TECHNOLOGY FOR THE FUTURE: SOLAR-POWERED AIRPLANES

Solar Impulse is building a solar-powered airplane with the goal of flying around the world. It will be registered as HB-SIB. The HB-SIB follows the first Solar Impulse prototype solar-powered airplane that is registered as HB-SIA, and completed the world’s first solar-powered intercontinental flight in July 2010. The HB-SIA contains four 10-horsepower engines that are powered by 12,000 solar cells that are installed on its wings. It is capable of flying without fuel during the day and at night.

Construction of the HB-SIB began in 2011. Taking what Solar Impulse engineers learned from the prototype HB-SIA, Solar Impulse is constructing the HI-SIB larger with a roomier cockpit area so that the pilot can recline during its around the world flight. The flight is an estimated to take about 1000 flight hours and expected to last 4 to 6 days.

Some of the existing technology used to make the materials and components that were used in the HB-SIA are being used in the HB-SIB. Because of the duration and conditions of the planned flight, new technology has been developed for use in the HB-SIB including electrolytes that can increase the batteries energy density and lighter weight carbon fibers. A pressurized capsule is being incorporated into the airplane as well as better electronic systems that control components such as communication and navigation.

Another technology that is being installed in the HB-SIB is called a Monitoring and Alerting Subsystem, MAS. That subsystem is new technology that has never been on the market. The pilot will wear an electrodes patch when flying the airplane. The patch will vibrate the pilot’s arm and notify the Mission Control Center if anything out of the norm occurs during the flight. The MAS is being incorporated into the Stabilization Augmentation System, SAS. The SAS is also being designed especially for the HB-SIB in order to calibrate the specificities in the solar airplane.

Flight-testing of the HB-SIB’s was planned for the spring of 2013 and its flight around the world was planned for mid-2014. On July 5, 2012, during the HB-SIB’s structural test, the wing spar cracked and the test failed. The engineering team is currently conducting tests and analyses to determine what caused the failure. The spar will have to be rebuilt which will cause a delay in the planned flight schedule. Solar Impulse has stated that 2015 is a more realistic deadline to plan for the flight around the world.

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Peter Wendt is a freelance writer/researcher working from his home in Austin, TX. He is in the process of getting his house off the grid and is interested in the latest advances in solar technology. Wendt recommends his readers visit Build Native for more information.