While the turboprop plane that crashed in Clarence last week has a relatively good safety record in the United States, the plane has a history of mechanical problems that have caused concern around the world.
Until the Clarence crash, nobody had been killed while on board a Q400.
But there have been some close calls, many involving the plane's landing gear.
In Japan, officials demanded safety improvements to the aircraft after an incident in March 2007 in which a Q400 made an emergency landing in Kochi after its nose landing gear failed to descend. The plane skidded down a runway on its belly, sending off showers of sparks. All 60 passengers got off safely.
In Europe, Scandinavian Airlines grounded its fleet of Q400s in 2007 after emergencies related to landing gear on three different planes within 45 days in Lithuania and Denmark. In one case, the plane's landing gear crumpled.
From Scotland to Portland, Ore., and from Pittsburgh to Australia, problems with the Q400 have ranged from icing to instrument failure to an explosion of a tail compartment prior to takeoff, in addition to the landing gear issues.
Now, in the wake of the Clarence crash that killed 50 people, officials at the National Transportation Safety Board said this record of incidents will factor into their investigations into what caused Continental Connections Flight 3407 to plummet to the ground last week.
So far, investigators have discussed icing on the plane's wings, as well as possible pilot error, as reasons for the crash.
The landing gear of the plane is also under scrutiny, safety board officials confirmed.
"That weighs in as part of the investigation," said NTSB spokesman Keith Holloway. "We are looking at all aspects of the aircraft. We are looking at maintenance, mechanical issues, aircraft structure, the airframe."
In particular, he said, investigators will be looking for "stresses on the metal, any indication of failure in the metal."
At Bombardier, the Montreal-based company that makes the Q400, executives continued to defend the aircraft, which is viewed in much of the aviation community as a "workhorse" model able to fly and land in all sorts of conditions.
Today, 219 of the Q400s are flying around the world, about one-fourth in the United States, said Bombardier spokesman John Arnone.
The model debuted in 2000 and has logged 1 million flying hours and 1.5 million takeoff and landing cycles, "virtually incident-free," Arnone said.
"The Q400 has an exemplary safety and support record," he said.
Some experts agree.
"These are mechanical [occurrences]. These things do happen," said Fred Mirgle, chairman of the aviation maintenance science department at Embry-Riddle Aeronautical University. "They do not affect the overall safety of the plane."
Other experts said the plane's mechanical history is cause for concern, especially in light of the Clarence crash.
"[Investigators] will look very carefully at what happened with the loss of control of the airplane. And the landing gear descending is one of the things that happened right before the loss of control," said John Hansman, director of the International Center for Air Transportation at the Massachusetts Institute of Technology.
"If there was a problem with the landing gear that somehow impacted the aircraft's handling qualities, that could be a problem," Hansman said.
The Buffalo News analyzed incident reports for the Bombardier Q400 aircraft dating to the plane's introduction in 2000. The reports were gathered from authorities in Canada, which collects information on Q400s from around the world because the plane is made in the country. The News also reviewed reports from the Japanese government.
U.S. records filed with the Federal Aviation Administration showed that the Q400 plane involved in the Feb. 12 crash had no prior accidents or serious incidents.
Throughout the United States, there were 11 reports filed with the FAA about other Q400 planes. Worldwide, there were 80 such reports.
The News review found:
*Twenty-two percent of the occurrences -- more than one in five -- with Q400 planes involved landing gear malfunctions or failures. In some cases, the problems were severe enough to warrant emergency landings and complaints from governments and airlines about the planes. In other cases, the problems were less severe, and involved problems with lights or hydraulic systems.
*Two of the reports involved icing on planes. In Edinburgh, Scotland, a plane taking off in December 2006 had icing problems and some failure in its instruments; the plane landed safely. In March 2008, a plane in Canada experienced vibrations on both propellers, believed to be due to icing.
*Eight reports centered around engine problems. In a few of those cases, the plane's engines lost power or shut down during flight.
*A few of the incidents remain under investigation. In Portland, a pilot preparing for takeoff in March 2007 reported an explosion coming from a compartment at the tail of the plane. The 74 passengers were unhurt.
Other reports detailed incidents involving bird strikes and mechanical problems with other parts of the plane.
At Bombardier, executives said that problems with the landing gear were fixed after the string of incidents with Q400s in 2007 -- one in Japan, and three in Northern Europe.
"The company shortly after the first incident [in 2007] initiated a regimen for all operators to inspect the aircraft," said Arnone. "The provision was for an inspection, and then, if necessary, a replacement and repair."
All new Q400s are made with safer landing gear, the company said. The plane, which sells for $26 million, is assembled at Bombardier's Toronto plant from parts manufactured all over the world, including China, Mexico, Ireland and England.
The Q400 plane that crashed in Clarence was built in 2008, according to FAA records.
However, The News review of the accident and incident data reports from around the world showed that 11 reports about landing gear problems were made in 2008 and 2009, after the problems were presumably fixed.
In Japan, scrutiny of the Q400s continues after problems with the planes were reported, including a 2005 incident where white smoke filled the aircraft, forcing an emergency landing, and a 2004 incident where a plane slid off a runway.
In the 2007 Kochi incident, the plane's nose landing gear failed to deploy because the door did not open, according to a 2008 report by Japan's Aircraft and Railway Accidents Investigation Commission. Investigators blamed a missing bolt.
But a Japanese reporter who has been part of an investigative team at the Kochi Shimbun newspaper said that public reaction to the accident was intense -- and heightened, after the crash of Flight 3407 in Buffalo.
"People's impression was very emotional," said Kazuhiro Ike, who flew to Buffalo to cover the crash. "They think very seriously about the Q400s safety problems. They think, are we guinea pigs?"
Mirgle, at Embry-Riddle, said that landing gears on planes take a beating -- "landing gear catches hell," he said -- and that might explain the number of occurrences with the Q400.
If the crash in Clarence hadn't happened, he added, the landing gear on this model plane would probably never come under scrutiny.
"There are a number of landing gear problems with all airplanes," Mirgle said. "We just don't know about them."