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Never Again Online: The right number of mistakesNever Again Online: The right number of mistakes

Airmet Zulu: moderate rime and mixed icing in clouds and precipitation between freezing level and Flight Level 200. Any pilot in the Pacific Northwest is familiar with this statement.

Airmet Zulu: moderate rime and mixed icing in clouds and precipitation between freezing level and Flight Level 200.

Any pilot in the Pacific Northwest is familiar with this statement. In fact, I have received that airmet so often, and on the same day provided flight watch with my pirep of negative ice on the climbout and VFR on top, that I began thinking of the fable about the little boy who cried wolf — my first mistake.

Most private pilots have pocket books that limit us to flying airplanes whose operating handbooks contain the statement, "Not approved for flight into known icing conditions." If every airmet came true, none of us "nonicers" would take off into instrument meteorological conditions (IMC) all winter long. But sometimes we do it anyway.

On a winter day I embark on a trip from my home base, Mirth Airport, a private turf strip in Hansville, Washington, about 50 miles southeast of Seattle, to Castlegar, British Columbia, Canada. My filed route is direct to McChord Air Force Base, Victor 187 to Ellensburg, direct to Castlegar at 11,000 feet.

I check weather and it's the usual for coastal Washington — marginal VFR at departure, cloud layers to Flight Level 200, and an icing airmet over the Cascade mountain range with VFR conditions from Ellensburg, at the eastern edge of the Cascades, to my destination. Winds aloft are out of the west at 30-plus knots. Great, I can get there really fast, just like if I had a Mooney instead of a Cessna 182! At 5:30 that morning, after I download the DUATS weather information while waking up, I skim over the part about the warm, unstable air mass approaching the coast — my third mistake. The freezing level is 7,000 to 8,000 feet. Having made early morning departures across the Cascades numerous times before, I am well aware that pireps don't start coming in until 7:30 or 8:30 a.m. when normal people launch. So I'm not surprised at the lack of firsthand information on the actual conditions over the Cascades at my 6 a.m. departure — my fourth mistake.

Instrument pilots are taught about ice. We know that the secret is to climb high enough to get above the ice (where an outside air temperature is minus 15 degrees Celsius or less), or stay above or between layers of clouds, and you are home free. I take off and head up to my assigned 11,000-foot altitude. I am enjoying the climb power of a lightly loaded 182. I break through the cloud tops at 9,500 and cruise at 11,000 more than 40 miles from what is locally known as "the ice machine" on the western slopes of the Cascades. The combined candlepower of Seattle's lights makes a pretty amber glow through the clouds on my left. We are trimmed, level, on course, VFR on top, with everything in the green and no ice on climbout. I figure I'm home free — my fifth mistake.

About this time approach calls and amends my clearance. I'm given a heading and told to join Victor 2 and resume my own navigation. V2 is a straight shot east, just north of Mount Rainier, from Seattle-Tacoma International Airport to Ellensburg.

Victor 2 has a minimum en route altitude (MEA) of 8,000 feet. MEAs were a mystery to me when I was a VFR pilot. Someone decided that if you are IFR over mountainous terrain, the lowest you should go is 2,000 feet above the tallest thing close to your course. I used to think this was excessive since the standards for IFR are also to hold altitude plus or minus 100 feet — my sixth mistake. On this day, I would find out it's a damn good rule.

After copying the amended route I reprogram my IFR-legal GPS and tune in the Seattle VOR. About the time I join the airway, the clear darkness turns to hazy darkness. I am in the clouds. My groundspeed is 160 kt and the miles to Ellensburg are clicking down smartly.

I am concerned about ice upon entering the clouds. After all, I know that the western slopes of the Cascades provide a unique geographical instigator for the ice machine. Moist, westerly onshore flow from the Pacific Ocean and orographic lifting caused by terrain rising from sea level to 8,000 to 14,000 feet produces the mother of all icing. The icing is so profound that most aircraft manufacturers come to Seattle so they can test their wares in the extreme conditions.

My flashlight illuminates a trace of rime on the left wheelpant and wing. I don't remember to check the outside air temperature gauge — my seventh mistake. I continue to check the ice on the wheelpants and wing every few minutes.

Ice is building a little and leaving haze on the windshield. Because I have a weak flashlight — my eighth mistake — I can't see that the trace of rime has now been covered with a sheet of clear ice — the worst kind. I notice that my altitude is 200 feet low. No problem: I pull back a little on the stick. Nothing happens. I put the throttle in and add some rpm. The airplane is not climbing. I realize at that moment that I'm in trouble.

I squeeze the push-to-talk switch and attempt to speak calmly as I contact Seattle Center. I didn't think about it at the time, but the controller's quick response was probably because I was the only fool currently in his sector. "I am picking up ice and would like to do the one-eighty trick," I say.

"Roger, Eight-Kilo-Tango, one-eighty turn approved, descend and maintain 8,000."

As it turns out, the descent part is easy. The maintain part of the clearance is a problem. Just as I am halfway turned around I feel the prestall shimmy. Luckily the airplane doesn't fully stall. I note with surprise that an iced-up 182 stalls at about 95 kt instead of 45 or 50 kt.

I am happy that I'm keeping the airplane level, and I'm down lower and it seems to be flying again. In my excitement, my instrument scan breaks down. I have altitude and airspeed under control, but I hear, "Eight-Kilo-Tango, what's your heading?"

I'm heading east when I'm supposed to be heading west. Somehow in recovering from the imminent stall, I turned onto my original course.

I'm finally headed west, level at 8,000 feet — and the yoke shudders again, another imminent stall.

I tell Center I'm having trouble maintaining 8,000 feet. Center tells me that the highest terrain in the area is 5,500 feet. "Fly heading 280. In four miles I can give you lower."

A watched GPS doesn't change quickly! My groundspeed is down to 50 kt. I am experiencing moderate turbulence while attempting to fly through the orographic lifting at its strongest and not appreciating it at all. It's still dark outside.

The stall warning horn comes on. I crosscheck the instruments and everything is steady. I decide to ignore the horn, thinking that a piece of ice must be holding the metal tab up.

My friend at Center again: "Eight-Kilo-Tango, fly heading 280; it looks like your current heading will take you into higher terrain."

Holy smokes — I'm heading one-eighty. Even the geographically challenged know that if you go south from V2 you eventually hit Mount Rainier. I look at the turn coordinator — no wonder I'm having so much trouble with heading: The ball is one ball-width to the left of center. I step on the left rudder and the airplane shakes into another imminent stall. I surmise that the ice load is asymmetrical and causing me to fly crooked, or perhaps the rudder has frozen into position, as it doesn't seem very responsive. I don't ponder that too long as I notice I'm descending toward 6,000 feet. I'm now acutely aware that the dirt could start at 5,500 feet.

I level off. Whack! Whack! The ice is releasing. I must be below the freezing level. I gain altitude back up to 8,000 feet, where I'm given a vector and a clearance back down to 4,500 feet.

The stall warning stops. Relative calm ensues. I want to get home, but I realize that home is a narrow 2,300-foot runway and I have no idea if all the airplane's parts are still attached. I request an ILS 17 approach into Olympia, Washington, which is familiar territory complete with a mechanic and a wide 5,400-foot runway. At 15 miles out, I have the runway in sight but I continue on the approach anyway.

NTSB aircraft accident investigators invariably conclude that a chain of errors compound to result in a fatal accident. Since I am still here, I obviously made the right amount of mistakes. I don't want to repeat any of them.

This incident has added one more item to my personal minimums: Don't attempt to fly in the dark when ice is imminent. Had I been able to see the cloud buildup over the Cascades, or what the ice was really doing to my airframe, I would have taken more timely evasive action.

Reilly Glore, AOPA 1347691, is a veterinarian. He is an instrument-rated private pilot with 800 hours and is the owner of a 1972 Cessna 182.

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Posted Thursday, January 09, 2003 2:32:23 PM

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