10 Feb Trust Your Instruments Especially in the Fog
Though the position of certain instruments in the cockpit on individual private airplanes may vary, the absolute six most important primary flight instruments will always be situated right in front of the pilot. They inform you of the orientation of the plane, giving you its direction, speed, altitude, etc. With your gauges you can get up to the moment status regarding the engine and all of the aircraft’s individual systems. Even the most basic aircraft will provide you information and readings on how much fuel is on board, ammeter, oil pressure, temperature and the tachometer. Even some small aircraft instrumentation gives you pressure readings of the manifold, the rate of fuel flow and the temperature of the cylinder head.
At times a pilot is caught flying through “the soup”, also known as Instrumental Meteorological Conditions (IMC). Many experienced pilots tell stories that they’ve been taught to always trust their instruments when flying under these conditions. Generally, they rely on their instrumentation because they lose all visual cues, become extremely disoriented and can no longer rely on their own senses to tell themselves what’s up and what’s down. Some pilots relay stories of flying through the fog, sure of their direction and orientation, only to find themselves soaring out of the clouds completely upside down.
Riding through the fog without reading your instruments, you can never be 100% sure what is happening, or even close to that percentage. So while it may be true that nearly 100% of the time your instruments don’t lie, they are man-made and capable of malfunctioning. Maybe, instead of stating the fact “you should always trust your instruments”, the statement might be better said to “never trust your own senses”.
The main two instruments you’re going to rely on to pull you through the clouds will be heading and the altitude indicators. However, both of these instruments rely on the same vacuum pump that keeps the gyroscope functioning properly. Should the gyro system fail, the instruments will not be telling you what is actually happening. But any pilot can teach themselves or learn from others, exactly how to cross check their instrument panel. Many instruments on the panel can actually show you different kinds of information other than what they were specifically designed to display.
Consider for a moment that you’re flying and you don’t know what direction is up or down. Your heading indicator and your altitude indicator no longer function. Simply tipping the nose into a dive would let you know if you’re actually dropping in altitude as the airspeed would begin to rapidly increase. The reverse is also true. If you pull back to raise your altitude level the speed should naturally decrease as you climb. If these two things don’t happen then your instruments are telling you what you think is happening, really isn’t. If your airspeed is holding steady then you know that your altitude is also holding steady. Accordingly, if your turn coordinator instrument remained steady, and so does the airspeed you know for the most part you are maintaining your orientation.
It’s always important to verify your instrumentation, even when the skies are clear or anytime when flying VFR. Learning how to use other instruments on the panel to give you information validating what you know to be true, is a valuable way to learn how to fly through “the soup” when the time arrives.