Simoon MkII (oz11145)


Simoon MkII (oz11145) by E Dilley from RCME 1979 - plan thumbnail

About this Plan

Simoon MkII. Radio control sailplane model.

Quote: "SIMOON represents two years research and the results are, to say the least, remarkable. The model offers all that is desirable from a modern slope soarer, a fast, precise, low drag glider coupled with futuristic lines. The quintessence of Simoon is a 20° swept wing which decreases frontal area, and thus drag for a given wing span, whilst ailerons give superb axial control. Tight loops can be effected with less likelihood of stalling the wing, a common fault with many aircraft.

These advantages occur with sweep angles of up to 20° as I have discovered to my cost! Any extreme angle such as 50° has a detrimental effect on both looping and stalling characteristics, resulting in a higher stalling speed, which automatically indicates overall higher flying speeds. Aerobatic manoeuvres require very high speeds demanding much faster thinking and reaction times. Loops become difficult to accomplish without a flick roll at the zenith when the relative airspeed is minimal. I learnt this from a 50° swept wing which preceded Simoon, and on these results I decided to choose a 20° sweep to yield the best all round performance.

On these lines. Simoon was born with a really sporting acrobatic performance. The stalling speed is low, so much so that in a 20 mph wind, Simoon will hover quite happily, and even fly backwards!

So far l have discussed Simoon with a fully symmetrical section, there is also the option of a semi-symmetrical aerofoil which allows the less experienced pilot more time to react in tricky situations. To sum up, the sermi-symmetrical section results in more inherent stability, while still retaining a good acrobatic repertoire. If you decide to be daring, on the other hand, and build Simoon with the fully acrobatic wing, you will certainily have many exciting flying hours!

Building: For ease of construction Irecommend that the building sequence is read through liaising with the plan before building is commenced. PVA white glue was almost exclusively used for strength and lightness.

Start by cutting two fuselage sides from two well matched pieces of 3/16 (4.5mm) sheet. If you build the semi-symmetrical wing, it will be necessary to adjust the wing mount to suit it. For the full length fuselage sides. it is necessary to join two pieces together at the tail end and reinforce with a 1/32 (0.8mm) ply doubler. Pin them together and sand so each is identical in outline. The spruce longerons and triangular pieces can now be added onto each side..."

Scan from KaoruKiyose, cleanup by rchopper56.

Direct submission to Outerzone.

Update 11/05/2019: Added article thanks to RFJ.

Supplementary file notes



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

Simoon MkII (oz11145) by E Dilley from RCME 1979 - model pic

  • (oz11145)
    Simoon MkII
    by E Dilley
    from RCME
    November 1979 
    58in span
    Glider R/C
    all formers complete :)
    got article :)
  • Submitted: 25/04/2019
    Filesize: 697KB
    Format: • PDFbitmap
    Credit*: KaoruKiyose, rchopper56

Do you have a photo you'd like to submit for this page? Then email

User comments

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



Download File(s):


* 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.


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, 2011-2020.

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.