SERVICE MANUAL & ICA
10000 AMPHIBIAN FLOATS ON AIR TRACTOR AT-802A
Page 12
Revision U
P/N 1002545
On water, the aircraft may be towed with a rope bridle arrangement from these lugs.
A lifting apparatus that will pick the aircraft up by 4 points will facilitate lifting of the entire aircraft on floats from a
ceiling hoist. Two points are provided on aft cockpit sides. Two points are the engine mount at the firewall on each
side. A lifting beam that will pick up all four points is available at Wipaire Parts Dept.
1.3 AMPHIBIAN LANDING GEAR SYSTEM
The landing gear incorporated within the amphibious floats on this airplane is retractable, quadricycle type with
two swiveling nose (or bow) wheels and four (4) (two (2) sets of dual) main wheels. Air-oil shock struts on the two
main landing gear assemblies provide shock absorption.
The main landing gear has dual 8:50 x 10 8-ply tires and the nose landing gear has one 6:00 x 6 8-ply tire. The
gear system is hydraulically actuated and driven by two hydraulic pumps. Brakes are hydraulic and have a caliper
on each main wheel for a total of four brakes.
Steering on land is accomplished by differential braking. The nose wheels are full castering.
Landing gear extension and retraction is accomplished by two (2) electrically-driven hydraulic pumps and four
(4) hydraulic actuators (one (1) for each gear). The hydraulic pumps are located in fuselage aft of cockpit and the
hydraulic actuators are located adjacent to each gear. Hydraulic system fluid level should be checked periodically
by viewing the sight glass for fluid level in the upper one-third of the range. If fluid is low, fill with MIL-H-5606 or
equivalent. Filter screens are installed on each pickup tube inside of hydraulic reservoirs and there are also 3
external 10 micron filters as well. Clean filter screens and elements every 100 hours.
Per Service Letter 103, a Spin-on Type filter assembly with a Baldwin Filter has been incorporated to facilitate
additional filtering of the hydraulic system. Replace Baldwin filter if pop out gage has been released indicating
bypass has been activated due to clogged filter or at time of annual inspection.
Landing gear operation is initiated by movement of the landing gear handle. When the handle is repositioned,
hydraulic pressure in the system will drop and pressure switches will automatically turn on the hydraulic
pump motors to maintain operating pressure in the system. When the gear cycle is completed, the pump will
automatically shut off. If the pressure in the system drops to a preset value, the pressure switches turn the pump
motors back on and build up the pressure to the limit again. Eight (8) position-indicator lights four (4) gear UP and
four (4) gear DOWN are provided to show landing gear position. Two (2) additional indicator lights show when the
landing gear pump motors are operating.
1.3.1 LANDING GEAR HANDLE
The landing gear handle controls a hydraulic selector valve within the control unit on the left-hand side of cockpit
by fuel shut-off handle and has two (2) positions (UP and DOWN LAND) which give a mechanical indication of
the gear position selected. From either position, the handle must be pulled out to clear a detent before it can be
repositioned.
