Monster (oz12884)


Monster (oz12884) by Charles Mackey from Flying Models  1962 - plan thumbnail

About this Plan

Monster. Control line delta stunt model, for Fox .35 engine.

Quote: "The Monster. Intriguing Delta-Stunt by Charles A Mackey.

Tired of slack lines? New stunt concept drastically offsets engine, passes thrustline through center of drag and CG.

This ship should appeal to flyers who like to be different, are tired of slack lines, want to fly slow or those who drive a compact car.

The design was brought about to incorporate a new idea about line tension. It might be wise to discuss the various methods of keeping a stunt ship tight against the ends of the lines. First of all, let's divide the tension into categories. The first we'll call natural, which is actually centrifugal force. The other, we'll call design which will cover the methods built into the airplane. The natural pull will be governed by three things, the length of lines, the weight of the airplane, and the speed it flies. There is a formula to figure out how many pounds pull your ship will give, but this would be of little value, because it doesn't take into consideration the design tension.

It will help us better understand the problem if we understand the values of these three things that affect the natural tension. If we were bothered lok by slack lines of 70 ft we could shorten the lines to 35 ft and we would double the line tension.

Another way to double the line tension would be to double the weight of the airplane. Don't run out and fill your stuntship full of lead because we still have to contend with wing loading for maneuverability. Now it's easy to see the advantage of the larger ships, the added weight gives line tension and the larger wing maintains the same loading as the smaller ships.

The next and most important factor is the speed of the airplane. We might assume that if we double the speed of the airplane, we would double the line tension, but it doesn't work that way. When we double the speed, the line tension increases four times. That's why the easiest way to improve line tension is to fly a little fatster. The trend seems to be toward slower flying and unfortunately, the rule works in reverse. We get into trouble when we try to slow up a ship that was designed for faster flying. All we can learn from the natural forces or centrifugal force is that the larger design shows some advantages, but not enough to satisfy our requirements. Now we'll have to get into design tension.

We imagine this will lead to some hot discussions, but here we go. All the design features that improve line tension can be divided into two classes. Let's call them 'lift' and 'motor'. (We'll ignore rudder offset because it's practically useless.)

The 'lift' category refers to anything that will make the inside wing lift more than the outside, putting the ship in a slight bank in order turn it out against the lines. This would include tip weight, which only changes the CG to give more lift to the inside wing. It would also increasing the the area of the inside flap, the weighted flap feature..."

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Monster (oz12884) by Charles Mackey from Flying Models  1962 - model pic

  • (oz12884)
    by Charles Mackey
    from Flying Models
    February 1962 
    39in span
    IC C/L
    all formers complete :)
    got article :)
  • Submitted: 02/03/2021
    Filesize: 540KB
    Format: • PDFbitmap
    Credit*: JohnLaycock

Monster (oz12884) by Charles Mackey from Flying Models  1962 - pic 003.jpg

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