By Andrea Shalal

COATESVILLE, Pa., Oct 16 (Reuters) - The embattled U.S. Export-Import Bank on Thursday said it had authorized $1.7 billion in financing to support U.S. exports of helicopters, business jets and agricultural aircraft since fiscal 2012, aiding a sector that was hit hard by the 2008 financial crisis.

Fred Hochberg, president and chairman of the Ex-Im Bank, said the financing had helped companies such as Sikorsky Aircraft, a unit of United Technologies Corp, pump up their exports by giving their customers access to the same kind of export credit financing offered by their competitors.

"We want to make sure that when Sikorsky is competing with Airbus, that it's a level playing field. People need to know that financing is available," he told Reuters during a visit to a sprawling Sikorsky plant in rural Pennsylvania on Thursday.

The bank has come under attack from some Republicans, who view it as an example of big business welfare and want it wound down. Supporters say it plays a vital role in driving exports.

Hochberg, who visited the Toulouse facility of the European aerospace giant Airbus last week, said the bank's financing for general aviation deals would reach $2 billion by the end of the year, doubling a target set in February 2013.

Aerospace is the bank's largest export category after agriculture, he said.

Hochberg's visit to the plant where Sikorsky builds S-92 and S-76 commercial helicopters is part of a big push to show how the bank's export credit financing and insurance are helping create and protect jobs in across the United States.

The bank, which provides loans to foreign buyers of U.S. goods and other support to U.S. exporters, last month won a nine-month extension of its charter through June 2015 but is continuing to press Congress to grant a long-term extension.

Supporters say closing it would be a blow to Boeing Co , Caterpillar Inc, General Electric Co and others that rely on Ex-Im financing to make sales and compete with foreign firms.

Dorith Hakim, general manager of the Sikorsky Coatesville facility located about an hour west of Philadelphia, said the workforce had grown from 700 to around 1,800 over the past three years as the company expanded to meet strong commercial demand.

Exports had risen to comprise about 50 percent of production at the plant, up from about 20 percent five years ago, she said.

Hakim told Reuters the availability of export financing was a big factor in Sikorsky's ability to close commercial deals.

"The commercial helicopter market is extremely competitive," she said. "It's important that our customer have the feeling of security of a financing arm for them to actually make the purchase decision."

Hochberg said he visited Airbus last week after a regular meeting with G7 officials to take a firsthand look at the main competition for many U.S. manufacturers.

Airbus spokesman Clay McConnell confirmed the visit and said the two sides had a cordial exchange of information.

(Reporting by Andrea Shalal; Editing by Cynthia Osterman)