kerhs Posted November 3, 2003 Report Share Posted November 3, 2003 Can somebody give me the definitive answer as to what would happen in flight if you suffered a gen/battery problem, continued to fly and allowed the voltage to drop below the stated 22 Volts minimum. I have had a couple of suggestions (from engineers), 1) Nothing............ I doubt it!2) Governor would start to malfunction...........sounds feasible!3) Warning system would be inoperative.......also sounds feasible! Anybody help? :bowdown: Quote Link to comment Share on other sites More sharing options...
Wally Posted November 3, 2003 Report Share Posted November 3, 2003 1) Nothing............ I doubt it!Well, that's the best answer. The airframe will continue to fly and the engine should continue to make power. You'd want to treat it as a failed boost pump situation-descend, land ASAP or what ever is appropriate. You might have other issues- the oil cooler fan, for instance- but first thing is to fly the aircraft and not flame it out (boost pump).You'd still have a rotor tach and airspeed, altimeter, etc. 2) Governor would start to malfunction...........sounds feasible!Nope- The governor would operate normally. 3) Warning system would be inoperative.......also sounds feasible.Yep. No horn, no lights, no radio, no radar altimeter, BUT- no intercom either!- So you wouldn't have to listen to the passengers... Had this happen. Cascading failure, generator failure caution panel segment inop and I didn't catch it on preflight. Generator stopped genning and things got d-a-r-k Quote Link to comment Share on other sites More sharing options...
GLSNightPilot Posted November 5, 2003 Report Share Posted November 5, 2003 I don't know of any turbine engines in which loss of electrical power would result in any governor malfunction. The governors are mechanical, not electrical. With just low voltage, the warning system might or might not work. It's been many years since I flew an AS350, but I remember they had lots of electrical problems, and the design was just flaky. This was with the D model - the newer B2 & B3 models may be better. But loss of electrical power certainly isn't an emergency in itself - the engine will continue to work just fine with no electricity at all. Lack of kerosene is an entirely different matter. :crutches: Quote Link to comment Share on other sites More sharing options...
as 350 Posted November 5, 2003 Report Share Posted November 5, 2003 One thing that has not been mentioned so far: as you lose battery, your NR gauge (rotor rpm) will start to give you inaccurate readings as well.Rotor rpm indication is obtained by an indicator (gauge) energized by a magnetic sensor (sending unit on top of mgb transmission) located in front of a slotted wheel driven by the rotor and sensing the rotor rpm. As the rotor turns, it creates a magnetic flux, which in turn induces an electric pulse (signal) to the back of the gauge.The gauge is nothing more than a "frequency-voltage" converter, which transforms the electric pulse into D.C. signals. For that to happen accurately, though, you need a base current off the ship electric bus (the PP5 bus bar).After a generator failure and subsequent low bat, the gauge is not receiving its required 28 volts off the battery and therefore the rotor rpm will be inaccurate.Long story short: if you encounter a low bat and gen failure, expect your rotor rpm gauge to not work properly.That is reason enough for me to be on the ground calling my DOM long before the battery is low. Quote Link to comment Share on other sites More sharing options...
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