Density Altitude

Discussion in 'Pilot Training' started by George Foster, Feb 6, 2019.

  1. George Foster

    George Foster Filing Flight Plan

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    Hi, we all know the rules and issues related to high altitude flying.

    Here is my question: If you depart an airport at sea level on a hot Summer day, and the density altitude is 2000 feet, and you climb to 10,000 feet, are you effectively at 12,000 feet?
     
  2. dmspilot

    dmspilot En-Route

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    No, it would depend on the temperature at your altitude.
     
  3. George Foster

    George Foster Filing Flight Plan

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    Of course. I should have known that. Thanks
     
  4. midlifeflyer

    midlifeflyer Final Approach

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    Understandable error. In training, we definitely talk about calculating density altitude on the ground more than at altitude. That's because density has a substantial impact on takeoff and landing performance and distance. It has its performance effects at altitude also but the practical takeoff and landing issues it creates are far more critical.

    At altitude - service ceiling, airspeed, and fuel flow.
    Takeoff and landing - engines quitting on takeoff, stalls on takeoff, wheelbarrow landings, and running off the ends of runways.

    (No, those examples are not intended to be all-inclusive)
     
  5. Clip4

    Clip4 En-Route

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    Except the altimeter setting has a larger effect than temperature reduction as you ascend.
     
    Last edited: Feb 7, 2019