We are planning to do a test fire again this Saturday. We have made a number of changes. We have added very very fast butterfly valves just after the main (slow) ball valves. We hope this will have a bit more linear throttle action and be somewhat faster. Toward that end we have set up a flow test with an exact engine string, pressure transducer, ball valve, butterfly valve , pressure transducer,turbine flow meter , long tube and pintile orifice. We have started mapping how linear the valve is and it's flow response. This will all be on the test stand before Friday.
In addition I found some very small isolated thermocouples and we will instrument the fuel temperature rise for this event. So this weeks fireeing should generate some good data. I always planned to have the thermocouple, but the non-isolated version had some ground loop problems that totally swamped the signal I was trying to measure.
On the stability and control front I upgraded my helicopter from a Trex 450 to a Trex 600, it no longer wallows with the IMU, GPS and computer attached. We will report more on this effort next week.