As the Sept. 30 deadline to renew Federal Aviation Administration programs approaches, members of both parties are working to reach a deal on a consensus bill that could be acceptable to both chambers.

The process has been slowed because the Senate did not pass its committee-approved bill. Negotiators in an informal conference committee don’t know how many of up to 90 amendments offered to the Senate measure could be in play or whether any senator will object to a final bill that doesn’t include his or her priorities.

Still, the staffs of the committee leaders have been meeting for two weeks to try and reach a consensus. Each of the members involved comes with individual priorities.

Rep. Bill Shuster, R-Pa.

Nearing the end of his last term in Congress and third as House Transportation and Infrastructure chairman, Shuster considers the FAA measure “urgent.”

After steering a surface transportation law to enactment in 2015 and reviving the two-year cycle for water resources development bills in 2014, 2016and 2018, the Pennsylvania Republican sees a long-term FAA bill as the last major policy area that’s eluded him as chairman.

“This will be the final bill that I’ve been able to do a longer term,” Shuster said Friday. “It’s urgent.”

For years, Shuster pushed long-term authorization bills that included a proposal to spin off the air traffic control system to a private nonprofit entity. After conceding earlier this year that not enough House members could be persuaded, Shuster dropped the issue and introduced a bipartisan bill.

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Rep. Peter A. DeFazio, D-Ore.

The ranking Democrat on House Transportation and Infrastructure has several priorities he’s pushed for years, including changing the certification procedure of aircraft and parts, and updating drone regulations. Despite working with Shuster on those items in 2015, the Oregon lawmaker opposed bills because they included the chairman’s spinoff plan.

With a bipartisan bill and time running out, he feels now is the time to finally get a long-term extension.

“We needed certification reform three years ago,” he said last week. “We wasted three years on privatization of the FAA. It’s time to get the damn bill done.”

Sen. John Thune, R-S.D.

The Senate Commerce, Science and Transportation chairman wrote the Senate version of the bill and made a concession to smooth passage by agreeing earlier this year to drop an amendment that would make it easier for pilots-in-training to earn their license.

But the South Dakota Republican’s efforts have yet to achieve passage because other issues, including an amendment on truckers’ hours of service, are preventing consensus. Thune has often said he hoped for floor action shortly on a bill that the committee approved in June 2017. But without an agreement on the substance, other senators have not let it reach the floor.

Shuster singled out Thune and Senate Commerce ranking Democrat Bill Nelson of Florida as sharing his urgency to pass a bill, adding he couldn’t say the same for every senator. But while Shuster has refused to entertain the idea of another extension, Thune has also acknowledged one could be needed, saying if a deal isn’t reached by Sept. 30, the end of the calendar year could be acceptable.

“I certainly don’t have any intention of doing a long-term extension,” Thune said. “I hope we can get it done by the end of the fiscal year, but if we can’t do that then the goal would be to resolve these differences by the end of the calendar year.”

Reps. Frank A. LoBiondo, R-N.J., and Rick Larsen, D-Wash.

The leaders of the House Transportation Aviation Subcommittee each have a district-specific interest to represent.

For Chairman LoBiondo, that’s the William J. Hughes Technical Center, an FAA air transportation system laboratory in the Republican’s southern New Jersey district. LoBiondo, who’s retiring at the end of this term, has for years pushed for a long-term extension like the House’s six-year authorization, only to see extensions carry the day.

The workforce at that facility and throughout the FAA is highly educated and skilled, he said last week. Every time an authorization deadline approaches, they have to stop their work to prepare for a shutdown. The interruption costs taxpayers, he said.

“Nobody understands how inefficient, how costly and how wasteful it is,” LoBiondo said. “And a waste of real big talent.”

Ranking Democrat Larsen has prioritized overhauling the certification process that’s the top priority of the aerospace manufacturing industry, a giant employer in his home state of Washington. More than 1,500 aerospace suppliers operate in the state, he said, including Boeing. Tweaking regulations to allow speedier safety certification of aircraft and parts is crucial to let those businesses keep up with competitors overseas, he said.

“The ability to get their products and components certified quickly and reliably actually cuts down on their costs and gets products to market sooner,” Larsen said.

Both version of the FAA authorization bill include measures to address the issue, including making it easier for organizations to be designated as “Organization Designation Authority” to provide some oversight functions on the FAA’s behalf.