The WNBC employees were trapped for several minutes in the submerged helicopter, which went down at 4:45 p.m. EDT during the height of the evening rush hour.
City scuba divers finally pulled the occupants from the helicopter, and rescuers worked at dockside to revive them.
Late last night, after several hours in the emergency ward of Bellevue Hospital, Pate was taken to surgery for internal bleeding. He was listed in critical condition.
A St. Vincent's Hospital spokeswoman said Dornacker's heart had stopped and there was no brain activity when she was pulled from the water by frogmen.
"The patient arrived at St. Vincent's Medical Center in cardiac arrest with no evidence of brain activity despite all efforts of resuscitation," said spokeswoman Caroline McBride. "After prolonged efforts of further resuscitation, the patient expired at 8:22 p.m.," she said.
Dornacker was broadcasting her regular quarter-hourly report to a large ''drive-time" listening audience on WNBC: "Heading to New Jersey, the outbound Lincoln Tunnel looks a lot better for you. In New Jersey . . ." she said. Then she gasped and screamed: "Hit the water! Hit the water! Hit the water!"
After a long pause, a stunned Joey Reynolds, the disc jockey, said: "OK, we're gonna play some, uh, some music here, I think. Find out what's going on with the helicopter. There's something happening . . ."
The cause of the accident was not immediately known.
On April 18 Dornacker was aboard a WNBC traffic helicopter that crashed. She and the pilot escaped unharmed.
Reynolds said that after the first crash, Dornacker "was getting afraid of flying," and had worked from the studio for a time. Recently, he said, she had been getting "a little more confidence back."
Spectrum Helicopters owned the craft involved in both accidents, said Doug O'Brien, the news director of WNBC. In 1985, the company was grounded for safety violations by the Federal Aviation Administration.
Dornacker had worked for WNBC radio for about a year.
She had a small acting role as the humorless Nurse March in the movie, ''The Right Stuff." In 1968, according to Lori Guidice, a WNBC advertising and promotion coordinator, she gained attention as the nation's first female mail carrier.
Between 1976 and 1980, she worked as a dancer and comedian, and performed with the satirical rock group The Tubes. Guidice said Dornacker won the Golden Cabaret Award three years in a row as the outstanding female comedian in San Francisco.
Between 1981 and 1984, she was the morning traffic reporter on San Francisco radio station KFRC. In November 1985 she went to work for WNBC.