Grounded by the Light

How the failure of a $42.50 part can result in $3,000 in lost revenue.

It was Friday morning and, for a change, I was running early. I had to pick up a passenger in Scottsdale for a day trip to the Grand Canyon. It would be my first Phoenix-area charter for the 2008/2009 winter season. I was due at Scottsdale Airport, about 40 air minutes away, at 9 AM; it was 7:40 AM.

The helicopter was on a west end helipad at Wickenburg Municipal Airport (E25). I started the engine, engaged the clutch, and brought the engine up to 55% RPM while the clutch belts grabbed at the upper sheave, turned the drive shaft, and began spinning the rotor blades. I started unfolding my Phoenix sectional chart to jot down the frequencies for the airports I’d be flying near or to.

That’s when I noticed that the Governor light was on. I looked at the governor switch on the end of the collective. The governor was turned on. But the illuminated light said it was turned off.

I toggled the switch. No change.

I pulled the circuit breaker, waited a moment, and then pushed it back in. No change.


I disengaged the clutch, let the rotor RPM wind down for the prerequisite 30 seconds, and pulled fuel mixture to shut down the engine.

About the R44 Governor

For those of you who don’t know what a helicopter governor is, here’s the short explanation.

When you fly a helicopter, you pull the collective lever up to increase the pitch of all rotor blades and climb. As you increase pitch, drag on the blades also increases. To keep the blades spinning at full RPM, you need to increase the throttle. The same is true, but in reverse, when you lower the collective to decrease pitch.

In the old days, the pilot had to coordinate the increase or decrease of collective with the increase or decrease in throttle as he flew. This greatly increases the pilot’s workload. Some modern helicopters still require this attention to the throttle. But most modern helicopters have what’s called a governor. This is an electronic device that automatically adjusts the throttle as needed to keep RPM in the green arc. On a Robinson helicopter, you can actually feel the governor at work sometimes as it twists the throttle while you’re holding its grip.

In the early days of Robinson helicopters, before there was a governor, a lot of pilots were getting themselves into deadly trouble by not keeping the RPM high enough for flight. Robinson introduced the governor and made it required for flight.

If you have a governor failure in flight, you can turn it off and manually adjust the throttle to maintain proper RPM. This happened to me once and it wasn’t a big deal. But, at the same time, if you have a governor failure before you take off, you can’t take off. It’s required for flight. (And yes, you can get a ferry permit to fly the helicopter to a mechanic, if necessary, to make the repair.)

So here I was, with a governor light on, telling me that the governor was not working properly. I was not able to fly until I resolved the problem.


Did you ever notice that a mechanical problem never manifests itself when a mechanic is around to observe it?

I fetched Ed, my Wickenburg mechanic, along with my parts manual. (Unfortunately, the maintenance manual was still up in Page.) Together, we went back to the helicopter to look at the situation.

I flicked on the master switch. The governor light remained off — as it should with the governor turned on.


We got the Robinson factory tech support guy on the phone. Ed spoke to him; it made no sense for me to be in the middle of the conversation. When he hung up, we went through the motions of checking to see if the governor was still functioning.

Ed removed the panel behind the front passenger seat where the governor is installed. Everything looked good. We raised and lowered the collective. Everything seemed to be running fine. Then I started up the engine while Ed watched the governor in action. I warmed up, then brought the RPMs up to 80%. The governor, as designed, began twisting the throttle to bring the RPMs up to the top of the green arc on the tachometer. The light remained off.

So the governor seemed to be functioning fine.

I shut down and Ed looked under the instrument panel where a relay that controlled the light was located. It looked fine — no loose wires, no signs of burning or melting. Everything looked perfectly functional.

Now I was in a quandary. The governor and its light were working fine, so I was legal to fly. But what if I got up to the Grand Canyon with my passenger and the light came on again? We’d be stuck up there. That would be a bad thing.

I decided to fly down to Scottsdale as planned. If I had no trouble on the way down there, I’d do the flight to the Grand Canyon. But if I had a problem on my way down or when I got down there, I’d cancel the flight.

The Best Laid Plans…

With the plan laid and everything buttoned back up, I prepared to leave again. An hour had passed; I’d called the client and warned him I’d be late, explaining exactly why. I climbed back into the helicopter, buckled up, and began my startup procedure.

The light came on as soon as I flicked the master switch. Of course, Ed wasn’t around to see it.


Now I knew I wasn’t going to fly to Scottsdale or the Grand Canyon that day. But I still needed an answer to one question: was the governor functioning even with the indicator light on?

I ran up the helicopter to 80% RPM. The governor took over and brought it smoothly to the top of the green arc. The governor was still working.

Troubleshooting and Doing the Math

At this point, I had a full summary of information for troubleshooting: The governor light was intermittently going on when it shouldn’t. The governor was working fine, even when the light was on. (Remember, light on is supposed to mean governor off.)

After shutting down and calling the client to cancel, I called Robinson’s tech support again and spoke to the same guy. I told him the symptoms. He said the only thing that could possibly cause the problem was a bad relay under the instrument panel.

I ordered a new one. It cost $42.50 plus shipping. Installation would be another hour or so at $75/hour, but would not happen until Monday at the earliest.

So I had to cancel my Grand Canyon charter that day and my appearance to do helicopter rides at Old Congress Days the following day. I also had to turn down a Phoenix Area tour on Sunday. In all, I figure I lost about $3,000 in revenue.

All for a failed $42.50 part.

The Rules

Now some of you might be saying, it’s not the governor that failed. It’s just the light. You should be able to fly.

Others might be suggesting that I just disconnect the damn light. (Three people in Wickenburg actually did suggest that.)

But I play by the rules. I’ve got too much time and money in my helicopter operations to risk losing my Part 135 certificate or pilot license for breaking the rules.

The rule I was worried about that day was my Part 135 requirements. Because I don’t have a minimum equipment list (MEL) I cannot legally fly my helicopter on any Part 135 flight with any part of the helicopter not functioning. A charter to the Grand Canyon would be a Part 135 flight. Clearly, a broken light would preclude me from flying that mission.

You could argue that I’d still be able to do the helicopter rides at Old Congress Days. After all, they were not Part 135 operations. They were part 91 (or 136). You could argue that the functionality of the light didn’t matter since the light is not required for flight. The governor is what’s required and it still worked fine.

I could agree, but I decided not to take the chance. Doing helicopter rides is not an easy job — especially at Congress’s confined space helipad. Flight after flight, I’m taking off and landing heavy, concentrating on clearing the short chain link fence and taller mesquite trees, keeping an eye out for trains (don’t ask), and dealing with the distractions of passengers. My work load is heavy enough without having to worry about whether the governor light can warn me about a governor failure. I decided it just wasn’t worth the risk.

I just don’t believe in taking unnecessary chances.

2 thoughts on “Grounded by the Light

  1. I wouldn’t want to be a passenger in a vehicle where the pilot couldn’t trust that crucial equipment was working because the indicator light wasn’t giving a true reading. I commend your scruples.

    The good thing is that the failed part was $40, not $400 or $4,000. :-)

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