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 04.04.06

Arriving at a commercial-service airport in poor visibility?  Listening to ATIS (the Automated Terminal Information System) you may hear "RVR"-- the Runway Visual Range.

RVR values are measured by transmissometers mounted on 14-foot towers along the runway, 250 feet apart. A known-intensity of light is emitted from the projector and is measured by the receiver. Any obscuring matter such as rain, snow, dust, fog, haze or smoke reduces the light intensity arriving at the receiver. The resultant intensity measurement is then converted to an RVR value by the signal data converter. These values are displayed by readout equipment in the associated air traffic facility and updated approximately once every minute for controller issuance to pilots.

Minimum measured visibility is 600 feet (1/10th nautical mile).  Higher visibilities are reported in 200-foot increments up to a maximum value of 6000 feet (one nautical mile).

Note: this differs from other visibility measurements, which are reported in statute miles.

Air Traffic Control Towers report RVR when:

• it is available,
• the prevailing visibility is one (statute) mile or less, and/or
• the measured RVR is 6000 feet or less.

Instrument  Approach categories with the corresponding minimum RVR values:

AIM TBL 7-1-5

• Category        Visibility (RVR)
• Nonprecision   2,400 feet
• Category I      1,800 feet
• Category II     1,200 feet
• Category IIIa  700 feet
• Category IIIb  150 feet
• Category IIIc   0 feet

Aero-tip of the day:  Expect to hear "RVR" values when landing at a large airport in poor visibility.

FMI: Aero-Tips