You might call it an invasion of choppers and shoppers.

For three days, starting on Thursday, Helicopter Association International will bring the world’s largest civilian helicopter trade show to the Miami Beach Convention Center.

For helicopter buffs, the show will be a smorgasbord of rotor blades and turbine engines. More than 70 whirlybirds of every shape and size will be on display. There also will be nearly 400 exhibits, from helicopter airframes to accessories.

For South Florida’s tourism and business community, the show means money, perhaps as much as $20 million flowing to local hotels, restaurants and shops. About 11,000 trade show participants have booked nearly 3,000 hotel rooms.

“It is really the most important and the largest professional helicopter trade show,” said Frank L. Jensen Jr., president of Helicopter Association International. “It’s the one time of the year, wherever you fit into the helicopter industry, this is the place you kind of have to be.”

The show also is an opportunity for exhibitors to make money. One helicopter manufacturer sold $200 million worth of orders at the association’s 1989 show, Jensen said.

Helicopter Association International is a professional trade group representing more than 1,100 firms in 51 countries. Its members operate 4,000 helicopters, which fly more than 2 million hours each year.

This year’s show, the association’s 45th, is the first in South Florida since the early 1960s.

As part of the trade show activities, the association will present its Pilot of the Year award to Maurice Johnson, who flies WSVN Channel 7’s news helicopter.

Johnson, who has been flying choppers for 40 years, won for his work following Hurricane Andrew. He provided the television station with the first air-video of storm damage. He also transported military personnel.

Don Mitchell, president of the Helicopter Association of Florida and a Metro-Dade Air Rescue pilot, will accept a humanitarian service award on behalf of helicopter pilots who had a hand in relief efforts.

TRADE SHOW FACTS

About the Helicopter Association International show:

— WHERE: Miami Beach Convention Center, on Washington Avenue between 17th and 20th streets. Also is an entrance on the west side of the building, on Convention Center Drive. Take I-95 to I-195 to Miami Beach.

— ADMISSION: $50 per day.

— ON SUNDAY: Public awareness day at Watson Island on MacArthur Causeway, after trade show, from 10 a.m. to 3 p.m. Helicopters will be on display, with rides available. Free admission. Take I-95 to I-395.