Snow That Goes Bump in the Night

by Michael Lenz
Reprinted with permission from FAA Aviation News

Bill was a meticulous young doctor. He did every thing full out. He tied for the top spot in his medical school class. At 30, he was beginning his practice and held a private pilot certificate with instrument rating and had a total time of 360 hours. Thirteen of those hours were in the Mooney M20C involved in this accident.

Unbeknownst to Bill, the rental plane had altimeter problems. After the accident, it was learned that the barometric adjustment gears for the Kollsman setting did not mesh and this allowed the altimeter's hands to move while the barometric scale did not.

On an April day back in the1970's, Bill was pilot-in command on a mission to fly from Milwaukee to Wyoming to look at a campground that he and his three passengers were considering as an investment. The other travelers were Joe, Fred, and Susie. Joe, also a doctor and private pilot, was in the right seat. Fred and Susie, a husband and wife, were in the rear seats.

Dr. Joseph 'Joe' Hoffman tells it best:

The flight was going well. We had stopped for fuel in Sioux City, Iowa, and the weather was good. We took off and continued westbound.

I recalled, as night fell on the accident leg of the flight, we were over Nebraska as we began to run into un-forecasted snow. It persisted and became heavy. We were on a VFR flight plan and called ATC to see about finding a route clear of the snow. They said they weren't showing anything and couldn't suggest any alternate routing. [Remember this was 1970'stechnology.]

Bill changed our flight plan to IFR figuring the snow would end soon. It didn't! It was late now and the snow began sticking to the wings and was so heavy that all we could see was a faint glow from the wingtip lights. We requested clearance to Scott's Bluff, Nebraska, where we could sort things out and get a better handle on the weather.

The faulty altimeter was showing us at 5,000 feet, but in reality we were much lower and narrowly missing treetops. Bill had his hands full flying instruments. Visibility was almost nil, at the last minute I saw the terrain and bluff approaching and pulled back on the stick, but it wasn't enough, and we impacted into the fresh snow. A few feet either up or down, and I probably wouldn't be writing about this now.

I lost eight teeth and suffered facial injuries that required plastic surgery to correct. After the impact, Bill, seriously injured and in a state of shock, continued to fly the plane. Fred and Susie had minor injuries. Bill didn't believe we had crashed. I said I'm going for help. He said,' You're crazy, don't open that door, we're at 5,000 feet!' I had a hunch we weren't.

I stepped out of the plane into snow up to my chest. Fred and Susie followed. A bit dazed, I didn't bother to take my coat. The only thing I could see was a light that, fortunately, was downhill from the crash site. I hate to be cold, and to me that light meant it must have be warm nearby and I was going for it.

The light turned out to be about three and a half miles away. It took around two hours to reach it. Fortunately it had stopped snowing now. The snow may have been an 'on-again, off-again' thing and that's why ATC wasn't showing it.

The light was from the only farm around, and we knocked on the door of the house. The farmer's wife answered about midnight. You can only imagine the sight that greeted her'the three of us wet and cold and me a bloody mess. She wouldn't let us in -side because her husband was out tending to the cows.

When the farmer returned, they happily let us in and I proceeded to bleed all over the furniture until help arrived. We were taken to the hospital and a separate group of emergency personnel went to rescue Bill.

Bill had serious chest injuries and was MedEvac'd to a hospital in Houston. He survived and practices medicine today. We still talk, although in -frequently. We did joke later about Bill's rescue. He was still flying the plane when the emergency personnel arrived. He later told me it was quite a shock to him when 'in the middle of the flight' the rescuers opened the door and people were getting in the plane! He said he thought he must have died and that they were from heaven. I told him in his case, they might not have been from heaven. But that's another story.

In retrospect, it's ironic that the snow that almost killed us may have also saved our lives. The reason the light was on that lead us to the farm -house was because the snow was so high, the farmer had to make sure the cows could not walk up and over the snow and cross the fences. The farmer said our guiding light, which illuminated the whole area surrounding the barn, was only on four or five times a year.

The 'driven snow' that night also drove me out of aviation. I stopped flying after that. I learned how suddenly snow could start, even in late April. If weather as severe as the sudden snowstorm that brought us down that night was unforecast and could not be detected by ATC, I thought the risks were too great to use general aviation aircraft for transportation.

That was over 30 years ago, and fortunately a lot has changed for the better regarding weather forecasts and detection. I have taken a few more flying lessons since then in California where I live, but never stuck with it and got serious about getting back into aviation. And, by the way, I did buy the farm couple some new furniture to replace the blooded pieces.

This is an intriguing story of rescue and a narrow escape from what could have easily been a fatal accident. Equally important is the lesson of how unpredictable and transient snow can be.

In the time that has passed since this accident, aviation has benefited from improvements in forecasting and weather reporting. Now we have numerous ATIS/AWOS/ASOS locations available to monitor conditions at terminals along our route of flight. En-route Flight Advisory Service (Flight Watch, 122.0 MHz) has also been enhanced.

Keep in mind that this accident predated GPS navigation. GPS now allows us precise VFR flight at altitudes that previously would have been below the altitudes of VOR coverage. Almost all GPS navigators include a feature that can be used in Terrain Avoidance Planning or TAP. Since GPS knows where it is, it also knows the minimum safe altitude for the area and can be used in VFR flight planning.

Terrain Avoidance Planning can be used when any precipitation is forecaster if marginal weather (ceiling below 3,000 feet and/or visibility below five miles) or close temperature dew points are forecast anywhere along the proposed route. It's forecasts that include these types of conditions that can lead to big surprises in-flight. This is especially true when reporting stations along the route maybe good VFR at the time of the preflight weather briefing, but changes are in the offing.

When it comes to weather 'What you see, is what you get.' That maybe most true in winter when weather systems, fronts and lows, really get a push from the atmosphere. If the weather you see out the window is not the same as the forecast, it's time to proceed with great caution. It may even be time to consider some alternates. You did include some contingencies in your flight planning, right?

Update your weather information from Flight Watch or ATC. Tune in Hazardous In-flight Weather Advisory Service (HIWAS - broadcast on select VOR frequencies), or ATIS, AWOS/ASOS to keep up with what's happening and learn what nearby terminals are reporting.

Enjoy the winter wonderland, instead of one winter day wondering where you're going to land.

Michael Lenz is a Program Analyst in Flight Standards' General Aviation and Commercial Division