Money talks in post-communist Poland, and nowhere is that more obvious than at the Polish Air Force Academy.

Beginning Monday, the academy, once a bastion of secrecy, will open its doors to anyone who wants to shell out big bucks to go aloft in antiquated military aircraft.Five foreigners - four from Britain and one from the Netherlands - are tentatively signed up for the inaugural week of "flying holidays," which, if successful, will be offered for as many as 30 people every other week through next fall. The program is being advertised in aviation industry magazines in Europe and through travel agents in the United States.

"Our goal isn't really to make money. It is to host people who love flying," says Jerzy Dembowski, managing director of Cenrex, the state-run trading company that organizes the flying holidays.

Nonetheless, people who love flying will pay dearly for the privilege of being a guest. Besides paying their own way to Poland and $468 a week for food, lodging and other basic costs, visitors will be charged as much as $2,000 for each hour of flying time.

"The costs depend on the kind of aircraft you want to fly," says Col. Wlodzimierz Gajda, an air force instructor who manages the holiday tours. "We have everything from balloons to supersonic jets. We have helicopters, sport planes, propeller planes - even transport planes."

The biggest bargain going is a jaunt in a hot air balloon, which costs a mere $186 an hour for two. An ancient An-2 biplane goes for $320 an hour, and an Mi-2 helicopter can be had for $425 an hour.

Jet enthusiasts can fly the two-seater Iskra TS-11 trainer for $660 an hour or open their wallets wider and move up to the Soviet-built MiG fighters that once formed the front line of Eastern Europe's air defenses.

A little more than $1,000 buys an hour in a MiG-15 jet trainer, while $2,000 buys an hour in the cockpit of a MiG-21 supersonic fighter.

By military standards, all the aircraft being offered to tourists are obsolete. The MiG-15 and TS-11 date back to the late 1940s and early 1950s. The Mi-2 helicopter first flew in 1961. And the MiG-21 long since has been replaced, even in the Polish Air Force, by four new generations of jet fighters.

Even so, the sheer novelty of being able to fly once-forbidden aircraft is attracting foreign tourists to Poland.

"There are a lot of delegations from abroad that are really interested," says Col. Gajda. "We are open for business."

Gajda says two members of the inaugural group already have signed up to pilot MiG-21s. Another has requested the MiG-15. The rest plan to fly the Iskra TS-11.

All five members of the first group, and most of the more than 80 foreigners who already have expressed interest in the tours this summer, are veteran pilots. Even so, they must undergo a week of medical examinations, ground training and in-flight instruction before they are allowed to take the controls.

"We may have people who know very well even an F-14 fighter, but they may never before have sat in one of our planes," says Dembowski. "They must begin as passengers.

"After 15 or 20 minutes of flight you know whether this is an old pilot or whether this is just a passenger who needs a new experience - a new thrill."