Seamaster

Ken Willard's Wavemaster & Seamaster

The late Ken Willard was a prolific American designer of model aircraft & his Wavemaster Seaplane must be one of his finest creations. This design was only ever produced as a kit, and as far as we know, no plans exist. However he later produced the Seamaster which seems to have corrected some faults in the original Wavemaster design and Seamaster II which again was kitted. All three model are very similar. The kits are no longer available and the companies ceased trading many years ago. The only external difference is in the tailplane location. The Wavemaster tailplane is in the normal position but the Seamaster series have the tailplane on top of the fin, well away from the water surface. Also the Seamasters were much lighter. As a kit, Wavemaster had a moulded fuselage in two halves. If you are considering a flying boat or seaplane you can do a lot worse than this proven iconic design. It has a considerable following in the USA with larger & smaller designs, some with electric power. I have added some links to Seamaster related sites, one even has a video. The plan for Ken Willards Seamaster II is still available as RCM Plan 913. The plan below is widely available from various sources on the Internet but this version has been more or less totally redrawn and is offered as a .pdf file for ease of printing.

Construction

The model is of straightforward construction with an easy to build parallel wing. The most important point is to make 100% sure the hull is watertight with a good waterproof varnish on the inside, done after construction by pouring varnish in through the forward hatch, fully coating the insides, and the letting most of it drain out again. Check for water ingress after EVERY flight. A light skin of Fiberglass on the hull will add weight but should keep the water out. Waterproof bulkheads are a good idea, but DO RETAIN WATER. Small holes at the bottom of bulkheads are a better idea as water can be drained out if required.

Airfoil & Printing Notes

The NACA 2417 specified on the drawing is essentially an NACA 2418 (18%) thinned to 17%. The Software Profili 2 has a facility to compute any NACA foil you may require & to generate leading edges, trailing edges, building tabs, lightening holes & spars as required. These can then be printed out or sent to a CNC machine. See my links page. See also the Selig Site. I have checked the NACA 2417 airfoil shown on the drawing against a very accurate plot and it is as good as perfect.

The .pdf files are quite large so please allow a couple of minutes to download. If you use a print shop specify METRIC and AO paper. The 3 sheets should join to give a full size plan

Co-ordinates for NACA 2417 as a text file. This will need modifying as a Script File (.scr) to run in AutoCad. See my Airfoil Section

Download Seamaster Sheet 1 .pdf file

Download Seamaster Sheet 2.pdf file

Download Seamaster Sheet 3.pdf file

Useful Links to Wavemaster & Seamaster Sites

Ken Willard wrote an article on Remote Piloted Vehicles (RPV's) in the MAP Radio Control Manual No.5 circa 1972. A Wavemaster was used for these experiments and there are a few photo's of the model in action. It is interesting to note that the model was an amphibious version with an undercarriage fitted. In the article he mentions the original model was kitted by King R/C Distributors. (USA) The article was reprinted from American Aircraft Modeller

http://www.maineflyer.net/MyAircraft/MyAircraft.htm Scroll down to the Seamaster Video, 5th model down.

Top Notch Kits in the USA still do a "short" laser cut kit for the Seamaster. Try this link Top Notch Kits USA

Full size detail of a similar Full Size Amphibious Aircraft

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