By Yereth Rosen
ANCHORAGE, Alaska (Reuters) - The pilot killed in a plane crash with former Alaska Senator Ted Stevens last summer should have undergone a more rigorous medical exam before getting his license back following a 2006 stroke, U.S. safety officials said in a report on Tuesday.
The National Transportation Safety Board said the pilot, Theron "Terry" Smith, may have been suffering some lingering effects from the stroke, which had led to a temporary suspension of his pilot's license and prevented him from flying for two years.
In its final report on the crash, issued in Washington, the NTSB found no clinical evidence that Smith suffered "a medical or cognitive problem" at the controls of the plane but cited that as a possible factor.
"A medical condition leading to transient incapacitation or impairment (of the pilot) could explain the circumstances of this accident," the agency said, adding, "it is not possible to determine whether such a scenario occurred."
Smith, who was 62 and a former chief pilot for Alaska Airlines, perished along with Stevens and three other passengers when the DeHavilland Otter aircraft he was flying slammed into a mountain slope on August 9, 2010.
The plane was carrying Stevens, the longest-serving Republican in U.S. Senate history, and a party of eight others back from a fishing lodge near Dillingham, Alaska, when it crashed.
The probable cause of the accident was listed simply as the pilot's "temporary unresponsiveness for reasons that could not be established from the available information."
Still, the NTSB faulted the Federal Aviation Administration for having reinstated Smith's license after his stroke without conducting a more thorough examination of the potential effects of his 2006 illness.
The report said it was "inappropriate" for the FAA to rely, as it did, on the in-office evaluation of a local neurologist in clearing Smith as healthy enough to fly again.
It said the FAA should have conferred with its own physicians or consultants to examine the issue further, including the likelihood of recurrence or extent of any remaining cognitive deficit.
The FAA revised its policy for such clearances several months before the accident, requiring an FAA doctor at agency headquarters to review a pilot's case before a field aviation examiner may renew a medical safety certificate for someone who suffered a stroke.
However, that requirement was not applied to Stevens because his stroke occurred years before the policy change.
In a statement responding to the safety board's report, the FAA said the agency "will now further examine certain types of strokes and possible precursors to see if we need to clarify our policy."
Smith was a highly regarded Alaska aviator with good health habits and a reputation for being careful, according to an earlier NTSB report. He also had served as director of the Alaska Aviation Safety Foundation.
Although his wife and some colleagues considered Smith fully recovered from his stroke, previously released NTSB documents revealed an incident from July 4, 2010, a month before the accident, in which he appeared to struggle to understand a hydraulic system that he had used many times.
He also had been stopped at least once after his stroke by a police officer who suspected him of impaired driving.
The plane carrying Stevens and his party hit the mountainside while executing a climbing left turn that the NTSB said was inconsistent with Smith's record as an experienced Alaska aviator.
(Editing by Steve Gorman and Jerry Norton)