JPATS Weather - NETC

JPATS AVIATION WEATHER BOOKLET
Penetration Procedures
Figure 5-12 — Through the Thunderstorm
Figure 5-13 — Thunderstorm Penetration
The faster a plane is going when it strikes an updraft or downdraft, the greater the shock. Refer to
your flight manual for the recommended turbulent air penetration speed.
Once inside the storm, the pilot should let the plane ride out the updrafts and downdrafts and
concentrate on maintaining a level attitude. With power set to maintain the proper airspeed,
maintaining the same attitude will result in only minor airspeed variations. However, the
aircraft’s altitude may vary by thousands of feet. The rapidly changing pressure conditions
within the storm will result in unreliable indications and erratic variations in altitude, airspeed,
and rate of climb instruments. Since the attitude gyro is independent of the pitot-static system, its
indications should be considered reliable.
If thunderstorm penetration is unavoidable or you inadvertently fly into a thunderstorm, follow
these procedures:
1. Secure all loose objects, tighten your lap belt and lock your shoulder harness. Turn cockpit
lights up to highest intensity.
5-12 Version 3.2/Dec 08