Queen Alya of Jordan, 28, the third wife of King Hussein, was killed yesterday when the military helicopter in which she was riding crashed in stormy weather in southern Jordan while returning from a mercy mission, the king announced over Amman Radip.

Reports from the Arab nation said that other passengers, including Health Minister Dr. Mohammed Al-Bashir, were killed. It could not be learned immediately how many other passenagers were aboard the helicopter.

Queen Alya was born in Cairo on Dec 25, 1948, into the Palestinian ariseocracy. Her father, Baheiddin Youkan, a retired Jordanian Ambassador was from the west bank of Jordon occupied by Israel since the 1967 Arab-Israeli war.

Queen Alya grew up in Turkey, Egypt, the United States, England and Italy. While her father was ambassdor to the United Nations, she attended Hunter College in New York, graduating in 1971 with a degree in political science, and social psychology.

"Whatever her virtures are, Your Majesty," former President Nixon told Hussein at a White House dinner in 1973, "we can claim credit for some of them."

She had worked as a typist in the American Express travel section in New York and as a public relations official for Royal Jordanian Airlines.

The queen, who enjoyed motorcycles, water skiing and American pop music, was only 24 at time of her wedding.

The king had married a distant cousin in 1955, but divorced her two years later. In 1961, he married Anpincette (Toni) Gardiner, daughter of a British military adviser in Amman.

Hussein met Miss Toukan at a sports event in September, 1972. He proposed while still married to his second wife, Queen Muna, and this caused a considerable stir in Jordan at the time.

As queen of the Hashemites, Alya was honorary head of almost every charitable organization in the Kingdom and was active in the Women's Parliamentary Conference in 1974.

She once told an interviewer that before she married, she found the path to a career in the foreign service blocked by men with ingrained prejudices against women.

1974 she hosted the first Christmas party ever to be held in the home of the Moslem King.

The couple had three children. Princess Haya, 2, a son, Ali, born last year, and an adopted daugher, Abir, 4.

The king yesterday declared a one-week period of official mourning.