Flight Forum

In "Mastering the Flight Instruments" (February AOPA Flight Training), David Montoya writes what I consider an excellent article about the various instruments available on an aircraft.

While the article is excellent, I feel that it would have been pertinent to add a mention about maneuvering speed. Maneuvering speed or V_A is one of those speeds that is not "marked" on the airspeed indicator, nor are approach speeds or rotation speed, just to mention a few. I have heard many people confuse V_A with V_NO (maximum structural cruise speed) and refer to V_NO as the "safe point" in terms of airspeed when, for example, cruising in turbulent air. I believe V_A should have deserved a special attention in Montoya's article, even when the author is only talking about the instrument displays and what they can teach.

Hugo Sampaio
Toronto, Canada

"Mastering the Flight Instruments" was an excellent article, but Montoya "dropped the ball" by not stressing the importance and relevance of the ball in the turn coordinator instrument. As the name implies, that instrument is only a "coordinator" because of the ball. Without considering the ball (or with a nonfunctioning ball) you then have only yaw rate information and an indirect, unreliable indication of bank. For instance, when doing taxiing S-turns the "little airplane" in the turn coordinator tilts (banks) in the direction of the turn while the ball skids to the outside of the turn - yet the wings have stayed perfectly level! Or, in a forward slip, the wings are severely banked, but the little airplane shows no bank and the ball slips toward the lowered wing.

Only the centrifugal force, which always wants to push the ball to the outside (of an uncoordinated turn), lets the pilot interpret the direction the aircraft is banked or turning.

Vince D'Angelo
Naples, Florida

In the February issue David Montoya states that the turn coordinator indicates bank. To be accurate, the TC gives rate of turn information but may be used to confirm bank information from the attitude indicator (when used in conjunction with the ball).

I thoroughly enjoy your magazine. Keep up the good work.

R. Curry
Via the Internet

I enjoy AOPA Flight Training every month. I just earned my private pilot certificate in January, and I was reading about required flight instruments in the February issue.

Regarding the mnemonics or memory aids for things you need to fly VFR at night, I was taught FLAPS:

F - Fuses

L - Landing lights

A - Anticollision lights

P - Position lights

S - Source (such as battery)

Markus Herm
Via the Internet

Full-flap faux pas

In his article "Learning Experiences: Analyzing an Accident Chain" (February AOPA Flight Training), Stephen Kirby describes his attempt at a go-around with 40 degrees of flaps in a Cessna 172, and adds: "I had been taught not to adjust the flaps until I had a positive rate of climb." Someone (the FAA?) should have a discussion with Kirby's instructor, or perhaps Kirby himself should glance through the Cessna 172 flight manual (and specifically the section on balked landings).

At least Kirby lived to tell about his experience. The pilot and three passengers who tried the same thing at Zahn's Airport on Long Island many years ago were not so lucky.

Jacob Almagor
Via the Internet

"Learning Experiences: Analyzing an Accident" is in serious error. I don't know what kind of pilot Mr. Kirby is, but if he "didn't want the pressure of flying out of Bakersfield Municipal, a towered [sic] airport with traffic and everyone watching," he must be in a different Bakersfield, California.

I'm based in and have flown in and around Bakersfield for many years. Bakersfield Municipal is and has always been a very small, uncontrolled "airpark" with CTAF and the usual traffic being a few little planes each day. About the only ones watching may be the kit foxes, the airport dog, or an occasional airport tenant, because it is virtually dead at Bakersfield Muni, with only one small FBO there. Bakersfield Meadows is the "big" airport, complete with two parallel runways, tower, radar approach control, airlines, numerous FBOs, and aircraft of all sizes.

Greg Dufresne
Via the Internet