Ridge lift

Orville Wright used ridge lift, setting a duration record of 11 minutes in 1911.

In 1921, Dr. Wolfgang Klemperer broke the Wright Brothers’ 1911 soaring duration record with a flight of 13 minutes.

[1] In 1922, Arthur Martens became the first glider pilot to use an updraft rising along a mountain slope to stay aloft for a lengthy period, with a flight over an hour.

Downwind of the hill, lee waves can form; these are also used by glider pilots to gain height, but this should not be confused with slope lift.

Long mountain ranges such as those found in Ridge-and-valley Appalachians in the United States, New Zealand, and Chile have been used by glider pilots to fly in excess of a thousand kilometers in a single flight.

Ridge lift at Torrey Pines Gliderport in San Diego, CA
A Scimitar glider ridge soaring in Lock Haven, Pennsylvania USA
Diagram of a slope with the zone of rising air in pale green