WASHINGTON -- The National Transportation Safety Board blamed a Republic Airlines pilot and airport authorities Friday for a January accident in which a broken propeller blade sliced through the cabin and killed a passenger.
Although the board report cited several contributing factors, it concluded the probable cause of the Jan. 9 accident in Brainerd, Minn., was 'the failure of the captain to properly align the airplane with the runway in sufficient time to allow a touchdown with no drift and the position of a snowbank on the edge of the runaway -- the height of which exceeded that specified by regulation.'
At the controls of the twin-engine Convair 580 was Capt. Henry Didier, 32. The co-pilot was Daniel Fry, 31.
The aircraft landed right of the runway center and drifted to the right where the propeller on the right engine hit the snowbank, shearing off two of the four blades. One ripped into the cabin, severing both legs of a 68-year-old woman who died aboard the plane of blood loss. A 6-year-old girl whose right leg was severed survived.
The safety board said contributing causes were 'the intensity changes of the runway lights and snow-covered terrain, both of which affected the captain's visual landing perception. The absence of a Notam (Notice to Airmen) on the control of the airport lighting system and the failures of the airport management and the company station manager to report the location of the snowbanks to the flightcrew also contributed to the accident.'
The board said the snowbanks did not confirm to federal position and height rules and because the airport manager had elected to wait until Jan. 10 to blow them fully out of the way, the manager should have immediately asked the Federal Aviation Administration to warn pilots about the condition of the runway and the position and height of the snowbanks. Such a warning was not issued until the day after the accident.
Four members voted to adopt the report unanimously, but member Patrick Bursley did not agree on the probable cause.
'Given the airplane's alignment upon landing, there would have been an accident in any event,' said Bursley. Thus, he said he regarded the presence of the snowbanks to have 'affected the severity of the accident rather than cuased the accident.' Bursley said the pilot realized he was improperly aligned with the runway in enough time to make a go-around, so the factors cited by the others as contributing to the accident were not in fact causes of the accident.
In its analysis of the accident, the board said the position of the snowbanks blocked some runway lights and the pilot may have lost peripheral vision at touchdown, but it concluded that because of the way it was landed the plane would have run off the runway even if the snowbank was in the right place.
The board's report also said the co-pilot dimmed the runway approach lights by radio from the cockpit but the crew did not know that when that was done the runway edge lights also dimmed.
A notice should have been issued, it said, because 'the dimming of the lights could have made the runway lights seem father away creating the illusion that the airplane was higher than it actually was, especially if the pilot was not aware that the intensity of the lights had been reduced. Thus, the captain may have landed before he expected to, and he may have thought he had more time to align the airplane with the runway.'
The aircraft, flight 927, was on a regular flight from Minneapolis to Thief River Falls, Minn., with stops at Brainerd and Bemidji. The accident occurred in light snow snowers and fog. Clouds were down to 300 feet and visibility was put at one mile. There was about an inch of snow and slush on the runway.
According to the NTSB report, the plane touched down on runway 23 about 1,700 feet past the threshhold of the 6,500-foot runway. The aircraft, with its right wing down, landed to the right of center of the 150-foot-wide runway and continued drifting to the right until the right propeller hit a two- to three-foot-tall snowbank between the runway edge and the runway lights. One blade on the four-blade prop separated and entered the cabin, killing one of the 30 passengers and three crew aboard and seriously injuring a second passenger.
The propellers on an Convair 580 clear the ground by just 12 inches.
