Roche Diagnostics Corp. is ramping up cargo shipments between the U.S. and Europe, securing a third weekly Cargolux flight at Indianapolis International Airport to ship its medical products overseas.

The flight, to begin on Sunday, will be the first scheduled Cargolux flight to depart Indianapolis and fly nonstop to Europe – opening up new export capabilities from central Indiana.

Currently, Cargolux Airlines International operates two inbound flights from Luxembourg to Indianapolis, each Wednesday and Friday

Boeing 747 freighters – an uncommon sight at Indianapolis  – typically take on Roche’s chemical reagents and medical devices then stop in Chicago or other cities before heading back to Europe.

The new flight will help Roche better synchronize its supply chain, said Thurman Walker, general manager of DB Schenker’s Indianapolis logistics center, which handles Roche’s shipments at the airport.

The goods will be loaded at the airport when Roche’s local operations are closed. But they will arrive in Europe for timelier processing. That could speed deliveries to customers there by two days, said Jim Lafayette, director of distribution operations for Roche.

The outbound Boeing 747 will have room for additional cargo. “Hopefully our volume will keep growing,” said Eric Martin, head of North American supply chain at Roche.

That extra aircraft capacity also could accommodate goods of other companies wanting to ship to Europe.

The third Cargolux flight is a boon for the Indianapolis Airport Authority, which for years has been touting the airport as an alternative to bigger and more congested airports such as delay-prone Chicago O’Hare.

Indianapolis International is the nation’s eighth largest cargo airport, although most of the cargo moves via a single company – FedEx.  The Memphis carrier operates its second-largest domestic cargo hubin Indianapolis.

Further diversification--Cargolux’s new flight-- helps underscore that “Indianapolis is a legitimate player” in cargo, said Christofer Matney, air service director for the airport authority.

Matney travels the world pitching Indianapolis’ cargo potential, which has grown since the airport opened a new midfield passenger terminal almost four years ago. The site of the abandoned former passenger terminal is ripe for cargo operations, with direct access to the airfield.

There’s more than 2 million square feet of such airfield access on the northeast corner of the airport alone for wide-body freight aircraft. That’s an amount roughly equivalent to what O’Hare has today.

Indianapolis has seen a number of new international cargo flights over the last couple years. In November, FedEx won federal approval to launch an air cargo route between Indianapolis and Guadalajara, Mexico.

FedEx, which employs about 4,000 people at its Indianapolis hub, also has been making regularly scheduled flights from Indianapolis to Paris-Charles de Gaulle Airport.

Two years ago, FedEx began nonstop service from Hong Kong to Indianapolis.

Cargo is big business for Indianapolis International, a medium-sized airport that is more a spoke than a hub for passenger service and thus has struggled to land nonstop passenger flights to Europe.

FedEx alone pays more in landing fees than all 10 passenger carriers here – about $10.4 million annually vs. $10 million for the passenger airlines.

In the first nine months of 2011, FedEx shipped 1.45 billion pounds of cargo at Indianapolis International, or 724,619 tons.

Cargolux began the first nonstop air cargo service here from Europe in 2006, quickly adding a second flight to serve Roche and Schenker.

“Six years ago, these guys took a very bold step,” said Matney, who hopes to continue to attract additional cargo flights.