In the summer of 2009 I was flying a Schweizer 300CBi helicopter on a solo cross-country flight over the beautiful Flathead Valley of northwestern Montana. This valley is especially picturesque with the unforgiving Rocky Mountains forming an ominous barrier along Flathead Lake’s east side. On the valley floor is the serpentine Flat Head River, which empties into the very large lake, in turn surrounded by lush farmlands with small mountains bordering on the west. My route was to circumnavigate the lake, a trip of about 92 miles—a pretty short distance by airplane standards, but a good distance for a helicopter. Starting from Kalispell’s City Airport, I planned to fly south along the western edge of the lake to Polson Airport, then on to Ronan Airport, and back north up the east side of the lake.
The Schweizer cruises at 75 to 80 knots, and I was expecting light winds and clear skies for the 90-minute flight. I was on about my thirtieth hour of private training. The southbound leg and the landings at Polson and Ronan were good, and my confidence was starting to soar.
Heading north along the lake with the Rocky Mountains dwarfing the helicopter was spectacular. Flying at 800 feet over the lake edge put me 4,000 feet below the mountain tops. I was enjoying the view and beginning to relax a bit.
Suddenly, the engine misfired. All tranquility ceased. In a helicopter when a misfire or engine roughness occurs, the pulse propagates through the drive train to the rotor blades and tail rotor blades, becoming greatly amplified. It shakes the whole aircraft for a very long one to two seconds. I immediately checked the gauges: Rotor rpm, OK; engine rpm, OK. A quick scan of the oil temps and pressures revealed no anomalies. A thousand things went through my mind all at once as a wave of panic started to build. I remembered my instructor’s words: “If something ever happens, fly the ship. Keep flying and deal with things one at a time. Fly the ship!"
I realized the shuddering had stopped. My first thought was that I had had a bird strike or that something was coming apart. I began to look for bird parts hanging from the helicopter (you can see almost every part of the ship from the cockpit). No body parts.
Back to the gauges—all in the green. What had happened?
The engine smoothed out and I decided to simply fly straight and level for a while and keep my flight path over beaches and roads. After a few minutes my pulse returned to normal and I decided to try a slight, smooth climb. After all, I was going to have to make considerable power changes on landing in the next 15 minutes and thought it better to have some altitude to experiment. I made a beeline back to the airport and performed the softest approach and landing that I could muster.
After shutdown and a shaky walk into the hangar I reported to the mechanic, who instantly grounded the aircraft and began an inspection. It was found that a failing magneto had caused the helicopter to shudder so violently. This is what I learned: First, it is OK to enjoy the view, but don’t be complacent. I now scan the gauges every few minutes and before any attitude changes or maneuvers. I don’t ever want to be caught with having to answer, “I don’t really know" to an investigator’s questions about the status of the aircraft systems after an emergency.
Second, in the event of an emergency or anomaly, fly the ship.
Third, know your aircraft. Know the systems; know the normal sounds. Know the autorotation distance and capabilities of the helicopter and practice hitting the mark during autorotation practice.
Fourth, be smart about terrain. Helicopters fly low and slow. Always be looking for landing contingencies and ask yourself, “Do I have to fly over that?”
Finally, make sure that there are survival supplies and a first aid kit on board. Ask yourself: If an emergency occurs, how long do I want to be waiting for rescue without a coat?
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