I
first became aware of these engines when I was asked to go and borescope
them for someone who intended to purchase them as a lot from the
RAF.
Fortunately this gave me the heads up on the better engines amongst
them and enabled me to select the best one to purchase when the
original buyer decided against the idea. The
engine that I selected must have been the last enigne off of the
test bed, as the engine came with most of the test bed still attached.
These engines
were a modification of the standard 200 series Viper. Modifications
included a fuel system set up to permit greater fuel flow, the propelling
nozzle area was altered, and the govenor was adjusted to permit
a greater rotational speed. These (amongst other minor alterations)
enabled the engine to be operated at a significantly higher power
than the engine from which it was derived. This of course was at
the expense of a reduced TBOH.
These engines
were started by 120psi air impingement onto the turbine blade tips.
Please click the images to enlarge