Discuss as:

American Airlines: 'Gunk' partly to blame for loose seats

American Airlines says "coking": years of spilled soda, coffee and other detritus, is responsible for gumming up the locking pin that holds the seats to the floor. NBC's Tom Costello reports.

American Airlines has grounded dozens of airplanes for a second time this week due to loose passenger seats, causing nearly 100 flights cancellations on Thursday and Friday. It said it was quickly resolving the problem, which the company indicated was caused by an array of factors, including the “gunk” from drinks that get spilled. 

"We have identified the issue and our maintenance teams are securing an FAA-approved locking mechanism to make sure no seat can be dislodged,” company spokeswoman Andrea Huguely said in a statement. “Repairs are complete on 40 of the 48 aircraft. All of our (Boeing) 757s will be back in service by Saturday."

She said the seat issue forced the company to cancel 50 flights on Thursday, and 45 on Friday.

American first grounded the 48 Boeing 757 aircraft it operates on Monday for inspection after seats came loose on three flights, two of which made emergency landings as a result. 

Huguely’s statement did not provide detail as to what caused the seat problem, but another company spokeswoman, who spoke on condition of anonymity, said multiple “contributing factors” led to the problem.

“There are a lot of contributing factors — normal wear and tear, gunk that can affect the locking-pin mechanism—whether its debris or sodas,” she said.  

But she said “gunk” was not the primary cause.  “There were some installation issues—a lot of contributing factors.” 

Read the full story on NBC Travel

More content from NBCNews.com:

Follow US news from NBCNews.com on Twitter and Facebook

Follow Kari Huus on Facebook