UH-1H question
Maybe this should be in the mechanics forum but that mostly looks like fixed wing so Ill ask here. Have a UH-1H operated by a local sheriffs dept. When aircraft is powered(no engine or rotors turning) hear a weeep weeep weeep electrical tone coming thru the headsets. Which I assume is either engine out or low rotor rpm warning. This can be silenced with the rpm mute switch on the pedestal. Now when the aircraft is started and brought to idle or even 100 percent on the ground I get a different faster tone more like a woo woo woo woo woo coming thru the headset albiet faintly which can also be muted with the rpm mute switch. We thought the RPM Limit box was the problem and sent it out for troubleshooting. No problem found. came back and has same complaint after install. Does the UH-1H have a engine out tone that is different from the low rotor rpm horn? SHould I be hearing both tones when the aircraft is powered up but not running? The ARMY manuals we have arent of much help. We have now swapped N1 and N2 tach generators (same P/n) and are awaiting the pilots to return and run the aircraft (Monday) When aircraft is run all the gauges for N1, Rotor and turbine RPM are in the green operating range. Any help is appreciated. Ive been in the aircraft trying avionics off, pulling circuit breakers one at a time while aircraft was running to see if something might be bleeding over into the circuit causing a false signal triggering of this warning and no dice.