Trainer 40 ARF (oz12190)


Trainer 40 ARF (oz12190) by Marshall Kay 2020 - plan thumbnail

About this Plan

Trainer 40 ARF. Radio control sport trainer model. Wingspan 60 in, wing area 660 sq in. For .40 2-stroke engines.

Discontinued ARF kit from Tower Hobbies.

Quote: "Attached are plans for a popular trainer offered by Tower Hobbies that is now discontinued. Several friends own this trainer and some are in need of repair so I reverse-engineered a plan that can be used to create replacement wings, fuselage, or stabilizers. If you are starting from scratch you can build a grounds-up model by ordering a short kit from the Balsa Workbench see

The plan was created by measuring all the parts from a new unassembled ARF kit found on eBay. Some minor changes to the internal construction were made to simplify assembly or because the covering blocked clear visibility to the exact dimensions of the part, but the outer dimensions and flying characteristics were not altered.

The assembly manual can be found on the web and may be useful but I think most any builder even beginners will be able to construct the model. I am starting construction and will add photos as they become available."

Direct submission to Outerzone.

See supplement file for full instruction manual (24 pages), found online (in 'discontinued' section) at:

Quote: "Tower Hobbies Trainer 40 ARF. Almost Ready-To-fly Radio Controlled Model Airplane. Assembly Instructions.

Congratulations! You’re about to build in a few days what took pioneers years - a powered machine that flies. Specially created for you and other first-time radio control modelers, the Tower Hobbies Tower Trainer 40 ARF offers nearly all the excitement of piloting a real airplane - and develops skills that will take you anywhere you want in your new hobby.

Accessories Required to Complete our Tower Trainer 40:
4-Channel Radio With 4 Servos
Engine; (See Engine Selection)
Spare Glow Plugs (Tower R/C Long – TOWG1001)
Medium Fuel Tubing (GPMQ4131, 3 ft)
1/4 in Latex Foam Rubber Padding (HCAQ1000)
1/16 Foam Wing Seating Tape (GPMQ4422)
#64 Rubber Bands (TOWQ1220)
Screw-Lock Pushrod Connectors (GPMQ3870)
Silicone Sealer

Engine Selection:
A quality brand .40-size engine will be needed. Also a prop will be
required for the engine (follow the manufacturer’s recommendations
for appropriate sizes). We recommend the Top Flite Power Point
brand of props. We recommend the following engines:
Tower Hobbies .40 ABC
OS .40 LA
OS .40 FX
SuperTigre® GS-40

We are so confident that the Tower Trainer 40 ARF is the best almost-ready-to-fly trainer available that we make this guarantee. You will successfully learn how to fly with the Tower Trainer or we will replace it with your choice of another trainer of up to equal value. All we ask is that you learn under the supervision of a qualified, club-designated instructor, follow normal safety precautions, fly at an AMA-chartered club field and construct the kit as outlined in this instruction manual.

Wing Assembly:

Draw a centerline on both sides of the plywood wing joiner as shown.

Locate the two 3/8 in square x 1-11/16 (9.5mm square x 43mm) aileron servo tray mounting blocks. Mark a centerline on the blocks. Using the wing joiner as a guide, mark the wing dihedral angle on both of the aileron mounting blocks. Set the blocks aside for use in later steps.

Using a flat sanding block or similar tool and 120-grit sandpaper, sand the wing roots so they will fit together without any gaps. Do not sand too much or the dihedral angle could change..."

Supplementary file notes



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Trainer 40 ARF (oz12190) by Marshall Kay 2020 - model pic

  • (oz12190)
    Trainer 40 ARF
    by Marshall Kay
    from Tower Hobbies
    60in span
    IC R/C Cabin Kit
    clean :)
    all formers complete :)
  • Submitted: 08/05/2020
    Filesize: 1127KB
    Format: • PDFvector
    Credit*: MarshallKay
    Downloads: 2932

Trainer 40 ARF (oz12190) by Marshall Kay 2020 - pic 003.jpg
Trainer 40 ARF (oz12190) by Marshall Kay 2020 - pic 004.jpg

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