Mystery Man (oz4606)

 

Mystery Man (oz4606) by Elbert J Weathers 1939 - plan thumbnail

About this Plan

Mystery Man. Free flight gas model. Published in Air Trails in June and July of 1939.

Quote: "The Mystery Man, by Elbert J Wethers. Part 1.

THIS gas model is one which has taken three and one half months of steady work to produce, from the drawing board to the first test hop. The idea of the ship lifting from the 'take-off gear' was the basic one around which the design was produced. This device has enabled the writer to build a one-wheel landing-gear ship which, due to its general design resembles greatly a sail-plane, especially when soaring on the glide.

The fact that this idea has shown a loophole in NAA rules in regard to 'dropping parts in flight' has come about since its completion, and its designer had no intention whatever of attempting to sneak around this rule in developing it. His main thought was that several one-wheel jobs, with the landing gear or single wheel resting in fuselage bottom (sailplane style), had all employed complex mechanism, at least to some degree, to retract the wheel after the take-off. Therefore, as simplicity is the sound answer to anything and the most practical, why shouldn't the model lift from a dolly on the take-off, and thus eliminate all retracting mechanism?

This feature allows the drag from the landing gear to be minimized, and improves greatly the frontal resistance as compared with even the more common type of one-wheel landing gear, that of the wheel being below the fuselage housed in a streamlined 'leg,' which is of course necessary for propeller clearance. The model presented here also supports itself on the take-off, which cannot be claimed for ordinary one-wheel, landing-gear jobs.

Another problem which had to be overcome was the proper distribution of weight of the take-off dolly as compared with the center of lift of the wing. The dolly in the accompanying plans is the third one to be designed, and allows the plane to take off without any danger of ground-looping or snapping. It operates purely by laws of gravity, and as can be seen in the photos never leaves the ground, being pitched forward to fall flat by the fast-moving plane. The dolly bounces somewhat because of the rubber tires, when settling flat. Therefore, the builder making this ship should conform to the plans in every respect.

The fact that the ship was to be flying under power without the usual stabilizing unit of a conventional-type landing gear underneath, involved precise calculation with reference to the center of gravity, center of lateral area, and center of pressure, and their relation to each other. The CG is located just below the top main longeron of the fuselage frame, or just below the side cabin windows. C of LA is just behind in proper relation and the combination of the high CG and CP has created a model which climbs under power without being in a dangerous vertical bank - as is the case with most retracted-wheel ships - at any time, and which cannot possibly spiral-dive under power, as the flight attitude of the original Mystery Man shows that it is very remote from this well-known danger.

The ship has a spectacular rate of climb, going up like a left-hand corkscrew, and having plenty of altitude after a thirty-second motor run. The glide is very flat, and due to the gulled wing and upturned wing tips, together with the sailplane-type landing gear, the model possesses all the characteristics of a sailplane when gliding, flying in lazy circles and soaring on the slightest of thermals. When it comes in for the landing, it is so flat that on smooth ground the ship doesn't even bounce, and not until it has rolled to practically a standstill does either wing tip drop to the ground on its skid. The model does not show any tendency to ground loop when landing.

The original has been designed to have a perfectly flat glide, with its neutral setting of stabilizer, wing, and also line of thrust.

The motor used is a Brown Jr Model B, although similar engines of the same horse-power rating can be adapted to the motor bed. The ship can be flown on one-sixth horsepower, although the rate of climb will obviously be cut down..."

Update 25/04/2014: Replaced this plan with a full-size version on 2 large sheets, thanks to JJ.

Supplementary file notes

Scan of the original article pages and drawings, as printed 1939.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction

Mystery Man (oz4606) by Elbert J Weathers 1939 - model pic

Datafile:

Mystery Man (oz4606) by Elbert J Weathers 1939 - pic 003.jpg
003.jpg
Mystery Man (oz4606) by Elbert J Weathers 1939 - pic 004.jpg
004.jpg
Mystery Man (oz4606) by Elbert J Weathers 1939 - pic 005.jpg
005.jpg
Mystery Man (oz4606) by Elbert J Weathers 1939 - pic 006.jpg
006.jpg

Do you have a photo you'd like to submit for this page? Then email admin@outerzone.co.uk

User comments

No comments yet for this plan. Got something to say about this one?
Add a comment

 

 
 

Download File(s):
  • Mystery Man (oz4606)
  • Plan File Filesize: 1193KB Filename: Mystery_Man_1939_oz4606.pdf
  • Supplement Filesize: 1409KB Filename: Mystery_Man_1939_oz4606_article_A.pdf
  • Supplement Filesize: 674KB Filename: Mystery_Man_1939_oz4606_article_B.pdf
  • Supplement Filesize: 592KB Filename: Mystery_Man_1939_oz4606_original_drawings.pdf
  • help with downloads
 

Notes

* Credit field

The Credit field in the Outerzone database is designed to recognise and credit the hard work done in scanning and digitally cleaning these vintage and old timer model aircraft plans to get them into a usable format. Currently, it is also used to credit people simply for uploading the plan to a forum on the internet. Which is not quite the same thing. This will change soon. Probably.

Scaling

This model plan (like all plans on Outerzone) is supposedly scaled correctly and supposedly will print out nicely at the right size. But that doesn't always happen. If you are about to start building a model plane using this free plan, you are strongly advised to check the scaling very, very carefully before cutting any balsa wood.

 

Terms of Use

© Outerzone, 2011-2024.

All content is free to download for personal use.

For non-personal use and/or publication: plans, photos, excerpts, links etc may be used, provided that full and clear credit is given to Outerzone with appropriate and specific direction to the original content i.e. a direct hyperlink back to the Outerzone source page.

Unauthorized use and/or duplication of this material without express and written permission from this site's owner is strictly prohibited. If we discover that content is being stolen, we will consider filing a formal DMCA notice.