US airlines and a broad swath of industry groups are calling on President Donald Trump and lawmakers to end a partial government shutdown that has delayed aircraft certifications and left aviation workers unpaid.

The calls come as the effects of the shutdown, soon to enter a third week, continue rippling through the aviation industry.

Though US commercial airlines have operated with minimal disruption, the Federal Aviation Administration's partial closure has forced Silver Airways to delay entry-into-service of its first ATR turboprop.

The shutdown has also raised questions about Delta Air Lines' ability to place its first Airbus A220 into service as planned on 31 January.

"Certification and regulatory reform activities have halted and validation activities between FAA and other aviation authorities cannot be completed," says a 10 January letter from 30 aerospace groups to President Trump, House Speaker Nancy Pelosi and Senate Majority Leader Mitch McConnell.

"Airlines and charter operators are not able to add new planes to their fleets due to a lack of authorisation through the FAA," the letter says. "We urge you to act quickly to resolve these issues."

The letter's signees included the Aerospace Industries Association, Air Line Pilots Association, Airlines for America, IATA and groups representing air traffic controllers, MRO shops, private pilots and airports.

The partial shutdown began 22 December after Trump and lawmakers failed to agree to a government spending bill. The sticking point has been Trump's insistence for, and democrats' resistance to, funding for construction of a barrier along the US-Mexico border.

Though air traffic control towers remain open, the shutdown has "curtailed" FAA work related to aircraft certification, airworthiness directives, airspace modernisation and pilot and mechanic licenses, says the letter.

"Aircraft that have been delivered to airlines are idled until the FAA authorises their operation," it says.

Affected carriers include Silver Airways, which says the closure has further delayed the launch of its first ATR turboprop flights.

"Silver is in the final phase of receiving regulatory approval to operate the first of our new ATR," Silver tells FlightGlobal. "While we understand that regulators are limited in what they can do during the government shutdown, we are exceedingly frustrated and disappointed that the shutdown is causing a delay in launching our new planes."

Delta declines to discuss the certification status of its new A220s, which the carrier has planned to place into service on 31 January. Delta "continues to monitor the situation" and does not anticipate any schedule or customer disruption, it says.

Also on 10 January, the National Air Traffic Controllers Association led an rally outside the US Capitol.

"End the shutdown today," NATCA president Paul Rinaldi told a crowd. He called government employees "political pawns" in the budget battle, noting that controllers have been working without pay.

Source: Cirium Dashboard