PBY 5-A CATALINA (Wing span 104 inches)

This model is designed with the wheel wells built into the fuselage so that a scale landing gear can be installed, just like the original aircraft. The landing gear kit is scale in operation but not an identical miniture to the full size aircraft. The landing gear is powered by a Robart air cylinder for retraction and extension.

The kit includes a Robart nose gear assembly, machined fittings for the articulating joints, and prebent 3/16" wire struts. The load strut is constructed of 4130 chromoly 3/8" tubing. The oleo struts are Robart and the strut plates are also constructed of 4130 chromoly .050 steel. The landing gear comes mostly prebuilt.

Construction entails some grinding and filing of some of the joints, finish assembly and mounting the retracts and the air cylinder in the wheel well. The fuselage has an access hatch in the nose covered by the clear vacuum formed cockpit and nose gunner turret. The fiberglass halves come prejoined and the waist gunner blister holes are already cut open. The fuselage requires no bulkheads or reinforcing. The pylon is integral.

The kit includes full size plans, vacuum formed cowles, nacells, and wing floats. All wood is included except the covering for the wing. The wing covering is not included because monokote is not the best for a model this big, and there are a lot of different covering processes that can be used. Various people prefer different methods of covering wings so I am letting the builder choose his / her process and select their own materials.

I covered my prototype with 1-1/2 oz fiberglass cloth directly onto the wing foam using 2 coats of epoxy resin. The construction video shows this process. The wing floats are retracted with pneumatic landing gear units. The scale float retracting system is very intricate and difficult to do without adding considerable weight to the aircraft so I have elected to use this system. If a person wanted to invest the time into it, a scale system could by built.

The wing has a semisymetrical air foil. The outer panel come off of the center section just outboard of the engine cowls. A socket made of 1/8" and 1/4" ply telescopes around the main spar. The outer panels are then held on by the functional wing lift struts. The struts utilize a steel wire inside the stream line aluminum lift struts and are attached to the wing and fuselage with sheet metal screws. The nose gear operates in a wet well. It features clamshell doors just like the full scale PBY.

The engines are operated by 2 servos. One servo operates the throttle on both engines and the other servo trims the motor servo left and right to enable in-flight engine synchronizing. The plane flies like a pussycat. It is very stable and responds smartly to all of the control surfaces. Take off run is 100 to 150 feet with very little float pulling due to the slightly modified float design. The design also features the correct factory wing and stab. incidences, greatly improving water and take off performance.

Wing span 104²
Scale 1/12
Area 1270 SQ. IN.
Weight 23 LBS
Length 70²
Engines .60 2-CYCLE - .90 4-CYCLE
Radio 7 Channel - 3 control surfaces + motor servo + motor trim servo + landing gear valve servo + float valve servo

The following parts are included in kit. The number on the left can be found on the coresponding parts.

Balsa
1 balsa block to go on stab for rudder hinge 1X1X1
2 " " " " " " stinger for hinge pin 2X3/4X1
3 1/8" balsa for wheel well flange 3X1/8X36
4 balsa float doors 1/4X15X4
5 leading edge (3) 1/2X1X36
6 trailing edge (3) 3/8X1X36
7 1/16" balsa for wing ends and main joints 1/16X4X36
8 1/4" balsa for pylon filler 4X13X1/4
9 Cowl stands (8) 2X1X1/2
10 stab leading edge 5X8 X36
11 stab tips 2-1/2X7/8X12
12 elevator trailing edge 3/8X3/4X30
13 rudder post block 1X1X1
14 water rudder push rod 3/8 X24 Air rudder wood
15 #5-1/2X2X3-1/8, #6-1/2X1-1/2X3-1/2, #7-1/2X1X2-3/8, #8-1/2X1X2-3/4, #15-9 control horn block-3/4X2x2-1/2, 15A rudder ribs- 1/8X4X14, trailing edge ply-cut from sheet provided
Ply
16 1/8" 9 X 48 for the following parts cockpit bulk heads cockpit floor hatch hatch leveler nose gear top nose chine and splash rail float ribs and top motor servo plates aileron servo mount plates receiver switch mount wing bolt plates
17 main spars wing end panels
18 main spar for center section
19 spar box sides
20 3/8" ply for gear spacer
21 cowl rings
22 tank well sides
23 stab spar
1/4" Ply
24 wing center section main spar stubs
25 LE spar and firewalls
26 for pylon nut plate
27 retract plates
Dowel
28 dowel for lift struts 1" X 10"
29 cockpit hold down screw 1" X 1-1/2"
30 1/4" stab dowel spar 6"
31 1/4" for cockpit rear hold down 1"
32 1/4" retract plate anchor dowels (8) 1-1/8"
33 1/4" wing align dowels (2) 3-1/2"
Sticks
34 3/8 sq. hardwood for lift struts, 7/8"X1/2"X2"
35 hard point mounts in floats 1/2X1/2X5
36 1/4" for top and bottom of main spar box 20"
37 cowl and nacelle mounts 3/8 X8
38 3/8" sq. pine 50" nose gear well flange, aileron servos elevator servo mount, air valve servo mounts rudder servo, load strut lever mounts, motor servos, aileron servo lock pulley,
39 3/4X1X1 pine for aileron horn mounts (2)
Hardware
40 plans
41 cockpit hold down blind nut and machine srcew 6-32X3/4" (1)
42 50 # 2 screws for cowls, nacelles, nyrod mounts, nose gear box top.
43 1/8" water rudder shaft 1" X 1/8"
44 " " " tube Brass
45 22 ga. sheetmetal for water rudder
46 water rudder steering arm
47 3 control horns
48 13 hinges
49 decals (2) large and (2) small
50 acetate for windows
51 strut fairings
52 shutter doors
53 18 ga. steel plate for float mounts 5/8" X 3-1/2"
54 22 ga. steel for float door mounts 1/4" X 1-1/2", 1/4"X 4"
55 Steel elevator horn (1)
56 stream line tubing (2)
57 nylon wing bolts (2)
58 1/4" blind nuts (2)
59 strut wire 3/32" X 36(2)
60 strut eyes (8)
61 strut #6 screws (8)
62 fuselage
63 cowls
64 nacelles
65 blisters
66 cockpit
67 floats
68 wing foam
69 stab foam
70 stab extension foam
71 2 6-32 blind nuts and machine screws for wing retainer
72 Aileron, air valve servo mount blocks (8) 1 X 1 X 3/8
73 9"X 5" piece of fiberglass mat for installing interior parts