The Air Force has revised upward by $82 million its cost estimate for constructing a West Coast launch pad for the reusable space shuttle.

The Air Force blamed inflation for the latest cost increase, saying through a spokesman that contractors bidding on the second phase of the launch pad construction contract all came in with bids at least $24 million over the Air Force estimate of $79.6 million.

On analyzing the bids for the second of four construction phases, the Air Force concluded that it will cost at least $200 million to complete construction of the shuttle launch pad, compared with the $118 million it estimated less than three years ago.

So tight is the construction schedule that the Air Force plans to ask Congress for authority to move money out of other military construction projects into the launch pad project to stick to its timetable, which calls for the first shuttle launch from the West Coast early in 1984.

The Air Force has completed the first phase of its shuttle pad construction, which was excavation of the land at Vandenberg Air Force Base in northern California, where the pad will be built. That cost $4.8 million. i

When the Air Force opened the bids not long ago for the second phase, it found the lowest bid was $103.9 million. Four others ranged from $109 million to $112 million, instead of the $79.6 million the Air Force estimated.

The second phase involves construction of the ground level concrete, a payload preparation room, the launch mount on which the shuttle will sit, and nearby storage tanks for liquid rocket fuels and supercold helium to force the fuels into the shuttle. Many miles of electrical cable will also be laid during the second phase of construction.

The single most significant factor cited by the five bidders for their prices was inflation, especially the price of assembled electrical equipment and copper cable. Steel, concrete and labor costs were also said to be higher.

Air Force spokesmen said the launch construction schedule is so critical it will have to ask Congress for permission to "reprogram" its construction budget to stay on schedule. This will involve funds out of other construction projects into shuttle launch pad construction.

The shuttle will be launched first from Cape Canaveral in Florida, then from Vandenberg, to carry civilian and military satellites into polar orbit, where they circle the globe. Satellites cannot be launched from Florida on trajectories that will carry them into polar orbit because they could fall on land in case of a mishap right after launch.

The space shuttle has been plagued by cost overruns, inflation and delays ever since it was approved by President Nixon in 1971. Estimated to cost $5.1 billion in 1971, the shuttle's projected cost through its first four test flights is now $8.9 billion. Supplemental budget requests of $185 million and $300 million were made to keep the shuttle on schedule, the second of which was approved recently by a 10-to-9 vote in the Senate Budget Committee.