The image below shows Holon, designed and built by the Swiss/German LOGO team.
(main team members: Kaufmann, Wick and Wohlfahrt)

The Holon

In principle, tailless model planes and flying wings can be equipped with any airfoil. But if performance is an issue, as it is the case in contest flying, the airfoil should be carefully selected. It is possible to use the same airfoils which are used on high performance F3B models, if their torsion moment is compensated by the appropriate combination of wing sweep and twist. Sweep and twist usually cause a performance loss, which can be minimized, by choosing airfoils with moment coefficients cm c/4 close to zero. More details can be found in the links below.

In the late 1980s, when the LOGO-team approached me with the wish for new airfoils, various airfoils were used for tailless F3B model planes. While the performance of these models was quite good, the high start performance and handling qualities were very poor. This was caused by a rather small maximum lift coefficient and an abrupt stall characteristics of these airfoils. Because the altitude, which is achieved during the high start phase of the flight, is extremely important, the tailless models suffered badly from these airfoil characteristics. A typical, asymmetric wing stall lead to a complete loss of control, resulting in a high speed corkscrew flight path under the full power of the winch, which often resulted in a complete disaster.

The main aims during the design of the MH 40 series and MH 60 series airfoils were:

The following four airfoils were published [1] and have been widely used.

  • MH 60, t/c = 10.08%
  • MH 61, t/c = 10.28%
  • MH 62, t/c = 9.30%
  • MH 64, t/c = 8.61%
  • The following airfoils were never intended for publication, but somehow managed to escape from my test laboratory. All of them seem to work quite well, even at Reynolds numbers below 200'000. The MH 45 also appeared in [2]:

  • MH 44, t/c = 9.66%
  • MH 45, t/c = 9.85%
  • MH 46, t/c = 11.39%
  • MH 49, t/c = 10.50%
  • see also:
    Flying Wings: Airfoil Design and Selection
    Basic Design of Flying Wings

    Last modification of this page: 08.09.03

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