Special to World-Telegram and Sun

MITCHEL FIELD, L. I., Sept. 11--Two Air Force pilots reported today their futile chase at 450 miles per hour, of a strange round object that roared across the New Jersey coastline at better than 900 miles an hour. 

For fleeting minutes their T-33 jet trainer got on the tail of the weird object--or about 8,000 feet away--but soon lost it at sea off Sandy Hook, N. J. 

The pilots told officers here it was not a weather balloon.  The Air Force had previously stated that "flying saucers' had been nothing more than weather balloons.  Report of the chase was made by Lt. Wilbert Rogers and Capt. Edward Ballard Jr. on a routine flight. 

"This couldn't have been a balloon," said Lt. Rogers, "It was descending and no balloon goes that fast." 

The flying object--which Lt. Rogers said looked like a small fighter plane--moved in a wide arc from Sandy Hook, N. J., to Red Bank, N. J.  He estimated its speed at 900 miles an hour because it covered the 30-mile course in two minutes. 

The jet trainer opened up wide and followed the object, getting as close as 8000 feet, according to Capt. Ballard. 

The object did not seem to be fleeing from its pursuers, as its speed appeared constand, the pilots noted. 

Lt. Rogers told his superior officers: 

"I don't know if it was a flying saucer, but it was sure something I've never seen before.  We couldn't have caught it with an F-86."  (The F-86 Sabre Jet is the United States' fastest jet fighter plane.) 

The pilots agree that it was white or silver-colored and about the size of a fighter plane.