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Operational Cost of Cabin Altitude Restriction (CAR)

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Technical Report,01 Aug 2016,01 Jan 2020

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711 HPW/RHMF Wright-Patterson AFB United States

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Conventional wisdom holds that cabin altitude restriction CAR ups risk for turbulencephysical stress on aircraft, prolongs flight times, and increases fuel consumption. As a result, systematic organizational resistance to CAR prescribing can be encountered. The Theater Validating Flight Surgeon TVFS often employs CAR to mitigate anticipated drops in tissue oxygen delivery recent studies demonstrate salutary clinical effect with appropriate CAR prescribing. This study aimed to ascertain the operational impact of CAR on Flight Duration and Fuel Cost. Operational flight data, from January 2005 through December 2015, were obtained from the 618th Air and Space Operations Center Tanker Airlift Control Center Data Division and matched to data from the Transportation Command Regulating and Command and Control Evacuation System. In this way, the operational flight data e.g., flight duration, fuel cost could be separated into CAR and Non-CAR missions. 8,191 missions were identified. Inaccurateincomplete data were purged. The result Flight Duration dataset n 5,561 and Fuel Cost dataset n 2,601. Flight Duration analyses revealed a universal drop with CAR, ranging 1.8 to 18.6 minutes. Fuel Cost analyses yielded mixed results CAR more expensive and operationally significant defined as 5,000 in Balad Air Base AB, Iraq to Ramstein AB, Germany C-17 route by 5,500 CAR more expensive, but operationally not significant for C-17 and KC-135 in Bagram AB, Afghanistan to Ramstein AB, Germany route CAR less expensive in Ramstein AB, Germany to Andrews Air Force Base, Maryland C-17 route. In sum, these findings do not endorse the conventional wisdom, especially when weighed against both clinical dollar and human savings. In fact, the CAR prescription did not up Flight Duration nor did it seriously increase Fuel Cost. Consequently, this study strongly argues against any embargo, or push back, relative to appropriate TVFS prescribing of the CAR.

Subject Categories:

  • Escape, Rescue and Survival
  • Medicine and Medical Research

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