Aero-Tips!

A good pilot is always learning -- how many times have you heard this old standard throughout your flying career? There is no truer statement in all of flying (well, with the possible exception of "there are no old, bold pilots.") It's part of what makes aviation so exciting for all of us... just when you think you've seen it all, along comes a scenario you've never imagined.

Aero-News has called upon the expertise of Thomas P. Turner, master CFI and all-around-good-guy, to bring our readers -- and us -- daily tips to improve our skills as aviators, and as representatives of the flying community. Some of them, you may have heard before... but for each of us, there will also be something we might never have considered before, or something that didn't "stick" the way it should have the first time we memorized it for the practical test.

It is our unabashed goal that "Aero-Tips" will help our readers become better, safer pilots -- as well as introducing our ground-bound readers to the concepts and principles that keep those strange aluminum-and-composite contraptions in the air... and allow them to soar magnificently through it.

Look for our daily Aero-Tips segments, coming each day to you through the Aero-News Network. Suggestions for future Aero-Tips are always welcome, as are additions or discussion of each day's tips. Remember... when it comes to being better pilots, we're all in this together.

Aero-Tips 05.19.06

As a recurrent-training instrument instructor I see an amazing number of IFR pilots who do not regularly check their altimeter for accuracy before taking off. Flying at night or especially in Instrument Meteorological Conditions (IMC) it's vital to know that your altitude-sensing device is accurate (within reason)—your ability to avoid obstacles may be entirely dependent on this device, for which few IFR airplanes have a backup.

The Aeronautical Information Manual (AIM) tells us most pressure altimeters are subject to mechanical, elastic, temperature, and installation errors. In addition to manufacturer and installation quality control and periodic inspection, you can (and should) check the altimeter for errors before flight:

• Set the current reported altimeter setting on the altimeter setting scale.
• • (NOTE: If there is no reported altimeter setting available for your departure airport, set the field elevation on the altimeter and obtain a local altimeter setting from Air Traffic Control, Flight Service or a nearby automated weather as soon as practical once airborne. This will preclude you from testing the altimeter's accuracy on that flight—all the more reason to check it when you can on the ground).
• Altimeter should read field elevation plus or minus 75 feet (the allowable error for IFR operation) if you are located on the same elevation used to establish the altimeter setting (i.e., the taxiways or ramp are level with the published airport elevation).
• • (NOTE: Don't forget to set and check any back-up altimeter, even if it's on the far side of the instrument panel. It must be set before you need it, because you might not have time once you go partial panel. Also, don't get lazy and skip over inputting altimeter setting into a GPS when prompted. The unit needs this for RAIM, and you can use GPS altitude as a back-up if your primary altimeter fails).
• Note any variation between the known field elevation and the altimeter indication. If this variation is in the order of +75 feet, the accuracy of the altimeter is questionable and should be investigated by an instrument technician before flight at night or on an instrument flight plan.

Aero-tip of the day: Check your altimeter for accuracy before you depend on it for obstacle avoidance.

FMI: Aero-Tips