Lengthening calculated landing and takeoff distance to ensure safety in bad weather will be the focus of a new US FAA review.
An Aviation Rulemaking Committee (ARC) will be convened to review certification and operating rules governing the minimum acceptable runway lengths for takeoff and landing. The review will focus on runway conditions that are contaminated by snow, slush, ice, or standing water.
Pressure to review the rules came from the US National Transportation Safety Board (NTSB), recommending in October that the agency “immediately” mandate a 15% safety margin to be added into the runway landing distance calculations in the wake of a deadly Southwest 737 runway overrun at Chicago Midway Airport in December 2005.
Though the NTSB concluded that the probable cause of the accident was the pilots' failure to use thrust reversers "in a timely manner", investigators found that the distance calculation the pilots made before arrival on Southwest-provided portable laptop computers did not include actual wind conditions and other factors critical to making their decision.
The FAA in the immediate aftermath of the accident published a safety alert asking operators to voluntarily institute the change, and planned to ultimately follow up the alert with a rulemaking depending on the outcome of the ARC.
The NTSB said 27 of 65 carriers who responded to an FAA questionnaire about the alert had reported adopting the 15% safety margin in full and 22 had said they adopted the changes in part.
The FAA says the ARC will be responsible establishing certification and operational requirements, including training, for takeoff and landing operations on contaminated runways, coming up with landing distance assessment requirements, including minimum landing distance safety margins to be performed at the time of arrival, and establishing standards for runway surface condition reporting and minimum surface conditions for continued operations.
- Southwest 737-700 overruns
- Midway to install runway arresters
- December 2005 Southwest Chicago blizzard accident leads US NTSB to urge for revised landing margin policy on contaminated runways