| The North American AT-6 Texan
by Earl Swinhart
|North American AT-6C Texan USAAF.|
North American Aviation (Rockwell) has in its archives an ordinary sheet of paper with handwritten numbers and a few hand-drawn doodles vaguely resembling parts of an aircraft scrawled across it and dated "dec. 10, 1934"[sic]. On that sheet, over a cup of coffee, J.H. "Dutch" Kendelberger, J.L. Atwood and H.R. Raynor sketched out what North American would come to call the "NA-16", Granddaddy of one of the greatest aircraft of all time - the T-6 "Texan".
The T-6 is known by a variety of names; the "Texan" by the US Air Force and US Navy, the "Harvard" by our British and Canadian allies, and the "Wirraway" by the Aussies.
Talk to ten different people with first-hand knowledge of a particular aircraft and you get ten different accounts of the same aircraft. Not so with the T-6 "Texan". All agree the Texan had some terrible flight characteristics (fairly normal for a low wing monoplane of the mid 30's), all see eye-to-eye on the subject of landing in a crosswind (don't do it unless there's no other choice and then be prepared for a rough ride!). And all agree there was never a better aircraft built for training fighter pilots.
The records show the Texan was used to train more military pilots from more countries of the world than any other aircraft ever built before or since.
Almost every country in South America bought the T-6 for their air forces, as did most European countries. China and the Southeast Asian countries (including Japan) bought the Texan. Many of these countries also bought manufacturing rights. Japan bought manufacturing rights and was suspected of using some design features in their own aircraft during WWII. More than a few of these Texans were modified with one or two fixed, forward firing guns and a flexible rear gun and used as combat aircraft, especially South America where wars were sometimes fought over the outcome of soccer games.
The NA-16 progressed from that crude, hand-drawing of December 1934 to a flying aircraft in less than four months (a performance which would later win North American a contract to build the first P-51 "Mustangs" for the British). On April 1, 1935 the NA-16 with the identification number "X2080" was sitting on the runway at the Dundalk, Maryland factory with Pilot Eddie Allen at the controls. (Allen was later killed testing the Boeing B-29).
|North American SNJ-5 US Navy|
This first NA-16 had an open tandem cockpit, leading some historians to believe that the first NA-16 tested by the military had open cockpits. However, a picture taken on April 18, 1935, just a little over two weeks after its maiden flight, and while undergoing evaluation at the Army's Wright Field Test Facility clearly shows "X2080" with a greenhouse canopy.
As evaluated at Wright Field, it was a tandem 2 place, low wing monoplane with fixed undercarriage, a wingspan of 42 feet (12.80 meters) and a Wright Whirlwind R-975 radial engine of about 400 horsepower (299 kW) which could pull it along at a snappy 172 mph (276.80 kph).
However, at "The U.S. Army Air Corps Basic Trainer Competition" held during the latter part of May 1935, the NA-16 failed to cause any raised eyebrows. It was up against stiff competition from aircraft built by Seversky and by Curtiss-Wright, both of which simply outclassed the North American entry. It therefore must be surmised the USAAC saw something in the NA-16 which wasn't evident in the test results, for they gave North American an order for 42 copies of the plane with minor modifications. The fact that North American's parent company was General Motors probably had more than a little influence on the USAAC decision. The USAAC designated the aircraft the "BT-9".
North American BT9
Aircraft Year Book 1939
Even during the USAAC competition, North American was hard at work on an export version of the Texan. The NA-18 was intended to be an omnipotent craft, capable of being modified into a single place fighter or dual place bomber, as well as a training craft. The original NA-16, Serial Number NA-16-1 (ID #X-2080) was a veritable chameleon. All these different craft were brought about by seemingly instant modifications to this single airframe. The final modification was the installation of twin .30 caliber (7.62 mm) M-1 machine guns on the engine cowling thereby producing the one and only NA-18 which was finally sold to the Argentine Army on October 7, 1935.
Forty-Two USAAC BT-9s were delivered beginning in early October 1935. These craft were basically identical to the NA-16. The cockpits were somewhat wider and the instrumentation was more complex. The aircraft contained no armament.
It was this aircraft that earned the Texan a reputation for it's wicked stall and spin characteristics. The Pilots Manual cautioned "Do not intentionally spin the aircraft more than one turn." Several fixes were tried; leading edge slats, wing slots, "drooped" wingtips etc., without much improvement.
By the time the BT-9A was on the drawing boards, several important changes were to be made. The dash 9A had the same armament as the dash 9 except provisions were made for under-wing bomb racks.
Someone came up with the idea of twisting the tip of the leading edge of the wing down by 2°. This brought about better stall qualities. When combined with a modified rudder and a lengthened fuselage, the problem was brought somewhat under control, although it was never solved completely.
BT-9Bs were modified to put more of the "B" back in "Basic Trainer". There was no provision for armament. Improvements learned from the dash 9A were incorporated. In all other respects, the 9B was very similar to the 9A. North American built approximately 120 of these craft which were distributed to the USAAC training fields throughout the US. A few were stationed in Hawaii.
The BT-9C was the first Texan to have retractable landing gear. This feature was brought about in part by the USAAC desire to make operation of training aircraft more realistic. In keeping with this desire, all the older Texans were fitted with a "dummy" switch to simulate operating the landing gear even though they were fixed. When a student was flying the fixed gear version he was instructed to "raise the gear" on take-off and informed that he had landed "gear up" when the he failed to operate the switch on landing these older types. Of course it was much more realistic if he failed to operate the switch on the 9C!
The 9C retained the Wright R-975-7 radial engine of earlier models. Production of the BT-9C totaled more than 100 aircraft.
It was about this time in the evolution of the Texan (mid 1937) that the USAAC began to realize the BT-9 series would be more aptly designated a Basic Combat Trainer (as opposed to simply "Basic Trainer"). It was the advanced characteristics of the BT-9C (retractable landing gear, comparatively high top speed etc.) which convinced USAAC training command to solicit bids for aircraft in the "Basic Combat Trainer" category which led directly to the "BC-1"
Little is known of the BT-9D except that at least one example was built and it may have been a test bed for advanced modifications. The 9D almost certainly contributed very little to the overall evolution of the Texan.
There was a bewildering array of models between the BT-9 and the BC-1, including a "BT-10" and "BT-14". It is unclear whether any of these models were actually delivered to the U.S. armed services. There are records of over 250 BT-14s being built. Some or all may have been delivered to our allies or to South American countries.
The coming of the BC-1 brought the standardization of the classical AT-6 lines. Changes would be made to internal and minor external elements of the aircraft, but from here on, the shape was unmistakably "Texan". Further refining resulted in an order for a little over 80 copies each of the BC-1 and BC-1A. The BC-2 was the last of the BCs and only 3 copies were built. These were basically identical to the T-6.
By early 1939, the USAAC became aware that their Texan had grown up and could (in reality) no longer be classified as a "Basic" training aircraft. Pilots were required to have basic flight knowledge before ever taking a seat in the Texan. It was therefore decided to reach back in time about ten years and reintroduce the "Advance Trainer" designation, just for the Texan.
The first AT-6s were delivered to the USAAC near the middle of 1939. They were powered by the Wright
R-1340-47 engine of 600 hp (447.8 kW) which could move it along at over 200 mph (321.9 kph). They had provisions for mounting a fixed, synchronized .30 caliber machine gun over the right side of the engine cowling and flexible in the rear cockpit facing aft.
With prospects for peace in Europe looking murkier by the day, the US Army Air Corps began placing record orders with North American for the AT-6. Where the Inglewood plant was accustomed to orders of ten to 75 aircraft, suddenly they were faced with the problem of turning out a thousand or more copies per "batch".
It became apparent a new plant would have to be built to take some of the pressure off of Inglewood. The site chosen was Dallas, Texas, where the AT-6 acquired the name "Texan". Dallas began production in December 1940 and turned out by far the largest quantity of AT-6s of any North American plant..
None of the records agree on just how many Texans were built. Sometimes the USAAC would buy hundreds of surplus AT-6s and have them extensively rebuilt. And sometimes these aircraft were counted as new. On the other hand, due to North Americans bewildering model designations, "charge numbers" and service numbers, large quantities were actually built, but then redesignated as a different model or charge number, and somewhere along the line, historic information on the actual production numbers was lost. The best guess is somewhere between 12,000 and 15,000 Texans were built in the nine year production run of the T-6 Texan which ended in early 1944.
During its lifetime, the Texan was used as a bomber, fighter, a spotter ("mosquito"), a strafer, a "Brass Taxi" and a patrol craft, as well as an "Advance Trainer". Handling characteristics eventually improved to the extent that the instruction book could state "It will take approximately 4½ turns to recover from a spin" a far cry better than the original "Do not intentionally spin the aircraft more than 1 turn".
Every year, the T-6 can be spotted at air races around the country, particularly the famous Reno Air Races. So many come to Reno that they have their own category race where other craft are not allowed.
The Texan was (and is) a true American classic.
|North American T-6G Texan|
|Wing span:||Wing Span: 42 ft 0 in (12.8 m)|
|Length:||Length: 29 ft, 6 in (9 m)|
|Height:||Height: 12 ft, 4 in (3.8 m)|
|Wing Area:||253.7 ft² (23.6 m²)|
|Empty:||4,158 lbs (1,886 kg)|
|Max Gross:||5,617 lb (2,548 kg)|
|Maximum Speed:||212 mph (341.2 kph)|
|Cruising Speed:||170 mph (274 kph)|
|Service Ceiling:||21,500 ft (6,553.2 m)|
|Maximum Range:||750 mi (1,207.0 km)|
|One Pratt-Whitney 550 hp (410 kW) Wasp R-1340, 9 cylinder, air cooled radial engine.|
One fixed, synchronized .30 caliber M-1 machine gun firing |
forward and, one flexible .30 caliber (7.62 mm) M-1 facing aft.
© The Aviation History On-Line Museum. All rights reserved.
Created January 7, 2006. Updated January 20, 2013.