Circa mid 1930 America along with other countries was in the midst of modernising aircraft to be capable of operating in hot weather terrain as the western United States for desert testing, and some other place for low temperature cold weather testing. In the latter case Alaska offered the ideal spot more than any other state. Ladd field provided a suitable place for US Army Air Corps to test aircraft and equipment under extreme cold weather conditions.

 Two B-17s were set ready at the Sacramento Air Depot for cold weather experimental work. When preparations were complete six officers and eighteen men that comprised crew of two aircraft departed for Alaska. They were met by Maj.Gaffney on their arrival at Ladd airport. The crew bundled in fur-lined boots and flying togs lumbered out of the two planes. They expected to find natives at Fairbanks dressed as if living in ice boxes; instead they were dressed in clothing normally found in lower 48 degrees Fahrenheit.

 They began work in earnest and eventually sufficient data has been gathered concerning northern conditions to warrant a flight to the materials division at Dayton Ohio and a conference with Air Corps engineers there. The Air Corps was particularly interested in ski operations and development of ski for all types of aircraft. These were still a somewhat limited testing and in conjunction with the advice given by the local experienced Alaskan pilots several tentative conclusions were reached. Only light aircraft could operate with any regularity from unprepared areas. The report also suggested that further testing be conducted at a later date.

 Two B-17s and two Curtiss YP-37s had arrived with Maj.Gaffney in April 1940. One YP-37 and a B-17B were lost during the first season of testing. In spite of all the flying crew still managed to log over 800 hours of flying time. By October Ladd field provided the base for two of each of the current aircraft. They had winterisation equipment incorporated through either production or modification. In spite of requests and varied promises, deliveries of some aircraft were delayed. One of these aircraft a YP-37 that was prepared for operations in Alaska had bright international orange painted on standard areas to the forward fuselage and wings for any eventual accident in the snow terrain and thereby could be easily detected from the air.

 The cold weather testing during the cold season was not a complete waste. They learned that major difficulties was not with aircraft but with the personnel, since it was difficult to maintain the equipment while wearing the bulky clothes necessary to keep them warm. Aircraft that have been exposed to extreme cold should be left outside. Constant movement in and out of the hangar caused aircraft to sweat and this compounded problem of operation. The alternative thawing and freezing caused hydraulic problems, broken seals and fractures windshields and canopies. A lesson learned well, for modern aircraft are either hangared or left on the ramp, but they are not normally shuttled around. The testing and experiments also relied on analysis of cold weather operations of allied and even enemy nations. Results of the German Air Force against Russia during the winter of 1940-41 and lessons learned by th Air Transport Command in flying aircraft over the Northern ferry route were also studied. Russian officers who had fought against Germans during periods of extreme cold weather described their successes against Germans were due to German aircraft that were not capable of operating under extreme low temperature.

 The results indicated that as a basic requirement of combat aircraft, the Army Air Force had to be capable of operations under extremely low temperature conditions, as low as minus 65 Fahrenheit. In addition to testing aircraft, the cold weather test detachment also performed extreme testing on clothing and other materials.

 The experimental Allison-powered XP-37 produced in 1937 therefore gave its share in the cold weather tests conducted in Alaska. Although the XP-37 engine/supercharger combination was quite troublesome the USAAC realised the potential of the concept and apart from the cold weather tests, there were thirteen service test aircraft with the V-1710-21 engine, revised nose contours, a 25” lengthening of the fuselage to the cockpit for balance and directional stability purposes. Still it was plagued with supercharger problems and all but one went out of service or retired by early 1942.  A parallel design was the XP-40 which proved more suitable and was developed into the extensive P-40 fighter series, thereby bringing an end to the brief history of the YP-37. 

The Curtiss YP-37 comes in a polythene pack and is quite a basic kit consisting of two fuselage halves and a conical spinner all vac formed in white plastic. The pack also includes a vac form clear canopy. This was unfortunately damaged but with some effort it still could be salvaged. An instruction sheet of an A4 size depicts a two tone picture of a typical completed model  and there is also a side view to suggest an operational silver overall livery of the type which was attached to the 10^th Air |Base Squadron, Chanute Field, Rantoul, Illinois in 1939. Two smaller view scale plans give indication of work needed to the wing roots. 

The fuselage parts are first cut from the backing sheet and the edges are sanded to make a good centreline joint. Several ¼ inch plastic tabs were added along the inside of the joining edge. Internal cockpit details were added using parts from a kit of the P-75. The instruction suggests using a Revell or Heller Hawk 75 besides the Monogram kit for the provision of wings and undercarriage. Here are side air intakes on the front nose which were opened and a blanking piece was added to the inside of fuselage to avoid the see through effect. The interior was painted zinc chromate. I have used parts from the Monogram Curtiss Hawk 75A-3 Kit No 74007-0389. The wings and undercarriage were assembled and fitted to the vac form fuselage. This did not quite provided a perfect joint and some putty carefully applied produced a smooth faired wing root. The kit propeller was added and the conical spinner carefully cut shaped and inserted to the prop front. The prop was to fit at a later stage. Small fairings were added to the leading edge in way of the wing root using Revell Plasto filler. Gun positions were drilled at the upper nose so that small hollow metal tubes were inserted to simulate the front end of nose guns. Finally a tail wheel added. 

This was another type of aircraft that spent time in Alaska's wonderland mainly for cold weather trials. In fact I chose to finish in the colour scheme in which it operated. Thanks to Lars Opland of Wasilla, Alaska who sent me very relevant information about the YP-37’s Alaskan connection as well as a picture of the aircraft in the vivid markings. The conspicuous colours consisted of bright red/orange areas at nose, and wing tips, not much different from the markings applied to the Martin B-10 that appeared on MM some time ago. I have used Model Master Italian red 2719E for the bright areas simulating a bright type of international orange. The rest of the aircraft was silver. The interiors were zinc chromate. A black serial number, wing walkways decal strip and black anti glare panel were added from spare decal box.

 This kit build was yet another aircraft that with an extra bit of research has evolved an interesting colourful livery which turned it into an eye catcher aircraft having a short life but interesting history behind it.

 Ref 1:  Top Cover for America, the Air Force in Alaska 1920-1983 by John Haile Cloe & Michael F. Monaghan.

 Ref 2:  “Arctic Warbirds” by Steve Mills

Carmel J. Attard

May 2008