O'Grady said US Airways has failed to find the ashes or explain how they were lost.
"US Airways, rather than Mr. and Mrs. O'Grady, has had the last word in determining Mr. O'Grady's final resting place," the lawsuit reads. "He is not at peace."
Before Brian O'Grady died in October 2011 at age 71, his wife pledged that she would scatter his ashes in Hull, England.
On Nov. 1, 2011, she went to Philadelphia International Airport to fulfill his wish, but when she reached TSA security, agents told her she couldn't take the cardboard box that contained a plastic urn of her husband's ashes in her carry-on because "its contents were not a solid substance," according to the suit.
O'Grady returned to the US Airways desk with her baggage-claim ticket so the ashes could be placed in her checked luggage, the suit said.
By the time O'Grady got to her gate, she was told she was late and that she'd given up her seat, said her lawyer, Bill Goldman Jr. He said she was required to pay $500 to upgrade to first class to stay on the same flight that she thought her husband's ashes were on.
Although her bag arrived in England, O'Grady claims the remains weren't in it.
Goldman said US Airways' response to O'Grady's inquiries and his requests has been to "Ignore, ignore, ignore."
US Airways spokesman Andrew Christie provided a statement to the Daily News:
"While we certainly send our condolences to Mrs. O'Grady, US Airways' investigation into this matter did not uncover any information indicating that US Airways is responsible for this unfortunate incident," he said. "We, of course, will defend ourselves against this suit."
Goldman said he wants to know what kind of investigation US Airways conducted into the incident.
"To merely say that our investigation did not reveal anything is inadequate and it's an insult," he said.
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