Author: D. Pruss
Edition: Model Aviation - 1981/08
Page Numbers: 38, 39
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Radio Control: Soaring

Dan Pruss

Toledo — Otto Heithecker returns

Otto Heithecker is back. For contest-goers of the early 1970s whose trophy racks show few first-place awards, the name Otto — and his Challenger — is instantly familiar. He swept the East Coast Soaring Society contests in 1972 and 1973, was ECSS champion those years, then moved up to the National Soaring Society in 1974. That year he was NSS Grand Champion and at the SOAR Nats beat roughly 160 others to take the silver cup. The Challenger was the plane to beat; plans were available then and still are today, and many fliers built and flew the model. For most of us, the Heithecker/Challenger combination was unbeatable.

Otto took a sabbatical from modeling for about five years to pursue full‑scale soaring. He sold his sailplane last year and the itch to build returned. Hearing renewed interest in cross‑country flying and racing, he promptly picked up where he left off.

The Whirlwind

Just before his full‑scale years Otto had designed an 80‑in. flying wing. This past winter he built a much larger version that spans 145 in. and he calls it the Whirlwind. Specifications and features:

  • Wingspan: 145 in.
  • Area: 1,828 sq. in.
  • Weight: 105 oz.
  • Controls/features: elevons, spoilers, flaps, releasable tow hook and retractable tow‑hook door
  • Construction: traditional built‑up balsa, MonoKote covered — no fancy molds or exotic materials

Otto entered the Whirlwind in SOAR's Great Race VI and took first place at Toledo.

Contest highlights

  • 1st place: Otto Heithecker — Whirlwind
  • 2nd place: Ken Bates — updated Merlyn (an LSF Level V original, later optimized for cross‑country)
  • Ken also won first place in the Best MonoKote category for his finish
  • Notable entries: Jerry Mrlik and Dave Corven
  • Dave Corven entered an original FAI design called the Desperado (more details to follow)
  • Jerry Mrlik entered an enlarged version of his FAI plane with a 14½‑ft. wingspan and area at the FAI limits

Jerry Mrlik's design details

Mrlik kept the sleek pod‑and‑boom theme of his FAI design. The outward appearance hides an ingenious internal layout:

  • Large C‑cells occupy the pod with virtually no room for anything else
  • Receiver and servos are mounted in large wing fillets to solve space constraints
  • Thin cables and tubes run down the boom for elevator and rudder control
  • Breaks down into six major components for transport

It’s an engineering masterpiece aimed at cross‑country performance.

What to see at the exhibitors' booths

If you’re wondering where to spend your modeling dollars, here are some highlights from Toledo:

  • Airtronics
  • Sagitta line:
  • 600 version: 78 in. wingspan — aimed at Two‑Meter fliers
  • 900 version: suitable for FAI and various AMA contests
  • 2100 version: about 14 ft.+ wingspan with ~2,100 sq. in. wing area; a cross‑country bird (2100 is direct from Airtronics; 900 and 600 through dealers)
  • Aviomodelli
  • Italian importer offering prefab models up to 4 m span
  • Fiberglass fuselages with obeche‑covered wings and tail parts
  • Line to be handled by The Sailplane Factory
  • Graupner
  • Includes a scale Mini‑Nimbus with foam wings sheeted with balsa, epoxy‑molded fuselage, molded spoilers and quality fittings
  • New T‑tail versions and upgraded epoxy‑molded fuselages (improved over old ABS designs)
  • Top‑quality kits throughout
  • Hobby Lobby (handling the Carrera line)
  • Models include ASW‑17, Nimbus, SB‑10, a slope aerobatic Sagitta, and two attention‑getters: Draco and Mistral
  • Draco:
  • 2001: 98½ in. wingspan
  • 3001: 126 in. wingspan; wing transitions from FX63‑126 at the root to FX63‑100 at the tip (balsa‑covered foam wings with polyhedral preformed)
  • Mistral:
  • 14 ft. 7¼ in. span
  • Spoilers, ailerons (which double as flaps), rudder and flying stab
  • Mechanical mixing allows aileron/flap camber changes
  • Fuselages in the line are molded by Ferran
  • House of Balsa
  • Affordable Two‑Meter planes; a low‑cost entry point (two‑channel radio + Two‑Meter bird is one of the least expensive ways to start)
  • Sailplane Factory
  • Source for hard‑to‑find sailplane items and accessories
  • Catalog updated for Toledo and includes the Aviomodelli line

Final notes

Toledo was a better show this year than last from a modeler’s point of view. Exhibitor numbers were limited to allow more aisle room, and the variety of new kits and well‑engineered contest entries made it a good show.

Dan Pruss Rt. 2, Box 49D, Plainfield, IL 60544

Transcribed from original scans by AI. Minor OCR errors may remain.