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c.

Some of the safety considerations are:

Area, direction and speed of the intercept;

Aerodynamic effects (i.e., rotorcraft downwash);

Minimum safe separation distances;

Communications requirements, lost communications procedures,
coordination with ATC;

Suitability of diverting the distressed aircraft to the nearest safe
airport; and

Emergency actions to terminate the intercept.

d.

Close proximity, inflight inspection of another aircraft is uniquely
hazardous. The pilot

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in

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command of

the aircraft experiencing the problem/emergency must not relinquish
control of the situation and/or jeopardize

the safety of their aircraft. The maneuver must be accomplished with
minimum risk to both aircraft.

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12.  Precipitation Static

a.

Precipitation static is caused by aircraft in flight coming in contact
with uncharged particles. These particles

can be rain, snow, fog, sleet, hail, volcanic ash, dust; any solid or
liquid particles. When the aircraft strikes these

neutral particles the positive element of the particle is reflected
away from the aircraft and the negative particle

adheres to the skin of the aircraft. In a very short period of time a
substantial negative charge will develop on

the skin of the aircraft. If the aircraft is not equipped with static
dischargers, or has an ineffective static discharger

system, when a sufficient negative voltage level is reached, the
aircraft may go into "CORONA." That is, it will

discharge the static electricity from the extremities of the aircraft,
such as the wing tips, horizontal stabilizer,

vertical stabilizer, antenna, propeller tips, etc. This discharge of
static electricity is what you will hear in your

headphones and is what we call P

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static.

b.

A review of pilot reports often shows different symptoms with each
problem that is encountered. The

following list of problems is a summary of many pilot reports from many
different aircraft. Each problem was

caused by P

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static:

Complete loss of VHF communications.

Erroneous magnetic compass readings (30 percent in error).

High pitched squeal on audio.

Motor boat sound on audio.

Loss of all avionics in clouds.

VLF navigation system inoperative most of the time.

Erratic instrument readouts.

Weak transmissions and poor receptivity of radios.

"St. Elmo's Fire" on windshield.

c.

Each of these symptoms is caused by one general problem on the
airframe. This problem is the inability

of the accumulated charge to flow easily to the wing tips and tail of
the airframe, and properly discharge to the

airstream.

d.

Static dischargers work on the principal of creating a relatively easy
path for discharging negative charges

that develop on the aircraft by using a discharger with fine metal
points, carbon coated rods, or carbon wicks

rather than wait until a large charge is developed and discharged off
the trailing edges of the aircraft that will

interfere with avionics equipment. This process offers approximately
50 decibels (dB) static noise reduction

which is adequate in most cases to be below the threshold of noise that
would cause interference in avionics

equipment.

Potential Flight Hazards

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