The Blackburn Dart was a carrier-based
torpedo bomber
A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the First World War almost as soon as aircraft were built that were capable of carrying the weight ...
biplane
A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...
designed and manufactured by the British aviation company
Blackburn Aircraft
Blackburn () is an industrial town and the administrative centre of the Blackburn with Darwen borough in Lancashire, England. The town is north of the West Pennine Moors on the southern edge of the Ribble Valley, east of Preston and north- ...
. It was the standard single-seat torpedo bomber operated by the
Fleet Air Arm
The Fleet Air Arm (FAA) is one of the five fighting arms of the Royal Navy and is responsible for the delivery of naval air power both from land and at sea. The Fleet Air Arm operates the F-35 Lightning II for maritime strike, the AW159 Wil ...
(FAA) between 1923 and 1933.
Work on what would become the Dart started in 1919 as a private venture. Originally known as the ''T.1 Swift'', it performed its
maiden flight
The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets.
The maiden flight of a new aircraft type is alwa ...
in September 1920. Three aircraft were ordered for evaluation purposes to fulfil
Air Ministry
The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of State ...
Specification 3/20, which received the name ''Dart''. First flown in October 1921, its performance quickly impressed officials and a production order was issued to Blackburn on behalf of the FAA. The ''Swift'' name was retained for the pursuit of export sales. Limited quantities were supplied to multiple overseas operators, including the
Japanese Navy
, abbreviated , also simply known as the Japanese Navy, is the maritime warfare branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. The JMSDF was formed following the dissolution of the Imperial Japanese Navy (IJN) ...
,
Spanish Navy
The Spanish Navy or officially, the Armada, is the maritime branch of the Spanish Armed Forces and one of the oldest active naval forces in the world. The Spanish Navy was responsible for a number of major historic achievements in navigation, ...
, and the
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
. Additionally,
Greece
Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with ...
opted to procure a modified
seaplane
A seaplane is a powered fixed-wing aircraft capable of takeoff, taking off and water landing, landing (alighting) on water.Gunston, "The Cambridge Aerospace Dictionary", 2009. Seaplanes are usually divided into two categories based on their tec ...
variant of the aircraft, the
Blackburn Velos
The Blackburn T.3 Velos was a 1920s British two-seat coastal defence seaplane built by Blackburn Aeroplane & Motor Company Limited, Brough Aerodrome and the Greek National Aircraft Factory.
Design and development
The basic design of the Blac ...
, which was operated by the
Greek Navy
The Hellenic Navy (HN; el, Πολεμικό Ναυτικό, Polemikó Naftikó, War Navy, abbreviated ΠΝ) is the naval force of Greece, part of the Hellenic Armed Forces. The modern Greek navy historically hails from the naval forces of vario ...
as a torpedo bomber.
Design and development
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
The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of State ...
had reissued its requirement for a new carrier-based torpedo-bomber that would replace the existing
Sopwith Cuckoo
The Sopwith T.1 Cuckoo was a British biplane torpedo bomber used by the Royal Naval Air Service (RNAS), and its successor organization, the Royal Air Force (RAF). The T.1 was the first landplane specifically designed for carrier operations, bu ...
, which was the standard torpedo bomber of the era being flown from the
aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...
s of the
Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...
.
Blackburn's efforts were led by their chief designer,
Major
Major (commandant in certain jurisdictions) is a military rank of commissioned officer status, with corresponding ranks existing in many military forces throughout the world. When used unhyphenated and in conjunction with no other indicators ...
Frank Arnold Bumpus
Frank or Franks may refer to:
People
* Frank (given name)
* Frank (surname)
* Franks (surname)
* Franks, a medieval Germanic people
* Frank, a term in the Muslim world for all western Europeans, particularly during the Crusades - see Farang
Curre ...
; the design process was undertaken in close collaboration with the British engineering company
D. Napier & Son. This new aircraft was originally named the ''T.1 Swift''.
[Woodman 1996, pp. 2–3.][Jackson 1968, p. 139.]
It was a relatively large single-seat biplane, which was in several respects considered to be a conventional design for the era.
It was built around a central nucleus in which the centre fuselage, top center section, lower wing roots, and
undercarriage
Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include:
*The landing gear of an aircraft.
*The ch ...
attachments were all integrated into a single rigid structure entirely composed of steel tubing. This structure provided sufficient strength as to not only withstand the high stresses of carrier operations, but also carry a heavy concentrated payload, while also being relatively easy to maintain and repair.
A similar tubular structure was also used for the rear fuselage. The fuselage had an unusual humped appearance due to the decking forward of the pilot sloping sharply downwards to maximise forward visibility over the engine, which was particularly useful during landings.
The Swift was outfitted with
staggered two-bay equal-span wings that could be folded for storage aboard ship; this arrangement meant Blackburn was the first British company to address the issue of a foldable staggered wing cellule.
The centre section of the wing structure was steel, while the outer sections were composed of wood, all of which were covered by fabric.
Aileron
An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...
s were present on all four wings.
[Jackson 1968, pp. 139–140.] The tail unit had a
braced tailplane
A tailplane, also known as a horizontal stabiliser, is a small lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters and gyroplane ...
and fin with a balanced
rudder
A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...
. The divided
landing gear
Landing gear is the undercarriage of an aircraft or spacecraft that is used for takeoff or landing. For aircraft it is generally needed for both. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Martin ...
had mainwheels on
oleo legs that allowed the fitting of a standard torpedo below the fuselage.
[''Flight'' 7 May 1925, pp. 269–272.][Woodman 1996, pp. 3–4.]
One innovation of the design 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.
Another advanced feature was the presence of a fireproof
bulkhead between the engine bay and the
self-sealing fuel tank
A self-sealing fuel tank is a type of fuel tank, typically used in aircraft fuel tanks or fuel bladders, that prevents them from leaking fuel and igniting after being damaged.
Typical self-sealing tanks have multiple layers of rubber and reinforc ...
in the fuselage, which could accomidate up to 66 gallons of fuel; an additional gravity-fed tank housing up to 15 gallons was present in the centre-top section. While it was not necessary to jettison the undercarriage wheels prior to releasing the
torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...
, unlike some contemporary aircraft, they were releasable as to minimise the tendency for the aircraft to nose over during a forced water landing, for which floatation bags were present in the fuselage.
The undercarriage incorporated a triangular support structure, a lengthy support axle, and a
rubber
Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...
compression
shock absorber
A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically heat) which is then dissipated. Most sh ...
leg. Slings fitted to the top centre section were used to hoist the aircraft aboard ship.
[Jackson 1968, p. 140.]
By July 1920, the prototype Swift was sufficiently complete as to permit it to be statically displayed to the public at the
Olympia Aero Show, but was fitted with a non-functional
radiator
Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in cars, buildings, and electronics.
A radiator is always a ...
and without any controls.
At the time, the aircraft had already been placed on the British Government's
secret list, which meant that it could only be displayed without specialised naval equipment, such as its torpedo release apparatus. Thus, when exhibited, the torpedo had to be placed on the ground between the undercarriage rather than being placed in an operational position.
Into flight
![BlDart](https://upload.wikimedia.org/wikipedia/commons/4/49/BlDart.jpg)
During September 1920, the prototype Swift conducted its
maiden flight
The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets.
The maiden flight of a new aircraft type is alwa ...
; it reportedly almost crashed during the flight on account of its miscalculated
centre of gravity
In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may ...
.
[Mason 1994, p. 130.] This issue was successfully resolved by sweeping back the wings. Following these modification, the Swift proved largely satisfactory in flight; on 23 December 1920, it was brought to
RAF Martlesham Heath
Royal Air Force Martlesham Heath or more simply RAF Martlesham Heath is a former Royal Air Force station located southwest of Woodbridge, Suffolk, England. It was active between 1917 and 1963, and played an important role in the development of ...
for full performance trials by the
Aeroplane and Armament Experimental Establishment
The Aeroplane and Armament Experimental Establishment (A&AEE) was a research facility for British military aviation from 1918 to 1992. Established at Martlesham Heath, Suffolk, the unit moved in 1939 to Boscombe Down, Wiltshire, where its work ...
.
One requested change, made in January 1921, was the fitting of an enlarged
rudder
A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...
to improve directional control. By 20 April, all trials had been completed.
[Jackson 1968, p. 141.]
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
Gosport ( ) is a town and non-metropolitan borough on the south coast of Hampshire, South East England. At the 2011 Census, its population was 82,662. Gosport is situated on a peninsula on the western side of Portsmouth Harbour, opposite t ...
.
Shortly thereafter, the type's first deck landing was performed by the Canadian pilot Gerald Boyce onboard
HMS ''Argus''.
Having suitably impressed officials, Blackburn received an order for a further three aircraft to conduct service trials as per
Air Ministry
The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of State ...
Specification 3/20. These aircraft, which were equipped to
Admiralty
Admiralty most often refers to:
*Admiralty, Hong Kong
*Admiralty (United Kingdom), military department in command of the Royal Navy from 1707 to 1964
*The rank of admiral
*Admiralty law
Admiralty can also refer to:
Buildings
* Admiralty, Traf ...
requirements, received the name ''Dart''.
[Woodman 1996, p. 5.][Jackson 1968, p. 150.]
The Dart had its wingspan reduced by 2ft 11in, which brought the twin tips closer to the outboard interplane struts, was the most visually distinctive change.
Other modifications included the adoption of more powerful engines, either a
Napier Lion IIB
The Napier Lion is a 12-cylinder, petrol-fueled 'broad arrow' W12 configuration aircraft engine built by D. Napier & Son from 1917 until the 1930s. A number of advanced features made it the most powerful engine of its day and kept it in produ ...
or V engine that was mounted with a thrustline angled upward. The claw arrestor gear that had been fitted experimentally to the Swift prototype was also fitted as standard.
During October 1921, the prototype Dart performed its first flight; on 24 October, it was flown from
Brough to RAF Martlesham for full performance testing.
It reportedly handled well, in spite of its size, and even exhibited a then-remarkable stalling speed of 43 mph (69 km/h). The first prototype also participated in deck handling trials aboard ''Argus''. The second and third prototypes underwent various evaluations, most of which were performed at Martlesham.
[Jackson 1968, pp. 150-151.] A series of competitive trials against the
Handley Page Hanley were conducted at Gosport, during which the Dart emerged as the victor and thus became the new standard torpedo bomber of the Fleet Air Arm. An initial production contract for 26 aircraft was issued to Blackburn.
[Jackson 1968, p. 151.]
During March 1922, deliveries commenced, having been built at Blackburn's Olympia Works and tested at Brough beforehand.
Three additional batches of ten Darts each were produced between 1923 and 1924; a larger contract for 32 aircraft was issued in August 1924. As late as November 1926, more small orders for replacement aircraft were also received. Production to the Dart came to an close during 1928, by which point 117 aircraft had been produced for the FAA.
[Jackson 1968, p. 152.]
An export model of the Dart retained the ''Swift'' name. This was powered by the
Napier Lion
The Napier Lion is a 12-cylinder, petrol-fueled 'broad arrow' W12 configuration aircraft engine built by D. Napier & Son from 1917 until the 1930s. A number of advanced features made it the most powerful engine of its day and kept it in produ ...
engine, capable of producing up to 450 hp (340 kW). The aircraft's ability to carry up to 1,500lb of either bombs or a single 18-inch torpedo was attractive to international operators.
[Jackson 1968, p. 142.] 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 United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
. The U.S. Navy aircraft were designated ''Swift F'' by Blackburn and Blackburn ''BST-1'' by the U.S. Navy, however, following competitive trials held during 1921, the U.S. Navy decided not to proceed with an order, opting to purchase the
Douglas DT-2
The Douglas DT bomber was the Douglas Aircraft Company's first military contract, forging a link between the company and the United States Navy. Navy Contract No. 53305 of April 1, 1921, required only 18 pages to set out the specifications that ...
instead. The aircraft themselves were retained in
San Diego
San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...
for a time, being used for experimental purposes.
[Jackson 1968, p. 143.]
Operational history
![Blackburn Dart advert](https://upload.wikimedia.org/wikipedia/commons/d/df/Blackburn_Dart_advert.JPG)
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 deploying torpedoes.
During 1928, the Blackburn Dart flew with Nos. 463 and 464 Flights embarked on in the Mediterranean fleet.
The following year, a single Dart was delivered to
No. 36 Squadron (Coastal Defence Torpedo Flight), initially for smokescreen trials and later to form part of the complement of torpedo bombers in the first fully operational torpedo bomber squadron of the
Royal Air Force
The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and ...
.
Three Darts were converted into two-seat
seaplane
A seaplane is a powered fixed-wing aircraft capable of takeoff, taking off and water landing, landing (alighting) on water.Gunston, "The Cambridge Aerospace Dictionary", 2009. Seaplanes are usually divided into two categories based on their tec ...
s to provide advanced training at Blackburn's RAF Reserve School on the
River Humber
The Humber is a large tidal estuary on the east coast of Northern England. It is formed at Trent Falls, Faxfleet, by the confluence of the tidal rivers Ouse and Trent. From there to the North Sea, it forms part of the boundary between the ...
between 1925 and 1929. These conversions led to a new variant, the
T.3 Velos, which was procured by
Greece
Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with ...
as a torpedo bomber for the use of the
Greek Navy
The Hellenic Navy (HN; el, Πολεμικό Ναυτικό, Polemikó Naftikó, War Navy, abbreviated ΠΝ) is the naval force of Greece, part of the Hellenic Armed Forces. The modern Greek navy historically hails from the naval forces of vario ...
during 1925.
The Dart continued in service with the Blackburn Reserve School, alongside a number of T.3s converted to landplanes, until their eventual replacement by newer aircraft, the
Blackburn Ripon
The Blackburn T.5 Ripon was a carrier-based torpedo bomber and reconnaissance biplane designed and produced by the British aircraft manufacturer Blackburn Aircraft. It was the basis for both the license-produced Mitsubishi B2M and the improved ...
and
Blackburn Baffin
The Blackburn B-5 Baffin biplane torpedo bomber designed and produced by the British aircraft manufacturer Blackburn Aircraft. It was a development of the Ripon, the chief change being that a 545 hp (406 kW) Bristol Pegasus I.MS radial ...
, during 1933.
[Jackson 1968, pp. 153-154.]
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, successfully landing his Dart aboard ''Furious''.
The flight deck was illuminated by floodlights for the attempt but the docile Dart reportedly handled the task with ease. Within a few years, night time flights from aircraft carriers would become a routine operation.
[Jackson 1968, p. 153.]
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
![Blackburn Dart](https://upload.wikimedia.org/wikipedia/commons/5/51/Blackburn_Dart.jpg)
;
*
Japanese Navy
, abbreviated , also simply known as the Japanese Navy, is the maritime warfare branch of the Japan Self-Defense Forces, tasked with the naval defense of Japan. The JMSDF was formed following the dissolution of the Imperial Japanese Navy (IJN) ...
(as Swift Mk II)
;
*
Spanish Navy
The Spanish Navy or officially, the Armada, is the maritime branch of the Spanish Armed Forces and one of the oldest active naval forces in the world. The Spanish Navy was responsible for a number of major historic achievements in navigation, ...
(as Swift Mk II)
;
*
North Sea Aerial & General Transport Company (as T.3A Velos)
*
Royal Air Force
The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and ...
(
Fleet Air Arm
The Fleet Air Arm (FAA) is one of the five fighting arms of the Royal Navy and is responsible for the delivery of naval air power both from land and at sea. The Fleet Air Arm operates the F-35 Lightning II for maritime strike, the AW159 Wil ...
)
;
*
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
(as Swift F)
Specifications (Dart T.2)
See also
*
Sempill Mission
The Sempill Mission was a British naval aviation technical mission led by Captain William Forbes-Sempill. and sent to Japan in September 1921, with the objective of helping the Imperial Japanese Navy develop its aeronaval forces. The mission con ...
References
Citations
Bibliography
"The Blackburn Twin-Float Seaplane."''
Flight
Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can be a ...
'', 7 May 1925, pp. 269–272.
* Jackson, A.J. ''Blackburn Aircraft since 1909''. London: Putnam, 1968. .
* Mason, Francis K. ''The British Bomber since 1914''. London: Putnam, 1994. .
* Sturtivant, Ray. "Fleet Air Arm Colours 1923–33." ''Scale Aircraft Modelling'', Vol. 4, No. 6, March 1982.
* Taylor, Michael, J.H., ed. ''Jane's Encyclopedia of Aviation''. Danbury, Connecticut: Grolier Educational Corporation, 1980. .
* Woodman, Harry. "Blackburn Dart:The Fleet Air Arm's Seminal Torpedo Bomber". ''
Air Enthusiast
''Air Enthusiast'' was a British, bi-monthly, aviation magazine, published by the Key Publishing group. Initially begun in 1974 as ''Air Enthusiast Quarterly'', the magazine was conceived as a historical adjunct to '' Air International'' maga ...
'', No. 63, May–June 1996. pp. 2–11.
External links
The Royal Air force in the 1930s
{{USN torpedo aircraft
1920s British bomber aircraft
Dart
Dart or DART may refer to:
* Dart, the equipment in the game of darts
Arts, entertainment and media
* Dart (comics), an Image Comics superhero
* Dart, a character from ''G.I. Joe''
* Dart, a ''Thomas & Friends'' railway engine character
* Dar ...
Single-engined tractor aircraft
Biplanes