Avenger (oz7661)


Avenger (oz7661) by Bill Grundy 1971 - plan thumbnail

About this Plan

Avenger. Aerobatic slope soarer for 2 function radio.

Quote: "A novel 'Fighter' type soarer that will start a new trend on the slopes this year! Avenger by Bill Grundy.

ARE you hooked on slope soaring, but looking around for something different? Something fast - exciting to fly! (Sounds like a TV advert) - then the Avenger fills the bill.

One afternoon clubmate John Ralph and I were chasing each other up and down the local ridge (very exhausting), when John suggested it would be a great idea if we were to have two or three fighter type models. As he was always belting me out of the sky in mid-airs (I am losing three-nil), I agreed that the models may as well look like fighters. The other soaring types in our club agreed that it was an exciting idea, too, but no one wanted to make a start. Rather than let such a scintillating idea fade away, I set about designing such a model. It was to have rakish fighter-like lines, and I thought a T-tail would give it that extra something, too.

The result turned out to be a one-piece model of very purposeful and striking appearance (even if I do say so myself) which, besides being fast enough for any pylon race, is highly manoeuvrable and quite acrobatic. The model uses ailerons and elevator, for compactness however, so it will not perform those manoeuvres which normally require rudder, unless you are particularly clever, or use some form of telekinesis.

My own Avenger has been strength-tested several times, when it plunged into the ridge at all angles, due to persistent radio trouble, which I have since cured (I dropped the receiver into the dustbin). I chose the well-tried Eppler 374 wing section because of its wide speed range, the T-tail to keep that back-end clean, and the all-flying tailplane, not for any aerodynamic reasons, but because it is neater and easier to install than elevators, on a T-tail model. The fuselage profile is also Eppler - it's a low-drag section, so why not a low drag fuselage?

Construction. Quite an advanced model, flying-wise, this is not a beginner's project from the constructional point of view either, though it will be found quite plain sailing for the bloke with a few average models to his credit. This being so, I am not going to go into copious detail on the construction. Have a good study of the plan first and, if there are too many things, you cannot follow, then you should put off building this model until you have built a few more run-of-the-mill ones. Some general constructional pointers are all that most average modellers will need, so here they are:

Start with the wing as it is a necessary part (for finishing the fuselage, I mean). All the ribs are shown individually on the plan, but you can use the sandwich method if you prefer it. Build up the wing using spruce spars, which are doubled up at the centre and webbed with in. sheet. After fitting the tube-and-cable aileron linkage and shaping the leading edge, fit the bottom sheeting (I use Evo-stik), trimming off level with the leading edge. Repeat with top sheeting, fit cap-strips and sand to shape before fitting the fuselage.

Having cut out the sides and all formers for the fuselage, wet the outsides of the sides (if you see what I mean) and glue them to the formers with PVA adhesive, bind with Sellotape and leave overnight to dry. In the meantime, start on the fin, building this over the plan, fitting one end of the nylon control linkage tube to it and gluing on the 1/32 in, ply side pieces..."

Direct submission to Outerzone.

Update 02/05/2016: article pages, text & pics added, thanks to RFJ.

Supplementary file notes

Article pages, text & pics.


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

Avenger (oz7661) by Bill Grundy 1971 - model pic

  • (oz7661)
    by Bill Grundy
    from Radio Modeller (ref:76)
    May 1971 
    50in span
    Glider R/C
    clean :)
    all formers complete :)
    got article :)
  • Submitted: 21/04/2016
    Filesize: 408KB
    Format: • PDFbitmap
    Credit*: AugustaWest
    Downloads: 2351

Avenger (oz7661) by Bill Grundy 1971 - pic 003.jpg

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

User comments

Superb model I built in 1972, it has resided in my loft since 1974 and I have just brought it out as I have returned to R/C flying. Here's hoping I don't wreck it first time out. The only weak spot I found was the tail/fin mounting which I see I shall have to repair before flying, ply discs on either side should suffice.
George McCree - 04/06/2020
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, 2011-2024.

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.