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L-39 Best Glide Speed

The Flight Manual recommends 260 km/h for an engine out glide. However, looking at the charts, I'm seeing a best engine-out ranges (L/Dmax) to be around 290 km/h. Do any of you see this differently?

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2 Comments

  1. Thomas Proctor

    Jan. 2, 2018

    Hi Huggy Books I consult show best glide between 135 knots (250 km/hr) and 145 knots (268 km/hr) As a rule of thumb I teach best glide as 140 knots which is 260 km/hr which would validate that particular entry. Fly Safe Mongo

    1. Jon Huggins

      Jan. 3, 2018

      Thanks. If you're willing, could you drop me an email and let me know what other references you are using? I only have the translated Fligtht Manual. I think you have my email. My guess is the 260 km/h speed is based on the RAT being down. If my assumption is correct, a glide with the RAT retracted would have a higher L/Dmax airspeed. With the batteries we have in our jets, there should be no need for the RAT. Personally, I'd like to get rid of it and the weight.