The Army intends next year to form some combat units in a new way it hopes will help fire up the troops.

Soldiers and officers, under the plan just approved in principle by Gen. E. C. Meyer, Army chief of staff, will be kept in the same unit during their first tour rather than being transferred from one outfit to another, as they often are now.

"This is a rather profound change for the Army," Lt. Gen. Robert G. Yerks, Army personnel chief, said in an interview. He said Meyer signed off on the experiment Friday, with the proviso that some lingering questions be answered before it is carried out.

Now, a soldier reporting for duty after basic training is regarded and is treated as the new man in the barracks. He is transferred repeatedly during his first tour under today's individual replacement system. Critics contend this keeps him from feeling and acting as a prideful member of a team.

Under the experiment scheduled to start with up to 20 combat companies this spring, a teen-ager would sign up for a specific Army division at the recruiting station. He would become a member of a company of 185 men for that division at basic training, even to wearing the outfit's patch.

After completing six of his eight weeks of basic training, the new soldier would come under the officers and sergeants who would command him for the next three years.

Those officers and sergeants would be from an operational base. The new soldier's officers and sergeants would finish the basic training, then take him and the rest of the new company back to their base for advanced training.

The company would remain there for 18 months and then serve together overseas for the next 18 months. The soldiers on this first foreign assignment would not have wives or children with them, in order to ease housing shortages.

Most of the first-term soldiers would leave the Army after that, having completed their three-year obligation in the combat branches. Their officers and sergeants would return to the operational base to train another company, staying stateside at least 18 months, with their families settled near the home Army base.

The assurance of returning home for at least 18 months is seen by Army leaders as a way to stem today's exodus of the people needed most: The experienced sergeants and officers.

"It's my job as personnel chief," Yerks said, "to solve this short turnaround in the States, which in turn causes soldiers not to reenlist. It's a married Army. This young wife, with two children, of a noncommissioned officer finds herself with a husband who is moved overseas every nine months. She goes through this about twice and then says, 'Uh, uh.No more. We're going to get out and do something where I can raise a family rather than just running back and forth to Europe.' That's a basic problem."

Every time a sergeant quits for that reason, there are fewer to spread around in units stationed here and overseas. This, in turn, means the remaining sergeants must be rotated overseas more often, aggravating the problem of not having enough time to put down roots. Almost half of today's Army, 43 percent, is stationed overseas in what some Army leaders compare to the deployment pattern of the Caesars' Roman armies.

The Army will experiment in 1981 with assigning sergeants to a regiment in a division "for a long period of time," Yerks said. "Then if his son is in high school in the States, or some other similar situation, and he doesn't want to go on that trip to Europe, the sergeant can go over unaccompanied for that 18 months while his family stays near Fort Riley [Kan., for example] where they have the house and stability."

Yerks said a typical Army company loses half its 185 people every year because of transfers and attrition. This means, the general added, that the sergeants and officers -- even in the unlikely event they stay with the company -- do not get the chance to put together a cohesive, well-trained unit with the pride and spirit that can make the difference between winning and losing on the battlefield.

"Developing cohesive units over time," Army chief Meyer said in his "white paper" on how the Army should prepare for the 1980s, "must be the central focus" of Army manpower efforts.

Critics predict this experiment will be a disruptive undertaking that will be pronounced a success but will not solve the Army's basic problem. That problem, critics contend, is that too many units do not have leaders good enough to instill in the soldier a sense of individual pride or respect for his outfit.