I know that light aircraft have poor glide ratios (typically 1:10) compared to commercial aircraft (typically 1:20 or above). I was wondering if there is a source where one can find the glide ratio by aircraft type.

I am particularly interested in the BA146 / RJ85 following the LaMia crash in Colombia.

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    $\begingroup$ The glide ratio is likely similar to the lift/drag ratio, though actual mass may have an impact on the glide ratio. A B747 wing has a L/D ratio of 17.7. I suspect that there are tables used to compute the continuous descent approach that would fit your need. $\endgroup$ – mins Dec 1 '16 at 20:08
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    $\begingroup$ Related, regarding 787 glide ratio $\endgroup$ – fooot Dec 9 '16 at 18:20
  • $\begingroup$ 20 is an extremely good ratio for an airliner. Nearly all of them have it under 20, with perhaps a few exceptions which may have it marginally higher (787 may be amongst them but it's hard to be sure). $\endgroup$ – Zeus Dec 13 '16 at 5:27

The glide ratio is closely related to the lift/drag ratio; as lift/drag ratio is closely related to aerodynamic performance, aircraft manufacturers are very restrictive on such data and little reliable information is publicly available. Some guesses can be made from incidences like Air Transat Flight 236. For the A330 this results somewhere around 24.

I'm not aware of any data on BA146/RJ85. As BA146/RJ85 focusses on short haul it may have a slightly lower glide ratio; 4 engines are also not favourable for a sailing plane. Still anything below 20 would be a surprise to me.

Edit: Seems I sort of mixed up the numbers. The A330 should be somewhere over 20 (quite a time since I worked on that...). Fopr the RJ85 on this forum the glide ratio is estimated as 15:1.

P.S.: Keep in mind that all these values are maximum values that can be reached under optimal conditions. Real values may be lower.

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    $\begingroup$ Air Transat flight 236 needed to glide 120 km and had at least 10 km of altitude at the moment the second engine flamed out. That is glide ratio of mere 12! The plane is capable of more, but the actual value is somewhere between 18 and 20. 24 is too much for a transport jet. $\endgroup$ – Jan Hudec Dec 10 '16 at 22:01
  • $\begingroup$ ... and Ba146/RJ85 is a rather old design. I would expect less than 18. $\endgroup$ – Jan Hudec Dec 10 '16 at 22:05

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