Stabilized Approaches

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(image from http://en.wikipedia.org/wiki/Airbus_A380)
By Captain Shem Malmquist
There has been much emphasis on the importance of the stabilized approach.  I recently came across an interesting analysis of the time saved by flying an approach at higher speed as opposed to configuring early.  UPS pilots flew three simulated approaches in their simulator.  The time from the FAF to touchdown was recorded.  The FAF was 5.6 miles from the end of the runway.  The conditions were:
Flight 1: Fully configured and on speed at the FAF.
Flight 2: Typical approach speeds and stable at 1200 AGL.
Flight 3: Speed 250 knots to the FAF and not stable until 100’ AGL.
Following are the times from the FAF to touchdown:
Flight 1 = 2:30
Flight 2 = 2:20
Flight 3 = 2:02
That’s right!  The time “saved” by flying the very fast approach only saved 28 seconds as opposed to being configured and on speed at the FAF!
Granted, flying a bit faster seems to save time.  Perhaps that is more because the challenge of the late configuration keeps us more occupied.  However, the reason that the approach is more challenging is the same as why the approach increases the risk.  You are not doing yourself any favors by keeping your speed up!
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About Shem Malmquist FRAeS

B-777 Captain. Air Safety and Accident Investigator. Previous experience includes Flight Operations Duty Officer, Assistant Chief Pilot. Line Check Airman, ALPA Aircraft Technical and Engineering Chairman, Aircraft Performance and Designs Committee MEC Chair, Charting and Instrument Procedures Committee, Group Leader-Commercial Aviation Safety Team-Joint Safety Implementation Team (CAST)-Loss of Control-Human Factors and Automation, CAST-JSIT- Aircraft State Awareness. Fellow of the Royal Aeronautical Society, full Member of ISASI, AIAA, IEEE, HFES, FSF, AFA and the Resilience Engineering Association.
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