Skycraft Scout

Scout Mk.III

This Australian design was originally built by Ron Wheeler in 1972 as a powered version of his earlier Tweetie hang-glider design. First flown in May 1974, his friends asked him to build them one and by 1976 demand was so high Ron Wheeler set up Skycraft and full-scale production began in November 1976 after the issuing of the ANO 95.10. The stitching of catamaran sails is still evident in the wing of the very early models. The Scout, later dubbed Mk.1, was considerably cheaper than the other types available mainly because it is smaller and doesn’t offer quite the same performance. It is however more economical and resembles in many ways the very first microlight — the Santos Dumont Demoiselle of 1911. The single surface wire braced taildragger has three-axis control via the all flying tail “feathers and wing warping for roll control. Airframe is constructed from high tensile alloy section extruded from the company’s dies. The aircraft sits high on the main wheels, an advantage for its rough strip capabilities. An engine option was available as well as floats and a cockpit pod, and optional Rotax 377 engine. The floats were designed by Wheeler and added to his aircraft in September 1977. The aircraft with floats was first displayed at the Schofield Air Show in 1978.

A historic aircraft in Australia, being the first type to receive certification under to Ultralight classification. The first to do so is in the Powerhouse Museum in Sydney, Australia.

En route, it has gained a modified front axle and seat support (hence the Mk2 title) but otherwise it is little changed. The same 173cc Pixie Major engine is used, driving a tractor propeller, and controls are two axis, operated entirely by the stick and with no separate roll control for the single surface wing. The Scout Mk.2 was a single seat single engined high wing monoplane with two axis control. Wing has unswept leading edge, swept forward trailing edge and tapering chord; conventional tail. Pitch control by fully flying tail; yaw control by fully flying rudder; no separate roll control. Control inputs through stick for pitch/yaw. Wing braced from above by kingpost and cables, from below by cables; single surface wing. Undercarriage has three wheels in tail dragger formation; steel spring suspension on main wheels. Push right go right tailwheel steering connected to yaw control. No brakes. Aluminium tube framework, without pod. Engine mounted at wing height driving tractor propeller. Stainless steel rigging and control cables. Wing material is heavy duty Dacron.

Skycraft Scout 3

The combination of very small fuel tank and low maximum speed means that the Scout is more of a fine weather fun machine than an aircraft for cross country flying. Never the less the Scout has won many friends in its seven years of flying, not least because of its 15 minute rigging time, and has earned its place in the history of the sport.

Skycraft Scout 3

The Scout Mk.3/3/R was a single seat single engined high wing monoplane with conventional three axis control. Wing has unswept leading edge, swept forward trailing edge and tapering chord; conventional tail. Pitch control by fully flying tail; yaw control by fully flying rudder; roll control by wing warping; control inputs through stick for pitch/roll and pedals for yaw. Wing braced from above by kingpost and cables, from below by cables; single surface. Undercarriage has three wheels in tail dragger formation; steel spring suspension on mail wheels. Push right go right tailwheel steering connected to yaw control. No brakes. Aluminium tube framework, without pod. Engine mounted at wing height driving tractor propeller. Stainless steel rigging and control cables. Wing material is heavy duty Dacron. Introduced in 1982 to cater for pilots wanting conventional three axis controls, the Scout Mk3/3/R uses a wing-warping system for roll control. Rudder pedals control yaw and also operate the steerable tailwheel. However, the adoption of three axis control was not the only major change. The Pixie engine was discarded in favour of a 250 Robin, bringing a marked improvement in performance and giving rise to the ‘R’ in the designation title (the second ‘3’ indicates three axis). Typical output for a 250 Robin is 18 hp, but in this application 21 hp is claimed, using an exhaust system engineered specifically for this aircraft. There are also numerous detail engineering changes compared to the Mk2, plus a modified framework which gives better pilot protection.

While the wing warping system has proved effective as a wing levelling device, adverse yaw can be experienced under some circumstances and further modifications to eliminate this have been designed by one of Britain’s Scout dealers as the Flylite (East Anglia) Super Scout.

Scout Twin Mk.4 courtesy Steven Walker

The Scout Twin Mk.4 was powered by a Rotax 377 engine and featured a fibreglass fuel tank, moulded to the fuselage and over the C of G, and a moulded fibreglass cockpit. The Mk.IV can also be fitted with floats. About 50 of these were built.

Scout Twin Mk.4 fuel tank courtesy Steven Walker

Components such as the moulded cockpit will fit the Mk.III as will the dual wire drag system. The aerolastic structure has been truck tested to air loads above 80 mph.

A further enclosed version was built.

courtesy Steven Walker

And another version place the pilot position above the fuselage.

courtesy Steven Walker
courtesy Steven Walker
courtesy Steven Walker

Variation: Mahe Pfadfinder

Gallery

Scout Mk.I
Engine: Pixie Major, 14hp at 6500rpm
Propeller diameter 48 inch, 1.23 m
V belt reduction, ratio 3.0/1
Max static thrust 79 lb, 36 kg
Power per unit area 0.13 hp/sq.ft, 1.4hp/sq.m
Fuel capacity 0.6 US gal, 0.5 Imp gal, 2.5 litre
Length overall 17.1 ft, 5.20 m
Height overall 6.2ft, 1.90m
Wing span 28.8ft, 8.77 m
Chord at root 6.5ft, 1.98 m
Chord at tip 1.3ft, 0.40m
Sweepback 0 deg
Tailplane span 10.5ft, 3.2m
Rudder height 4.8 ft, 1.47 m
Total wing area 109 sq.ft, 10.1 sq.m
Total elevator area 12.5 sq.ft, 1.16 sq.m
Wing aspect ratio 17/1
Wheel track 4.5ft, 1.37m
Wheelbase 12.5ft, 3.80m
Tailwheel diameter overall 4 inch, 10cm
Main wheels diameter overall 12 inch, 31 cm
Empty weight 122 lb, 55.5 kg
Max take off weight 297 lb, 135 kg
Payload 175 lb, 79.5 kg
Max wing loading 2.72 lb/sq.ft, 13.4 kg/sq.m
Max power loading 21.21b/hp, 9.65kg/hp
Load factors; >+3.0, > 3.0 ultimate
Max level speed 47 mph, 75 kph
Never exceed speed 75 mph, 120 kph
Max cruising speed 40 mph, 65 kph
Economic cruising speed 40 mph, 65 kph
Stalling speed 20 mph, 32 kph
Max climb rate at sea level 200ft/min, 1.0m/s
Min sink rate 510 ft/min at 40 mph, 2.6 m/s at 65 kph
Best glide ratio with power off 7/1 at 40 mph 65 kph
Take off distance 230 ft, 70 m
Land¬ing distance 100ft, 30m
Service ceiling 9900ft, 3000m
Range at average cruising speed 28 mile, 45 km

Mk.III
Engine: Robin 244cc 2 stroke
Wing Span: 28 ft 6 in (8.8 m)
Wing Area: 149 sq. ft
Cruise speed: 46 mph (75 kmh)
Stall speed: 19 mph (32 kmh)
Max speed: 105 kph
Max. rate of climb: 550 fpm
Empty weight: 130 lb (58.03 kg)
Max. pilot weight: 205 lb (91 kg)
Engine: 244 cc/19 hp Fuji Robin 1-cylinder Two-stroke
Fuel capacity: 19 ltr
Prop: 122cm
Range: 55 miles

3/3/R
Engine: Robin EC25PS, 21 hp at 6500 rpm
Propeller diameter: 48 inch, 1.23 m
V belt reduction, ratio 2.2/1
Max static thrust 130 lb, 59 kg
Power per unit area 0.19 hp/sq.ft, 2.1 hp/sq.m
Fuel capacity 1.6 US gal, 1.3 Imp gal, 6.0 litre
Empty weight 130lb, 59kg
Max take off weight 310 lb, 141 kg
Payload 1180 lb, 82 kg
Max wing loading 2.84 lb/sq.ft, 14.0 kg/sq.m
Max power loading 14.8 lb/hp, 6.7 kg/hp
Load factors design; >+3.0, > 3.0 ultimate
Max level speed 53 mph, 85 kph
Never exceed speed 75 mph, 120 kph
Max cruising speed 47 mph, 75 kph
Economic cruising speed 47 mph, 75 kph
Stalling speed 20 mph, 32 kph
Max climb rate at sea level 550 ft/min, 2.8 m/s
Min sink rate 470 ft/min at 40 mph, 2.4 m/s at 65 kph
Best glide ratio with power off: 7/1 at 40 mph, 65 kph
Take off distance 130 ft, 40 m
Land¬ing distance 100ft, 30m
Service ceiling 9900ft, 3000m
Range at average cruising speed 56 mile, 90 km

Scout Twin Mk.4
Engine: Rotax 377
Empty weight: 82 kg
AUW: 180 kg
Wingspan:8.7 m
Wing loading: 7 kg/sq.m
Takeoff distance: 25-40 m
Landing roll: 24-30 m
Stall: 32 kph
ROC: 600 fpm
Max speed: 100 kph
Cruise: 75 kph
Glide ratio: 7-1
Fuel capacity: 15 lt
Fuel burn: 8 lt/hr

Mk.4 Twin courtesy Steven Walker

Skyacht Aircraft Alberto

Since 2002 Skyacht Aircraft, Inc. has been developing Personal Blimp. The Personal Blimp uses hot air for lift and silent electric motors for propulsion. Initial flight tests are using a conventional gas-powered motor. Electric motors will be added once these initial tests are complete. Similarly, the initial flight tests are being made with conventional hot air balloon burners. Quiet burners were to be added later. The Personal Blimp flies “low, slow, and smooth.”

The Personal Blimp hull structure has three main components: 1) the fabric envelope, 2) a set of flexible ribs embedded within the fabric, and 3) a tensioning line that runs along the central axis of the hull.

The hull is a “tension structure” wherein the ribs are under compression and the fabric and tensioning line are under opposing tension.

What is new and different about the Personal Blimp hull design is the ease with which one can create a lightweight, sturdy, self-supporting (no fans required) airship envelope.

The fabric of the envelope has several continuous, tubular sleeves sewn into it running from nose to tail. The ribs are inserted into the sleeves. The ends of the ribs are held together at each end. The tensioning line is then connected between the two ends and the whole contraption is inflated by pulling on the tensioning line. As the tensioning line is made shorter the ribs are forced to bend or “bow” outward. The envelope continues to expand until eventually the fabric is pulled taut.

Different shapes can be designed by varying the composition and/or cross section of ribs along their length. For instance, making the ribs more flexible towards the nose gives a blunter shape to the front of the ship. Relatively stiffer ribs can also be used to get a longer, skinnier shape.

When not in use, the Personal Blimp can be deflated and folded for storage. The combination of ready buoyancy control and rapid deflation eliminates not only hangars but also the large ground crews.

The Personal Blimp has a rigid, but folding, skeleton to allow the envelope to retain its shape without requiring internal air pressurization. Patent (USPTO #6,793,180) for this unique structural design in September of 2004. The Personal Blimp’s rigid but foldable structure provides hardpoints at strategic locations (e.g. on the tail) for mounting systems such as the engine and propeller. With the engine/propeller mounted on the tail, the Personal Blimp can use vectored thrust for steering. This provides far greater maneuverability.

Since its first flight on October 27, 2006, the Alberto has completed more than 50 hours of flight testing. Work focuses on both refining its systems and further expanding its capabilities.

Gallery

Engine: 20 hp
Length: 102 Feet
Diameter: 70 Feet
Maximum Weight: 4,100 pounds
Size in Flight: 205,000 cubic feet
Size When Deflated/Folded: 1,500 cubic feet
Envelope – Nylon Fabric over Aluminium Ribs
Car, Nose and Tail Cones – Welded Steel Framework
Lifting Gas: Hot Air
Cruise Speed: 10 mph
Seats: 2

Skonkworks 24bis

AirVenture Oshkosh 2017

The 24 Bis (that’s what they call the example you see in the images) is a tribute to Alberto Santos Dumont.

The Winchester Skonkwerks Ultralight Research and Development Facility —shortened to Skonkwerks — represents a team from Larsen, Wisconsin. Skonkwerks honored Alberto by first building a 23 Bis and later the 24 Bis. The group describes itself as a “loosely knit organization of friends, flyers, and fanatics… tinkerers, builders, and bullsh###rs. We are engineers, designers, and dreamers hanging out in a little hangar screwing stuff together and making it fly.”

AirVenture Oshkosh 2017

Lee Fischer was the founder of this group of tinkerers that formed after he first showed a highly modified Robertson B1-RD. So much interest was shown in the Demoiselle style of aircraft that he decided to build a 23 Bis. At AirVenture 2015, his friend Mark Solper hinted that it would be “great project to build a pair of ‘evolved’ Demoiselles for a subsequent AirVenture.” This suggestion led to the 24 Bis.

Mark, Lee, and the whole merry band machined and welded the airframe and sewed Dacron wings, all the while learning both new skills and an appreciation for what Santos Dumont and his associates had done more than a hundred years earlier.

The aircraft was flown into Oshkosh.

AirVenture Oshkosh 2017

Weight — 240 pounds
Wing Span — 32 feet
Wing Area — 192 square feet
Never Exceed Speed — 45-50 mph
Stall Speed — 14-16
Engine — Rotax 447
Build Time — December 21, 2014 through June 21, 2015

Skonkworks 23bis

The Winchester Skonkwerks Ultralight Research and Development Facility — let’s shorten that to Skonkwerks — represents a team from Larsen, Wisconsin. Skonkwerks honored Alberto Santos Dumont by first building a 23 Bis and later the 24 Bis. The group describes itself as a “loosely knit organization of friends, flyers, and fanatics… tinkerers, builders, and bullsh###rs. We are engineers, designers, and dreamers hanging out in a little hangar screwing stuff together and making it fly.”

Lee Fischer was the founder of this group of tinkerers that formed after he first showed a highly modified Robertson B1-RD. So much interest was shown in the Demoiselle style of aircraft that he decided to build a 23 Bis. At AirVenture 2015, his friend Mark Solper hinted that it would be “great project to build a pair of ‘evolved’ Demoiselles for a subsequent AirVenture.” This suggestion led to the 24 Bis

Weight: 240#
Wing Span: 32′
Length: 19′
Wing Area @ Chord: 176 sq. ft.
Wing Area @ Camber: 192 sq. ft.
Wing Construction: Tube and Sewn Dacron

Skoda-Kauba SK V4 / SK 257

SK V4

The Škoda-Kauba Flugzeugbau produced the Škoda-Kauba V4 as a single-seat low-wing cantilever monoplane powered by a 240 hp (179 kW) Argus As 10C-3 engine with a retractable tailwheel landing gear. First flying in 1943, the first prototype proved very fast for its low power. The second included a number of changes and, despite increased power, was not as fast. A third was also completed.

The SK V4 fighter trainer was the only Otto Kauba design put in to production as the SK 227. The production was somewhat limited though.

The potential for development was recognized and the German Reichsluftfahrtministerium ordered four prototypes of an enlarged aircraft with a more powerful 485 hp Argus As 410 engine and allocated the designation Sk 257. The four prototypes performed well and the type was ordered into production but the build quality of the prototypes did not pass the Luftwaffe quality control inspections and after only five production aircraft had been built the order was cancelled.

The SK257 development received a German production order and five were completed before the Russians captured the factory.

SK V4
Engine: 1 x 240hp Argus As 10C-3
Max take-off weight: 1250 kg / 2756 lb
Wingspan: 7.60 m / 24 ft 11 in
Length: 5.60 m / 18 ft 4 in
Height: 2.90 m / 9 ft 6 in
Max. speed: 420 km/h / 261 mph
Ceiling: 7500 m / 24600 ft
Range: 900 km / 559 miles
Crew: 1

SK 257
Engine: 1 × Argus As 410 362 kW (485 hp)
Wingspan: 7.6 m (24 ft 11 in)
Wing area: 8.4 m2 (90 sq ft)
Length: 7.1 m (23 ft 4 in)
Maximum speed: 350 km/h (217 mph, 189 kn)
Crew: 1

Sklenar Tatra T-101.2

Over a 10 year period Jiri and Ivo Sklenar created a replica Tatra T-101 (designated T.101.2). An original 1938 Tarta T-100 engine was overhauled by the original Tatra Company, and apart from some safety and cost effective material compromises, the replica deviates little from the sole produced original aircraft.

The aircraft features a 13 metre span, one piece wooden wing with 11 fuel tanks. This allows for approximately 30 hours flying time.

The replica was first flown from Kunovice airport, Czechoslovakia, by Stanislav Sklenar on 29 September 2007.