LIMPING ALONG.

PARTIAL-POWER-LOSS PROBLEMS.

On a Friday morning in August, my wife, my dog, and I took off from Princeton, New Jersey, in my Cessna 172M. We were headed 50 minutes north to Cherry Ridge Airport in Honesdale, Pennsylvania, from which we would have a short drive to our vacation home in the Poconos. I added a quart of oil; did a thorough preflight, found nothing out of the ordinary; and runup was normal. We took off, requested flight following from New York Approach, and looked forward to the weekend.

About two-thirds of the way to our destination, the engine sound suddenly changed. The steady rumble became intermittent, sounding perhaps like one cylinder had stopped firing. There was also significant vibration.

I had been handed off to Wilkes Barre Approach, and I told the controller I had a situation and described it, asking for the nearest airport. He told me about Flying Dollar (8N4), 6.5 miles to my west, and a couple of others further away. I was aware that this stretch of my trip to the Poconos offered no good options; the entire area below was forested hills. I had never heard of 8N4, which was a grass strip—a surface I had never used before.

I set the mixture control to full rich, pulled the carb heat, and verified that the primer was locked; all the gauges and settings seemed to be right. I even did a mag check, and both sides maintained the irregular engine performance. Upon arrival at the magenta spot on the GPS, I saw no windsock or parked airplanes. But there was a long, narrow green strip.

I was still quite high, maybe 2,000 feet agl. I normally plan the descent from about 10 minutes out so I efficiently lose about 500 feet per minute, and arrive at pattern altitude at just the right time. In this tense situation, however, I did not want to give up altitude any faster than necessary, so I was much higher than usual.

I executed a forward slip and dropped as fast as I could while keeping control of the airplane. I did not extend flaps. As I arrived at Flying Dollar’s Runway 20 and flared, the airplane bounced dramatically.

I bounced perhaps three times, applied some of the power I had, and the airplane began to settle down onto the runway just as it should—but I was running out of runway: The terrain dropped off pretty significantly beyond the runway’s end.

(The airport owner later told me that because of the slope, the locals land on 2 and take off from 20—I had unknowingly tried to land on the down slope.)

I decided to attempt a go-around with what power I had. It worked, after a fashion; I gained some altitude and held it. I flew a 180-degree turn at 20 to 40 feet agl, much of which was contributed by dropping terrain rather than by climbing airplane. I finally was on approach to Runway 2, but I was below the runway’s elevated end! I watched the airspeed fall to around 40 mph, heard the stall buzzer, watched the ground approach, and “landed” all at one time.

Since the terrain was rising more steeply than my critical angle of attack, it was impossible to land parallel to the ground without first stalling. The nose-wheel and left main hit the ground first, breaking off, and the airplane nosed over.

Thanks to our seatbelts and the dog’s harness that strapped into the back seatbelt, we suffered no major injuries. The doors opened fine, and I had never shut off the fuel valves because I was still using some power up to the end. But there was no fire or any other complication.

The FAA found that cylinder four had no compression and two of the other three cylinders had low compression. Presumably, a valve had stuck. The logbooks from the most recent annual, just two months prior, were in order.

While I had practiced “engine out” a lot, I was off-balance when faced with partial power. The intense vibration of the engine also was unsettling; I still don’t know if my concern about the engine shaking off the mounts was realistic or absurd, but it caused me to rush.

I’d considered proceeding to a known airport, as I did have partial power, but decided to get on the ground as soon as possible. I don’t regret that decision.

I was so focused on best glide speed and keeping as much altitude as possible that I was unprepared to deal with the fast descent needed to get to the field.

I used a forward slip, which is the only technique I recall from training, but I believe more relaxed circles might have served me better.

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