IOTL, in April of 2001, an American surveillance aircraft observing China was damaged in a mid-air collision with a Chinese interceptor off Hainan Island. It made a forced landing on Chinese territory, where the crew were held and interrogated for several days. Eventually the crew was released after the U.S. State Department issued a letter of apology.
What if the crew had not been able to land successfully and, instead, the plane crashed, killin everyone on board? Furthermore, what if the frantic last-moment communications heard from the crew led the Americans to believe that the plane had been shot down by the Chinese?