DaSH PA -- Human Powered Airplane Project
Project Information page
In late 2010, we decided to start a for-fun, after hours project to build a human powered airplane. The goal is to do a fun build project, and learn while doing it, while keeping the overall parts cost to the price of a mid-level automobile (all the labor for design and assembly being volunteer hours).
Some design principles in support of that main goal are:
- use a simple transmission (90 degree twisted chain or toothed belt to an overhead prop shaft)
- have a constant chord wing as much as possible to minimize the number of unique ribs (only the outer wing panels are tapered)
- use lift wires for lighter spar weight, but avoid a preponderance of them
- rudder/elevator only control -- no ailerons
- (though possibly simple 3-position electrically actuated ailerons as an option)
- have a simple pilot fairing -- 2-D symmetrical airfoils and simple geometry
- have basic avionics (altimeter and airspeed), tied to a cell phone for display and GPS recording
As we've worked on this project, we of course realized that nothing is really 'simple' about it, though we are trying to always make our engineering trade-offs in a way that keeps time, cost and expense to a minimum where possible.
Our flight goals are modest -- we want members of the team to be able to fly the plane for short to medium distances, and have a controllable airplane. However, accomplished cyclists with a high power to weight ratio should be able to fly the airplane for many minutes or hours.
We want good performance, so we have eschewed using an aluminum structure (except for the seat) in lieu of a carbon fiber one. This has required extensive CAD (Computer Aided Design) and FEA (Finite Element Analysis) of most of the structural members of the aircraft. And we have several experienced aeronautical engineering advisors who are steering us in the right direction and helping us with aircraft design and propeller design.
 |
| Preliminary 3-View of DaSH v5 airplane |
 |
| DaSH fuselage with fairing outline |
 |
| Wing Planform layout of the v5 and v6 (larger span) versions. |
Some basic Technical Specifications of the current version of the airplane. The airplane comes in four configurations, depending on which wingtips we use to give different wingspans, the base configuration (DaSH v5) is listed first, :
DaSH v5: 33.3 m span version:
Wing Span: 33.3 m (109.25 ft)
Wing Area: 35.97 m^2 (387 ft^2)
Avg. Wing Chord: 1.08 m (3.54 ft)
Root Chord: 1.17 m (3.8 ft) (constant chord middle 3/5 of the wing)
Tip Chord: .735 m (2.4 ft)
Aspect Ratio: 30.83
Empty mass: 44.8 kg (98.76 lbs)
[Target empty mass was: 36.3 kg (80 lbs)]
Flying speed with 72.5 kg (160 lb) pilot: 24.8 kph (15.4 mph)
Power required with 72.5 kg pilot: 275 Watts
Maximum payload (Pilot + consumables): 90 kg (198.5 lbs)
Ultimate load, wing main spar: 2.5 g
Wing tip dihedral at 1 g: 11 degrees
Tail Boom Length (to Vertical Tail 1/4 chord): 6 m (19.7 ft)
Horizontal Tail Span: 4.5 m (14.75 ft)
Horizontal Tail Area: 2.25 m^2 (24.2 ft^2)
Vertical Tail Span: 3 m (9.84 ft)
Vertical Tail Area: 2.55 m^2 (27.4 ft^2)
Propeller Diameter: 3.66 m (12 ft)
DaSH v5-WE 36.3 m span version:
Wing Span: 36.3 m (119 ft)
Wing Area: 38 m^2 (409 sq ft)
Avg. Wing Cord: 1.047 m
Empty mass: 45.7 kg (100.76 lbs)
Flying speed with 72.5 kg (160 lb) pilot: 24.2 kph (15.0 mph)
Power required with 72.5 kg pilot: 258 Watts
DaSH v6 36.98 m span version:
Wing Span: 36.98 m (119 ft)
Wing Area: 38.42 m^2 (414 sq ft)
Avg. Wing Cord: 1.039 m
Empty mass: 45.7 kg (100.76 lbs)
Flying speed with 72.5 kg (160 lb) pilot: 24.07 kph (14.96 mph)
Power required with 72.5 kg pilot: 254 Watts
DaSH v6-WE 39.98 m span version:
Wing Span: 39.98 m (119 ft)
Wing Area: 40.14 m^2 (432 sq ft)
Avg. Wing Cord: 1.004 m
Empty mass: 46.5 kg (102.5 lbs)
Flying speed with 72.5 kg (160 lb) pilot: 23.55 kph (14.63 mph)
Power required with 72.5 kg pilot: 239 Watts
For updates on the project, see our main blog page at: http://dashpa.blogspot.com
If you are interested in joining the project, send e-mail to Alec Proudfoot at alec.proudfoot@gmail.com
<updated 9-Jul-2013 -- by Alec>