Ryan PT-25 (oz942)


Ryan PT-25 (oz942) by Mike Hetherington from Aeromodeller 1946 - plan thumbnail

About this Plan

Ryan PT-25. Indoor Flying Scale RTP (rubber) model from Aeromodeller January 1946. Uses paper construction.

Quote: "This model is a departure from the orthodox method of construction in the fact that it is constructed mainly of thin paper. I remember a few years ago making a couple of low-wing scale type models from paper. These were intended for free flying, as pole flying was in its infancy then. The duration was not high but they flew, which was all I was concerned about at the time. With the coming of the winter months pole flying was introduced to our club (the Doncaster and District MFC), and I was prompted to build up this type of model again specifically for RTP flying. This resulted in the model about to be described.

When first taken down to the club it was received rather dubiously, but when the other fellows saw it flying this cleared away any doubts they had about its capabilities and, in a short time, they had produced quite a collection of paper flying scale models, including Henschel 123, Lightning, Helldiver and Piper Cub, etc.

Practically every type of aeroplane can be reproduced with paper construction. The only difference there is from the normal tissue and balsa type is the slightly angular appearance they present. This is not normally very noticeable and detracts very little (if any) from the general appearance of the machine. How much better is this though than the normal flying scale one sees with the stringers and formers, etc., prominently emphasised by taut tissue? (I am referring now to models whose prototype is covered with a stressed skin.) Where it occurs that the machine is covered with fabric the ribs and stringers, etc., can be imitated by thin lines drawn in indian ink or black dope on the wings and tail, etc., before they are assembled. These lines can be drawn with a mapping pen, although the ideal is, of course, a draughtsman's ruling pen. A pair of sharp scissors will he found useful for cutting out the various pieces of covering, though a razor blade will do just as well.

The author's model was covered in a smooth paper, thinner than foolscap, which can be used if desired, but the finished machine will be heavier than mine and the performance will invariably suffer. Anyway, whatever paper you use see that it has a nice smooth surface as it handles better. All the wood stated on the plan and as used in my machine was balsa, and the amount used is very modest. (A favourable point in these days.) If, however, this is unprocurable, hardwood will do just as well, providing the sizes are decreased slightly so as not to increase the weight unduly..."

Update 15/03/2018: Replaced this plan with a clearer copy (patterned background removed).

Supplementary file notes

Article pages.
Previous scan version.
Alternate plan. Same plan, all parts scaled to fullsize.


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

Ryan PT-25 (oz942) by Mike Hetherington from Aeromodeller 1946 - model pic


  • Ryan_ST | help
    see Wikipedia | search Outerzone

    ScaleType: This (oz942) is a scale plan. Where possible we link scale plans to Wikipedia, using a text string called ScaleType.

    If we got this right, you now have a couple of direct links (above) to 1. see the Wikipedia page, and 2. search Oz for more plans of this type. If we didn't, then see below.

    ScaleType is formed from the last part of the Wikipedia page address, which here is https://en.wikipedia.org/wiki/Ryan_ST
    Wikipedia page addresses may well change over time.
    For more obscure types, there currently will be no Wiki page found. We tag these cases as ScaleType = NotFound. These will change over time.
    Corrections? Use the correction form to tell us the new/better ScaleType link we should be using. Thanks.

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):


* 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, 2011-2021.

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.