One day, many yeras ago, during a ferry flight of 140 nautical miles over the southPacific Ocean, alone in a single engine, I got to lighting the red "low-pressure engine oil". I drop the pitch down to going autorotation and light go off. . . . I check my gauges , everything was fine. I put the pitch up slowly up to 14 ° (14.5 ° cruise) the light stays off. I check again the oil pressure gauge and oil Temp : eveything is fine,
Oil pressure a little weak, but in the green arc.
I concluded that it is a sensor problem but without understanding the relationship with the pitch ....
I was 50 NM from the nearest land, so I continue my flight and climb a little be to keep some air under my ass . I continue and monitoring gauges.
10 minutes later, the light turns back on "LOW PRESSURE OIL" again I put pitch down slowly and at 13.5 ° light goes out .... I confirms the sensor failure but one more time i don't understand why ?
I ask for a short circuit and maintaining an angle of autorotation during most of the descent.
When i land, the mechanic came to me .I cut the turbine and she stop in few seconds ...
The mechanic ask me " Where is the engine oil ?"
After check of the turbine, it was An internal seal had gone in flight and I had burned all the oil through the turbine .....
In this case, i apply totally the manual about a LOW Pressure oil gauge failure ... And i am very lucky ... maybe few minutes or seconds more and the engine cut off in flight... Maybe no...