Subject: Thunderstorms; Purpose; Cancellation; Related Reading Material - Honeywell PRIMUS 660 Pilot's Manual

COMBUSTIBLE MATERIALS
To prevent possible fuel ignition, an insulated airborne weather radar
should not be operated while an aircraft is being refueled or defueled.
M.C. Beard
Director of Airworthiness.

SUBJECT: THUNDERSTORMS

Purpose

This advisory circular describes the hazards of thunderstorms to
aviation and offers guidance to help prevent accidents caused by
thunderstorms.

Cancellation

Advisory Circular 00–24A, dated June 23, 1978, is cancelled.

Related Reading Material

Advisory Circulars, 00–6A, Aviation Weather, 090–45B, Aviation
Weather Services, 00–50A, Low Level Wind Shear.

General

We all know what a thunderstorm looks like. Much has been written
about the mechanics and life cycles of thunderstorms. They have been
studied for many years; and while much has been learned, the studies
continue because much is not known. Knowledge and weather radar
have modified attitudes toward thunderstorms, but one rule continues
to be true – any storm recognizable as a thunderstorm should be
considered hazardous until measurements have shown it to be safe.
That means safe for you and your aircraft. Almost any thunderstorm
can spell disaster for the wrong combination of aircraft and pilot.
A28–1146–111
REV 2
R
PRIMUS
Federal Aviation Administration (FAA) Advisory Circulars
660 Digital Weather Radar System
A–3