Blackburn RT1 
Kangaroo

Landplane version of the Blackburn GP seaplane used for commercial operations in the 1920s.
Blackburn RT1 Kangaroo prototype B9970 The prototype Blackburn RT1 Kangaroo with unsprung undercarriage.
 
The Blackburn RT1 Kangaroo was a landplane version of the Blackburn GP (General Purpose) seaplane although without the large float undercarriage the Kangaroo offered long range and a significant weapon load.
 
The Kangaroo had been intended for use on maritime reconnaissance and torpedo operations, operating from land bases. In practice however, it was used as a conventional bomber carrying four 230 lb bombs or a single 520 lb bomb. These were carried internally and were supplemented by four smaller anti-submarine bombs mounted externally beneath the fuselage.
 
The type was distinguished by its slim fuselage and by the unusually large overhang of the upper wings.
 
Power was provided by two 250 hp Rolls-Royce Falcon II engines, driving four-blade wooden propellers.
A four-wheel undercarriage was provided and which was divided into twin-wheel pairs, with cross axles, all fitted beneath each engine.
 
The first prototype (B9970) had an unsprung undercarriage whilst later aircraft were fitted with wider, shock-absorbing main undercarriage legs.  
 
Blackburn RT1 Kangaroo prodn undercarriage An unidentified Blackburn Kangaroo with the production standard sprung undercarriage.
 
Accommodation for a bomb-aimer and forward gunner was provided with an exposed cockpit in the extreme nose which was ahead of the separate open cockpit for the pilot. The rear gunner (who also served as wireless operator) was seated in a third cockpit aft of the wings.
 
The prototype was flown for the first time in late December 1917 and was subsequently delivered for trials at Martlesham Heath on 3rd January 1918. Unfortunately these trials were not entirely satisfactory with the fuselage being criticised for weak torsional stiffness and the unsprung undercarriage failing on the notoriously rough surface at Martlesham. These failings were addressed however in the production aircraft. The final 15 production aircraft all received 270 hp Rolls-Royce Falcon III engines.
 
The prototype and all nineteen production aircraft were purchased by The Admiralty and these ultimately delivered to the RAF with serial numbers ranging from B9970 to B9989. They were delivered to RAF Seaton Carew where they were used for long endurance anti-submarine patrols and famously on 28th August 1918, submarine UC70 was crippled by a bomb dropped from Kangaroo B9983 and was subsequently sunk by depth charges.
 
After the War, eleven Blackburn Kangaroo aircraft appeared on the civil register, three of these (G-EADE – G-EADG) being used by the Grahame-White Aviation Co Ltd for joy-riding, featuring a pair of enlarged rear cockpits to accommodate a total of seven passengers, with an eighth occupying the cockpit in the extreme nose.
 
In April 1919, Blackburn set up the commercial aviation subsidiary The North Sea Aerial Navigation Co (later renamed The North Sea Aerial and General Transport Co Ltd). Eight surplus Kangaroo aircraft were purchased and the first (G-EAIT) was modified to carry seven passengers in an enclosed cabin before entering service from 10th May 1919.
 
Three Kangaroos took part in an Air Traffic Exhibition (ELTA) in Amsterdam in August 1919, carrying between them some 1,400 fare-paying passengers.
 
The original prototype (BB970) was earmarked for an attempt to make the first flight between England and Australia and received the civil registration G-EAOW. The aircraft left Hounslow on 21st November 1919, just nine days after the successful Vickers Vimy, flown by Ross and Keith Smith.
 
Blackburn RT1 Kangaroo G-EAOW Suda Bay 8_12_1919 The England - Australia Kangaroo G-EAOW after its mishap at Suda Bay, Crete.
 
Unfortunately bad weather caused delays and the flight came to a halt at Suda Bay, Crete on 8th December. A fractured (possibly sabotaged) oil feed pipe caused an engine failure, resulting in a single-engine return to the airfield and a downwind landing. As if things weren't difficult enough a burst tyre resulted in the aircraft swinging off the runway and ending nose down in a ditch. Although substantially undamaged, the aircraft and the flight attempt were both abandoned.
 
The final role for the Kangaroo was as a training aircraft and in 1925 a Reserve Flying School was set up at Brough, managed by The North Sea Aerial and General Transport Co Ltd. Four Kangaroos were modified and fitted with dual control cockpits to provide twin engine refresher training to RAF Reserve pilots.
 
The first (G-EAIT) crashed on 5th May 1925 shortly after its conversion. The remaining aircraft (G-EBMD, G-EBOM and G-EBPK) were converted after the crash and they were named (after cartoon characters) as Wilfred, Pip and Squeak.
 
Blackburn RT1 Kangaroo dual control G-EBOM Dual-control trainer Kangaroo of the RAF Reserve School at Brough in 1926.
 
Finally, G-EBOM crashed after engine failure on 29th May 1928 and the two surviving aircraft were scrapped in 1929 following expiry of their Certificates of Airworthiness.
 

Variants & Numbers Built

 

Prototype
One aircraft B9970, later G-EAOW
Kangaroo production
19 production aircraft B9971 to B9989
Total built
20 aircraft – one prototype and 19 production aircraft.

Specification (RAF aircraft with Rolls-Royce Falcon II)

Powerplant
Two 250 hp Rolls-Royce Falcon II
Span
74 ft 10.25 in
Maximum Weight
8,017 lb (with 920 lb bomb load)
Capacity & Armament
Three crew; two defensive Lewis guns, four 230 lb bombs or one 520 lb bomb carried internally.
Maximum Speed
100 mph at sea level; 86 mph at 10,000 ft
Endurance
Up to eight hours

Survivors

No Blackburn RT1 Kangaroo aircraft survive.