The National Transportation Safety Board bogged down yesterday trying to apportion blame among the airport management, the Federal Aviation Administration, pilots and controllers for the World Airways DC10 crash in Boston Jan. 23.
Two of the 212 people on board are still missing and presumed to be the only fatalities in the accident, which occurred when World Airways Flight 30 from Newark slid off the ice-coated runway and into Boston Harbor while trying to land at Logan International Airport.
The accident came in a snow and ice storm only 10 days after 78 persons died in the Air Florida crash in a blinding snowstorm here. Those accidents have pointed to alarming gaps in the way the aviation system responds to such weather.
In debate that will lead to safety recommendations and a determination of "probable cause," the board made special note of these facts in the Boston crash:
* Several pilots on flights that landed on the same runway in the 30 minutes preceding Flight 30's attempt reported "poor" and, in one case, "poor-to-nil" braking conditions.Three other pilots who also landed reported nothing but told investigators after the accident that the runway was slick and that they had experienced trouble.
* None of those reports was relayed by FAA air traffic controllers to Flight 30, although its crew knew from recorded weather information that braking action was considered "fair to poor."
* The FAA requires that braking conditions be described as good, fair, poor, nil or some combination of those words. However, the FAA does not define those terms in manuals used by air traffic controllers or pilots, so the terms are subject to many interpretations. The military assigns runway friction conditions specific values based on instrument-derived measurements.
* The Massachusetts Port Authority's snow plan calls for runway inspections at Logan "when aircraft reports indicate poor braking." However, according to the board's staff, the MassPort supervisor on duty at the time of the accident did not reinspect the runway before the World flight's landing despite the braking reports from other pilots.
The board staff suggested that the failure to inspect the runway violated MassPort policy and represented "a willingness to accept risks to buy time." MassPort intended to close the runway after Flight 30 landed, the staff said.
William Coleman, director of aviation for MassPort, said in an interview that the FAA has set "no criteria" on when to close or reinspect a runway and that his supervisors were watching planes land and were aware of runway conditions.
* The FAA does not establish through testing the amount of additional runway needed to land safely on a wet or icy runway, a fact that has long been a major complaint of the Air Line Pilots Association. Instead, arbitrary safety factors are built into computations used by pilots in determining whether the runway is long enough.
* Although Flight 30's pilots operated the DC10 in a reasonable manner, there were other actions they might have taken that could have reduced the accident's severity, the staff suggested.
The plane landed too far down the runway at a speed somewhat faster than necessary. However, that speed was derived from an on-board computer the pilots had been instructed to obey. World Airways has since changed its speed instructions for contaminated runways.
The board is to continue its deliberations today.