considered to be the typical requirements to keep the equipment in good condition. The
frequency of a particular PMI should be justified after experience is gained under local operating
Record Retention. There is no set period of time that maintenance records should be
kept, but, in keeping within the goals mentioned above, a period of twice the longest period
recorded would be minimum (e.g., 2 years in the case of annual maintenance action). Records of
daily inspection will, of course, lose their significance much sooner (probably within a month).
Reference Library. A reference library should be established to maintain a master
copy of all equipment technical manuals, advisory circulars, as-built drawings, and other useful
technical data. An office of primary responsibility should be established to maintain records.
Equipment Technical Manuals. Equipment technical manuals and other
manufacturer's literature form an important part of the reference library. Two copies of all
technical manuals and related manufacturer's literature should be obtained. A master copy is
retained in the reference library, and a photocopy is provided for the shop. The master copy of
the manuals should not be removed from the reference library because it can easily be misplaced
or lost. If the shop copy is lost, another photocopy of the manuals should be made from the
reference library instead of releasing the master copy.
FAA Advisory Circulars (ACs). Important reference information on installation,
design tolerances, and operation of lighted navigational aid equipment may be found in FAA
ACs. A copy of the ACs covering the equipment at the facility should be included in the
reference library. A partial list is shown in Table 1.
Other Technical Data. Other less frequently used reference information should also be
added to the library. This might include local electrical codes, engineer's handbooks, test
equipment manuals, and other general information publications. For a listing of DOD reference
material, see Table 3.
As-built Drawings. It is recommended that the master copy of as-built drawings be
maintained as part of the reference library. Modifications to any equipment should be
incorporated into the drawings as soon as the modification is completed. A copy of the as-built
lighting plan, showing the location of all cable runs, runway lights, etc., and including the wiring
diagrams for the lighting, engine generator, and the lighted navigational aid, should be given to
the field technicians as a working copy.
Spare Part Provisioning. This paragraph contains guidelines on how to establish a
stock of spare parts to be used for quick repair of lighting equipment that fails unexpectedly.
The purpose of a spare parts system is to have the necessary part on-hand when a piece of
equipment fails; minimizing the time the system is out of operation. However, the greater the
number of spare parts stored, the greater the inventory costs. The optimum spare part system
balances the cost of system downtime (lost operations, tenant inconvenience, etc.) with the cost
of purchasing and storing spare parts. A small facility with few operations may suffer little
inconvenience with the loss of their lighting system and may, therefore, choose to stock few
spare parts. A large facility may rely heavily on its lighting system for bad weather operations