Anti-turbo lag systems

[William A Williams]

	This whole line of GT development dates back to the 50's when
there were some gas turbine starters developed for ground use in very
cold climates. They were simply small gas turbines that burned enough
fuel to put out a hot, pressurized exhaust that was ducted to the engine
that you wanted to start. The hot gasses flowed through the engine,
spooling it up, warming it up, and leaving sufficient oxygen in the
exhaust to support combustion in the engine being started. They were
really small and light units and when they came on the surplus market
there was a flurry of interest in them as potential conversions for
homebuilt aircraft. Sadly it was found that they didn't have good enough
metallurgy in the turbine wheel to make a decent power. This concept of a
bypass of air/fuel for turbo spinup was discussed in the 60's with
respect to the Corvair turbo setup as a cure for a high rotational
inertia in it's turbo. Of course with the carburetted mixture it was
rather simpler, requiring only a pressure driven shutoff and some
pneumatic control logic.
             Bill in Boulder     ----  "Engineering as an Art Form" ----