Rep. John Mica, chairman of the House Transportation and Infrastructure Committee, said there had been a "lack of leadership" and he decried what he said was a stalemate as FAA failed to put in place some aspects of the new technology.
"It is not acceptable, period," said Mica, R-Fla.
Lawmakers also questioned how the program will stomach across-the-board budget cuts that will go into effect on Jan. 2, barring congressional action. Porcari said the effects would be drastic and would slow down NextGen, but he pledged that safety would be protected.
He said a report to Congress this week would lay out specific impacts of the cuts.
A political squabble involving the FAA's leadership also has hamstrung the overhaul.
The FAA hasn't had a full-fledged administrator since December, when Administrator Randy Babbitt resigned after a drunken driving arrest. President Barack Obama nominated Huerta, who had been in charge of NextGen, to replace him. But Huerta's nomination has been held up in the Senate. Although Huerta is running the FAA in an acting capacity, his old job can't be filled until he's confirmed.
"He has two day jobs right now," Porcari said.
Huerta chimed in later: "I would love to have a deputy."
Industry groups, including the air traffic controllers group, the National Business Aviation Association and the Port Authority of New York and New Jersey, told the subcommittee that they believe in the program and its importance for the future of U.S. air travel.
The CEO of low-cost air carrier JetBlue Airways, Dave Barger, said new GPS technology is being installed on 35 of his airline's jets and will be completed by the end of the year.
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