Senior Telemaster (oz9275)

About this Plan

Senior Telemaster. Radio control sport model. Wingspan 2400mm.

This is the original German version of the Senior Telemaster design, as sold by Alexander Engel KG from 1970 (also later sold by Hobby Lobby from 1973) complete with barn-door ailerons. For the later 1975 version with strip ailerons see RCM Senior Telemaster (oz5044).

Quote: "Senior Telemaster has been developed especially for the fans of big model airplanes, and due to its high inherent stability and docile flight characteristics it facilitates proceeding directly from free-flight sport models to multi R/C flying. All controls and the throttle are provided for actuation. If for some reason the ailerons are not used, the dihedral should be increased from 65 to 130 mm (2-9/16 to 5-1/8 inches) to provide sufficient lateral stability.

Due to its high-lift wing airfoil, the Senior Telemaster is very well suited for special tasks like banner tow, leaflet and parachute dropping, aerial photography, etc., but it is suited for rather simple aerobatic patterns.

Building the Fuselage: Cut sheet 1 of the plan along the dashed line and glue the parts together so you have the complete fuselage views in one piece.

Now drill through the engine bearer bars 9 and glue a M3 (metric thread, about 1/8” diameter) nut under each drilled hole using epoxy. Drill the holes in the formers 12, 14, and 20, which are lead-throughs for the fuel tube, the throttle Bowden cable, and the tail wheel mount, and in former 14 make the cut-out for the tank.

Now assemble formers 15 to 20 and bind and glue the tail wheel mount to the back of former 20.

Assemble both fuselage sides from parts 1 to 6, and bevel the endings according to the top view drawing. Now drill the holes for the mounting dowels. Tack the right fuselage side flat upon the building board and glue on parts 7 to 15. Add parts 7, 9, 11, and 13 of the left fuselage side, insert the tank compartment cap 21 and glue on the left fuselage side.

Subsequently, raise the end of the right fuselage side by 52 mm (2.05”) and in this position, glue the ends of both fuselage halves together. Insert formers 16 to 20 and glue on the nine fuselage bottom pieces 22 and the landing gear rest 23.

When the glue has well settled, the fuselage may be taken off the building board. After this, the upper cap bars 24, the former bracings 25, and the lower cap bars 26 are glued in. Now the landing gear parts 28, 29, and 30 are bound together using binding wire, and glued with epoxy or soldered. Install the main wheels 31 on the main landing gear. Now glue the tail wheel strut 32 into the tail wheel mount and install the tail wheel 33.

Following this, cut (saw) the engine bearer plate 34 appropriate to your engine and drill eight holes, of which the four inner ones have to fit the engine and the four outer ones have to fit the engine bearer bars 9.

Now the fuselage is carefully trimmed (fettled) and all edges, except the wing and tail saddles and the landing gear rest, are well rounded..."

Cleanup by rchopper56.

Added kit instructions translated into English (2011) thanks to Burkhard Erdlenbruch, found online at time.hs-augsburg.de/cgi-bin/dl.pl... (also includes full bill of materials).

Direct submission to Outerzone.

Update 30/6/2024: Added review from RCM, April 1973, thanks to Burkhard.

Quote: "RCM Builds the Senior Telemaster. Product Test by Bill O'Brien.

If there is one thing that Jim Martin at Hobby Lobby International has, it's a sense of humor. Over the past few years we have become somewhat used to his weird ads in the front of our magazine, but we weren't quite ready for the telephone call we received from Jim a couple of months ago. Jim's question was, How would we like to do a review on a high winged model with a one piece 8 ft span wing and an all-up wing loading of less than 9 oz per square foot?"

We replied somewhat to the effect that we'd enjoy such a model about as much as we'd like a hippopotamus living in the kitchen! The trouble was, that Jim wasn't kidding! What followed a few days later was a kit box, the largest we have ever received at RCM. And inside the kit box were all the necessary parts for an aircraft called the Senior Telemaster, manufactured in Germany and imported into the United States by Hobby Lobby International.

To say that the Senior Telemaster is big would be the understatement of the year. This behemoth has a 05" wing span with a 14" chord and a total wing area of 1330 square inches or 9.236 square feet! In addition, the stabilizer is a lifting surface with a 34" span and a 91/2— chord for a total additional lifting area of 320 square inches, bringing the total lifting area of the wing and stabilizer to 1,653 square inches or a grand total of 11.48 square feet!

Our first reaction upon receiving the kit was to hide it under the workbench and, if Jim ever called again, to tell him we hadn't received the kit. After ali, what do you do with a large 'trainer-type' aircraft of this size? Our second thought. and the course of action we subsequently followed, was to pawn the beast off on Bill O'Brien, one of our editors. for his raucous and somewhat sarcastic remarks about the editor's flying ability. Before we did, however, we took a closer look at the contents of the Senior Telemaster kit.

This aircraft design has been around for a number of years in Germany, and has been used to string telephone lines across deep ravines, which task would otherwise require the use of a full-size helicopter. The kit consisted of some of the finest quality balsa wood that we have seen to date. The structure is utter simplicity, and virtually any modeler could follow the construction sequence even without English instructions.

The fuselage is of the lightest weight design we have seen, using excellent engineering techniques to achieve maximum strength and durability at a minimum of weight. As you can probably determine from the photographs of our prototype of the Senior Telemaster virtually any radio, along with your St Bernard, would be lost in the interior of this giant.

Bill O'Brien grudgingly accepted the task of putting the Senior Telemaster together. Within a few days the structure was completed and the photographs accompanying this article were taken. Shortly thereafter the model was ready to fly, completely covered with opaque white and transparent yellow Solarfilm.

Although the model would undoubtedly fly with any engine from a .35 on up, we installed a .60 engine and, just to to make Jim happy, a Hobby Lobby 5 proportional system. The all-up weight of the model was slightly under 6 lbs, which gave us approximately an 8-1/2 oz wing loading! From that point on things began to happen!

We can say, unequivocally, that the Senior Telemaster is one of the most enjoyable aircraft we have ever flown. The ailerons, when used alone, are relatively ineffective on that huge wing, and thus the Telemaster required coordinated turns using both rudder and ailerons in conjunction with the elevator. The take-off run with a .60 is approximately three feet, and from then on in the Senior Telemaster flies like a full size light plane. It is capable of doing most of the maneuvers and could carry any type of payload you wanted to include, such as a movie or still camera and the like.

No matter where the Telemaster was taken, it was an instant hit! One modeler at a local flying field went to sleep under the starboard wing since it was the only shade available, while other modelers complained that a low pass by the Telemaster created a dark shadow on the flying field and made their spot landings difficult to observe.

After a while the reactions of the modelers at any field could be predicted. The first comment would be you've got to be kidding! followed by a short and somewhat sarcastic chuckle. After a demonstration flight, their reaction changed to where can I get one?

That question is easy to answer. The Senior Telemaster is available from Hobby Lobby International, Route 3, Franklin Pike Circle, Brentwood, Tennessee 37027, at a price of $49.95. which is extremely reasonable for an aircraft of this size and a kit of this high quality. We understand that the price may be going up six or seven dollars, but it will still be a bargain. And, if you have any doubts about transporting it, Bill O'Brien has been hauling the Senior Telemaster around in the back of a Pinto Fastback! You won't believe it until you try it.

The Senior Telemaster is an excellent model that was designed to do a specific job. For the sport flyer, it is a model that is easy to fly and can perform some absolutely delightful maneuvers that you'd be hard put to duplicate with a smaller aircraft. You will enjoy building it and you will enjoy flying it. And, because of its light wing loading and easy flying characteristics, it will be an aircraft you'll have around for a long time to come. The Senior Telemaster kit as imported by Hobby Lobby International is Tested, Approved, and Recommended by RCM."

Supplementary file notes

Instructions, 4 pages (de).
Instructions, 14 pages (en).
Review, RCM 1973.

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