Operational History
On 4 February 1928, a contract was placed for three Iris III aircraft, similar to the Iris II but with fabric covered metal wings. The Iris II, meanwhile, continued in use, setting out on another long-range cruise on 27 September, carrying Sir Philip Sassoon, the Under-Secretary of State for Air and Air Commodore Sir Arthur Longmore on a tour of RAF Stations of the Mediterranean and Middle East. It reached Karachi on 14 October, finally returning to RAF Calshot on 14 November, having flown a total distance of 11,360 mi (18,290 km) with a flight time of 125 hr 5 min.
The first Iris III flew on 21 November 1929, with the three Iris IIIs equipping No. 209 Squadron which reformed at RAF Mount Batten, Plymouth in January 1930. 209 Squadron continued the pattern of long-range flights carried out by the Iris II, with one Iris visiting Reykjavík in June 1930 to celebrate the 1,000th anniversary of the Icelandic Althing (parliament), and another making the first crossing of the Bay of Biscay by flying boat when visiting Lisbon in August 1930.
The first Iris III was destroyed in a fatal crash on 4 February 1931, resulting in a replacement being ordered. Although still an Iris III, this had a number of changes, being fitted with provision to carry a COW 37 mm gun in its bow. The weight of the Iris had grown considerably since the Iris I, and it was decided to replace the Iris III's Condors with more powerful (825 hp (615 kW) Rolls-Royce Buzzard engines to restore performance and improve reliability, with the three re-engined aircraft re-entering service in 1932 as the Iris V. The Iris II was also re-engined, being fitted with three 800 hp Armstrong Siddeley Panther radial engines, with the centre engine in a pusher configuration to become the Iris IV.
The Iris Vs were replaced in squadron service in 1934 by the Blackburn Perth, four very similar Buzzard-powered aircraft closely based on the Iris. One of the Iris Vs was converted for use as a testbed for the Napier Culverin, a licence built Junkers Jumo 204 diesel engine, flying in this form in June 1937 and continuing flight trials until April 1938.
Read more about this topic: Blackburn Iris
Famous quotes containing the word history:
“The history of modern art is also the history of the progressive loss of art’s audience. Art has increasingly become the concern of the artist and the bafflement of the public.”
—Henry Geldzahler (1935–1994)