Sylph (oz14548)


Sylph (oz14548) by Bill Bowne 2006 - plan thumbnail

About this Plan

Sylph. Radio control sport model, for electric power. Wingspan 44.5 in, wing area 360 sq in.

Direct submission to Outerzone.

Quote: "Mythologically, a sylph is an invisible spirit of the air. My Sylph, whilst not being invisible, is a delightful model to fly; stable, a gentle staller, and very trustworthy. She’s also an easy model to build, with about the only tricky part being making the canopy (explained in an attached article from our club newsletter).

Construction is all wood, with shrink film covering. The mock Hoerner wing tips may help low-speed stability, but even if they don’t, they look cool!

As you can see, I originally used niCAD batteries in the Sylph. I replaced them with a 2S lipo when lipos became available. After I gave the Sylph to a friend, he replaced the inrunner motor with an outrunner and a 3S lipo. That lasted for several years, until he gave the plane to another modeler, who promptly lost it.

Wing: Spruce spars (bass can be substituted) and balsa shear webbing make for a very strong wing. Please, do put the shear webbing, grain vertical, between the spars. A simple sanding tool to level the webbing top with the spars can be made by gluing sandpaper to a strip of spar stock. Please see the attached 'Drooped Tips' article for how to build the wing tips.

Tail Surfaces: Very straightforward, build these up from balsa strips. Sand the rudder and elevator to a taper, leaving them about 1/8 thick at the TE.

Fuselage: A simple balsa, ply and liteply structure, build the sides first, then join them over the completed tailplane (yes, just like an Ugly Stik - I only steal/adopt from the best!). Fit the wing, drilling through F3 for the wing dowel. Pin the wing in place, then flip it over, then drill and tap for the 1/4 x 20 wing bolt. I strongly suggest you use a wing bolt that has a hex (Allen) wrench center, so it’s easier to engage.

If you prefer a simpler setup, leave your Sylph with an open cockpit and tap the bolt plate in the fuselage, instead.

Insulate the wing with plastic sandwich wrap, then build the turtledeck and canopy.

I recommend mixing 10-20% rudder into the ailerons, to help with adverse yaw. For the first flights, balance the model on the front of the spar.

Sylph Stats:
Wing area: 360 in. sq.
Span: 44.5 in.
Weight (with NiCads): 40 oz."

Supplementary file notes

Article (drooped tips).
Article (pop bottle moulding).

CAD file

This plan is available for download in CAD format.


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

Sylph (oz14548) by Bill Bowne 2006 - model pic

  • (oz14548)
    by Bill Bowne
    March 2006 
    44in span
    Electric R/C
    clean :)
    all formers complete :)
    got article :)
  • Submitted: 03/05/2023
    Filesize: 643KB
    Format: • PDFvector • CADfile
    Credit*: BillBowne
    Downloads: 578

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

User comments

It's electric, article states what batteries were used and plans show the installation.
Douglas Babb - 11/05/2023
Got it. Fixed now, thanks.
SteveWMD - 11/05/2023
Add a comment



Download File(s):
  • Sylph (oz14548)
  • Plan File Filesize: 643KB Filename: Sylph_oz14548.pdf
  • Supplement Filesize: 34KB Filename: Sylph_oz14548_article.pdf
  • Supplement Filesize: 490KB Filename:
  • Supplement Filesize: 2121KB Filename: Sylph_oz14548_article_pop_bottle_moulding.pdf
  • CAD Zip Filesize: 123KB Filename:
  • help with downloads


* 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.