Issue Number 225
January 1999
A Monthly Safety Bulletin from The Office of the NASA Aviation Safety Reporting System
P.O. Box 189, Moffett Field, CA 94035-0189

"VFR into IMC" with an Aircraft Flying Into Cumulonimbus Clouds

Instrument Meteorological Conditions (IMC) manage to sneak up on many pilots. Two ASRS reports of unintentional brushes with IMC show how easily a pilot can be caught by surprise. The first reporter, a low-time private pilot, sought ATC assistance for the IMC dilemma, and unwittingly became the recipient of an unwanted IFR clearance.

The controller did an admirable job of getting the pilot out of the clouds. An up-to-date weather briefing prior to the delayed departure might have encouraged the reporter to choose a destination more likely to remain VFR, or alternatively, to stay on the ground. Then, when stuck in IMC, this non-IFR-rated pilot would have received better ATC service by immediately admitting the lack of an instrument rating.

The next reporter hoped to avoid the forecast midday thunderstorms by departing in the early morning. Alas, the thunderstorms didn't read the forecast.

Taking the conservative route -- doing a 180 degree turn -- is usually the better bet when facing IMC. Kudos to the sharp Center Controller for safely resolving this pilot's emergency.

Not Good Form

In our next report, the commuter crew were flying in VMC on an IFR flight plan, but both were distracted from their flying and monitoring duties by Customs forms that could have waited until the flight had landed.

The Captain filed this report to document the uncommanded disengagement of the autopilot. However, automation -- the "Magic" -- is never a substitute for flying the aircraft. The reminder for all is that the crew's first priority should always be on flying duties, including altitude callouts, checklists, and traffic watch. Ground duties should be saved and performed on the ground.

"Dry Dust and Stray Paper..." Ezra Pound with Aircraft leaving trail of Papers

Many pilots would prefer to avoid dealing with aircraft paperwork and logbooks. But, as the following report describes, a General Aviation pilot's look into old paperwork yielded a very serious discrepancy.

Dry and dusty as they may be, aircraft records often contain a wealth of interesting information -- and possibly some discrepancies, too.

An air carrier Captain provides a report about a piece of paper that is a frequent source of confusion to pilots -- the aircraft MEL (Minimum Equipment List):

Since MELs are generally not written in "plain English," repeated readings may be required for complete understanding of their limitations and allowances. In addition, direct contact with the Maintenance Control Department may provide clarification that a dispatcher or other pilot cannot offer.

The Color of Caution

Perhaps the most commonly misread piece of paper is the aircraft checklist. This report of a checklist incident was submitted by an air carrier Captain.

This incident could have been avoided by more careful consideration of each individual checklist item, rather than rote responses to the familiar pre-takeoff agenda.

Stray Blue Sheet

A corporate pilot reports that one more bit of stray paper, a recent issue of CALLBACK, made an impression. Apparently not quite a big enough impression...

The last two numbers of the altimeter setting were so close that it didn't register with the reporter that the first two numbers were a problem -- the 28 should have been a 29.

ASRS Recently Issued Alerts On...
EMB-120 electronic engine control malfunction
B-737-800 leading edge flaps/slats malfunction
Failure of a B-757 left hydraulic system during takeoff
Ignition hazard of wooden matches in passenger baggage
Turboprop / parachutists near-collision near a New Jersey airport
November 1998 Report Intake
 Air Carrier/Air Taxi Pilots 1,968
 General Aviation Pilots 685
 Controllers 63
 Cabin/Mechanics/Military/Other 181
 TOTAL 2,897