The accident occurred on a cloudy, cold February afternoon in 2021. The National Transportation Safety Board (NTSB) has released its final report, and it contains some clues to the pilot’s thinking. There are no surprising mechanical or meteorological findings. No unexpected revelations. Instead, it was as it initially appeared—a normally functioning airplane flown below the published approach minimums out of the clouds and into the ground.

Cessna 441s are workhorses—this one powered by two 715 hp turboprop engines—and they are popular with charter operators. This 1978 model Conquest II had two pilots in the cockpit. One was a professional 18,000-hour airline transport pilot (ATP), the other a 770-hour pilot with a commercial certificate who had recently retired. It’s unknown who was in what seat, or who was flying at the time of the accident. What we do know is the more experienced pilot had been thinking about the instrument approach at their home airport for hours.

At 9:24 a.m., the ATP-rated pilot called Leidos Flight Service for a weather briefing. The plan was to fly from Belvidere, Tennessee, to Bowman Field Airport (KLOU) in Louisville, Kentucky, on to Thomasville Regional Airport (KTVI) and then return. It was “severe clear” at the destination, but closer to home a cold front was passing overhead. Right away the briefer talked about possible icing, as conditions were conducive for ice to form on wings and propellers in a cloud layer aloft. The briefer said, “The only trials and tribulations you have this morning [are] going to be punching through that layer as quickly as possible, minimizing the time in the clouds.” Asked if he had anti-ice or deice equipment on the Cessna, the pilot replied, “Yep, uh-huh. But I don’t like to use it.” The briefer calculated the icing layer was about 3,000 feet thick, and the pilot wouldn’t be in it long if he climbed at a good rate. The forecast for hat afternoon was for improving weather.

When heading back to home base, the pilots found the weather had not cleared. When they started the approach, the ceiling was 800 feet overcast, visibility 9 sm, with the ground temperature right at freezing, light rime icing conditions in the clouds, and tops of the clouds at about 4,000 feet. But for a Cessna 441, that’s well above the minimums published on the RNAV GPS RWY 36 straight-in approach of 400 feet and 1¼ sm. The final approach track has several altitudes, crossing the fixes at YOKUS at 4,000 feet, and WETSO at 3,000 feet, and with the LNAV/VNAV minimum altitude of 1,367 feet. The runway elevation is 979 feet.

The Cessna correctly crossed YOKUS at 4,000 feet and started a descent. It did not stop as prescribed at 3,000 feet but continued gently descending. At 2,300 feet, the radar data ends, at 2,100 the ADS-B data ends. The airplane hit trees close to the WETSO intersection at an elevation of 1,880 feet. It rolled inverted, hit the ground, and caught fire.

There was no distress call, and no medical or other unusual factors. The NTSB concluded the probable cause to be “the pilot’s failure to follow the published instrument approach procedure by prematurely descending the airplane below the final approach fix altitude to fly under the low ceiling conditions, which resulted in controlled flight into terrain.” It added, “the pilot likely attempted to fly the airplane under the weather to visually acquire the runway.” This might not be as rare as we’d like to think. While staying at published altitudes is a basic safety rule for instrument flying, a 2020 Embry-Riddle Aeronautical University peer-reviewed research study found compliance approaching the runway to be remarkably poor.

In fact, 96.4 percent of the 114 pilots descended below their stated personal minimums on a simulated ILS approach by an average of 303 feet. And 81.5 percent descended below the published federal minimums (by an average of 43 feet). The researchers noted, “These values are highly concerning.” The authors concluded that “pilots are knowingly or unknowingly accepting additional risk during a very critical phase of flight… A simulated (i.e., cash bonus) manipulation designed to mimic external pressures had no effect on pilots’ lowest altitude flown.”

The accident pilot had a possible motivation to descend below instrument altitudes. It’s not discussed by the NTSB, but this incident mirrors a fatal airline accident from December 1, 1993, at what is now called Range Regional Airport (KHIB) in Hibbing, Minnesota. A 19-seat twin-turboprop was on the localizer back course approach to Runway 13. Like other similar aircraft, the Jetstream 3100 was susceptible to tailplane icing. So a technique had evolved among line pilots to minimize their exposure to icing conditions. The NTSB report said the pilot’s “probable intention was to descend at higher than normal rates of speed to minimize the time in icing conditions.”

The Jetstream crew started the approach a little high, above the clouds, and descended at 2,200 feet per minute once on the final course. This high rate of descent inside the final approach fix was against written company procedures, partly because, when leveling out, it leaves little time or space for correcting errors. The airplane quickly descended below the minimum altitude and crashed into woods 4 miles from the airport—at about the same relative runway position as the Cessna 441.

In both accidents, the pilots were trying to manage the threat of airframe icing in the clouds with anti-ice or deice equipment they didn’t completely trust. They were trying to fly safely. And while minimizing time spent in cold, wet clouds is a valid general strategy, rapid descents inside the final approach fix is a dangerous practice. In both cases, no actual airframe icing was observed by investigators.

In trying to avoid icing, the pilots ignored basic instrument flying rules. Good pilots work hard to minimize threats, but sometimes risk management can be like holding too tight to a balloon. Push hard enough in one place, and it blows out somewhere else.

Editor’s Note: This story originally appeared in the October 2023 issue of Plane & Pilot magazine. 

The post After the Accident – Below Minimums appeared first on Plane & Pilot Magazine.

Attendees were able to take part in sessions covering topics as wide ranging as pilot medical concerns, national weather service forecasting support, emergency operations, and air traffic control (ATC) coordination to name a few sessions. Presenters from the Aircraft Owners and Pilots Association, Detroit’s approach control facility, National Weather Service, and industry writers and professionals brought expertise and experience to share.

Some of Michigan’s best flight instructors, promoters of safety, and mechanics also were recognized at the event. As part of the General Aviation Awards program (GAA), Michigan’s winners will be entered into consideration for regional and national recognition. The long-standing awards program is a cooperative effort between many different sponsors and organizations from the aviation industry and FAA.

For more than 50 years, the GAA program has recognized aviation professionals in flight instruction, aviation maintenance, avionics, and flight safety for their important contributions to the general aviation community.

Stephen Tupper was named the East Michigan FSDO CFI of the year’ Daniel Holtzclaw was recognized as the East Michigan FSDO and overall Michigan FAASTeam representative of the year; Marty King earned the Grand Rapids FSDO and overall Michigan aviation maintenance technician of the year; and James Whittles was honored as the Grand Rapids FSDO and overall Michigan CFI of the year.

​The GAA said these awards highlight these individuals’ important leadership roles in promoting aviation safety, education, and professionalism. 

If you missed this year’s Michigan Aviation Safety Forum, keep an eye out for 2025. The MASF is held each February in Ypsilanti and hosted at Eastern Michigan University.

More information on  the MASF event can be found here and here.

The post Michigan Aviation Safety Forum Gathers Mechanics, Pilots for Currency and Proficiency appeared first on Plane & Pilot Magazine.

Nevertheless, the common vernacular is VFR or IFR, so we’ll continue in that vein. Even so, there are degrees of operational difficulty that require modifying the terms. To define simple VFR, we generally regard a cloud ceiling of at least 3,000 feet above ground level, or flight visibility of 5 nautical miles or more, to present little concern for control or navigation. If either of those parameters has a lesser value, the weather is termed “marginal VFR,” as long as it isn’t below what’s stipulated to require adherence to instrument flight rules. Operating in MVFR is a cause for concern, as one may encounter pockets of IFR weather hiding in the murkiness. 

Going further down the scale, IFR conditions are generally regarded as a ceiling of less than 1,000 feet or visibility below 3 statute miles as reported on the ground, which is pretty challenging stuff. Even where it’s legal, visual flight in such conditions is risky at best, capable of turning deadly within minutes. Special training, extra equipment, and adherence to specific procedures are the only way to survive what is essentially “blind flying.” 

And then there’s “low IFR,” or LIFR, denoting really bad weather of less than 500 feet of ceiling or under a mile of visibility. This winter, the Central U.S. experienced a week of widespread conditions with less than a half-mile of visibility and less than 200 feet of ceiling, barely adequate for the sharpest airline crews to operate. Coastal or river valley airports often report low-IFR situations when wide-open VFR prevails a relatively few miles away.

Occasionally, “special VFR,” or SVFR, operations allow a visual-flight alternative to IFR flying, a means of dealing with a local ceiling or visibility that’s just slightly below the 1,000 feet and 3 miles required for controlled airspace. If cleared for a SVFR entry or departure, the pilot will be told to “maintain special VFR,” meaning to stay clear of clouds and keep no less than 1 mile of visibility, effectively turning the Class E or D airspace into Class G. It’s still VFR, but barely.

Unfortunately, reported weather doesn’t always match the actual conditions, making neat categorizations difficult to recognize. On one such day, when a neighboring automated weather station reported 10 miles of visibility and 1,100 feet of ceiling, I sallied forth to relieve ground-bound boredom. The local ceiling turned out to be 700 feet, making for a short flight around the pattern back to the safety of the hangar. As a wise old pilot once reminded me, “the weather is what it is, not what it’s supposed to be.”

The post Good, Bad, and the Really, Really Ugly of Flying Weather appeared first on Plane & Pilot Magazine.

The pilot asking was experienced enough to plan a trip thoroughly but was still learning with every new encounter. Because he wasn’t sure of the significance of “WS020/32020KT” in the Terminal Aerodrome Forecast, he wanted me to give him an up-or-down judgment about going.

Ordinarily, I avoid playing dispatcher when I haven’t been “plugged in” to the weather situation. But I did know a front was moving in, and the time of day was conducive to temperature inversion. Those two factors logically gave rise to the likelihood of low-level wind shear, so I spoke to that effect on his trip. He opted not to go out of an abundance of caution.

For light aircraft, a wind shear note in a TAF is not necessarily a hazardous warning, but a flag that means something is out there, requiring us to be ready to deal with it. It shouldn’t be confused with wind shear alerts generated by LLWAS systems at major airports, which indicate serious, real-time threats. Airliners are maxed out on spare performance capability when taking off and landing, so a loss of airspeed due to a wind shear encounter can be life-threatening.

Piston-engine airplanes flying through changing wind conditions can cope with turbulence and airspeed fluctuations using throttle jockeying and pitch-attitude adjustments. That’s why we fly our approaches at 1.3 VS0 as a speed reference, with half the reported gust spread tacked on for safety, and we’ll lift off and climb out faster in rough air.

So, what’s the issue with those “WS” forecasts? They are telling us there’s a possibility of a change into the noted wind direction and speed at or below the height shown–2000 feet AGL in the opening paragraph. It can be from a frontal passage when the surface wind shifts and the low-level atmosphere gets stirred up by the change. You may take off to the south, then suddenly find yourself battling a northerly wind as you climb out on course. Hopefully, you’ve considered this wind change in your fuel planning.

Any turbulence encountered in the wind shear will generally be short-lived unless your flight profile calls for staying low or there’s perpendicular-oriented terrain upstream. As you climb out, your GPS track will notably shift, requiring a heading change, but the ride will smooth up. In the absence of hills, the rough air comes from the point at which two layers of air are moving in different directions, giving us some piloting to do as we climb or descend through the friction level. 

We used to hear of “low-level jet streams” encountered on clear, cool nights with calm air at the surface. We would find them during climbout, the airplane suddenly bucking and bouncing and then calming down as altitude increased, but with the ground lights moving sideways. I’ve seen 40 knots of wind at 3000 feet AGL, as the cold surface air layer provided a slick cushion for the flow of warm air aloft moving across it. Once up into the inversion, there would be no turbulence, just a massive heading correction.

Therefore, we need to pay attention to the TAF wind-shear notation because it means changes are afoot, but in the absence of other indications, it’s not a reason to scrub a trip. Just be prepared.

The post Is There Shear Up There? appeared first on Plane & Pilot Magazine.