1. Tighten your safety belt, put on your shoulder
harness (if installed), if and secure all loose objects.
2. Plan and hold the course to take the aircraft
through the storm in a minimum time.
3. To avoid the most critical icing, establish a
penetration altitude below the freezing level or above
the level of -15C.
4. Verify that pitot heat is on and turn on
carburetor heat or jet engine anti-ice. Icing can be
rapid at any altitude and cause almost instantaneous
power failure and/or loss of airspeed indication.
5. Establish power settings for turbulence
penetration airspeed recommended in the aircraft
manual.
6. Turn up cockpit lights to highest intensity to
lessen temporary blindness from lightning.
7. If using automatic pilot, disengage Altitude
Hold Mode and Speed Hold Mode. The automatic
altitude and speed controls will increase maneuvers
of the aircraft thus increasing structural stress.

Meteorology

8. If using airborne radar, tilt the antenna up and
down occasionally. This will permit the detection of
other thunderstorm activity at altitudes other than the
one being flown.
c. Following are some Do"s and Don"ts during the
thunderstorm penetration:
1. Do keep your eyes on your instruments.
Looking outside the cockpit can increase danger of
temporary blindness from lightning.
2. Don"t change power settings; maintain
settings for the recommended turbulence penetration
airspeed.
3. Do maintain constant attitude. Allow the
altitude and airspeed to fluctuate.
4. Don"t turn back once you are in the
thunderstorm. A straight course through the storm
most likely will get the aircraft out of the hazards
most quickly. In addition, turning maneuvers increase
stress on the aircraft.

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