Blackburn B-20

Infobox Aircraft
name=Blackburn B-20


caption=The B-20 afloat. Note the notch in the lower fuselage where the main float retracted. A notch can also be seen in the end of the wing, where the support for the wing float lay when it folded outward.
type=
manufacturer=Blackburn Aircraft
designer=J. D. Rennie
first flight=March 1940
introduced=n/a
retired=
status=Cancelled
primary user=
more users=
produced=
number built=1
unit cost=
variants with their own articles=The Blackburn B-20 was an experimental aircraft, first flying in 1940, that attempted to drastically increase the performance of flying boat designs. Blackburn Aircraft undertook an independent design study based on a patent filed by their chief designer, J. D. Rennie.ref Jane's|Blackburn B.20|107]

The B-20 was an attempt to combine the best features of both the flying boat and the floatplane. While on the water, the B-20 was essentially a floatplane, using a large float under the fuselage for buoyancy, and two smaller floats near the wing tips for stability. In flight, the main float retracted towards the fuselage, fitting into a "notch" to become streamlined as a part of the fuselage. The wing floats folded outward to become the wing tips.cite web|last=Dell|first=John|work=Dinger's Aviation Pages|accessdate=2006-08-19|url=http://freespace.virgin.net/john.dell/blackburn_b20.htm|title=Blackburn B20]

Blackburn along with Supermarine and Saunders-Roe tendered craft for Air Ministry Specification R1/36. What would enter service as the Saunders Roe Lerwick was the chosen aircraft but the Ministry was interested enough to authorise two prototypes of the B-20. The prototype would fly for the first time in March 1940. On the 7 April during a test run the aircraft experienced extreme vibration due to aileron flutter and the crew bailed out, three were lost the other two were picked up by HMS "Transylvania", a converted merchantman. Development ceased when the first prototype crashed, as Blackburn's resources were dedicated to the war effort.

pecifications (B-20, as designed)

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

ref=Jane's Fighting Aircraft of World War II
crew=6
span main=82 ft
span alt=25 m tip-floats retracted
length main=69 ft 8 in
length alt=21.2 m
height main=25 ft 2 in
height alt=7.65 m
area main=1,066 ft²
area alt=99 m²
empty weight main=
empty weight alt=
max takeoff weight main=35,000 lb
max takeoff weight alt=16,000 kg

engine (prop)=Rolls-Royce Vulture
type of prop=24-cylinder X-type engines
number of props=2
power main=1,720 hp
power alt=1,280 kW

max speed main=306 mph
max speed alt=266 knots, 490 km/h
max speed more=at 15,000 ft (4,600 m)
loading main=
loading alt=
ceiling main=
ceiling alt=
climb rate main=
climb rate alt=
range main=1,500 mi
range alt=810 nm, 2,400 km
power/mass main=
power/mass alt=

guns=provision for two turrets and other defensive positions
bombs=bomb-cells in centre section

References

*

ee also

aircontent

sequence=
* B-20 - B-37 - B-44 - B-48

related=

similar aircraft=
* F2Y Sea Dart
* Saro Lerwick

lists=
* List of experimental aircraft
* List of aircraft of the RAF

see also=