Question: When was Umar Farouk Abdulmutallab attempting to detonate plastic explosives on Northwest Airlines Flight 253?
Related documents: [0]  [DOC] Umar Farouk Abdulmutallab (Arabic: عمر فاروق عبد المطلب ; also known as Umar Abdul Mutallab and Omar Farooq al-Nigeri; born December 22, 1986) popularly referred to as the "Underwear Bomber", is a Nigerian man who, at the age of 23, confessed to and was convicted of attempting to detonate plastic explosives hidden in his underwear while on board Northwest Airlines Flight 253, en route from Amsterdam to Detroit, Michigan, on Christmas Day, 2009. [END] 
[1]  [DOC] Northwest Airlines Flight 253 was an international passenger flight from Amsterdam Airport Schiphol in Haarlemmermeer, Netherlands, to Detroit Metropolitan Wayne County Airport in Romulus, Michigan, United States. The flight was the target of a failed al-Qaeda bombing attempt on Christmas Day, December 25, 2009, in which a passenger tried to set off plastic explosives sewn to his underwear. There were 290 people on board the aircraft—an Airbus A330-323E operated by Northwest Airlines, which had merged with Delta Air Lines the year before. Had the attempt succeeded, it would have surpassed American Airlines Flight 191 as the deadliest aviation occurrence on U.S. soil and tied Iran Air Flight 655 as the eighth-deadliest of all time. The incident was also the second in 2009 involving an Airbus A330, after the crash of Air France Flight 447 on June 1. This was also the final accident/incident involving Northwest Airlines as it closed down a month later when it merged with Delta Air Lines. [END] 
Answer: 
Christmas Day, December 25, 2009
Christmas Day, December 25, 2009