As summer vacationers visit their destinations and return home, Congress is considering a sweeping tally of proposals that could affect travelers, from dictating seat size and leg room to rolling back rules that require airlines to advertise the full price of a ticket.

The current law authorizing operations of the Federal Aviation Administration expires Sept. 30. Sen. John Thune, R-South Dakota, chairman of the Senate Commerce Committee, is working to bring his panel’s bill for a five-year reauthorization to the Senate floor after a series of delays. The House passed its version of the same bill in April.

Consumer advocates see victories and setbacks among the provisions in the two bills:

• Airline seats: The House bill would give the FAA a year to set minimums for seat width and length and the distance between rows, although it didn’t set specific measurements. The version approved by a Senate committee would only direct FAA to study whether there should be minimum requirements for the distance between rows.

The room between rows – measured from a point on one seat to the same point on the seat in the next row – has been shrinking for many years as airlines squeeze more seats onto their planes. It was once commonly 34 or 35 inches, and is now under 30 inches on some planes.

Some safety advocates say the tighter fit makes it harder for passengers to evacuate in an emergency. The FAA has declined a consumer group’s request to impose regulations, putting the issue in Congress’ hands.

• Advertised prices: Consumer groups scored a hard-fought victory in 2012 when the Obama administration required airlines to include government taxes and fees in the advertised price of a ticket. Airlines opposed the rule then, and they lobbied the House to include a provision in its FAA bill that would roll back the requirement.

“Consumers need to know the full cost of travel,” said Charles Leocha, president of Travelers United. “Taking a step back to allowing the airlines to advertise airfares without mandatory taxes and fees will be a major step toward allowing deceptive and misleading airfares.”

• Extra fees: The Senate bill would prohibit airlines from charging “unreasonable” ticket-change or cancellation fees. The Transportation Department also would set standards for other fees to make sure they reflect the airline’s actual cost for providing extra service. Airlines raised more than $7.4 billion last year from fees on checked baggage and cancellations.

The restriction was proposed by a pair of Senate Democrats over strong objections by the airline lobby. Sharon Pinkerton, a senior vice president at the trade group Airlines for America, called it a first step toward returning to the pre-1978 era when the federal government set airline prices.

• Overbooked flights. The House would ban airlines from bumping passengers from overbooked flights once they have boarded the plane. The provision was inspired by the 2017 incident in which a passenger was dragged off a United Express plane to make room for a late-arriving airline employee. In response to the criticism, airlines have cut overbooking to their lowest level in at least two decades.

• Online travel agencies. Both the House bill and the Senate’s committee-approved version would require online travel agencies like Expedia and Orbitz to tell consumers about things like extra fees and changes in airline schedules. Vaughn Jennings, a spokesman for the airline trade group Airlines for America, said the online agencies “shouldn’t be exempt from consumer-protection standards that customers experience on airline websites.”

Steve Shur, president of a trade group that includes the online ticket sellers, said airlines don’t always give his companies that kind of information. He called the proposals a veiled effort to drive them out of the air-travel business and reduce competition for the airlines.

• Disruptive passengers. The House bill would let airline employees block passengers from going through security screening or getting on a plane if the employee accuses them of verbal or physical assault. Passengers would be held up until police could sort things out. A union that represents airline employees lobbied for the provision.

There are many other provisions in the bills, including some that are opposed by safety experts. Pilot unions are fighting a trial to test the idea of letting cargo airlines use one pilot instead of two. The unions say that in an emergency, one pilot could be more easily overwhelmed.

An even more controversial idea would reduce the number of hours that someone must fly to become an airline co-pilot. It’s in the bill approved by Thune’s committee but not in the House version.

Congress raised the minimum from 250 hours to 1,500 hours after 50 people died in a 2009 accident near Buffalo, New York. The Regional Airline Association, whose members operate smaller planes flying under the banners of American Eagle, Delta Connection and United Express, say the requirement has created a pilot shortage.

The airline association supports Thune’s proposal to let pilots count time on certain types of training in a classroom or a flight simulator toward the 1,500 hours.

Families of those who died in the 2009 Colgan Air crash have fought that change. They note that after Colgan, there were no fatal accidents involving U.S. airliners until a woman was killed on a Southwest flight in April.

“The (airline association) and others will continue to try any maneuver to water this down. It’s sad,” said Scott Maurer, whose daughter Lorin was on the Colgan plane. “In their eyes it’s not about safety, it’s about their business profits.”

If the Senate acts on the FAA bill, any differences from the House version would need to be settled before a final measure goes to President Trump. If Congress can’t agree, lawmakers could pass a scaled-back, short-term extension to keep the FAA functioning.