(The Hill) — Off-duty pilots for six airlines are picketing at airports nationwide on Thursday ahead of the busy Labor Day travel weekend in support of improved working conditions and benefits.

The one-day picketing campaign is organized by the Air Line Pilots Association (ALPA), which represents thousands of pilots at major U.S. airlines, and comes at the end of a chaotic summer travel season that has seen a soaring number of passenger complaints as travel demand resurges.

“When ALPA pilots stand shoulder to shoulder in support of shared goals, people notice — our airlines notice,” the union said in a statement. 

“That’s why on September 1, we’re asking all ALPA pilots to join us for an ALPA-wide informational picket to show the public, our lawmakers and our airlines that all airline pilots stand together in support of the profession-wide goal of improved working conditions and benefits,” the statement read.

Pilots are prevented from easily going on strike while on duty under federal regulations, and Thursday’s picketing by off-duty pilots is not expected to affect flight operations.

ALPA organized the picketing at 13 major airports across the country, 11 of which serve as hub airports for major airlines. Pilots for Delta Air Lines, Endeavor Air, JetBlue, Sun Country, Spirit Airlines and United Airlines are participating, the union said.

This comes as airlines have struggled to quickly rebuild their operations to meet the return in travel demand after downsizing during the pandemic. More than 2 million people now travel through the nation’s airports on an average day, the highest level since the start of the pandemic.

The staffing shortages, combined with issues like severe summer storms and high fuel costs, have left passengers frustrated as they face cancellations and delays. 

Passenger complaints soared in the first half of the year, and Transportation Secretary Pete Buttigieg has proposed strengthening federal regulations to clarify when passengers are owed refunds. Buttigieg’s department released a customer service dashboard on Thursday to help passengers understand airlines’ guarantees when they delay or cancel flights.

“@Delta_Pilots are on the picket line at @JFKairport to show @Delta that we’re beyond ready for a new contract,” ALPA’s Delta pilot group tweeted. “It’s been 2.5 years since our contract’s amendable date & 3.5 years since #DeltaPilots last had a pay raise.”

As pilots participating in Thursday’s strike look for increased benefits from their airlines, other ALPA pilot groups have already seen success in negotiating significant pay raises amid airlines’ struggles and a tight labor market.

Pilot unions at three regional carriers wholly owned by American Airlines — Envoy Air, Piedmont Airlines and PSA Airlines — recently announced contract agreements that include significant pay increases. Regional carriers have borne the brunt of what many in the industry view as a national pilot shortage, although ALPA has denied the existence of a shortage.

Many industry workers are complaining about working longer hours and experiencing more last-minute swaps, saying airlines’ recent scheduling snafus will continue without better working conditions.

JetBlue pilots at Los Angeles International Airport on Thursday picketed with signs reading “schedule with integrity matters” and “fatiguing schedules = unreliable operations.”

Some airlines cut back on their August schedules to improve reliability, including Delta Air Lines, which on Wednesday noted the changes as it touted its preparedness for the upcoming Labor Day travel weekend. The airline says it is preparing to serve 2.9 million customers over the weekend.

“We’re looking forward to welcoming our customers on board for Labor Day weekend,” said Allison Ausband, Delta’s chief customer experience officer. “We’ve taken steps this summer to ensure our people have the tools and support they need to deliver on our high standards for reliability, while offering Delta’s signature customer service with warmth and care.”