Courtesan (oz294)

 

Courtesan (oz294) by Vic Smeed 1988 - plan thumbnail

About this Plan

Vic Smeed design, free flight cabin model.

Originally designed in the 1950s, this is the plan as published in Aeromodeller Oct 1988.

Update 24/6/2024: Added article, thanks to rocketpilot.

Quote: "Courtesan. Pretty and perky - Vic Smeed's 38in charmer from the early 1950s. A beauty from the past.

THIS LITTLE model was designed at the request of the late Charlie Ashby, a fellow-member of the Canterbury Pilgrims MFC, who asked for something like a Tomboy (oz285) but with a few more curves. One of the photographs shows Charlie's model on its first outing in, from memory, late 1953. This was the only model built to the design, as far as is known; the original drawing remained in a drawer with several others until five or six years ago, when they were all dumped, due to a misunderstanding by a colleague.

The photograph surfaced during a discussion on the Irvine Mills .75 when, as a consequence, the plan was redrawn. At least four further models have since been constructed. Some of these will probably have caused confusion at the Old Warden Vintage Weekend (yet to come as these notes are written) but judging from interest already shown in the model it is probable that a number of people will be keen to obtain plans.

Rudder-only radio days: At the time of the original design, single-channel (usually rudder-only) radio was the normal form of radio control and it was thought that the ideal rudder-only model should be able to make one to one-and-a-half complete turns and then drop its nose into a spiral dive. When sufficient speed had been built up, a touch of opposite rudder would straighten the dive and the excess speed would produce a loop. If the speed was judged right, a touch of rudder at the top of the loop would produce a half-roll a 'roll of the top' to the RAF or an 'Immelman' to US fliers. If a full loop was carried out, excess speed would start a second loop and a touch of rudder at the correct moment was needed to turn the model out of a potential stall.

The original Courtesan was not flown under radio as equipment was, on the whole, rather bulky and heavy for this size of model, but it did have the characteristic of making one-and-a-half turns before dropping into a fast-accelerating spiral. The model lends itself to rudder assist with average modern gear; there is plenty of room for two or even three functions with micro servos. Observant free-flight readers will already have concluded that very tight turns are best avoided; under power, circles of not much less than 100ft. (30m) diameter are recommended.

This is one of the rare occasions when the designer has not himself built the model, but our trim intention would be wide right-hand climbing circles achieved with just enough sidethrust to offset torque-induced left turn and produce a hint of right turn, plus about 20 deg. of right rudder trim tab. This would produce similar-size circles to the right on both power and glide, remembering that the tab is slightly less effective without the slipstream; hence the faintly right sidethrust. Power circles to the left with the average sport model are likely to result in a much slower climb, though perhaps such a generalisation is slightly dangerous!

Constructionally the model is straightforward. There is a little extra work in the laminated wing and tail tips but the increase in strength of warp resistance is well worth having. For further comment perhaps it is as well to hand over to one of the builders who has constructed the model recently.

Alec Gee reports: Everything about Courtesan is traditional, including the construction about which little need be said, so easily and enjoyably does it all go together. There are one or two points worth noting, however, and one of these concerns the wing leading edge. Optional flat faced or notched ribs are shown on the drawing for use with 1/4 x 3/8 shaped LE stock or 1/4 in square LE (is probably the better choice). Make sure you decide which before cutting the ribs.

Top and bottom spars require cracking carefully at ribs W3 to meet the wing tips; you'll need to eyeball these, packing up the tip components to obtain a smooth sweep from trailing edge to leading edge while the wing panel is pinned to the board.

The fuselage is a basic 3/16 square box frame; the two sides constructed one on top of the other, for accuracy, over the plan.

Choose hard balsa for the top and bottom longerons (the latter will require steaming to take up the curve) and select medium wood for all the rest. Pretty stringered rear turtledeck uses 3/32 x 3/16 strips and, as is always the case with design features of this sort, it's wise to leave former notching until you actually come to this stage and plot the notch positions by letting the strip balsa find its own natural curve from the cabin area to the rear of the fuselage.

Flying: What can we say? Medium power gives stately performance on calm days; rev up a bit for livelier cirucits, perhaps with a touch of down thrust to keep things safe. Courtesan is every inch a lady - now aren't you tempted, just a bit? "

Supplementary file notes

Article.

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

Courtesan (oz294) by Vic Smeed 1988 - model pic

Datafile:

Courtesan (oz294) by Vic Smeed 1988 - pic 003.jpg
003.jpg
Courtesan (oz294) by Vic Smeed 1988 - pic 004.jpg
004.jpg
Courtesan (oz294) by Vic Smeed 1988 - pic 005.jpg
005.jpg
Courtesan (oz294) by Vic Smeed 1988 - pic 006.jpg
006.jpg
Courtesan (oz294) by Vic Smeed 1988 - pic 007.jpg
007.jpg

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

User comments

Last year I built the Sky Skooter. This year my choice fell on Vic Smeed's Courtesan [model photo & more pics 003-006]. I used an electric motor. The aircraft is now ready and has made the first flights and flies excellent. It is very sensitive on the rudder. The aircraft was built for a vintage plane event.
Nico_Steenbergen - 17/07/2019
I built one of these in 2000, still got it although havnt flown it for about 3 years. Nice build, nice looking model, trimming was very easy, fill the Irvine Mills up, start up and let go! recommended
Mike Hollamby - 17/07/2019
Have set the date on this one to Oct 1988, thanks to AaronKV, it seems it was published much later than the 50s. Can anyone send in a scan of the article? Thanks.
SteveWMD - 01/07/2021
Add a comment

 

 
 

Download File(s):
 

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.