Washington will get its first glimpse of the freed American hostages Tuesday afternoon, when a motorcade of two buses and assorted limousines will carry the returnees and the VIP's scheduled to welcome them from Andrews Airport to the White House for a presidential reception.

With military bands and color guards representing all four branches of the service in the background, the returnees and 150 of their family members -- who are to be reunited at West Point this afternoon -- will be met by Vice President and Mrs. Bush, Secretary of State and Mrs. Haig, Secretary of Defense and Mrs. Weinberger, assorted congressional leaders and other family members on the tarmac at Andrews at about 12:30 p.m.

At 1:15, the motorcade will "move slowly" toward the White House, heading out Suitland Parkway, over the South Capitol Street Bridge to Canal Street, down Independence Avenue to 3rd Street, and finally to Pennsylvania Avenue, where they will follow the inaugural parade route around the Treasury Building to the North Portico of the White House.

Though a state department spokesman said he expects thousands to turn out along the route to welcome the returnees, he said that officials believed that the idea of a full-blown parade was vetoed because "our principal concern is for the health and well being of the individuals . . . some may not yet be up to such a strenuous schedule."

The returnees, who the spokesman said "are considered heroes in the eyes of this [State Department] building, this administration and the American people," will then gather on the South Lawn for a short address by President Reagan.

Following that, they will reassemble for a "full-fledged" diplomatic reception in the East Room. Joining them at the 3:30 reception will be members of the cabinet, the joint chiefs of staff and ambassadors from several countries -- Great Britain, Algeria, Switzerland, Canada and Germany -- that played a role in their return. The spokesman also acknowledged that several other countries, who participated but wish to remain anonymous, will not be attending.

Shortly before 5, President Reagan will make a farewell address and then the returnees and their families will be bused from the North Portico to their hotel, believed but not confirmed to be the Crystal City Marriott. On Wednesday, after spending the night at the hotel, they will be flown to their home towns.