Humdinger (oz6199)

About this Plan

Humdinger. Free flight sport model.

Quote: "Humdinger by Ray Booth a really interesting small FF for 1/2a power from MAN."

Direct submission to Outerzone.

Update 06/03/2021: Added article, thanks to MikeFoster.

Quote: "Here's something truly different in Half-A free flight, a ship that gets up and goes like racing plane. And different to build! The Humdinger, by Ray Booth.

FOR some time the designer has had the urge to break away from the more conventional pylon models in an effort to produce an interesting free flight ship with snappy performance but not necessarily long duration, at the same time bearing in mind ease and simplicity of construction and, consequently, repair.

Properly trimmed, Humdinger will reward its builder with consistently zippy flights, with take-offs and landings which will draw murmurs of admiration from spectators. The landings in particular are a dream to watch, as the ship has a rather peculiar characteristic. As the model drops within 1 ft of the ground during its glide approach, the nose rises slightly and the tail drops, resulting in a perfect three-pointer on a fairly smooth surface. This characteristic doubtless stems from the position of the stabilizer in relation to the wing, 'ground effect' causing the wing to 'balloon' and the tail to drop.

Construction of the fuselage is probably a little unorthodox and the following assembly procedure is recommended. Pin down over the full-size plan the 1/8 sq hard-balsa longerons at the top and bottom of the fuselage and, thoroughly cementing all joints, add the 1/4 x 1/8 strips forming part of the under fin, the 3/8 x 1/8 fin and the 1/4 x 1/8 strip which stiffens the stabilizer platform.

Next, cement in place the 1/8 sq spacers between the longerons at each of the former positions, as illustrated in the perspective view on the drawing. The keel diagonals, cut from 1/16 x1/8 strip, can now be fitted into position, completing the center keel 1/8 in thick.

While the keel is still pinned down on the building board, add the half-formers for the port (left) side of the model, insuring that these are true and square with the top and bottom longerons in the plan view. The forward and aft portions of the 1/8 sq side longerons should be cemented to the fuselage side rib before fitting to the half-fuselage assembled on the building board.

When the half-fuselage is completely dry, remove from board and add half-formers for starboard side, followed by other side rib and longeron. The 1/8 x 1/16 flat side braces can now be fitted between F-3 and the TE of the built-in fin. The bottom of the cockpit window has a 1/8 sq diagonal. Fill in the four sides of the fuselage between F-1b and F-2 with 1/32 sheet..."

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