Sailplane-Like Boeing Cruises on SUGAR

Dean Sigler Electric Powerplants, Hybrid Aircraft, Sustainable Aviation Leave a Comment

Boeing has sustained a decade-long program to develop aircraft that reduce the use of fossil fuels or eliminate it altogether.  SUGAR (Subsonic Ultra Green Aircraft Research) program designers have resorted to configurations that were a part of early high-performance sailplanes, those craft that soar on the energy of the very air around them. Sailplane designers know that longer wings give a lower span loading: the weight of the airplane and its payload is spread over a greater span.  On powered craft, low span loadings give greater rate of climb for the same power and enable throttling back to get the same cruise speeds.  Longer spans usually lead to heavier structures, though.  Spars end up weighing more and wings are subject …

Jetstream Cargo Gliders – Colorado to China in Three Days

Dean Sigler Electric Powerplants, Hybrid Aircraft, Solar Power, Sustainable Aviation Leave a Comment

Just as Richard Starke was explaining to Experimental Soaring Association attendees at this year’s Western Workshop how his proposed stratospheric cargo glider program would work, some multi-tasker checking his tablet shouted, “Perlan’s reached 76,000 feet!” Richard’s concept of launching cargo gliders that would ride the jet stream between continents was suddenly validated before an audience that a few minutes before might have been dazzled and even skeptical of his proposal.  Perlan’s tows behind the recently recruited Grob Egret turboprop towplane made 10,000 feet in 10 minutes a time-to-climb reality, and tows to 40,000 feet allowed rapid exploration of developing air masses over the Patagonian mountains. The idea of flying large, cargo-carrying gliders goes back to at least Word War Two, …

Tehachapi 2013 – Baby Bowlus and Silent Electro

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

Tehachapi is a one-time railroad stop, 4,000 feet in the high mountain desert near Mojave, California.  Trains don’t stop there very often these days, but multi-engined, two-mile-long bearers of cargo and commerce run over the tracks 50 times a day, making the long haul toward Bakersfield or Mojave. Hawley Bowlus helped build the Spirit of St. Louis and later taught the Lindberghs to fly sailplanes, with some lessons taking place in the high desert air above Tehachapi.  Today, the once bare hills are covered with over 5,000 wind turbines, their giant rotors pointed into the prevailing westerlies.  At the base of these hills, Mountain Valley Soaring has a base, and Jeff Byard has a hangar that hosts the annual meeting …