(3) Determination of the total quantity of parts required for maintenance of more than 100 of these equipments can
be accomplished by converting the equipment quantity to a decimal factor by placing a decimal point before the next to
last digit of the number to indicate hundredths, and multiplying the decimal factor by the parts quantity authorized in the
51-100 allowance column. Example, authorized allowance for 51-100 equipments is 40; for 150 equipments multiply 4
by 1. 50 or 60 parts required.
h. 1-Year Allowances Per 100 Equipments/Contingency Planning Purposes'. Indicates opposite the first appearance
of each item the total quantity required for distribution and contingency planning purposes. The range of items indicates
total quantities for all authorized items required to provide for adequate support of 100 equipments for one year.
Subsequent appearances of the same item will have the letters "REF" in the allowance column. Items authorized for use
as required, but not for initial stockage, are identified with an asterisk in the allowance column.
i. Depot Maintenance Allowance Per 100 Equipments. Indicates opposite the first appearance of each item the total
quantity authorized for depot maintenance of 100 equipments. Subsequent appearances of the same item will have the
letters "REF" in the allowance column. Items authorized for use as required, but not for initial stockage, are identified
with an asterisk in the allowance column
(1) Figure number. Indicates the figure number of the illustration in which the item is shown.
(2) Item number or reference designation. Indicates the reference designation used to identify the item in the
D1-4. Special Information.
a. Repair parts mortality is computed from failure rates derived from experience factors with the individual parts in a
variety of equipments. Variations in the specific application and periods of use of electronics equipment, the fragility of
electronic piece parts, plus intangible material and quality factors intrinsic to the manufacture of electronic parts, do not
permit mortality to be based on hours of end item use. However, long periods of continuous use under adverse
conditions are likely to increase repair parts mortality.
b. Parts which require manufacture or assembly at a category higher than that authorized for installation will indicate
in the source column the higher category.