Accident Probe: Course Reversal In IMC

It’s a maneuver the VFR-only pilot should practice, but probably doesn’t.

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We’ve long maintained that one of the best ways for a pilot to enhance his or her aviation risk management is to earn and use the instrument rating. This is especially true if the pilot in question has plans to use their pilot certificate for transportation on anything resembling a schedule. That’s because the skills, knowledge and experience gained by earning the rating simply help make any flight beyond an airport’s immediate environs more predictable and less risky.

A distant cousin, twice-removed, of the instrument rating is the 180-degree course reversal using the flight instruments alone. Current FAA regulations require every private pilot to have three hours of simulated instrument time before certification, to include “straight and level flight, constant airspeed climbs and descents, turns to a heading, recovery from unusual flight attitudes” and navigation/communication skills. To us, that’s pretty much a bare minimum of instrument training if you plan to travel; it’s probably sufficient if you plan to use the certificate only in good VFR near the departure airport.

If there’s a problem with that rule, it’s that there’s no real requirement to revisit that training, since maneuvers and procedures performed during the flight review are at the instructor’s discretion. That’s as it should be, since someone flying a Piper Cub likely doesn’t have flight instruments, anyway, and imposing some minimum instrument time on them would be unreasonable. But it’s not unreasonable for a pilot flying something else in search of the perfect $100 hamburger to receive some remedial instrument training during the flight review.

If nothing else, the 180-degree course reversal flown by reference to the flight instruments is something that VFR-only pilots should revisit at least as often as during their flight review. It’s a maneuver flight instructors should plan, brief and work on with their students to achieve competency. Here’s an example of why.

Background

On September 19, 2019, at about 1020 Pacific time, a Cessna 182H Skylane was destroyed when it collided with terrain near Nixon, Nevada. The non-instrument-rated private pilot (male, 65) and his passenger were fatally injured. Visual conditions prevailed at a nearby airport, which also reported mountain obscuration in the area of the accident.

The airplane was receiving VFR flight following services from ATC while en route from South Lake Tahoe, Calif., to Nampa, Idaho. As it flew over mountainous terrain, the controller observed the airplane enter a right turn and reverse course. The controller asked the pilot if he was returning, but there was no response. Tracking data generated by ADS-B showed the airplane was in cruise flight at between 10,000 and 10,500 feet MSL over 7500-to-8000-foot-high terrain when it entered a descending right turn and the data stream ended.

Airborne search and rescue efforts were hampered due to limited visibility near the accident coordinates; a ground team subsequently located the accident site in steep mountainous terrain about four hours later.

Investigation

The airplane impacted a steep mountain ridge line just below its top, at about 8000 feet MSL. The airplane was heavily fragmented and exhibited extensive aft crush damage throughout. All flight controls were present, and continuity was established from the control surfaces to the cabin area.

The forward portion of the engine and the propeller were fractured and fragmented. The engine’s pistons showed normal combustion deposits, and connecting rods, valve heads, rocker arms and spark plugs all exhibited normal operating signatures. The carburetor, oil sump, oil filter, magnetos, ignition harness, exhaust and intake were heavily damaged but were otherwise unremarkable. Examination of the airframe and engine revealed no anomalies that would have precluded normal operation.

Weather observations at nearby airports recorded unlimited visibilities underneath several layers of scattered, broken and overcast clouds. An observation about 20 miles southwest of the accident site indicated mountain obscuration to the southwest through northwest. Shortly after the accident occurred, that same facility remarked that mountain tops to the northeast were obscured. Satellite imagery at 1016 indicated cloudy conditions in the accident region with tops estimated at over 20,000 feet. A sounding for the accident site suggested the conditions extended down to about 9000 feet MSL . There were no active advisories for instrument conditions or mountain obscuration at the accident site but there were for nearby locations.

The 450-hour pilot did not hold an instrument rating. The logbook found in the wreckage recorded a total of about three hours of simulated instrument experience but did not state when it was accumulated. No record was located indicating the pilot had received an official weather briefing associated with the accident flight.

Probable Cause

The NTSB determined the probable cause(s) of this accident to include: “A loss of airplane control while maneuvering due to spatial disorientation after inadvertently entering instrument meteorological conditions (IMC). Contributing to the accident was the pilot’s inexperience in IMC conditions.”

According to the NTSB, “It is likely that the airplane inadvertently entered instrument meteorological conditions (IMC) and the pilot initiated a course reversal. During the turn, the pilot may have experienced spatial disorientation as the airplane did not maintain level flight and descended toward the steep terrain.”

The three hours of simulated instrument flight likely were accrued during primary training, to get through the private certificate’s requirements. It’s also likely the pilot had little if any follow-up training or practice in flying by reference to instruments, since it wasn’t logged. That’s a shame, and thorough instructors and conscientious pilots should consider making the 180-degree course reversal a part of their flight review and training curricula.

There’s also the matter of not obtaining a weather briefing. For a cross-country flight over mountainous terrain, not getting a briefing is a cardinal sin. It might not have dissuaded the pilot from tackling the flight, but it would have alerted him to the likelihood of obscured mountains and IMC.


VFR Into IMC: Course Reversals

According to the FAA’s Flight Training Handbook (FAA-H-8083-3B), “The first steps necessary for surviving an encounter with IMC by a VFR pilot are as follows:

  • Recognition and acceptance of the seriousness of the situation and the need for immediate remedial action;
  • Maintaining control of the airplane; and
  • Obtaining the appropriate assistance in getting the airplane safely on the ground.

When performing a turn after inadvertently encountering IMC, the IFH tells us, “A shallow bank takes very little vertical lift from the wings resulting in little if any deviation in altitude. It may be helpful to turn a few degrees and then return to level flight if a large change in heading must be made. Repeat the process until the desired heading is reached. This process may relieve the progressive overbanking that often results from prolonged turns.”


Aircraft Profile: Cessna 182H Skylane

Image: redlegsfan21/Flickr (Not accident aircraft.)

OEM Engine: Continental O-470-R

Empty Weight: 1640 lbs.

Maximum Gross Takeoff Weight: 2800 lbs.

Typical Cruise Speed: 145 KTAS

Standard Fuel Capacity: 65 gal.

Service Ceiling: 18,900 feet

Range: 550 NM

VS0: 48 KCAS


Jeb Burnside is the editor-in-chief of Aviation Safety magazine. He’s an airline transport pilot who owns a Beechcraft Debonair, plus the expensive half of an Aeronca 7CCM Champ.


This article originally appeared in the September 2021 issue of Aviation Safety magazine.

For more great content like this, subscribe to Aviation Safety!

Jeb Burnside is the editor-in-chief of Aviation Safety magazine. He’s an airline transport pilot who owns a Beechcraft Debonair, plus the expensive half of an Aeronca 7CCM Champ.

5 COMMENTS

  1. It isn’t the shallow bank, when a pilot enters IMC while in any flight condition that is changed without first referencing the artificial horizon can bring on vertigo in even a current instrument rated pilot.
    Attempting to turn while experiencing vertigo is suicide. You will most likely be unable to control the aircraft, be it helicopter or plane.
    It doesn’t matter how good you think you are at turning the perfect Coordinated turn. Here is yet another fact… after your perfect 180 degree turn, you aren’t where you entered the clouds and likely will not exit IMC if your turn was level.
    Turning is the exact wrong thing to do if you enter IMC. Keep the plane level and call for help. Only make turns if you feel comfortable. If you feel sick, don’t turn unless you have to. Flying isn’t easy if you are puking like you have the flu. Luck will not help you…

    • Turning around is ok if you have trained for it. I got vertigo in the left seat of a B-52 doing a descending right turn between layers of sloping clouds. I had been trained to believe the instruments and I locked onto the HSI and told my copilot to take the airplane through the turn and level at 10000 feet. There was no reply so for a second I unlocked my twitching eyes to glance at the co-pilot who was barfing in his helmet bag. I managed to level off and shoot an ILS to landing. It was 40 years ago and I remember it like yesterday. Know your target power settings, know your min maneuver speeds, trust your instruments, fly the airplane.

  2. “Current FAA regulations require every private pilot to have three hours of simulated instrument time before certification, to include “straight and level flight, constant airspeed climbs and descents, turns to a heading, recovery from unusual flight attitudes” and navigation/communication skills.”

    Not to quibble, but it should be mentioned that this requirement only applies to single and multi-engine airplane private pilots.

  3. First student solo flight off the airport I euphorically followed the Cumberland River until Nashville ATC informed I would need to change frequencies or turn around. And so I did. 15 miles out from the airport a cloud bank had mechanically marched behind me at pattern alt almost to the turn point it seemed. First thrill with clouds, scud and terror followed. Went home, got the King School course and passed the instrument written before private check ride. Then went directly to instrument training and got the ticket. Never looked back. We do look out for traffic, but I’m always on the needles. Once was enough.