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  • Plaque Celebrating Aviation History in Mount Dennis

    Saturday, July 15 - 10:45 am

    Hearst Circle and "The Wishbone" (Opposite Harding Park in Mount Dennis)

    Reception to follow at The Atrium, 12 Division Police Station, 200 Trethewey Drive, North York

    This event is a joint function of Heritage Toronto, CAHS (Toronto Chapter & National) and 400 Squadron Historical Society.  The plaque is honouring the airfield that hosted 1st flight over Toronto in 1910, the startup location of DeHavilland Aircraft in Canada in 1928 at this airfield and in 1932 the first operational base of the RCAF 400 "City of Toronto" Squadron as 10 Sqn and later 110 Sqn.

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    FINAL Invite Trethewey july15 545

    Background on the William G. Trethewey Property

    By Dr. Robert Galway

    This property was purchased by William Trethewey following his sale of two Silver mining properties that he discovered in Cobalt, Ontario on 1904. He and his brother Joseph O. Trethewey made millions in this transaction. William Trethewey came to Toronto and purchased 600 acres in Weston, near present day Jane St. & Lawrence Ave. in 1907 The Royal Automobile Club of Canada and the OML of which Trethewey was a member, asked for permission to use a portion of the property for an exhibition Air Meet. This took place July 9-16th, 1910 following closely on the heels of the initial Air Meet held in Pointe Claire, PQ.

    During the Toronto meet, French Aviator Jacques de Lesseps completed the first flight over the city of Toronto as he had done two weeks previously in Montreal. The Toronto flight occurred on July 13, 1910. This is the basis for recognizing Jacques de Lesseps on the Heritage Toronto Plaque that will be unveiled this summer on July 15, 2017.

    However, this is not the sole reason for recognizing the contribution that this plot of farmland made to Canadian aviation history.

    Following the Air Meet of 1910, the property became the center of early aviation activity in Toronto. Indeed, it became known as de Lesseps Field. In 1928 de Havilland UK decided establish a manufacturing center in Canada. They were persuaded to do so because of the success they had met in selling the DH60 Moth to the Ontario Provincial Air Service. In their search for a suitable property, they were put in touch with Frank Trethewey who had inherited the property on his father’s demise in 1926. Trethewey leased a parcel of the land to de Havilland and with the incorporation of de Havilland
    Canada was appointed to the DHC Board.

    Consequently, the Trethewey property became the first manufacturing site of de Havilland. In fact the first building used to assemble the DH60 series was the Trethewey Canning Shed made famous by the sketch completed by famous aviation artist, Robert Bradford.

    Frank Trethewey was given the opportunity to purchase DH aircraft at a significant “favored” price. He and his brother were RNAS veteran pilots. In the 1930's he was Chairman of de Havilland Canada.

    The establishment of de Havilland Aircraft on this property in 1928 is the second reason to grant historic recognition to this property.

    Frank Trethewey not only over time purchased three aircraft from DHC but went one step further and joined the RCAF. This led to the establishment of the RCAF Squadron 10/ 110 on Trethewey Field. Frank Trethewey was one of the first four flying officers appointed to the Squadron. In 1940 he was appointed commanding officer of Base Trenton.

    The squadron was formed in October 1932 as 10 (Army Cooperation) Squadron and began flying in 1934 at the Trethewey Farm airfield (aka de Lesseps Field) in Toronto. In April, 1935, the City of Toronto adopted the squadron which then became officially known as “10 (City of Toronto) Squadron”. In 1937, the squadron was re-designated “110 (City of
    Toronto) Squadron”.

    The squadron flew five basic types of aircraft, all biplanes, from Trethewey until late 1939 when it deployed to Rockcliffe. During the Trethewey era, the squadron was involved in recruitment and flight training. At Rockcliffe, the squadron underwent conversion to the Canadian-built Westland Lysander until mid-February 1940. The squadron then deployed to the UK as the first RCAF squadron to enter the Second World War.

    In the UK, the squadron was initially equipped with the Lysander III and was involved in the Army Co-op and photo reconnaissance role. The squadron was active in the Dunkirk evacuation (27 May - 3 June 1940) but not directly involved in the Battle of Britain (10 July - 31 Oct. 1940). In mid-1941, the squadron was re-designated “400 Squadron”.

    Today, the Squadron is located at Camp Borden and is the main maintenance centre for maintenance of the RCAF's Tactical Helicopter Squadrons.

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  • My Snowbirds Flight - Aide-Memoire

The Bell P-39 Airacobra in the RCAF

The Bell P-39 Airacobra in the RCAF

P-39 RCAFBy Bill Zuk

In 1939, as war clouds brewed over Europe and the Far East, Canada was ill-prepared for war. The RCAF, in particular, relied on a handful of obsolete Grumman Goblin 1 two-seat biplanes as front line fighters, although Canada Car and Foundry in Fort William (where the Chief Engineer Elsie MacGill became known as the “Queen of the Hurricanes”) had already started the production of a small run of Hawker Hurricanes. Eventually 1,300 Hurricane Mk X series were manufactured, but the orders were intended for RAF use.

In mid-May 1940, Canadian and US officers watched comparative tests of a Curtiss XP-40 prototype and a production standard Supermarine Spitfire Mk 1, at RCAF Uplands. Ottawa. While the Spitfire was considered to have performed better, it was not available for use in Canada, and the RCAF still wanted to consider other alternatives.

Throughout the early stages of the Second World War, the growing tension between Japan and the US resulted in the need to strengthen and upgrade Canada's Western Air Command. With all available Hurricanes committed to Europe, orders for 144 Bell P-39 Airacobra fighter aircraft had been placed to fulfill the fighter defence role in this theatre.

CAHS Vol 42  No4The Bell P-39 had a curious genesis, designed as an interceptor and incorporating the latest technology, yet handicapped by a decision to delete the turbo-supercharger that had made the prototype a world-beater. The innovative design was the first fighter in history with a tricycle undercarriage and the first to have the engine installed in the center fuselage, behind the pilot, creating a streamlined, futuristic fighter. Despite the performance of the XP-39 reaching nearly 400 mph at 20,000 ft in tests, USAAC officials and company founder Larry Bell made a fateful decision to rely on the single-stage, single-speed supercharger that effectively limited the new fighter to a low-altitude role.

On April 3, 1940, an order for 200 P-39s were placed by Armée de l'Air but were undelivered when France capitulated, leading to the RAF taking over the consignment in September 1940, adding to the total order of 675 Bell Model 14s (Bell P-39D), initially named “Caribou”, later to be redesignated as the Airacobra 1. Test results were disappointing, falling below that of the current Hurricane and Spitfires in service with inadequate rate of climb and performance at altitude, adding to a plethora of other concerns, none more troubling then a cramped cockpit and poor egress in the event of bailout. The operational debut of the Bell fighter with No. 601 Squadron was limited to one combat sortie flown, against enemy barges at Dunkirk, before the type was retired. All remaining Airacobras, redesignated P-400s, were diverted to US Pacific fighter squadrons.

Although not related to the RCAF eventual cancellation of its order, the RAF’s rejection of the Bell Airacobra must have played a role in acquiring the Curtis P-40 Kittyhawk fighter that was ordered to meet home air defense requirements. In all, eight Home War Establishment Squadrons were equipped with the Kittyhawk: 72 Kittyhawk I, 12 Kittyhawk Ia, 15 Kittyhawk III and 35 Kittyhawk IV aircraft, for a total of 134 aircraft. These aircraft were mostly diverted from RAF Lend-Lease orders for service in Canada and arrived in time to see duty in the Aleutians and Alaska.

In 1942, the Imperial Japanese Navy occupied Attu and Kiska in the Aleutian Island chain and Nos. 14, 111 and 118 squadrons flying the Kittyhawk I were involved in the drawn-out campaign. On 25 September 1942, S/L Boomer shot down an A6M2-N “Rufe” fighter at Kiska. During the final stages of Japanese attacks against North America, RCAF Kittyhawks would shoot down a total of three balloon bombs.

Bell P-39s were fated never to serve with the RCAF, although thousands would eventually make their way through Canada via the Northwest Staging Route airfields as the fighters made their way to the USSR, where the fighter would eventually make its mark as a premiere low-altitude dogfighter.

For more information on the Curtiss P-40 in Canadian service, see: “The P-40 in RCAF Service” by Hugh Halliday, CAHS Journal, Volume 4, No. 2, Summer 1966. A cover illustration, “Red Stars over Edmonton” by Tony Cashman, is in the CAHS Journal, Volume 42, No. 4, Winter 2004 showing Bell P-39s in Russian markings over Edmonton’s Legislative Building.