MOSCOW, JUNE 2 -- The Soviet military, once sacrosanct and immune from public criticism, is now being subjected to the same kind of piercing exposes as the Communist Party and other leading Soviet institutions.

The criticisms spilling out of the pages of Soviet newspapers and letters to the editor columns under the new policy of glasnost -- or "openness" -- go well beyond the recent public humiliation of the Soviet military leadership by a young West German who piloted his Cessna across the Soviet Union and landed in Red Square.

Spurred on, perhaps, by the official Soviet acknowledgment of 19-year-old Mathias Rust's piloting feat and the publicized removal of two top Defense Ministry officials, there were more signs today that the Soviet public was willing to lambaste the military over other matters.

Using the letters column of the Communist Party organ Pravda, for example, a colonel from Leningrad railed against elite, well-equipped military academies spread around the country as playgrounds for the rich and questioned whether the academy's graduates are even prepared for battle.

"Often," the letter said, the cadets are "children and grandchildren from well-off homes -- cosseted, spoiled kids whose families cannot keep them under control. The existing schools, which were set up on the model of the cadets' colleges, have turned into a refuge for parades and for making life easier for certain parents.

"Of course, such schools are necessary," the colonel wrote, "but what if there is a war?"

Although Rust's landing in his small plane at the seat of Soviet power has attracted all the attention, criticism of the military has been rising in recent weeks in the official Soviet media, including exposes of poor discipline, corruption and lagging standards.

In some articles scattered through the state-controlled media, even the eight-year, Soviet-backed war in Afghanistan is viewed with a more critical eye.

In a candid contradiction of the official Soviet line that it was invited into the war, 20-year-old Andrei Novikov said on a Radio Moscow broadcast in March: "As everyone knows, the resistance forces began receiving aid from the West . . . only after the Soviet Union moved its troops into Afghanistan. Which intervention came first and which came second is obvious."

One newspaper dispatch documented the gradual slump of a general -- since stripped of rank and Communist Party membership -- into the depths of hedonism, nepotism and corruption. Gen. Victor Zhigaylo drank freely -- at the Army's expense -- in the face of an official antialcohol drive, according to the article.

"Sycophants, toadies and lickspittles appeared among his entourage," the writer added.

Sergei Sokolov, removed as defense minister last Saturday following the Kremlin landing stunt, said in a published speech last winter that some of the officers were slow to grasp the essence of Soviet leader Mikhail Gorbachev's calls for social and economic reform.

A Pravda article published two weeks ago revealed the lax approach many young Soviets take toward the military. Among recruits, 12 percent fail the physical fitness test, exempting them from the two-year mandatory service.