Survive Inadvertent IMC The Old-Fashioned Way

if youve been around general aviation for any time at all, by now you should not be surprised to learn that attempted VFR flight into instrument metereological conditions (IMC) and its close cousin, loss of visual references at night, consistently rank as the most lethal type of GA accidents. Although the numbers (thank goodness!) have recently begun to decline, about seven out of every eight-nearly 90 percent-of those accidents are still fatal. Thats largely because, as current NTSB Vice Chairman Bruce Landsberg puts it, they tend to end in flight into terrain, either controlled or (more often) uncontrolled. In both cases, prospects for survival are meager.

David Jack Kenny

Sunday, March 17, 2019 at 12:00 AM ET

Verified

Reproduced here, and below, are instructor’s notes made during training flights with subject 13. When the study began, this person was 48 years old and held a private certificate. The non-instrument-rated pilot had accrued some 500 hours’ total flight time in an Ercoupe, a Stinson 150 and a Cessna 140. At the beginning of the study, the pilot needed only 124 seconds—far short of the 178-second average—to lose control.

Key Takeaways:

A 1954 University of Illinois study highlighted the extreme lethality of VFR flight into Instrument Meteorological Conditions (IMC), finding non-instrument-rated pilots typically lose control in an average of 178 seconds.
The study developed a simple, effective, and easily teachable technique for VFR pilots to regain control and reverse course or descend through IMC using only basic panel instruments (altimeter, airspeed, turn coordinator).
After just a few hours of training, pilots improved from 0% successful recoveries to 59 out of 60 successful attempts, primarily by taking hands off the controls, reducing power, re-trimming, and making a gentle rudder-induced turn.
Despite its proven success, this specific "180-Degree Rating Course" was later replaced by a broader 3-hour instrument training mandate in 1960, raising questions about whether current emergency training adequately prepares VFR pilots for inadvertent IMC encounters.

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Editor’s Note: A sidebar in Mike Hart’s February 2019 “Losing Orientation” highlighted a 1954 University of Illinois study finding that a non-instrument-rated pilot who inadvertently encounters instrument conditions will last, on average, 178 seconds before losing control. We thought the study deserved some additional scrutiny.

If you’ve been around general aviation for any time at all, by now you should not be surprised to learn that attempted VFR flight into instrument metereological conditions (IMC) and its close cousin, loss of visual references at night, consistently rank as the most lethal type of GA accidents. Although the numbers (thank goodness!) have recently begun to decline, about seven out of every eight—nearly 90 percent—of those accidents are still fatal. That’s largely because, as current NTSB Vice Chairman Bruce Landsberg puts it, they tend to end in flight into terrain, either controlled or (more often) uncontrolled. In both cases, prospects for survival are meager.