Begin-Air Trainer (oz11168)

About this Plan

Begin Air Trainer. Radio control sport trainer model. Designed for HB .25 RC motor.

Note see also Sunrise 2540 (oz14840) for what is essentially a low-wing version of the same design.

Update 29/9/2022: Added kit review from RCM, Feb 1984, thanks to rocketpilot.

Quote: "RCM Product Review: Buzz Waltz R/C Designs Begin-Air Trainer.

We were introduced to the Begin-Air Trainer by a friend who had built and was flying one of these very neat planes. By the way, he is an experienced builder and flier. Once you set eyes on this plane, it is irresistible; we caved in and placed our order post haste. Upon receipt, it was discovered that the kit really was designed for the beginning modeler. It had one of the most complete set of instructions we have seen in a long time.

Because summer plans would take us away from the workshop for a relatively long span of time, it was decided to set forth a task for ourselves. The task would be to build the plane under the same circumstances that a rank beginner would find himself. We were to be away from all the power tools and special purpose tools. We packed the kit in a larger box, included a radio, X-Acto knife and extra blades, a few small hand tools, some glue and sandpaper. We were able to put together a building surface that would accommodate a whole sheet of plans.

The first thing we noticed when we opened the kit was that the plans were rolled, this always elevates the manufacturer in our mind. Nothing in the kit was die-cut, everything was sawed and sanded. For example, the wing ribs were all exactly the same shape, the spar notches exactly the same size and all other balsa parts were just as neat. The hardware and small balsa and ply pieces were enclosed in plastic bags to minimize being scattered all over the box.

Construction: When we unrolled the plans we found four sheets, each of which measured 24 x 43 in. Two of the sheets were the normal set of plans, one featured the tail surfaces and fuselage, the other the wing halves. The other sheets were step-by-step drawings of the fuselage and wing construction. These two sheets were pinned to the wall in the working space for easy referral as most steps in the instructions called out reference to the drawings. We like this unique feature of the kit very much.

The 21 page instruction book, in extra large type, was set up in a step-by-step format. Almost every step referred to the three dimensional drawings on the extra plan set. As each step progressed, the drawings progressed until you have completed a part of the plane. We feel these instructions, together with the drawings, make one of the better instruction manuals we have run into in a long time.

While working on the wing, we ran into the first problem that is going to challenge the beginner. Not only is the top of the leading edge well-rounded, so is the bottom; that is a lot of balsa wood to remove. The normal procedure is to reach into the drawer, remove the small hand plane, and set to peeling away the balsa wood in neat beautiful curls. The plane was back home so we had to settle for using sandpaper. We used 2 x 9 in boards of 1/4 in ply, contact cement and sandpaper to make the finest sanding blocks going. Why 9 in long? That is the width of ordinary sandpaper, just cut a 2 inch strip from the sandpaper, cement it to the board and you can even put a different grade on the reverse side. Be sure to have one board with No. 80 grade sandpaper, that one can hog out balsa almost as fast as a plane. Follow with 100, 120, 240 grits.

The instructions indicated you should glue the shear webbing between the spars. We deviated slightly and glued the sheer webbing to the bottom spar then glued the top spar in place. The webbing was individually cut and sanded to size, all you had to do was cut a tad off the length and they fit perfectly.

Another thing we appreciated was that all the spars and wing sheeting were cut to length; we feel this is much better than having to cut all pieces from 36 in standard stock. The instructions indicate you should bevel the center ribs in accordance with the ply dihedral braces. This is not quite enough to get the 1-3/4 in under each wing tip as called out in the dihedral instructions. If you are going to fly the plane without ailerons, the indicated dihedral is absolutely necessary.

The fuselage was not particularly difficult to construct, however, do not install the last 3 in of the 3/32 sheeting until the very last. We even covered the rest of the fuselage before adding this part. You cannot get to the elevator horn with this sheeting in place. The elevator must be finished, covered and installed, the pushrod hooked up then add the top sheeting, cover, then add fin and rudder..."

Direct submission to Outerzone.

Quote: "Attached, is the kit review for the "Begin-Air Trainer", oz11168. It was in RCM, Feb 1984. I had built two models of the Begin-Air Trainer many years ago, and one is still going strong as a club trainer. Last month, I started out building an electric version (weight reduction) of this wonderful airplane which will have built-up tail surfaces in place of the 'wooden planks'. My fuselage is partially built, and once complete, I will start the wings. The review is spot-on. The airplane is that wonderful to fly.
I do not have the 21-page instruction book that is referenced in the article. However, the plans are more than complete to build the model."

Supplementary file notes

Review.

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