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Common Threads In Weather Accidents

In my view, there are four basic categories of aviation weather threats: low clouds and reduced visibility; turbulence and low-level wind shear; airframe ice; and thunderstorms (which may contain the three other hazards in one nasty package). When evaluating weather for a planned flight, I look at observations and forecasts with each of these specific hazards in mind: what is are the chances Ill encounter each threat and how bad will each be? How close to (or beyond) the limitations of the regulations, my capabilities and the airplanes performance would I be if I attempt the flight?


While in IFR cruise at 4000 feet, the pilot observed the flight director command bars move out of view as the airplane started a gradual descent. When the pilot corrected, the electric trim started to run nose down and the aircrafts descent rate increased. The pilot attempted to disconnect the autopilot and trim with the control switches and the red disconnect switch. None of this had any effect. With the turbulence and conditions, the pilot was unable to reach the autopilot and electric trim circuit breakers. After all other remedial procedures had failed, he shut off the avionics master switch at about 1000 feet and recovered the airplane at about 500 feet.

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.

Single-Stage Go-Around

Convincing the airplane that youve changed your mind and now want to climb-at the best rate, by the way-requires adding power, arresting the descent and beginning a climb, reconfiguring the airplane and ensuring directional control. While the order in which we perform these tasks varies-check your POH/AFM for the details-we still have to fly the airplane as we accomplish them. That means we can be tempted to add full power when doing so is probably not what we want to do.

NTSB Reports

Upon raising the landing gear after takeoff, the gear motor continued to operate longer than normal, and the pilot heard an abnormal sound toward the end of the sequence. The right main gear was hanging at about a 45-degree angle, and the left main gear was not visible. The pilot completed the appropriate checklists, without change. The pilot declared an emergency and ATC confirmed during a fly-by that the main gear was not extended. During the landing, the nose gear remained extended and the two main gear were retracted. The airplane came to rest on the runway and the passengers egressed without further incident.

Retractable Gear Systems

The first evidence of a retractable landing gear design was in Europe circa 1911, but a working example didnt show up on aircraft until after WWI. As airplanes got heavier and faster, meanwhile, airport infrastructure-which mainly consisted of an open field and a windsock- couldnt keep up. As a result, some of the fastest airplanes in the 1920s and 1930s were seaplanes, even with the aerodynamic drag their floats imposed. By the time WWII erupted, the latest airplanes were equipped with retractable landing gear, even if in a conventional, taildragging configuration. Still, many long-range, multi-engine airliners of the day were seaplanes.

Passing The Ride

Expecting that I had somehow unknowingly blown my check ride, we landed, shut everything down and he informed me I had...well...passed! A bit confused but obviously glad I hadnt actually blown it, I accepted the good news not wishing to open my mouth and undo it, and simply thanked him. I never told my instrument instructor what the examiner had said, only that he passed me.

The Transactional Pilot

The advent of the direct to GPS button, which allows us to fly a straight line between two points, was instant gratification for efficiency-loving pilots, especially since IFR flights no longer needed to fly inefficient tinker-toy flight paths connecting VORs as long as ATC cooperated. But instant gratification also came with instant risk tradeoffs. The biggest of them is not obvious until you look beneath the magenta flight path where there might not be many, or any, airports.

Exhaust Essentials

The first order of business in the inspection process is to become familiar with the specific exhaust system and components so that the aircraft is maintained in the desired condition. As always, the place to start is the manufacturers maintenance and parts manuals. This is also true when considering an aftermarket exhaust system, including turbochargers, typically installed according to a supplemental type certificate (STC). Aftermarket exhaust and turbocharger providers like Power Flow and Tornado Alley Turbo offer documentation at least as good as the airframe manufacturers, including installation instructions, parts manuals and instructions for continued airworthiness.

Download The Full February 2019 Issue PDF

  • The Big Picture
  • Top Ten Tips
  • Trim Runaways
  • Disoriented
  • Bounced Landings

Control System Servos

At FL400, the autopilot started porpoising and was turned off. Afterward, the aircraft would not trim properly. The crew diverted; it was difficult to keep it pitched down while descending. During the final phase of flight, the yoke was very difficult to input pitch changes, but was okay in the roll axis. After landing, troubleshooting duplicated the problem. Elevator servo (p/n 4006719914) was replaced with serviceable unit.

The Big Picture

I ts widely accepted that having good situational awareness is vital to safe and efficient flying. But what does situational awareness even mean? How do we develop and maintain the good kind? How do we fit ourselves into the big picture, and why is it important to do so? And once we understand these aspects of situational awareness, how can we use it to make things easier? On three recent flights, I feel I had a high level of situational awareness and used it to make a difference. In one I used my knowledge of my place in the big picture to help another pilot. In the second I used it to help myself. In the third I used it to eliminate a possible delay on an approach. Heres what Im talking about.