The T-45 Goshawk is the most modern advanced jet trainer aircraft in service with the US Navy, jointly built by McDonnell Douglas (which was acquired by Boeing in 1997) and British Aerospace (renamed BAE Systems in 1999) as a derivative of the UK's British Aerospace (Hawker Siddeley) Hawk land-based jet trainer. However, I should emphasize that the T-45 Goshawk did not exist in its own right despite the fact that it owes its heritage to the Hawk jet trainer. During my first visit to the Western Museum of Flight at its current location in Torrance, I happened to notice a wind tunnel of an aircraft on a display stand across from an F-86 Sabre jet fighter, and when I saw a label on the stand identifying the wind tunnel as being of an early 1980s Northrop jet trainer design for the US Navy, I realized than more than one company undertook design studies for a carrier-based advanced jet trainer to replace the Navy's fleet of T-2 Buckeyes. Given that I have in my personal possession a copy of Tony Chong's book Flying Wings & Radical Things: Northrop's Secret Aerospace Projects & Concepts 1939-1994 and thanks to the Secret Projects Forum, it is now possible for me to discuss advanced jet trainer designs from southern California's aircraft industry that competed with T-45 Goshawk.
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Top left: Lockheed derivative of the Alpha Jet for the VTX-TS competition
Top right: Artist's impression of the Rockwell International T-2X project
Bottom: Company artwork of the proposed Rockwell International NA-424
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In 1978, the US Navy launched VTX-TS requirement for an advanced jet trainer to replace the North American T-2 Buckeye and Douglas TA-4 Skyhawk. In addition to the joint McDonnell Douglas/British Aerospace team, Rockwell International submitted bids for the VTX-TS competition, as did a joint team between Northrop and Vought as well as Lockheed. The Lockheed submission was a navalized derivative of the Dassault/Dornier Alpha Jet jet trainer and light attack aircraft, and it featured nose landing gear modified for nose-tow catapults, a slightly longer nose, reinforced legs of the landing gear, and a stronger arrestor hook. The Lockheed trainer derivative of the Alpha Jet was to be powered by a pair of Teledyne CAE 490 turbofans (a proposed version of the SNECMA Turbomeca Larzac turbofan to be built under license by Teledyne Turbine Engines) on the sides of the fuselage below the wings. In September 1980, a French Air Force Alpha Jet serialled A58) was flown to the US and made a total of 88 demonstration flights at US Navy air bases in Florida, Maryland, Mississippi, and Texas, and 67 Navy pilots carried out those flights. Two Rockwell International designs for the VTX-TS requirement were proposed in 1980, the NA-424 and T-2X. The T-2X was an evolutionary derivative of the T-2 Buckeye which retained the straight wings of the T-2 but differed in having two turbofans with square-shaped air intakes situated in the wing roots, while the NA-424 was to have a new airframe featuring backswept wings, a slightly pointed nose, a dorsal fin protruding from the base of the vertical stabilizer and reaching an area behind the cockpit canopy, and two turbofans on the sides of the fuselage above the wing roots. Two variations of the NA-424 were studied by Rockwell International, one with a low-mounted horizontal stabilizer (in contrast to the T-2 Buckeye's mid-mounted horizontal stabilizer that gave the tail empennage of the Buckeye a cruciform appearance in front view) and another having a T-tail configuration.
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Top: A wind tunnel model of the N-351 design at the Western Museum of Flight, photographed by me in June 2016
Bottom left: A three-view drawing of the N-350 from Northrop project documents
Bottom right: An artist's rendering of the N-351 jet trainer preparing for a landing on an aircraft carrier |
Now all of this brings my attention to Northrop's bidding for the VTX-TS competition. When the US Navy in 1975 began discussions with aircraft manufacturers about possible replacements for the T-2 Buckeye and TA-4J, Northrop envisaged the N-328 subsonic advanced jet trainer with tandem seating, straight wings, and two turbofan engines (possibly Garrett TFE731s) on the sides of the fuselage and mounted above the wing roots. The N-328 would have been the Navy equivalent of Northrop's N-325 advanced jet trainer proposal for the US Air Force designed in 1974, and Northrop also conceived the N-329 for use by both the Air Force and Navy. The N-328 and N-329 remained design studies only, but in late 1977 Northrop undertook design work on the N-334 project, which was powered by two TFE731 turbofans on the sides of the fuselage above the wing roots and drew its design heritage from the CASA C-101 and AIDC AT-3 jet trainers (single-engine and twin-podded engine configurations were also studied by Northrop for the N-334). The N-334 was submitted to the Navy Air Development Center in early 1978, and following further study under contract from the NADC, Northrop in 1980 submitted the final N-334 design for the VTX-TS requirement. After being selected along with five other companies by the Naval Air Systems Command (NAVAIR) on August 19, 1980, for the next phase of the VTX-TS competition, it teamed up with Chance Vought (which had worked on the V-532B advanced jet trainer project for the US Navy in the late 1970s) to conceive the N-350 advanced jet trainer, for which initial drawings had been devised a few months earlier. The N-350 was 38 feet 8.4 in (11.8 meters) long with a wingspan of 32 feet 4.8 in (9.88 meters), and power was provided by either two 3,500 lb (15.57 kN) thrust Garrett TFE731 turbofans or two 3,300 lb (14.68 kN) thrust Pratt & Whitney JT15D turbofans. By December 1980, the Northrop/Vought team envisaged its final design for the VTX-TS contest under the company designation N-351, which differed from the N-350 in having wings with greater leading edge sweep and a more pointed nose, and which measured 40 feet (12.2 meters) long with a wingspan of 29 feet 7.3 in (9.02 meters).
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| The McDonnell Douglas/British Aerospace T-45 Goshawk, which was selected over the NA-424 and N-351 as the winning design for the VTX-TS competition. |
On November 19, 1981, the US Navy announced that the proposal by the McDonnell Douglas/British Aerospace for a derivative of the British Aerospace Hawk had been declared the winner of the VTX-TS competition. The winning McDonnell Douglas/British Aerospace design became the T-45 Goshawk and made its first flight on April 16, 1988.
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