Low Rotor RPM Warning System - Fail

Flight #: 039
CFI: Kristie H.
Aircraft: Robinson R22 Beta II
Aircraft ID: N2356T
Duration: 0.8hrs
Cumulative Time: 42.8hrs

Again, we prepped for the stage 1 check flight. And, again we headed out to the WPA. On the way out, Kristie rolled down the throttle to check me on my Low RPM recovery... and I caught it. So that was good. We then went up to 1000ft MGL to do some autorotations. My entry was decent and I did a pitch pull. Was a little too much as the RPM dropped... to 90%. At this point the Low Rotor RPM light came on... but no horn. I corrected things and brought us to a decent steady state. Descended a bit further and rolled on and took us back to normal flight.

Problem. No Low Rotor RPM Horn. Part of our required equipment for an R22 is summed up with the GOAL acronym:

• G: Governor
• O: Outside Air Temperature
• A: Alternator
• L: Low RPM Warning System
  

And, without a fully functioning Low Rotor RPM system, we're not supposed to continue flight. So, I made the decision that we were not flying within the rules of flight and that we needed to head back home... which we did.

Kind of sucks to have to cut a short flight, but it's not worth falling out of the sky.