Flying Blind: Surviving Instrument Failure (Part 2)

Partial panel flying isn’t hard, but it does take practice — frequent practice — and there are a few tricks that will make your chances of getting home with a partial panel a lot easier. Airplanes come with built-in safety checks that minimize our exposure to risk through system redundancy. When you lose some of that redundancy due to instrument failure, it becomes your job to minimize risk. Safely flying a partial panel means avoiding ALL complicated tasks to ensure simplicity in your actions. You’re a good pilot, now’s your chance to prove your mastery of all of the most basic skills…

Survival Tip #5: Fly Straight and Level As Much As Possible
Unless you know there are obstacles immediately in front of you. If you know you can find VMC by climbing a bit higher, or by flying in one direction for a while, or by descending out of a high overcast — then do it! Tell the controller your plan. If you don’t know where you might find visual weather (and you should have a good idea, from your preflight planning), then ask. ATC will tell you, or if they don’t know, they’ll query other pilots in the area for pilot reports. In a worst-case scenario, when you have to fly an approach *now* ask for small heading changes toward the nearest ILS airport. Otherwise, have the controller guide you to the best-equipped, most familiar airport in your repertoire. Failing that, go out of your way for a glideslope (or a military radar approach).

Survival Tip #6: Make SMALL Control Inputs
Like Han Solo said in Return of the Jedi, fly casual. Don’t upset the cart by trying to make big pitch, bank or power settings. Use half-standard-rate turns — or less — and gradual power changes. Move the trim as little as possible while you re in IMC. Chances are your airplane was trimmed when the instrument died and it won’t go out of trim just because you can’t read one of the gauges. All you have to do to survive is to gently fly the airplane into visual conditions. On the way you should perform…

Survival Tip #7: Fly Known Power Settings and Configurations
Experiment a little next time you re aloft in *visual* conditions — it will save you unnecessary experimentation when you’re IFR and an instrument dies. Know what power, flaps and landing gear position it takes to fly level on a localizer at approach speed. Note the trim setting (the position indicator, if your airplane has one, or the physical position of the trim wheel). Unless there’s a very good reason not to, get some altitude by going to climb power in a clean configuration at that trim setting. Watch and mentally record how the airplane performs, so you’ll know what to expect in a partial panel situation. Then, find out what you need to do to descend at about 500 feet per minute at the same airspeed. Hint: If your gear retracts, extending the gear usually does it. In fixed-gear airplanes it’ll take a few inches of manifold pressure drop, or reduction of propeller speed by a couple hundred rpm, to set up this descent. It should take little or no change in the trim position.

Payoff: If someday you go partial panel for real, you’ll already know what trimmed configuration will hold you level at a safe speed, what climb rate to expect at full power and set trim and what action will allow for a safe descent at a glideslope angle. With this knowledge, it might turn out to be not such a bad day, after all.

The truth is, that flying partial panel isn’t the hard part. The real challenge is flying through the identification steps before covering up a dead gauge. Get to a simulator (PCATDs and desktops sims are almost as good as the full-motion behemoths for this), and get some dual in detecting and identifying a failed instrument. Practice in flight the process of slowly establishing that approach configuration and transitioning to a 500-foot-per-minute descent. Every time you do this, you increase your chances of surviving a partial panel approach. Do as often as is practical.

BOTTOM LINE: If you’ve survived the process of correctly identifying the failed instrument(s), you can make it home. Just remember: keep your cool, keep it simple and get help.