Piuma Almerico

Author preliminary remark

Piuma Project is the name for a series of ultralight motorgliders starting in 1988 (3 single seat and 3 dual seat). Piuma Almerico is the result of many improvements to the Piuma Twin Evoluzione. These many improvements, 5 years of work and pleasure (this is my hobby), led to completely new drawings and a new project.

After the decision to revise the fuselage to reduce the cross section, some other important modifications were carried out, like increasing the wing span and a wing profile more suitable for gliders. These modifications increased the L/D to 26, not bad for a side by side ULM motorglider built from plans.

The Almerico construction is not completed, but the 25 drawing plans and the Construction Book in English and the Project Book (in Italian only at present), a DVD with the CAD drawings for water cutting all the plain metal parts and a DVD with 3200 photos ( many of the Almerico construction), allow one to start construction of a very efficient and inexpensive motor glider.

Twin Almerico project information

The wings are strut supported and the engine is a pusher. The elevators and fin/rudder are similar (but not identical) to the Piuma Twin Evolution. The landing gear is now elliptical, built with some thin Ash layers, bonded with fiberglass and epoxy. Strong, light and aerodynamic. A retractable landing gear is also possible in the drawings.

The front of the fuselage is quite low, to improve the sight line. The new instrument panel is similar to the glider panel.

The fuselage is more aerodynamic than the Piuma Twin Evolution. Less height, but a little wider. The lower/aft part is semicircular, which is clearer in the drawings.

The seats are semi-recumbent, very comfortable for long cruising.

The light frames more than adequately support the struts, landing gear, seats, engine and all the metals parts (control stick, electric motor for the flaps, etc.) and the flight loads.

The engine in the drawings is the 4 stroke HKS700 – 60 HP; all the parts (muffler and exaust manifold, oil tank, oil coolers, oil lines, fittings) are in the drawings for this engine.

A rocket parachute is possible and 4 special bolts are planned in the frame n. 10 (the same for the struts, landing gear and wings).

It is possible to fly solo, but it is necessary to put some ballast in the nose. The space for the ballast is indicated in the drawings.

The wing shape is similar to the Piuma Twin Evolution, but incorporates many improvements:
  • The wing profile, wing chord and winglet are now more similar to a glider: FX 61-168 from the fuselage to where the taper begins and FX 60-126-1 for the tapered part, twisted 3 deg negative; the maximum rib chord is 1150mm, increasing the aspect ratio to 15.4. The new winglet increases the efficiency at low speed. The wings are covered with 45deg birch ply. Little styrofoam pieces (6 or 10mm) are added to the wood ribs to increase their stiffness.
  • The air brakes are moved further aft to reduce the need to adjust trim when activated. The drawings show a new mechanism, which is more efficient and less stressful.
  • The ailerons are operated by push rods, with the hinge line in the center of the aileron, not the top.
  • The little slotted flaps, operated by 2 push rods (not 3), are very effective.

Technical information

Wing Span
Wing Area
Empty Weight
Gross Weight
Fuel Capacity
HP/HP (range)
Top speed
Stall clean
Stall full flaps
L/D max
Aspect ratio
Min. Sink rate (56 mph)
Load factors (breaking)
Load factors (security coeff. 2)
Bldg Time (man hours)
43 ft.
122 sq.ft.
21.3 ft.
6 ft.
600 lbs.
1000 lbs.
12 gal
60 (50/60)
112 mph.
110 mph.
90 mph.
44 mph.
38 mph.
200 ft/min.
+ 8 -2.2
+ 4 -1.1
500 ft.
500 ft.

Construction plans

The Construction Plans are composed of 25 drawings, in English, the Construction Book, in English, (more than 50 pages with 97 photos and drawings explaining the construction), and a complete materials list. There is also detailed information about the wood, birch plywood, glue, aluminum alloy, electric schematics, both general and for electric flaps and trim operation.

The Project book included is only in Italian, at the moment. There are a lot of photos, drawings, graphics and lists. The calculations are easy to understand. Here you can find the Lift, Drag, Moment, VNE, L/D, etc and the structural calculations of the wing and other parts.

Also enclosed is a DVD with 3200 photos (many of the construction of the Almerico) and a DVD with CAD drawings to water cut all the plain metal parts.

The tail boom in Aluminum 6005-T16 is available: diameter 127mm - thickness 1.5mm - length 5.2m. You need 1 tube + ½ tube more. Shipping from Italy is very expensive. However, all the details are in the Construction Book to enable purchasing locally a similar tube.

The material cost, without engine and instruments, but with all the metal parts built, could be about 4,500 Euro, if the metal parts are made from the builder; for the 4-stroke engine HKS700, accessories, instruments and engine mount more propeller DUC Inconel (carbon fiber and ground adjustable) can be expected further 12,000 Euro for the ultimate in reliability and lower power consumption (6-8 liters / hour to 130/145 Km / h). Obviously with a Rotax 503 used, the cost for the operation is reduced to less than a third of this figure.

Construction time is about 1200 hours, plus time to fabricate metal parts.