WASHINGTON -- The difficult search for answers about the disappearance of Malaysia Airlines flight MH370 is compounded by the inability to find either the plane intact or the wreckage.
Malaysian officials said in an emotional press conference they believe the plane crashed into the Indian Ocean.
As authorities try to figure out where the wreckage is and why it crashed, manufacturer Boeing has all but ruled out a cyber-attack on the plane.
"We won't engage in speculation regarding this event," said Boeing spokeswoman Gayla L. Keller in a statement to WTOP on Monday, March 24.
"We are confident in the robust protection of all flight critical systems and inability for a hacker to gain access by either external or internal means on the 777 and all Boeing airplanes."
WTOP reported on March 14 that Boeing was concerned about the possibility the plane's systems could be hacked and previously contacted the Federal Aviation Administration.
On Aug. 21, 2012, Boeing applied for permission to change the equipment to be installed as part of an on-board data network system upgrade on the 777 series of planes.
According to information listed in the Federal Register the existing "data network and design integration may result in security vulnerabilities from intentional or unintentional corruption of data and systems critical to the safety and maintenance of the airplane."
According to language in the Federal Register:
"The integrated network configurations in the Boeing Model 777-200, -300 and -300ER series airplanes may enable increased connectivity with external network sources and will have more interconnected networks and systems, such as passenger entertainment and information services than previous airplane models. This may enable the exploitation of network security vulnerabilities and increased risks potentially resulting in unsafe conditions for the airplanes and occupants."
In November 2013, special conditions were approved allowing Boeing to make changes on the 777 planes.
It's not clear whether all security upgrades to planes are complete. As investigators dig into what happened to the plane, a check of publicly available flight records for the missing aircraft identified as MSN 28420 - 9M- MRO, raise a key question about the plane.
The records indicate the plane flew the day before, March 7, from Beijing to Kuala Lumpor. But it appears the plane may have been out of service for an extended period of time prior to its flight on March 7.
"Either they were in a severe economic crunch or it was down for maintenance, because they try to keep those things in the air constantly," says Oliver "Buck" Revell, former Deputy Director for Operations for the FBI. Revell is also a licensed pilot and flight instructor.
According to flight log documentation, the plane was possibly out of service for more than a month before its March 7 flight.
Aviation experts say while a 777 aircraft is in flight, information is collected about the performance of the plane including any concerns. When it lands those concerns are addressed -- quickly.
"You have a real community of interest that is swarming over that airplane because of the quick turn around a lot of times," says Billy Vincent, former Federal Aviation Administrator.
Vincent says quickly cleaning and maintaining planes and getting them airborne again is important to airlines' revenue streams, but security is supremely important.
"Every method is taken to make sure that there is no unauthorized foreign item left in the passenger cabin or the cargo bay or the avionics bay or anything else on that airplane."
But it's the need for speed in airplane turn-around that has raised concerns among some investigators that perhaps something was overlooked in the clean-up or maintenance process.
Without debris to probe, Revell says investigators will have to rely on the basics to figure out what happened.
"Were there any threats, had there been any indications that there would be any problems, you want to look at the passenger manifests to see if there were any individuals on there that had significant problems with the airline or association with any known terrorist group or criminal cartel," are the main questions, says Revell.
But in this case, he says the most important aspect is "to look at the aircraft maintenance record itself."
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