Blackburn

Blackburd

The Blackburn Blackburd was a single engine torpedo bomber designed by Harris Booth against Specification N.1B to carry the heavyweight (1,423 lb) Mk VIII torpedo and was intended as a replacement for the Sopwith Cuckoo.

 

In the event, the end of the First World War intervened and only three prototypes were ever built.

 

Designed for rapid, low cost, production, the Blackburd was a three-bay biplane with rectangular wing planform with a fuselage similarly rectangular in its side elevation.

 

As a result it is by some margin one of the least attractive Blackburn aircraft in terms of its appearance. No doubt, as Charles E Grey (editor of The Aeroplane magazine) once remarked about another type, it could be described as “undoubtedly built for use and not for ornament.”

 

Similarly, the main planes could have received the same description as he gave to those of the De Havilland DH6 trainer, as being “made by the mile and cut off by the yard”.

 

 

Power was provided by 350 hp Rolls-Royce Eagle engine driving a two-blade tractor propeller and to aid slow speed operation, all four wings carried ailerons that could also be lowered to act as flaps to reduce take-off and landing speeds.

 

The undercarriage was provided with steel skids (or skis) inside the wheels, which were carried on a transverse axle. This arrangement meant that the undercarriage (axle and wheels) had to be jettisoned before the torpedo could be dropped and the carrier deck landing being made on the steel skids.

 

 

The first prototype (N113) was completed in late May 1918 and was flown for the first time before the end of the month. Initial constructor’s trial included trials of the undercarriage and torpedo dropping mechanisms over the River Humber.

 

The prototype was flown to Martlesham Heath for evaluation trials on 4th June 1918 where official testing found that the use of the ailerons as flaps unacceptably reduced their effectiveness on take-off. The aircraft was also found to be nose-heavy, whether or not the torpedo was being carried. The rather small rudder was also criticised for lack of effectiveness. An accident in early July brought these initial trials to an end.

 

The second prototype (N114) had small floats fitted beneath the lower wingtips although following the results of the prototype testing, this aircraft was fitted with a larger rudder, having a rounded trailing edge. The tailplane was also stiffened when the company considered that its deflection under load had contributed to the nose heavy flight that was encountered with the prototype.

 

It carried out torpedo trials at East Fortune in September 1918 and was delivered to Martlesham Heath on 16th October 1918. Official trials continued into November 1918 including full performance measurements, with and without torpedo carriage.

 

The third prototype (N115) was delivered to the Fleet Air Arm Development Squadron at Gosport in November 1918 and it continued in use at least until mid-1919.

 

This aircraft was later briefly converted to a two-seat configuration.