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Do gliders (sailplanes) use ridge and wave lift in the Himalayas to go to extreme altitudes, possibly above Everest's peak?

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Do gliders (sailplanes) use ridge and wave lift in the Himalayas to go to extreme altitudes, possibly above Everest's peak?

Yes, there are gliders touring Himalayan peaks over 8,000m, including Annapurna and Everest, using mountain waves. Montain waves differ from ridge waves as they are created on the leeward side of the mountain. They can be flown without being close to the relief.

Gliders over Himalayas

Example with this Stemme S10VT motorglider:

enter image description here

The image is extracted from an advertising page of the company doing this business. The glider has a service ceiling of 9,140m. Flight is done with oxygen masks in a non pressurized cockpit.

Video on Youtube. From the video:

enter image description here

Mountain waves

These flights are linked to the Mountain-Wave-Project, initiated by René Heise and Klaus Ohlmann, both glider pilots, the latter was the first pilot to glide over Everest. Mountain waves are air layers trying to stabilize after they are disturbed by relief:

Mountain waves

producing these beautiful lenticular clouds:

Lenticular clouds over Les Druts

Lenticular clouds over Alps, source

Stratospheric mountain waves

Mountain waves are a strong lift source. Using stratospheric mountain waves, Airbus reached 23 km with two pilots onboard a Windward Performance Perlan II, surpassing U2 record*:

Airbus Perlan II mission

Airbus Perlan II mission, source

Absolute altitude versus height gain

Flying at high altitude is not the biggest problem for a glider. You may start a bit below, gain a few altitude, and claim 6,000 m or 8,000 m. Any commercial airliner is able to glide from its cruise level, about 10-11 km. This is not soaring, that is using wind to gain altitude.

Gaining altitude requires specific skills, a good knowledge of winds, a favorable location and a great deal of cooperation from the weather. Not all gliders are equal, those made for high altitude may fly poorly at low altitude. There are glider categories to file a record at FAI because performances depend on the wingspan to extract lift.

  • The record for gain of height is 12.9 km. It was set in 1961 and, according to Wikipedia never outdone in 60 years.

  • In contrast altitude records were set over years, and Perlan II was able to fly at 23.2 km in 2018, but the glider was towed up to 12.2 km (40,000 ft) by a turboprop aircraft (tow release video) and from the narrative of the flight, there was no way (in this particular instance) to reach 12 km without being towed.


*Humor. U-2 record is here.

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    $\begingroup$ Just for clarification: 9140 m are 30,000 ft and 23 km are 75,500 ft. $\endgroup$
    – Giovanni
    Sep 14 at 14:48
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    $\begingroup$ Wow I thought there was only going to be a pithy answer of "yes, the space shuttle" $\endgroup$
    – llama
    Sep 14 at 18:28
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    $\begingroup$ @llama while it may technically qualify as a glider on descent, highly polished bricks falling with style aren't really what most people have in mind when they think of gliders. And in any event, the shuttle had essentially zero chance of ever gliding over the Himalayas; except for the remote possibility of an emergency landing the Shuttle always would reenter the atmosphere thousands of km farther East. $\endgroup$ Sep 14 at 18:51
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    $\begingroup$ This answer is missing to mention the fact that any glider can fly at those heights. For decades the height record was at 15,000 metres (50,000ft) on a Grob G102 Std, a trainer glider. Way way higher than Everest. The big issue with flying at extreme heights is the need of more sophisticated oxygen equipment, the cold, and the coffin corner. $\endgroup$ Sep 15 at 6:31
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    $\begingroup$ The most surprising fact is that it seems that you can glide over the Everest without being intercepted by Chinese fighters. $\endgroup$
    – Pere
    Sep 15 at 12:57

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