2-1. Preoperation Procedure.
a. Check fixed operating equipment with Ba-
a. Unreel cell cables and connect them to
sic Weight Checklist appearing in Weight and Bal-
proper cells, observing color codings (red-to-red
ance data of aircraft involved. Be sure all items on
aircraft are checked on list. Add to list any fixed
equipment that has not been listed.
Do not interchange cells and cables.
b. Remove all loose equipment.
c. Clean aircraft to remove any accumulated
or 1-3) to OFF. Switch AC or DC selector switch
dirt and grease,
(2) to 110-volts ac or 24-volts dc, depending on
power source used,
d. Drain oil from all tanks or fill to known ca-
pacity. Fill all reservoirs with proper liquid to nor-
(1) If 110-volts ac is used, connect 25-
mal operating levels.
foot extension cable (8, fig. 1-4) between ac outlet
in power supply unit and 110-volt power supply.
Press BATTERY VOLTAGE switch (3, figs. 1-2 or
Fumes of most aircraft fuels and sol-
1-3) on indicator panel. Turn AC VOLTAGE AD-
vents are highly toxic, especially if they
JUSTMENT knob (4) until pointer of balance me-
contain TCP. Avoid extended inhalation
ter rests in center of green area on scale of milli-
of fuel odors. Fuels and solvents shall
be used only in well ventilated areas.
(2) If 24-volts dc is used, connect 15-foot
e. Drain fuel tanks. If draining is not feasible,
power cable (9, fig. 1-4) from male connector on
determine quantity of fuel in aircraft using a cal-
right-hand side of indicator to power supply. Bat-
ibrated tank dipstick, fuel tank manometer, or
tery clips are also provided. Turn AC or DC se-
electric gages. Aircraft should be in position for
lector switch (2, figs. 1-2 or 1-3) to 24 VDC BATT
which instrument is calibrated--usually flight level.
position. Attach clips of battery cable (10, fig. 1-4)
f. Determine the unit weight of the fuel. Obtain
to battery terminals if battery is used. Press BAT-
a sample from the tank with fuel dipper (1, Figs.
TERY VOLTAGE switch (3, figs. 1-2 or 1-3) and
or 4-27). Slowly and carefully pour the sample
check for polarity. If pointer swings to yellow sec-
into a clean, dry hydrometer cylinder, filling the
tion of milliammeter scale, leads must be re-
cylinder approximately three quarters full.
versed. After leads are changed, press switch
the hydrometer gently in the sample, and when it
again. If pointer rests in red section of scale dc
has settled, push it down appraximately two scale.
voltage is either too high or too low for proper
divisions into the liquid and release it.
operation. Replace with a battery of proper volta-
push it all the way down; wetting the upper part of
ge or adjust power supply voltage accordingly.
the stem wiII make test results false.
Check power frequently to assure that
To obtain actual weight, multiply the weight
correct voltage is maintained. Unless
read from the weighing kit indicator by the
constant voltage is maintained through-
correction factor for the latitude at which the
o u t weighing operation, inaccurate
readings may result.
c. Keep power on and allow equipment to
warm up for a minimum of 20 minutes. Aircraft
g. Inflate or deflate main gear oleo struts to
may be prepared for weighing during warmup pe-
normal extension or anticipated desired height. If
all wing jacks or a combination of wing and axle
jacks are being used, restrain shock struts to pre-
vent them from extending when aircraft is lifted