Section II. CONTROLS AND INSTRUMENTS
2-2.
General
or to the pump when the control valve (25) is closed. It is
This section describes the controls and instruments of
set prior to flight as stated in the flight and spray plan.
the insecticide sprayer and liquid loading system. It also
The valve is hand set to one of two positions, closed or
provides information needed to insure proper operation
open. The handle position is marked on the valve
of the equipment.
casting.
b. Liquid Loading System. The following controls
2-3. Controls and Instruments
used in pump operation are mounted on the pump
a. Insecticide Sprayer. The following controls and
engine (fig. 11-2):
instruments are installed on the insecticide sprayer for
(1) Starting rope grip. The starter grip (9) is
use in flight operations.
attached to a starting cord. Pulling the starter grip turns
(1) Manual control panel. A manual control panel
the engine for starting.
(26, fig. 1-2) is mounted on the front side of the tank
(2) Choke button. The choke button (20) is used
assembly, between the pilot and copilot seats. The
when starting a cold engine. Pulling the choke button
control panel contains a pump brake lever (29), a valve
partly out decreases air supply to the engine.
control lever (27), and a pressure gage (28). The pump
(3) Ignition ON/OFF switch.
The ignition
brake lever is used to hold or free the windmill for
ON/OFF switch (24) must be ON for starting engine.
operation, as required. The valve control lever is used to
Placing switch to OFF stops engine.
control flow of liquid to the spray booms. Instruction
(4) Throttle button. The throttle button (28) is
plates showing the control positions are placed next to
used to control gas flow to the engine. Pushing button in
both valve levers. The pressure gage, within a range of 8
causes engine to speed up. Pulling button out slows
to 100 psi in 2 psi steps, is mounted on top of the manual
engine speed.
control panel. The pressure gage reads insecticide fluid
(5) Pump outlet ball valve. The pump outlet ball
pressure at the center of the spray booms.
valve (2, fig. 11-1) is set by hand to block the pump
(2) Bypass valve. A bypass valve (24, fig.1-2) is
outlet port. It is used to control insecticide flow when
installed partly beneath the tank, between and behind the
filling tank on insecticide sprayer. Closing this valve also
crew seats. The bypass valve is attached to the tank and
keeps fluid in the pump when test running the engine.
opens into the tank. It is used to direct spray fluid back
The valve is closed when the handle is across the tube.
into
the
tank
Section III. OPERATION UNDER USUAL CONDITIONS
2-4.
General
paragraph 34. Refer to paragraph 2-7 for operating
a
The instructions in this section are to inform
procedures.
and guide personnel operating the aircraft mounted
b. Liquid Loading System. Before starting the liquid
insecticide sprayer and liquid loading system.
loading system pump, perform the check list of
b.
The operator must know how to perform
Perform any preventive
every operation of which the insecticide sprayer and
maintenance checks and services found necessary as
liquid loading system are capable. This section contains
listed in paragraph 11-4. Start the liquid loading system
instructions on starting, stopping, and operating the
pump as outlined in the following steps (fig. 11-2):
insecticide sprayer and liquid load ing system, and on
CAUTION
coordinating the basic motions to perform the specific
Before starting the engine for the first time after
tasks for which the equipment is designed. Since nearly
unpacking (refer to para 4-2, step b), remove spark plug
every job presents a different problem, the operator may
and turn engine over several times to prevent hydrostatic
have to vary given procedures to fit the individual job.
lock.
2-5.
Starting
(1) If engine is cold, loosen fuel filler cap (8). This will
a. Insecticide Sprayer. No specific preflight
relieve a vacuum which may have formed in a cold fuel
starting procedures are required for the insecticide
tank.
sprayer. However, the preflight check list of paragraph
(2) Set ignition switch (24) to ON.
21, step a must be performed. Per form any preventive
(3) If engine is cold, pull choke button (20) outward. If
maintenance checks and service functions found
engine is warm, little or no choking should be needed.
necessary
as
listed
in
2-2
