Although prototypes had used the intended Westinghouse J40, that powerplant proved disastrous, and was subsequently cancelled. The turbojets could be supplemented by a provision for twelve 4,500 lbf (20 kN) thrust JATO bottles), allowing take-off from carriers that did not have catapults. The aircraft had a largely conventional semi-monocoque fuselage, with the engines in under-wing nacelles. Flight controls were hydraulic, and both wings and vertical tailfin could fold for carrier stowage. Capacious internal fuel tanks provided long range.

The A3D had a crew of three: pilot, bombardier/navigator (BN), and gunner. Efforts to reduce weight had led to the deletion of ejection seats during the design process, based on the assumption that most flights would be at high altitude. Aircrews began joking morbidly that "A3D" stood for "All Three Dead" (in fact, in 1973 the widow of a Skywarrior crewman killed over Vietnam sued the company for not providing ejection seats).

The Skywarrior could carry up to 12,000 lb (4,445 kg) of weaponry in the fuselage bomb bay, which in later marks was used for sensor and camera equipment or additional fuel tanks. An AN/ASB-1A bomb-director system was initially installed, later replaced by a revised AN/ASB-7 with a slightly reshaped nose. Defensive armament was two 20mm cannon in a radar-operated tail turret.

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Variants

Note: under the original Navy designation scheme, the Skywarrior was designated A3D (i.e., third Attack aircraft from Douglas Aircraft). In September 1962 the new Tri-Services designation system was implemented and the aircraft was redesignated A-3. Where applicable, pre-1962 designations are listed first, post-1962 designations in parentheses.

XA3D-1: Two prototypes with Westinghouse J40 turbojets, no cannon in tail turret.
YA3D-1 (YA-3A): One pre-production prototype with Pratt & Whitney J57 engines. Later used for tests at the Naval Air Missile Test Center.
A3D-1 (A-3A): 49 initial production versions, serving largely in developmental role in carrier service.
A3D-1P (RA-3A): One A3D-1 converted as a prototype for the A3D-2 with camera pack in the weapon bay.
A3D-1Q (EA-3A): Five A3D-1s converted for the electronic reconnaissance (ELINT) role, with ECM equipment and four operators in weapons bay.
A3D-2 (A-3B): Definitive production bomber version, with stronger airframe, more powerful engines, slightly larger wing area (812 ft² versus 779 ft²), provision for in-flight refueling reel for tanker role. Final 21 built had new AN/ASB-7 bombing system, reshaped nose; deleted tail turret in favor of electronic warfare installation.
A3D-2P (RA-3B): 30 photo-reconnaissance aircraft with weapons bay package for up to 12 cameras plus photoflash bombs. Increased pressurization allowed camera operator to enter the bay to check the cameras. Some retained tail guns, but most were later converted to ECM tail of late A-3Bs.
A3D-2C (EA-3B): 24 electronic warfare versions with pressurized compartment in former weapon bay for three ECM operators, various sensors. Some early models had tail guns, but these were replaced with the ECM tail.
A3D-2T (TA-3B): 12 bomber-trainer versions. Five later converted as VIP transports (two resignated UTA-3B).
KA-3B: 85 A-3B bombers refitted in 1967 for the tanker role with probe-and-drogue system in place of bombing equipment.
EKA-3B: 34 KA-3B tankers refitted for dual ECM/tanker role, with electronic warfare equipment and tail fairing in place of rear turret. Most were converted back to KA-3B configuration (with no ECM gear) after 1975.
ERA-3B: Eight RA-3Bs converted as electronic aggressor SEAD aircraft with ECM in new tail cone, ventral fairing, cylindrical fairing atop vertical fin, and wing tips. Added chaff dispensers and two ram-air turbines to power the new equipment. Crew increased to five with addition of two ECM evaluators in a pressurized cabin in the bomb bay.
NRA-3B: Six RA-3Bs converted for various non-combat test purposes.
VA-3B: One EA-3B converted as a VIP transport.