Updated: May 4, 2021
It is 30 minutes after midnight at Phoenix Sky Harbor International Airport in Phoenix, Arizona when the four-engined aircraft touches down gently and slows down to taxi speed. The aircraft is HB-SIA, Solar Impuls 1, the first solar-powered aircraft capable of flying day and night. It took off 18 hours and 18 minutes before from Moffett Field in Mountain View, California for the 747 miles flight. The photovoltaic cells in its wings charged the aircraft batteries which powered the aircraft at night.
It was the first leg of a total of 5 legs which would bring the aircraft to JFK Airport, New York. Each leg would last between 19 to 25 hours at speeds of about 35 knots.
Solar Impulse 1
The aircraft was designed to remain airborne for up to 36 hours. It conducted its first test flight in December 2009. In July 2010, it flew a 26-hour flight. Piccard and Borschberg completed successful solar-powered flights from Switzerland to Spain and then Morocco in 2012, and conducted the multi-stage flight across the US in 2013, of which the first leg is described above.
Some aircraft particulars:
Length: 71 ft 8 in (21.85 m)
Wingspan: 208 ft 0 in (63.4 m)
Height: 21 ft 0 in (6.40 m)
Wing area: 2,200 sq ft (200 m2)
Aspect ratio: 19.7
Gross weight: 3,500 lb (1,600 kg)
Max takeoff weight: 4,400 lb (2,000 kg) Take-off speed: 35 kilometres per hour (22 mph)
Powerplant: 4 × 10hp electric motors 21 kWh lithium-ion battery
Propellers: 11 ft 0 in (3.5 m) diameter11,628 photovoltaic cells rated at 45 kW peak: 200m2
Cruise speed: 43 mph (70 km/h, 38 kn)
Endurance: approximately 36 hours
Service ceiling: 27,900 ft (8,500 m) with a maximum altitude of 12,000 metres (39,000 ft)