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Solar Wings Scandal Gallery
Author: Terry
Solar Wings Scandal
Under power the large & small Scandal (kingposted) goes exceptionally well. The spiral stability is good and handling firm, but not stiff.
The Solar range of gliders were unique in that they had 100% double surface at the tips. The key to this was a “rubber membrain” which allowed the upper and lower surface to move relative to each other. This was dropped on the Scandal range of gliders, when Solar introduced a presurised leading edge. This prevents the leading edge from colapsing when flying at high speed. It has a clever active pressure system – At low speed the holes in the leading edge are in the low pressure air, so it sucks air out of the double surface, giving concave lower surface at the wing tips, effectively adding camber to the wing. The Solar Gliders had a reputation for being more stable and less “twitchy” or sensitive. It was claimed that it gave a 13 % improvement in top speed and an 11 % reduction in stall speed to the 1995 Scandal.
The 1995 Scandal wing is ‘uniform’, easy to fly, to take-off, to land, and it accepts slow flight. Slow landings even with AUW over 100kg and sink rate with engine off 220 fpm. Neutral ground handling, not tail heavy. A much nicer glider than the Rumour. Handling better and more docile in pitch while thermaling. Lighter, stiffer leading edges & X tubes made big difference to the weight.
The Scandal 13.6 has a very nice glide, good penetration into wind and is a real confidence builder when you come to landing.
This is a very nice glider for a small light pilot. The glider is quite light. The A frame is small and “fits my shoulders”. Landing – no vices good large flare window. This glider has vents in the leading edge which stop it from collapsing at high speed. They seem to work, in that at high speed the Glide Angle does not deteriate as fast as other gliders.
Stright line at speed it is stable. Thermaling and scratching the ridge the glider is nice and responsive, and not too sensitive to turbulance. A very nice glider with great glide ratio but rather slow to initiate a turn. The wing has a tendency to drop the nose when held against the wind on take off. But as soon as you start running the wing behaves normal and the take off is just as easy as with any modern glider. Easy to land as well, light in construction and easy to set up.
The 1997 Scandal XK was Solarwing’s first kingpostless glider. The Scandal XK was claimed to be only 1.5 kgs heavier than the standard kingposted Scandal.
The Scandal XK cross boom is of composite construction and was designed by Dr Bill Brooks. There are 23 battens (including 4 lower), the airframe material is 7075-T6 and HT30-TF, and it was priced at £3795.00.
After the kingposted Scandal came the topless XK then the 2000 XK-R which had a roll-assist hang point arrangement. Said to be out-performed on glide by contemporary gliders such as the Laminar and rather variable in handling between different examples.
Scandal 12.4
Wing area: 12.4 sq.m
Certification: BHPA
Pilot weight: 48-68 kg
Wing span: 9.4 m
Nose Angle: 131 degs
Aspect ratio: 7.1
Price (1998) £ 3350
Scandal 13.6
Wing area: 13.6 sq.m
Certification: BHPA
Pilot weight: 58-78 kg
Wing span: 9.9 m
Nose Angle: 131 degs
Aspect ratio: 7.3
Price (1998) £ 3350
Scandal 14.4
Wing area: 14.4 sq.m
Certification: BHPA
Pilot weight: 72-92 kg
Wing span: 10.35 m
Nose Angle: 131 degs
Aspect ratio: 7.44
Price (1998) £ 3350
Scandal XK
1997
Wing area: 13.2 m²
Minimum pilot weight: 75 kg
Maximum pilot weight: 95 kg
Minimum speed: 28 km/h
Maximum speed: 90 km/h
Number of battens: 23
Scandal XK 13.6
Wing area: 13.6 sq.m
Certification: BHPA
Pilot weight: 58-78 kg
Wing span: 9.9 m
Nose Angle: 131 degs
Aspect ratio: 7.3
Price (1998) £ 3795
Scandal XK 14.4
Wing area: 14.4 sq.m
Certification: BHPA
Pilot weight: 72-92 kg
Wing span: 10.35 m
Nose Angle: 131 degs
Aspect ratio: 7.44
Flying weight: 32.5 kg
Packed length: 5.8 m
Double surface: 85%
Price (1998) £ 3795
Scandal XK-R 13.6
Wing area: 13.6 m²
Wing span: 9.9 m
Aspect ratio: 7.3
Minimum pilot weight: 58 kg
Maximum pilot weight: 78 kg
Nose angle: 127°
Scandal XK-R 14.4
Wing area: 14.4 m²
Wing span: 10.35 m
Aspect ratio: 7.44
Minimum pilot weight: 72 kg
Maximum pilot weight: 92 kg
Nose angle: 127°
Solar Wings Rumour / Fever
The 1989 Rumour was a fast, small, light, efficient and very clean glider which featured a new lightweight airframe, enclosed tip rods, enclosed keel, sealed kingpost hole and it was without a keel pocket.
Other features were 100 % double surface tips, VB, and rubber backed airfoil uprights.
The Rumor allowed Solar Wings to keep up with its UK competitor (i.e. Airwave) by winning the French and Italian championships in 89 and the UK ones in 89 and 90.
Very stable glider good in a straight line, but can be a little stiff in roll. Easy landings and rock solid in turbulance.
Plenty of examples around so not too expensive-good intermediate glider with reasonable performance, for 35hrs + pilot wanting to upgrade on a budget in May 2007 for £200.
The 1991 Rumour 2 had a new high-aspect ratio sail, a kingpost hang point, luff-line compensator and slightly reduced wing area in pursuit of improved handling and better glide at speed. The battens were of 7075.
The Rumour 2 has very good min sink despite being near the top of its weight range. Compared to the Rumour 3, it is not so sensitive in roll but the K/P hang point makes it not too bad. Pitch sensitivity is high, but not unpleasantly so. Glide-on in ground effect is long, but landing without a drag chute is easily achievable.
There are 14 top battens (15 including static one), 2 tip battens and 6 undersurface battens – 23 in total.
From 40 kph the sink rate of the Rumour 2 14 increases considerably. It is a “hard” wing that it costs to leave its inertia, therefore stable. Especially at low speeds (where it has its best performance) requires a very physical piloting and the knowledge of some tricks like the “penduleo” to start the turns. Although it lands well in the final braking, this awkwardness and slowness of reaction is also a problem for approach, which requires some anticipation.
The 1992 Fever is a new light weight glider for the smaller pilot, priced at £2850.00 inc VAT. Later models were designated Rumour Fever MK2. They were later updated with mods to the sail and airframe with reduced anhedral to improve roll response. It was claimed to have better roll control, yaw stability and glide performance at speed.
The 1993 Rumour 3 is one of the last Kingpost designs and has very high performance and light handling characteristics. It has excellent performance at low and high speed. Landing characteristics are docile, but float in ground effect if coming in fast is very long. Roll control is lighter than the 2. Oddly, it has no wingtip washout struts.
The 1992 Fever 2 roll was much faster and easier pitch than the Rumour 1 (13m).
The 1992 Rumour 3 looks similar to its predecessor but the handling was been improved giving much lighter roll. The bar position was changed from the Rumour 2 so that it is 4 cm further forward. The advantages of this are that when flying in ‘budgie’ position more speed can be pulled on before the bottom bar reaches the pilot’s body, enabling pilots to take off and approach to land at higher speeds. Also a higher top speed can be flown. The Rumour 3 was produced in two sizes; 13 sq m and 14 sq m. The certification was BHPA C of A (No.9306090). The airframe material was 6082 TF T6 and battens 7075.
The Rumour 3 Special Edition was only available between November 1 1993 and end of February 1994.Cost £3000.00. The glider featured blue leading edges, light grey top surface and Solar logo.
Rumour 13
1989
Wing area: 13 m²
Wing span: 9.44 m
Aspect ratio: 6.6
Hang glider weight: 34 kg
Number of battens: 12
Nose angle: 128°
Rumour 14
1989
Wing area: 14.5 m²
Wing span: 10.5 m
Aspect ratio: 6.96
Hang glider weight: 34 kg
Number of battens: 12
Nose angle: 128°
Rumour 2 13
1991
Wing area: 13 m²
Wing span: 9.6 m
Aspect ratio: 5.6
Minimum pilot weight: 58 kg
Maximum pilot weight: 80 kg
Nose angle: 127°
Stall speed: 31 kph
Maximum speed: 95 kph
Glide ratio: 11
Rumour 2 14
1991
Wing area: 14 m²
Wing span: 10.1 m
Aspect ratio: 5.1
Minimum pilot weight: 65 kg
Maximum pilot weight: 90 kg
Nose angle: 127°
Stall speed: 31 kph
Maximum speed: 95 kph
Glide ratio: 11 at 37 kph
Min sink rate: 0.95 m/s
Rumour 3 13
Wing area: 13 sq.m
Certification: DHV 3/BHPA
Pilot weight: 60-75 kg
Wing span: 9.6 m
Nose Angle: 127 degs
Aspect ratio: 7.1
Price (1998) £ 2850
Rumour 3 14
Wing area: 14 m² / 151 sq ft
Wing span: 10.1 m / 33 ft 2 in
Aspect ratio: 7.3
Weight: 31.7kg / 70 lbs
Minimum pilot weight: 70 kg / 154 lb
Maximum pilot weight: 85 kg / 187 lb
Nose angle: 127°
Packed length: 5.8 m / 19 ft
Double surface: 85 %
Battens: 25 (6 undersurface)
Rumour 3 15
Wing area: 14.8 m²
Wing span: 10.4 m
Aspect ratio: 7.4
Minimum pilot weight: 80 kg
Maximum pilot weight: 95 kg
Nose angle: 127°
Rumour Fever 12
1992
Wing area: 12.1 m²
Wing span: 9.2 m
Aspect ratio: 7
Minimum pilot weight: 45 kg
Maximum pilot weight: 65 kg
Nose angle: 127°
Fever
Sail area: 12 sq m
Weight: 27kg / 60lb
Fever Compet
1992
Wing area: 12.1 m²
Wing span: 9.2 m
Aspect ratio: 7
Minimum pilot weight: 45 kg
Maximum pilot weight: 65 kg
Nose angle: 127°
Solar Wings Breeze
Made during 1996-8, the Breeze fits into the category of a sports glider as its performance is above that of a floater and exhibits some of the attributes of the higher performing hang gliders.hang glider. Price (1998) £ 1997.
The Breeze features 15 battens, round uprights, and speed bar.
Breeze
Sail area: 15 sq m
Span 9.4 m
Nose angle: 125 degs
Aspect ratio: 5.6:1
Weight: 28 kg
Pilot weight: 60-80 kg
Top speed: 50 mph
Packed length: 5.5m
Double surface: 61%
Breeze
Wing area: 15 m²
Wing span: 9.4 m
Aspect ratio: 5.6
Hang glider weight: 27 kg
Minimum pilot weight: 65 kg
Maximum pilot weight: 80 kg
Minimum speed: 25 km/h
Maximum speed: 80 km/h
Max glide ratio (L/H): 10
Max glide ratio speed: 50 km/h
Minimum sink rate: 1 m/s
Nose angle: 125°
Certification: BHPA
Solar Wings Pegasus
A two seat trike developed from the Rogallo sailwing.
Quantum 15
XL-R
Flash II
Photon
Solar Wings Typhoon
The 1980 Typhoon was the first double surface Comet clone produced by Solar Wings, in two sizes. The Typhoon followed the formula fairly closely with preformed battens and four undersuface battens. Reflex being retained by a harness of lines attached to the trailing edge from the kingpost.
Although the glider handled nicely it is rather heavy. Three hundred and thirty-four sold.
The 1982 Typhoon S was brought out by Solar Wings to counter improvements made to the Airwave Magic. In line with the policies of these two dominant companies no specification or details of changes made were publicised (184 sold). Priced from £943.00 plus VAT.
The Typhoon SS has been introduced to give another increase in handling and performance, attributed in part to the lay of the cloth being bias-corrected to the trailing edge and in part to further modification of the tips. The trailing edge, previously taped, was folded over. (226 sold).
The Typhoon range resulted in the 1983 Typhoon S4 which is intended to be Solar’s answer to the successful Magic 3. The 1983 Typhoon S4 was priced from £865.00 plus VAT.
The 1984 S4 Racer was originally based on a standard S4 with a package of options added, these including the mylar leading edge, airfoil kingpost and control-frame sides and 8 undersurface battens. However a variable billow system has put the machine into a class of its own. Decreasing the nose angle increases the billow, improving the handling at the expense of speed, thus the low setting is selected for thermalling.
When leaving the thermal the pilot can select the maximum nose angle and by tightening the sailcloth decrease the drag coefficient substantially, making the S4 Racer one of the fastest hang gliders in the world, despite it’s friendly handling characteristics. The S4 Racer was priced at £1115.00 inc VAT.
The 1985 S4 Racer GP was developed specifically for professional competition pilots, it’s tough mylar sandwich sail ensuring that it remained accurately tuned during the punishment of top competition.
The S4 Racer GP has mylar sandwich sail, mylar leading edge, nose cone, keel and tip fairings, airfoil control frame sides, speed bar, 8 undersuface battens and Variable Billow.
Although the S4 performs well in international and national competitions it was just as suitable for the intermediate pilot. Decent take-off and landing speeds with smooth positive response make it a safe, enjoyable experience every time you take it into the air.
The 1985 S4 was very good in rough conditions, with great roll response without winding into turns too quickly. It was available in two sizes: 166 and 180.
The Typhoon 85 Racer appeared in 1986.
Typhoon medium
Weight: 73 lb
L/D: 11:1 claimed
Approx 55% double surface
Typhoon S medium
Sail area: 166 sq ft
Span: 32 ft 6 in
Nose angle: 122 deg
Aspect ratio: 6.4
Glider weight: 72 lb
Min-sink: 180 ft min
Double surface: 55 %
Typhoon S4 medium
Sail area: 166 sq ft
Span: 32 ft 6 in
Nose angle: 122 deg
Aspect ratio: 6.4
Glider weight: 72 lb
Min-sink: 180 ft min
Double surface: 55 %
Solar Wings
The 1980 Storm was the first offering of Solar Wings, the new company, based at Marlborough, Wilts. The directors of the company are Mark Southall, Dave Raymond, Cliff Ingram, Roland Lewis-Evans.
1998: Elm Tree Park Manton, Marlbrough, SN8 1PS Wilts, United Kingdom
Since ceasing production of the Scandal (King post and XK) gliders, Solar has concentrated on manufacturing micro-lights.
Solar-Powered Aircraft Developments Solar One
The Solar One, made its public debut June 1979. 750 solar cells charge 24 accumulator cells to drive four electric motors linked together for a combined 4 hp. The aircraft, which looks like a conventional glider but with a pylon mounted power unit located on the nose immediately forward of the pilot, takes off at 20kts and has reached a maximum of 42kts.
Solar-Powered Aircraft Developments
1980: 5A Lyndhurst Gardens, London NW3, UK.
Built the Solar One electric powered airraft
Solar Impulse S-10
Solar Impulse is a Swiss long-range solar powered aircraft project developed at the École Polytechnique Fédérale de Lausanne. The project eventually hopes to achieve the first circumnavigation of the Earth by a piloted fixed-wing aircraft using only solar power. The project is led by Swiss psychiatrist and aeronaut Bertrand Piccard, who co-piloted the first balloon to circle the world non-stop, and Swiss businessman André Borschberg.
Piccard initiated the Solar Impulse project in 2003. By 2009, he had assembled a multi-disciplinary team of 50 specialists from six countries, assisted by about 100 outside advisers. The project is financed by a number of private companies. The four main partners are Deutsche Bank, Omega SA, Solvay, and Schindler. Other partners include Bayer MaterialScience, Altran, Swisscom and Swiss Re (Corporate Solutions). Other supporters include Clarins, Semper, Toyota, BKW and STG. The EPFL, the European Space Agency (ESA) and Dassault have provided additional technical expertise, while SunPower provided the aircraft’s photovoltaic cells.
The first aircraft, bearing the Swiss aircraft registration code of HB-SIA, is a single-seater monoplane, capable of taking off under its own power, and intended to remain airborne up to 36 hours. This aircraft conducted its first test flight in December 2009, and first flew an entire diurnal solar cycle, including nearly nine hours of night flying, in a 26-hour flight on 7–8 July 2010. Piccard and Borschberg completed successful solar-powered flights from Switzerland to Spain and Morocco in 2012, and conducted a multi-stage flight across the USA in 2013.
With a non-pressurized cockpit and a limited flight ceiling, the HB-SIA is primarily a demonstrator design. The plane has a similar wingspan to the Airbus A340 airliner. Under the wing are four nacelles, each with a set of lithium polymer batteries, a 10 hp (7.5 kW) motor and a twin-bladed propeller. To keep the wing as light as possible, a customised carbon fibre honeycomb sandwich structure is used.
Under the wing, 4 nacelles are fixed, each containing a 10-HP motor, a set of lithium polymer batteries and a management system that controls the maximum load and temperature limit. Thermal insulation is conceived to conserve the heat released by the batteries and thus allows them to function despite the -40 ° C encountered at 8500 meters. Each motor is provided with a reducer that limits the rotation of a propeller with two blades of 3.5 meters in diameter to 200-400 revolutions / minute.
11,628 photovoltaic cells on the upper wing surface and the horizontal stabilizer generate electricity during the day. 10,768 solar cells on the wing and 880 on the horizontal stabilizer. 200 cubic meters of photovoltaic cells and 12% of the total efficiency of the propulsion chain, the average power generated by the 4 engines of the plane, does not exceed 8 CV or 6 KW. These both propel the plane and charge its batteries to allow flight at night, theoretically enabling the single-seat plane to stay in the air indefinitely. The 11628 150 micron thick monocrystalline silicon cells have been selected for their quality of lightness, flexibility and efficiency. At 22%, its performance could have been even better, but its weight would then have been excessive, penalizing the aircraft during night flight. As this phase is the most critical, the main difficulty of the project is at the level of energy storage in polymer lithium batteries.
Reaching a 63.40 m wingspan for a fully equipped 1600 kg is a challenge never before experienced in aeronautics in terms of rigidity, lightness and flight control. Solar Impulse is built around a structure in composite materials made up of carbon fiber and honeycomb assembled in a sandwich. The upper surface of the wing is covered with a skin composed of encapsulated solar cells, and the underside of a high resistance flexible film. 120 carbon fiber ribs distributed all 50cm outline these two layers to give them their aerodynamic shape.
The aircraft’s major design constraint is the capacity of the lithium polymer batteries. Over an ideal 24-hour cycle, the motors will deliver a combined average of about 8 hp (6 kW), roughly the power used by the Wright brothers’ pioneering Flyer in 1903. As well as the charge stored in its batteries, the aircraft uses the potential energy of height gained during the day to power its night flights.
On 26 June 2009, the Solar Impulse was first presented to the public in Dübendorf, Switzerland. Following taxi testing, a short-hop test flight was made on 3 December 2009, piloted by Markus Scherdel. André Borschberg, co-leader of the project team, said of the flight:
"It was an unbelievable day. The airplane flew for about 350 metres (1,150 ft) and about 1 metre (3 ft 3 in) above the ground ... The aim was not to get high but to land on the same runway at a speed to test its controllability and get a first feeling of its flying characteristics ... the craft behaved just as the engineers had hoped. It is the end of the engineering phase and the start of the flight testing phase."
On 7 April 2010, the HB-SIA conducted an extended 87-minute test flight, piloted by Markus Scherdel. This flight reached an altitude of 1,200 m (3,937 ft). On 28 May 2010, the aircraft made its first flight powered entirely by solar energy, charging its batteries in flight.
On 8 July 2010, the HB-SIA achieved the world’s first manned 26-hour solar-powered flight. The airplane was flown by André Borschberg, and took off at 6:51 a.m. Central European Summer Time (UTC+2) on 7 July from an airfield in Payerne, Switzerland. It returned for a landing the following morning at 9:00 a.m. local time. During the flight, the plane reached a maximum altitude of 8,700 m (28,500 ft). At the time, the flight was the longest and highest ever flown by a manned solar-powered aircraft; these records were officially recognized by the Fédération Aéronautique Internationale (FAI) in October 2010.
On 13 May 2011, at approximately 21:30 local time, HB-SIA landed at Brussels Airport, after completing a 13-hour flight from its home base in Switzerland. It was the first international flight by the Solar Impulse, which flew at an average altitude of 6,000 ft (1,829 m) for a distance of 630 km (391 mi), with an average speed of 50 km/h (31 mph). The aircraft’s slow cruising speed required operating at a mid-altitude, allowing much faster air traffic to be routed around it. The aircraft was piloted by Andre Borschberg. The project’s other co-founder, Bertrand Piccard, said in an interview after the landing: “Our goal is to create a revolution in the minds of people…to promote solar energies – not necessarily a revolution in aviation.”
A second international flight to the Paris Air Show was attempted on 12 June 2011, but the plane turned back half-way and landed back in Brussels, where it had taken off, due to adverse weather conditions. In a second attempt on 14 June, André Borschberg successfully landed the aircraft at Paris’ Le Bourget Airport at 9:15 pm after a 16-hour flight.
On 5 June 2012, the Solar Impulse successfully completed its first intercontinental flight, flying a 19-hour trip from Madrid, Spain, to Rabat, Morocco. During the first leg of the flight from Payerne, Switzerland, to Madrid, the aircraft broke several further records for solar flight, including the longest solar-powered flight between pre-declared waypoints (1,099.3 km (683 mi)) and along a course (1,116 km (693 mi)).
On 3 May 2013, the plane began its first cross-US flight with a journey from Moffett Field in Mountain View, California, to Phoenix Sky Harbor International Airport in Arizona. Successive legs of the flight took the Solar Impulse to Dallas-Fort Worth airport, Lambert–St. Louis International Airport and Washington Dulles International Airport; it finally concluded at New York’s John F. Kennedy International Airport on 6 July. Each flight leg took between 19 and 25 hours, with multi-day stops in each city between flights.
After the first leg to Phoenix, the aircraft completed the second leg of its trip on 23 May, landing at Dallas-Fort Worth International Airport. This flight, which covered 1,541 kilometres (958 mi), set several new world distance records in solar aviation. On 4 June, the plane landed in St. Louis, Missouri. It departed for Washington DC on 14 June, briefly stopping in Cincinnati, Ohio, to change pilots and avoid strong winds. On 16 June, the plane landed at Washington Dulles International Airport in Virginia. On 6 July 2013, following a lengthy layover in Washington, Solar Impulse completed its cross-country journey, landing successfully at New York City’s JFK International Airport at 11:09 p.m. EDT. The landing occurred three hours earlier than originally intended, because a planned flyby of the Statue of Liberty was cancelled due to severe damage to the aircraft’s left wing. The Solar Impulse was placed on public display at JFK after its landing.
Solar Impulse pilot André Borschberg completed the record-setting flight after flying more than 950 miles on solar power alone. Borschberg landed in Dallas with his batteries at about 60 percent, and used that juice to begin the third leg of his journey. As the headwind exceeded the speed of the airplane at times, Borschberg traveled backward relative to the ground. At one point, a little less than three hours before he actually landed, he was only 20 miles or so from Dallas/Fort Worth International Airport and found himself lined up with runway 13L, where he planned to touchdown. Landing on 13L required closing the runway, and there was simply too much commercial traffic. It was after midnight before air traffic control allowed him to land, so he spent the intervening hours in a holding pattern above the runway. As he descended, the windspeed increased and he encountered a 25- to 30-knot wind at 2,000 to 3,000 feet. This meant Borschberg had to be careful not to turn downwind, because he would be blown too far north and would have to make another approach to land, covering the ground at less than five miles per hour with the headwind. The sideways translation eventually brought him over the top of runway 13L, where he touched down 23 May 2013, at 1:08 a.m. local time, 18 hours and 21 minutes after departing Phoenix.
The flight to Dallas was fairly smooth, with just a few sections of turbulence. Flying 832 nautical miles (957 miles) broke the team’s own distance record for a solar powered airplane (and for any electric airplane). It also provided valuable experience and expand the Solar Impulse team’s flight techniques for future flights — including their planned circumnavigation of the world in a larger aircraft in 2015.
Construction of the second Solar Impulse aircraft, carrying the Swiss registration HB-SIB, started in 2011. The wingspan of HB-SIB will be 80.0 m (262.5 ft), slightly wider than an Airbus A380, the world’s largest passenger airliner, but unlike the 500-ton A380, the carbon-fibre Solar Impulse will weigh little more than an average automobile. It will feature a larger, pressurized cockpit and advanced avionics to allow for transcontinental and trans-oceanic flights. Supplemental oxygen and various other environmental support systems will allow the pilot to cruise at an altitude of 12,000 metres (39,000 ft).
Completion was initially planned for 2013, with a circumnavigation of the globe in 20–25 days in 2014. However, following a structural failure of the main spar during static tests in July 2012, a more likely date for the circumnavigation is 2015. The flight would circle the world in the northern hemisphere, near the equator. Five stops are planned to allow changes of pilots. Each leg of the flight will last three to four days, limited by the physiology of each pilot. Once improved battery efficiency makes it possible to reduce the aircraft’s weight, a two-seater is envisaged to make a non-stop circumnavigation.
The Solar Impulse II landed in Hawaii on July 3, 2015, after breaking a five-day flight record and nights (117 hours and 52 minutes) in the air and about 8900 km from Japan. However, the long journey took its toll and the plane suffered damage to the battery due to overheating.
It remained grounded at the airport Kalaeloa during the northern hemisphere winter. Between February and mid-April, 13 test flights were conducted to ensure the proper functioning of the cooling system for the newly integrated battery.
Specifications – HB-SIA
Powerplant: 4 × electric motors, powered by 4 x 21 kWh lithium-ion batteries (450 kg), 7.5 kW (10 HP) each
Length: 21.85 m (71.7 ft)
Wingspan: 63.4 m (208 ft)
Height: 6.40 m (21.0 ft)
Wing area: 200 sq.m (2,200 sq ft)
Loaded weight: 1,600 kg (3,500 lb)
Max. takeoff weight: 2,000 kg (4,400 lb)
Take-off speed: 35 kilometres per hour (22 mph)
Cruise speed: 70 kilometres per hour (43 mph)
Stall: 35 km / h
Endurance: 36 hours (projected)
Service ceiling: 8,500 m (27,900 ft)
Maximum altitude of 12,000 metres (39,000 ft)
Crew: 1
