Federal transportation safety recommendations are receiving renewed scrutiny in the wake of a plane crash Thursday night near Buffalo, N.Y., that killed 50.
The National Transportation Safety Board published a report in November calling on the Federal Aviation Administration to shore up airline safety regulations and procedures, including measures to improve the de-icing of airplanes.
Federal investigators continue to sift through the wreckage of Continental Airlines Flight 3407, which was carrying 44 passengers, four crew members and an off-duty pilot when it crashed into a house in Clarence, N.Y. — killing all aboard, as well as one person on the ground. An official described the scene to reporters Saturday afternoon as an "excavation," with the plane wreckage mingled with the house and human remains.
The year-old Bombardier Q400 aircraft may have crashed because of icy buildup on the plane's wings, according to the plane's "black box" flight recorders found at the site.
"The NTSB has been concerned about icing really since the 1990s, when there were two very difficult accidents," former NTSB Managing Director Peter Goelz told FOX News on Saturday, noting the agency's recommendations to the FAA.
"I think the NTSB feels that the FAA has not acted fast enough," Goelz said.
The FAA has responded to such concerns by posting a fact sheet on its Web site outlining the actions it has taken to address the problem of icing conditions.
Some of the NTSB's recommendations for the FAA are included in its 2009 "Most Wanted List" of transportation improvements, released in November.
The NTSB suggests new research on plane design, revisions to de-icing guidelines and more aggressive use of certain safety devices. For all of the items on the list, the FAA's response was deemed "unacceptable" by the NTSB.
The industry has been hit hard financially in recent years by the terrorist attacks of Sept. 11, the economic downturn and rising fuel costs, but upgrading the de-icing of planes is "an expense that really cannot be put off," Goelz said.
FAA spokeswoman Laura Brown told FOXNews.com that the agency already is addressing the issues raised by the NTSB.
"My understanding is their primary concern at the time was we weren't doing things quickly enough," she said, but because of the lengthy review and revision process, rules and regulations can't be changed overnight.
Brown also noted that, because the plane that crashed Thursday was relatively new, it already had some of the latest technology that the NTSB is recommending for all aircraft.
The crash Thursday was the first deadly crash of an American commercial aircraft in 2 1/2 years. The fiery scene was a grim contrast to the January crash-landing of a U.S. Airways jet in the Hudson River. Everyone onboard that plane survived the crash, which was blamed on birds striking the engines.
Click here to read about prior trouble with the type of jet involved in the crash.
Steve Chealander, spokesman for the NTSB, said Saturday that the icing is just one of several possible causes under investigation in Thursday's crash, the Associated Press reports.
He said the NTSB had been pushing for better de-icing regulations "for several years."
Chealander later updated reporters on the status of the investigation, saying that it appears that the plane landed flat on the house — rather than nose down, as witnesses have said. And the configuration of the wreckage also suggests that the plane was facing northeast, in the opposite direction of the runway where it was about to land, Chealander said.
The NTSB said it could be three to four days before all victims will be removed from the crash site. Many relatives of the victims are staying at a nearby hotel as they await answers.
PHOTOS: Crash Scene | Victims
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