Blood relatives


Harvards still race at Reno every year. The famous prop roar is the sound of those supersonic tips.

When it entered RAF service in July 1939, the US-built North American Harvard satisfied Britain’s desperate need for an advanced trainer that could bridge the widening gulf between the biplanes used for primary training and the new generation of fighters such as the Hurricane, which had already been operational for eighteen months. Yet, landmark though it may have been in Britain’s belated rearmament programme, the Harvard was only one member of a family of closely related aircraft that were produced over a period of 30 years, and which filled a variety of roles around the world, from trainer to fighter-bomber.


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The North American NA-16 in its original form with twin, tandem open cockpits. 

The pater familias of this dynasty was the NA-16, which in 1935 won North American Aviation (NAA) the contract to supply the USAAC’s basic trainer. The open cockpits and fixed undercarriage of this prototype were quickly replaced with canopies and retractable gear to create the NA-18 (or BT-9 as the US Army called it), whose fuselage – though still using the fabric-covered steel-tube construction of the prototype – was extended by five inches to improve the trainer’s longitudinal stability. However, a number of early training accidents involving tip-stalling indicated the need for further modification and the BT-9 was initially fitted with leading edge slats at the tips to increase their critical angle of attack – the angle at which they would stall – and later with revised outer wing sections that incorporated 2º of wash-out.


NA-16 (X-2080), which first flew in April 1935, pictured at Wright Field prior to flight testing and evaluation.

The resulting airframe, the NA-26 – which could accommodate a pair of .30in guns in the engine cowling, and another in the rear cockpit – was then presented not as a basic trainer, but as a basic combat aircraft, the BC-1. Coinciding, as it did, with the US government’s decision to focus defence spending upon fighters and bombers, this timely change of emphasis allowed the USAAC to create a new non-trainer procurement category, for which it promptly invited tenders. Handily, NAA and the BC-1 won the contract, and the NA-26 airframe went on to provide the platform for every subsequent variant right the way through to the post-war AT-6s that served in the Korean and Vietnam wars.

To adapt the NA-26 to RAF requirements, North American fitted it with British instruments, radios, and spade-grip control columns, provided for the installation of a .303 machine gun in the right wing, and hitched the whole lot to a 600hp Pratt & Whitney engine. The result was the Harvard Mk.1, which Britain ordered not only for the RAF but also for the New Zealand and Canadian Air Forces. Interestingly, the Australians had achieved almost exactly the same training solution by a very different route: in 1936, its Commonwealth Aircraft Corporation (CAC) had gone in search of a modern trainer that it could build under licence and had settled upon North American’s machine. The CAC-built NA-33 – which, like the Harvard, was essentially a BC-1 – took to the air in 1939, and served as the Wirraway with the RAAF for the next 20 years. What’s more, in 1942 a Wirraway chalked up the only air-to-air kill credited to any of the many variations on North American’s design when Flt Lt John Archer managed to sneak up on a Japanese Zero and down it.


An early production AT-6, the AT standing for Advanced Trainer.

From 1939 onwards, the threads of these NA-16 derivatives – which had multiplied through NAA’s development of different models for the US Navy and Army, and for export – began to recombine: the Navy’s SNJ-1, which arguably represented the best of different Army aircraft up to that point, was coupled to the Harvard’s 600hp P&W engine, and the angular fin and rudder of the USAAC’s BT-14. The result was the BC-1A (or BC-2 as it was first labelled), the aircraft known as the Harvard Mk.II to the RAF, for whom they were built by the Canadian firm, Noorduyn Aviation.


At the same time, the US Army was having second thoughts about that ‘basic combat’ category and, concluding that the North American was really an advanced trainer after all, changed the BC-1A’s ‘mission code’ to advanced trainer, or AT-6.

Built by Noorduyn Aviation of Canada, the AT-6A was supplied to USAAF as the AT-16 and the RAF / RCAF as the Harvard IIB.

Notwithstanding a number of specials and export-only designs – the unique V12-engine XAT-6E, for example, the aluminium-fuselage BC-1A Super Harvard, and the razor-backed NA-50, a single-seat fighter built for the Siamese Air Force – this process of convergence and standardisation continued into the late ‘40s. Indeed, when the USAF and US Navy were ordering their AT-6As / SNJ-3s, the aircraft were so similar that the Army apparently accepted the first SNJ-3 on the Navy’s behalf.

From 1947 onwards, the last aircraft belonging to the line founded by the NA-16 were labelled neither ‘advanced’ nor even ‘basic’, but simply T for trainer, though the fact that the majority of T-6s were built at NAA’s plant in Dallas, Texas, gave rise to the catch-all name ‘Texan’. For the British, however, the Harvard remained the Harvard, whether it was a Canadian-built Mk.IIB or a Mk.III made in Dallas.

Such was the utility value of these aircraft that in 1948 more than 3500 T-6s were still in service in the United States alone, where a remanufacturing programme further extended their life by upgrading old T-6s and SNJs to produce the final iterations – the T-6G and SNJ-7. While the Harvard Mk.IVs which served with the post-war RAF had broadly the same specification as the T-6G, production again reverted to Canada and Canadian Car and Foundry, the peacetime successor to Noorduyn Aviation. But that’s not the end of the story for the service career of the AT-6 – or Harvard, T-6, call it what you like – didn’t finish when these production lines were closed. Rather, the aeroplane went with the RAF to Malaya in the ‘50s, served as a forward air controller in the Korean War, and remained in service with some US departments well into the ‘60s. All told, around 15,000 NA-16-derived aircraft served with 55 air forces, giving North American’s aircraft a Kalashnikov quality: name any of the conflicts and trouble spots in the decades after W.W.II, from Israel to Laos, and virtually all of the African anti-colonial struggles, and you’ll find a T-6 / Harvard was involved there in one way or another.


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