This is the test day with the owners present, of a Roll Royce Avon at S&S Turbines outdoor test cell.
Unlike the last Avon, this has had the starter drive modified to accept an air turbine starter. It's the starter freewheling you see near the end.
Max RPM for this engine is about 7900 rpm, and idle is at 3500. We give it fuel at around 1200 rpm, but it still needs the starter to help it approach idle.
This engine is used as a power source for a gas compression facility. The exhaust gases are used to turn a power tubine, which is connected to a natural gas compressor, which moves large amounts of natural gas through a pipeline.
Power output is close to 20,000 Hp.
