|
1)
SIMPLEST
OF ALL AIRCRAFT :
- For the construction of the
fuselage : no millings or specific turnings of parts, neither bendings
of tubes; only straight stainless steel tubes, welded under neutral
gas (T.I.G.).
Time needed for building the fuselage : approximately 100 hours (no
special competence nor special tools needed).
- For the construction of the
wings : no complicated jigs or flat tables. No dihedral or
sweep angles to worry about. No cables or internal rods, no hinges, no
flaps nor ailerons, no upper struts, no sewing of fabrics, no (or just
a few)
handling of dangerous and/or harmful products and materials.
Time needed for building the wings : approximately 100 hours (no
special competence nor special tools needed).
- For the motorization used
: no special adaptation or changes to original stock configuration; no
gearbox or belt reduction, no mixture of fuel with the four-stoke
engine used; very few
vibrations and noise(the exhaust muffler is integrated into the
fuselage base tube); and this industrial engine is very reliable, with
low maintenance needed.
- For piloting ("driving
!)"
: only a throttle and steering wheel. No pedals or
othercontrols and accessories.
2) THE SAFEST OF
ALL AIRCRAFT
:
- Landing, taxiing and ground
handling : with a low and rearward center of gravity, a wide
and long wheel base, and the fuselage
acting as a skid, associated with effective shock absorbers, large
diameter wheels, safe placement of the placement of the pilot's feet, a powerful front
wheel brake, a rigid seat equipped with "4 points"
safety belts, a head-rest, an electric starter, a
propeller well protected from rocks and debris, as well as from
bystanders, an overhead
wing to avoid obstacles, a deformable fuselage in the event of
accident, well triangulated to insure the safety of the pilot.
- In flight
safety : all the exceptional advantages of the "Spratt"
aerodynamical formula used (no stall nor spin, and the aerodynamic
absorption of gust loads), maximum visibility in all directions
due to the high wing
and the pusher engine, good gliding ratio due to a low drag design,
very few vibrations and noise, no icing carburettor in this engine
configuration, great autonomy (6 hours) in spite of the small fuel
quantity (25 liters tank, with directly visible fuel level), small maximum mass and
low landing speed
limiting eventual damage.
3) MOST ECONOMIC OF ALL
AIRCRAFTS:
- Due to its very short construction time and the low cost of the
specific materials used.
Fuselage : uses stainless
steel tubes
of standard size and quality, welded TIG. Other parts, such as the
seat, wheels, fuel tank, baggage container,"Heim" bearing
joints, and other accessories can be found in standard hardware distribution
stores.
The total for fuselage construction parts costs
approximately 500 euros
+ 500 € for the TIG welder.
Wings : wingspars are
made out of square aluminium
tubes of ordinary dimensions and standard quality, extruded
polystyrene (styrofoam) ribs, fiberglass fabric and coating, fixed and simple
rudder.
The total for wing construction parts costing around 500 euros.
Engine : 4 stroke, 25
hp,
of industrial type with electric starter.
Propeller, battery and other
accessories "off the shelves"
items.
The total of motorization parts costing approximately 2 300
to 3 000 euros (depending on where you buy the engine...).
That means a total cost of maximum
4
500 euros, according
to the invoices related to the first prototypes.
- Moreover, this aircraft is conceived to resist bad weather.
Since it can occupy
a space of only 4 m X 1 m X 1,20 meters (folding down in less than 30 minutes),
the "Spratt 103" will have very low expenses to shelter
it.
TECHNICAL
CHARACTERISTICS
The Spratt 103, with its polyvalent concept intended for
general-purpose use (landplane or even amphibious use...) is an ultralight, hybrid aircraft,
mating "trike" pendular stability and "Sprattwing"
concepts togther, with the Spratt free rotating and self-stabilizing
aerofoil, made up of two rigid wings commanded
collectively and differentially by an elegant and simple system.
Single-seater with stainless steel structure welded "TIG" by professional welder (final cost including
this expense). Composite fiberglass/polyester resin wings,
designed specifically for the Spratt 103 by Bernard Geffray, and fully
load tested..
Span: 8 m Length: 4 m
Height: 2 m
Empty weight: 115 kg (including engine 30 kg, and wings 30 kg)
Maximum take off weight : 250 kg
Motorization : industrial 4 stroke engine intially intended for powering
generator units and tractors lawnmowers. This is a robust engine with
very long life, and good reliabilty. (see links)
25 hp @ 3 600 Rpm.
Unleaded gas consumption : averages 4 liters / hour.
Fuel tank : 25 liters
Container acting as baggage space : capacity 25 liters.
Minimum speed : 45 km / H
Maximum cruising : 100 km / H
< < Since July 2001 (date of the first flight)
the flight tests continue... > >
|
