Plane Facts: Gliders

Derivation of the term "glider:" Unknown

Other common term for gliding: Soaring

Difference: In soaring, pilots gain altitude in flight

Glide ratio: Cessna 172: 9:1

Best high-performance sailplane: Better than 70:1

Northern flying squirrel: 2:1

Steinway Piano: Infinitely poor zero:1

Methods for altitude gain: Rising air (thermals), updrafts from terrain (ridge lift)

First claimed glider flight reports: Monks in England, around the year 1000

Reported distance of the flights: 200 meters

Likelihood of reports being true: About zero

First credible short glider flights: Around 1849, George Cayley

Aeronautical principles Cayley identified: Four forces (lift, drag, thrust and gravity), the cambered airfoil, dihedral and others

Pioneer of gliding: Otto Lilienthal

First flights: Germany, early 1890s

Launch pad: Man-made hill Lilienthal constructed for the purpose

Gliders Lilienthal designed: At least 15

Basis of most designs: Weight shift (like modern hang gliders)

Number of flights: Around 2,000

Year of death: 1896 in a glider crash

Early glider experimenters: Orville and Wilbur Wright

Popular class of glider post WWI: Primary glider

Basic design: Single-beam sit-atop fuselage, wings and tail

Appeal: Inexpensive and easy to build

How Germany developed pilots between WWI and start of WWII: Gliding Clubs

Number of Soviet pilots trained in gliders between the wars: 57,000

First motor glider: 1935, the Carden-Baynes Auxiliary

Various means of launching gliders: Bungees, foot launch, auto tow, plane tow, winch, motor launch

Various motor glider drag reduction methods: Retractable engine or foldable propeller

Low-drag option: Small jet engine

Largest glider: Space Shuttle, 2,030 tons

Largest military glider: Chase XCG-20, theoretically 70,000 pounds max weight

Highest operational weight: 40,000 pounds (limited by tow plane)

Lightest glider: Paraglider, as little as 10 pounds without harness

Cost of a (non-powered) paraglider: $1,000 and up

Highest glider flight: Perlan, more than 76,000 feet

Cost of Perlan glider: Approximately $1.5 million

Atmospheric conditions necessary for such high flight: Mountain waves plus polar winds

Indicated top airspeed of Perlan at 76,000 feet: About 40 mph

That figure corrected for conditions (true airspeed): About 280 mph

Longest hang glider flight (one-way): 475 miles, southern Texas to north Texas

Longest sailplane flight: 1,870 statute miles, South America, eastern Andes

Time to complete: 15-plus hours