AMf01018
Figure 1-18.--Stationary pit-type scales.
Weighing Accessory Kit
STEEL TAPES.--Use a steel tape 600 inches in
length and graduated in inches and tenths of inches. All
It may be necessary to prepare special devices that
weighing dimensions must be read to one-tenth of an
will aid in taking measurements and leveling specific
inch, and are frequently read to one-hundredth of an
types of aircraft. To measure such data as lengths,
inch. Using this type of tape reduces the possibility of
angles, and densities, weight and balance personnel
errors associated with converting common fractions to
require accessories, such as levels, plumb bobs,
decimals. These tapes are usually found in the weighing
measuring tapes, chalk lines, and hydrometers. Some
kit.
types of aircraft require special equipment. The
CHALK LINE.--This is a string that is covered
equipment will be assembled into a specific type of
with chalk and used to mark a straight chalked line on
aircraft kit.
the hangar floor. It is used between the vertical
SPIRIT LEVEL.--At least one spirit level is
projections of specified jig points. The string should be
required for leveling most aircraft. Two levels are
sturdy and hard finished. It usually accompanies the
generally recommended. Use one 24-inch level for
weighing kit.
spanning distances between leveling lugs. Use a 6-inch
HYDROMETERS.--Use a hydrometer with a
level for use in places where sufficient space is not
calibration range from 5.5 to 7.0 pounds per US gallon
available for seating a 24-inch level. The levels should
for determining the density of fuel. A transparent
be a machinists' bench type of first-class quality.
container for holding fuel samples, a pipette at least 12
LEVELING BARS.--Several leveling bars of
inches long, or some other similar device for
varying lengths are needed for spanning the distances
withdrawing samples from the tank, is necessary for
between leveling lugs. One set of bars usually comes
use with the hydrometer. You must take care not to
with the weighing kit, which is normally maintained by
damage the glassware. To determine the density of a
each Naval Aviation Depot (NADEP).
fuel sample, you should carefully place the hydrometer
into the fluid within the transparent container. The
PLUMB BOBS.--Plumb bobs are used to project
hydrometer must not touch the container when you are
points on the aircraft onto the floor for measuring
reading the density, and you should take the reading at
dimensions in a level plane. Each plumb bob should
the lowest fuel point.
have a slot in the head so that excess string can be
wound around the neck. Plumb bobs are normally
NOTE: The hydrometer is used to determine fuel
included in the weighing kit.
density for full fuel weighing. Since full fuel weighing
1-23
