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e.

It is important to remember that precipitation static problems can only
be corrected with the proper number

of quality static dischargers, properly installed on a properly bonded
aircraft. P

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static is indeed a problem in the

all weather operation of the aircraft, but there are effective ways to
combat it. All possible methods of reducing

the effects of P

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static should be considered so as to provide the best
possible performance in the flight

environment.

f.

A wide variety of discharger designs is available on the commercial
market. The inclusion of well

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designed

dischargers may be expected to improve airframe noise in P

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static conditions by as much as 50 dB. Essentially,

the discharger provides a path by which accumulated charge may leave
the airframe quietly. This is generally

accomplished by providing a group of tiny corona points to permit onset
of corona

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current flow at a low aircraft

potential. Additionally, aerodynamic design of dischargers to permit
corona to occur at the lowest possible

atmospheric pressure also lowers the corona threshold. In addition to
permitting a low

-

potential discharge, the

discharger will minimize the radiation of radio frequency (RF) energy
which accompanies the corona discharge,

in order to minimize effects of RF components at communications and
navigation frequencies on avionics

performance. These effects are reduced through resistive attachment of
the corona point(s) to the airframe,

preserving direct current connection but attenuating the higher

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frequency components of the discharge.

g.

Each manufacturer of static dischargers offers information concerning
appropriate discharger location on

specific airframes. Such locations emphasize the trailing outboard
surfaces of wings and horizontal tail surfaces,

plus the tip of the vertical stabilizer, where charge tends to
accumulate on the airframe. Sufficient dischargers

must be provided to allow for current

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carrying capacity which will maintain airframe potential below the
corona

threshold of the trailing edges.

h.

In order to achieve full performance of avionic equipment, the static
discharge system will require periodic

maintenance. A pilot knowledgeable of P

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static causes and effects is an important element in assuring optimum

performance by early recognition of these types of problems.

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13.  Light Amplification by Stimulated Emission of Radiation (Laser)
Operations and

Reporting Illumination of Aircraft

a.

Lasers have many applications. Of concern to users of the National
Airspace System are those laser events

that may affect pilots, e.g., outdoor laser light shows or
demonstrations for entertainment and advertisements at

special events and theme parks. Generally, the beams from these events
appear as bright blue

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green in color;

however, they may be red, yellow, or white. However, some laser systems
produce light which is invisible to the

human eye.

b.

FAA regulations prohibit the disruption of aviation activity by any
person on the ground or in the air. The

FAA and the Food and Drug Administration (the Federal agency that has
the responsibility to enforce compliance

with Federal requirements for laser systems and laser light show
products) are working together to ensure that

operators of these devices do not pose a hazard to aircraft operators.

c.

Pilots should be aware that illumination from these laser operations
are able to create temporary vision

impairment miles from the actual location. In addition, these
operations can produce permanent eye damage.

Pilots should make themselves aware of where these activities are being
conducted and avoid these areas if

possible.

d.

Recent and increasing incidents of unauthorized illumination of aircraf
t by lasers, as well as the

proliferation and increasing sophistication of laser devices available
to the general public, dictates that the FAA,

in coordination with other government agencies, take action to
safeguard flights from these unauthorized

illuminations.

e.

Pilots should report laser illumination activity to the controlling Air
Traffic Control facilities, Federal

Contract Towers or Flight Service Stations as soon as possible after
the event. The following information should

be included:

UTC Date and Time of Event.

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Potential Flight Hazards