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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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    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, 1920 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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Squadron Pennant Comes Home

Written by Carl Mills.

110-squadron-flag-news300x200CAHS Member Carl Mills discovered the 110 (400) Squadron pennant in 2010. After “many telephone calls and some luck,” he found the 71-year-old original in Albany, NY just in time for the squadron’s 80th anniversary next year. Read about his experience and the history behind it.



By Carl Mills

Many of you do not know about this flag, actually a pennant, which I discovered last year and, after many telephone calls and some luck, found the seventy-one year old original in Albany, NY.

400 Squadron, formed in 1932, was initially 10 Squadron when it flew from the Trethewey Farm Airfield (aka de Lessep Field) in Toronto from 1934 to 1939.  The Squadron was renumbered to 110 in 1937 and, when deployed to war in 1939, still carried that number.  In mid-1941, while in the UK, it was renumbered to 400.

When ordered to War in late 1939, the Squadron first deployed to Rockcliffe (Ottawa, ON) for conversion to the Lysander aircraft.  The new CO at that time was S/L W.D. Van Vliet.  By early February 1940, the Squadron was ready to depart to the UK, first by rail to Halifax and then by steamship across the Atlantic.  The squadron was the first RCAF unit to go overseas and they were given an official send-off, in Ottawa, by the Prime Minister and the Min. of  National Defence.

At that time, S/L Van Vliet was presented with the one-of-a-kind 110 Squadron pennant.  A 12-page Canadian National Geographic article with 20 images was published in June 1940 about the activities of the Squadron from Rockcliffe to the arrival in the UK.  On the front page was an image of the pennant.

I discovered this article some time ago and finally decided to either make a replica or find the original.  We were able to get a good B&W from the War Museum in Ottawa and this was scanned into an accurate drawing.  In January, I found the original pennant with the Van Vliet family in Albany, NY.  This past Thursday, I drove to Albany (and back - almost 1,500 kms) and returned the pennant to Toronto.  I departed at 0600 and was home just before midnight.

It was an exciting moment when I unfolded this historic item at the Van Vliet home.  I was also able to get a copy of G/C Van Vliet’s six logbooks and several photos, for the era that he was CO, are being gathered by the family.  Unfortunately, G/C Van Vliet died from a heart attack at age 39 in 1942 while serving as the Air Officer Commanding the Western Region of Canada.  He is buried at Beechwood Cemetery in Ottawa.

The pennant measures 20 inches x 30 inches (50 X 60 cms).  It is identical on both sides and is made from a wool-weave type of material.  It is see-thru when held up to the light.  There are about a dozen thin spots or very small holes but, otherwise, it is in pristine condition with no apparent fading.

The pennant is now stored in an archival-quality full-sized and clear plastic envelope.  This, in turn, is kept in a full-sized and flat brief-case shaped wooden carrying case with a handle.

Next, I will have the pennant professionally evaluated for possible restoration (or not) and mounting.  I will be negotiating to have the pennant kept at the National Air Force Museum in Trenton and negotiating with the family for permanent retention in Canada (this is partially complete).  Beyond the donation from the Air Force Assoc., there will be a fund raiser to complete the project - estimated at $1,300.  There will also be a few full-sized replicas made; for the family and the squadron.

I would like to thank the Van Vliet family in Albany, NY for their kindness and trust: Ilene Hoerning and Claire Van Vliet (daughters), Audrey Thomas (granddaughter) and Walt Hoerning (grandson).  I would also like to thank Peggy Van Vliet of Ottawa and Locklan (Rocky) Van Vliet of Carrying Place, ON for their great assistance in finding the family. And, Dr. Georgiana Stanciu, Curator at the National Air Force Museum in Trenton, ON for their interest.  Thanks to Eric Fernberg of the Canadian War Museum in Ottawa and Peter Elliot of the RAF Museum in Hendon for their valuable comments to the project.

Thanks to The Air Force Assoc. Trust for their willingness to partially fund this project.  Thanks to Harold E. Wright who has provided further research and documentation from the National Archives in Ottawa. And lastly, thanks to Ron Wylie who autographed and donated a 400 Squadron history book to the Van Vliet family.