The Air Force yesterday launched a Titan 3C rocket with a classified satellite cargo in a mission surrounded by unusually tight security.

The rocket, with 24 million pounds of thrust lifted the craft from the launch pad, and, after two minutes, its booster engine jettisoned from the main vehicle, a pattern normal in nonclassified Titan flights.

A terse Air Force statement said only that an Air Force and industry team participated, but didn't say whether the launch had been successful.

Observers said hte protective ring of security - with guard dogs and Air Force combat personnel supplementing the complex's usual guard force - was heavier than for any previous launch at the Cape.

Even the workers at the launch pad weren't told the type of playload aboard the Titan 3C and were given passes only for the specific areas of their assigned duties.

The Titan 3C, second only in power to the Saturn V which lifted Apollo astronauts toward the moon can lift up to 10 tons into space. It has been used several times to launch military intelligence satellites, and also is capable of lifting a series of satellites, and also is capable of lifting a series of satellites and droppin geach in various orbits.

The previous classified launch from the Cape occurred on April 6. making this the shortest interval between classified missions in the more than 11 years.