Blackburn Cubaroo

infobox Aircraft
name = T.4 Cubaroo
type = Torpedo Bomber
manufacturer = Blackburn Aircraft


caption =
designer = F A Bumpus
first flight = 1924
status = Prototype
primary user =
more users =
produced =
number built = 2
unit cost =
developed from =
variants with their own articles = The Blackburn T.4 Cubaroo was a prototype British biplane torpedo bomber of the 1920s. Built by Blackburn Aircraft and intended to carry a large 21 inch torpedo, the Cubaroo was one of the largest single-engined aircraft of the world at the time of its first flight.

Design and development

In 1922, the British Air Ministry drew up Specification 16/22, for a long-range torpedo bomber capable of carrying a 21 inch torpedo (which was at the time thought capable of sinking the largest warship) over a range of 800 miles (1,300 km) Cite book |author=Mason, Francis K |authorlink =
|title=The British Bomber since 1914 |publisher=Putnam Aeronautical Books |location= London |year=1994 |isbn= 0 85177 861 5. Major F. A Bumpus, chief designer of Blackburn Aircraft submitted the design for the Blackburn T.4 Cubaroo, which was a large biplane powered by a single example of the new 1,000 hp (746 kW) Napier Cub engine. Avro also submitted a design against this specification, the Avro 557 Ava, which was a similarly large biplane, powered by two 600 hp (448 kW) Rolls-Royce Condor engines. In order to carry the heavy (over 2000 lb (909 kg)) torpedo over a long range, the Cubaroo was massive. With a wingspan of 88 ft (27 m), it may have been the largest single-engined military aircraft in the world at the time, and was fitted with the most powerful aircraft engine available cite book |title=The British Bomber since 1914 |last=Lewis |first=Peter |edition= Third Edition |date= |year=1980 |publisher=Putnam |location= London |isbn= 0 370 30265 6] , the Napier Cub, which was an unusual X-type engine which weighed over a ton excluding radiators. The Cubaroo, with a mainly metal structure, had a deep fuselage to accommodate the Cub engine, and was fitted with folding, two-bay wings. In order to allow the torpedo to be carried, the Cubaroo was fitted with a main undercarriage comprising two sets of two wheels, with the torpedo being carried on a crutch between the two sets of wheels.

Operational history

The first prototype (with serial "N166") flew in secrecy in the summer of 1924, proving to have good handling characteristics, with the engine not causing problems (the Cub had already been test flown in an Avro Aldershot test bed) . It was then fitted with a metal, three-blade adjustable pitch propeller and was delivered for testing at RAF Martlesham Heath, but was written off after its undercarriage collapsed on 2 February 1925. A second prototype flew in 1925, but the Air Ministry abandoned the requirement for a torpedo bomber to carry the 21 inch torpedo, and lost interest in single engined heavy bombers, so the second prototype Cubaroo was used as an engine test bed, flying with the experimental 1,100 hp (820 kW) Beardmore Simoon engine .

Operators

;UK
*Royal Air Force operated aircraft for evaluation and as a test bed only.

pecifications (Cubaroo)

aircraft specifications
plane or copter?=plane
jet or prop?=prop

ref=The British Bomber since 1914

crew=Four - Pilot, Navigator, Bomb-aimer/gunner and midships gunner
capacity=
length main= 54 ft 0 in
length alt= 16.46 m
span main= 88 ft 0 in
span alt= 26.83 m
height main= 19 ft 4 in
height alt= 5.89 m
area main=
area alt=
airfoil=
empty weight main= 9,632 lb
empty weight alt= 4,378 kg
loaded weight main=
loaded weight alt=
useful load main=
useful load alt=
max takeoff weight main= 19,020 lb
max takeoff weight alt= 8,645 kg
more general=

engine (prop)=Napier Cub
type of prop=16 cylinder water cooled X-type engine
number of props=1
power main= 1,000 hp
power alt= 746 kW
power original=
max speed main= 100 knots
max speed alt= 115 mph, 185 km/h
cruise speed main=
cruise speed alt=
never exceed speed main=
never exceed speed alt=
stall speed main=
stall speed alt=
range main= 1,565 nm
range alt= 1,800 mi, 2,900 km
ceiling main= 11,800ft
ceiling alt= 3,600 m
ceiling more= (absolute)

loading main=
loading alt=
thrust/weight=
power/mass main=
power/mass alt=
more performance=

armament=
* Three .303 in Lewis guns in midship gunners cockpit and at beam hatches
* One 21 inch (533 mm) naval torpedo "or"
* Four 550 lb (250 kg) bombs
avionics=

ee also

aircontent

related=

similar aircraft=*Avro 557 Ava

sequence=

lists=

see also=

References

External links

[http://www.britishaircraft.co.uk/aircraftpage.php?ID=594 British Aircraft Directory]