Fred To is a solar pioneer, having designed and built the first solar-powered, human-carrying aircraft in a partnership with Aeronautical Engineer David Williams. Solar One flew on December 19, 1978, on what looked to be a misty English morning.
Solar One reunion with Fred To second from right, David Williams to the left of Fred
Over four decades later, today’s jaunt in Raphael Domjan’s SolarStratos was partly to celebrate Fred’s contribution to green aviation, but also to make a level-flight speed attempt.
Flyer magazine reports, “For Fred To, however, the September flight will provide a remarkable link between two generations of solar aviation – from a three-minute flight at Lasham in 1978 to the technology being developed for high-altitude solar flight today.”
SolarStratos’ press release shares Fred’s and Raphael’s thoughts about the occasion.
Fred To: “I am deeply touched to have been invited by Raphaël Domjan, an eco-explorer who believes in his convictions and dreams. This invitation to fly aboard SolarStratos represents an invaluable mark of recognition for me. I never imagined I would come to Switzerland to fly in a solar-powered aircraft. It’s incredible to see that thanks to Solar One, solar-powered flights continue to evolve. Thank you to Raphaël Domjan and to everyone who believes in solar energy.”
Raphaël Domjan: “It is an honor and a privilege to be able to invite Fred To aboard SolarStratos. He represents a role model for me. His perseverance, vision, and passion have always inspired me. Thanks to him, decarbonized aviation has been able to emerge. The entire SolarStratos team is happy and moved to be able to welcome this pioneer to the Payerne Homebase.”
As reported in your editor’s Kitplanes article, Solar One made two flights that December day. “The first, piloted by Ken Stewart, reached a maximum altitude of 59 feet, took off at 18 to 20 knots (20.7 to 23 mph), and topped out at 35 knots (40.25 mph). The second, flown by Bill Maidment, reached 42 knots (48.3 mph).”
The craft was powered by four small motors chained together and drawing current from 24 NiCad batteries fed by a small array of five-percent efficient solar cells.
The principles are the same for Solar One and SolarStratos, but the technology has evolved
The contrast between Solar One and SolarStratos could not be greater. Solar One had as many circular cells as the builders could afford. SolarStratos has 22 square meters (almost 237 square feet) of 20 to 24-percent efficient cells. The highly effective and light aircraft is a result of dedicated work by Calin Gologan and his firm, Elektra Solar GmbH.
These power the HP-50D motor and feed the lithium batteries. Tests this year will determine just how high they can take the German/Swiss craft.
Fred To took part in a level-flight speed run today in relatively calm air. SolarStratos’ best measured velocity so far is 136.6 kilometers per hour (84.88 mph). We’ll report on today’s result as soon as it is confirmed.
Technology advances, sometimes with astonishing speed. Fred To was there at the advent of a new imagining, and today was able to enjoy the current state of its art, courtesy of Raphael Domjan.