Blackburn Dart

Background During late 1919, Blackburn commenced design work on what would become the Dart; it was initially pursued as a private venture. Around this time, the Air Ministry had reissued its requirement for a new carrier-based torpedo-bomber that would replace the Sopwith Cuckoo, the standard torpedo bomber of the era being flown from the aircraft carriers of the Royal Navy. It was a relatively large single-seat biplane, which was in several respects considered to be a conventional design for the era. The tail unit had a braced tailplane and fin with a balanced rudder. The divided landing gear had main wheels on shock absorber (oleo) legs that allowed the fitting of a standard torpedo below the fuselage. A novelty was the detachable mounting for the engine, which facilitated its replacement as a complete power unit and enabled its swapping in a matter of hours. By July 1920, the prototype Swift was sufficiently complete as to permit it to go on be static display to the public at the Olympia Aero Show but without a radiator or controls. On 9 May 1921, following the installation of a new engine, a stiffened cowling, and arrestor claws on the stub axles, the prototype was dispatched to Gosport. The Dart had its wingspan reduced by , which brought the twin tips closer to the outboard interplane struts, was the most visually distinctive change. A series of competitive trials against the Handley Page Hanley were conducted at Gosport, during which the Dart emerged as the victor and became the new standard torpedo bomber of the Fleet Air Arm. An initial production contract for 26 aircraft was issued to Blackburn. During March 1922, deliveries commenced, having been built at Blackburn's Olympia Works and tested at Brough. An export model of the Dart retained the Swift name. This was powered by the Napier Lion engine, capable of producing up to . The aircraft's ability to carry up to of bombs or an torpedo was attractive to international operators. Seven aircraft were built as the Swift Mk II, two for the Japanese Navy, three for the Spanish Navy and two for the United States Navy. The U.S. Navy aircraft were designated Swift F by Blackburn and Blackburn BST-1 by the U.S. Navy; following competitive trials held during 1921, the U.S. Navy chose the Douglas DT-2 instead. The aircraft were retained in San Diego for a time, being used for experimental purposes. ==Operational history==

During 1923, the Dart T.2 entered service with the Fleet Air Arm (FAA). The first units to receive the type were No 460 Flight aboard stationed in the Mediterranean and with 461 and 462 Flights on based in home waters. Shore training was conducted by "D3" Flight at Gosport. According to the aviation author Audrey Jackson, the Dart played an important role in the FAA's development and perfection of techniques for torpedo-bombing. Perhaps the most notable event in the career of the Dart occurred on 6 May 1926 when Air Commodore G. H. Boyce became the first pilot to carry out a night deck landing, alighting his Dart aboard Furious. ==Variants==

;T.1 Swift :Prototype torpedo bomber, one built. ;Dart :Prototype; one built. ;T.2 Dart :Initial production variant – 117 built (three converted to two-seat trainers). ;Swift Mk II :Export version – seven built. ;Swift F :US Navy designation of the Swift Mk II for evaluation (would have been designated the BST-1 if ordered). ;T.3 Velos :Two-seat variant for the Greek Navy – 16 built (12 under licence in Greece). ;T.3A Velos :Company demonstrator and trial aircraft – six built. ==Operators==

; • Imperial Japanese Navy (as Swift Mk II) ; • Spanish Navy (as Swift Mk II) ; • North Sea Aerial & General Transport Company (as T.3A Velos) • Royal Air Force (Fleet Air Arm) ; • United States Navy (as Swift F) ==Specifications (Dart T.2)==