CNN  — 

Zachary Annen and his husband arrived at Chicago O’Hare International Airport Sunday night three hours ahead of their flight.

The pair waited more than 2 1/2 hours in the Transportation Security Administration screening line and made it to the gate for their flight home to Seattle with “minutes to spare,” Annen said.

As travelers face hours-long waits at some U.S. airports to clear security, they want to know what’s being done to ease delays:

When will TSA lines get shorter?

Sometime this summer, with any luck.

The Transportation Security Administration is trying to have 768 new security officers in place this summer, as early as mid-June, Department of Homeland Security Secretary Jeh Johnson said last week.

Existing officers are being offered overtime to shorten the lines.

The TSA PreCheck was 45 minutes long on Monday at Atlanta's Hartsfield-Jackson International Airport, one traveler says.

The TSA is also asking the airlines to help with reducing the size and number of passenger carry-on bags and with “nonsecurity” work such as moving bins.

“We are asking the American people to be patient while we bring on the added resources as quickly as possible to alleviate the wait times,” said Johnson, whose agency oversees the TSA, on Friday.

Johnson received permission from Congress to shift $34 million in his budget to increase overtime and part-time hours and to hire the additional screeners.

Why are the lines so long?

The long lines are a far-from-perfect storm.

More people are flying than ever before, yet the TSA’s frontline staffing budget has declined every year since fiscal year 2013.

For fiscal year 2016, the TSA’s authorized staffing level is 42,525 and passenger volume is projected to be 740 million, according to the TSA.

There’s been a 15 percent increase in passenger volume and a 10 percent drop in staffing since fiscal year 2013. Back then, the TSA’s authorized staffing level was 47,147 and checkpoint volume was 643 million passengers.

The agency’s budget represents what the agency can afford, based on the congressionally-approved appropriations, according to the TSA.

Deborah Cross was in the security line for 85 minutes on Monday at Chicago's O'Hare International Airport.

Morale is also a problem at the agency, reports the House Oversight Committee, which is investigating allegations of misconduct.

The union that represents TSA employees says the agency needs to hire an additional 6,000 employees to fully staff security lines.

“Congress has starved TSA of the resources it needs to meet growing demands at our nation’s airports,” said American Federation of Government Employees National President J. David Cox Sr.

How early should I get to the airport?

Traditionally, the TSA advises travelers to get to the airport two hours before your scheduled departure.

Yet three hours might be a better bet, given the summer travel spike and the outcry from airline passengers stranded in long lines.

Packing light and following all the TSA rules around removing shoes, liquids and laptops should also expedite the process when you reach the actual checkpoint.

What else can travelers do?

If you’re a frequent flier, sign up for TSA Pre-Check or Customs and Border Protection’s Global Entry to get expedited screening at the airport.

Pre-Check security lines are shorter and faster, and passengers can keep their jackets and shoes on and computers packed up.

This is what Dave Rogers saw when he arrived at DFW airport at 4:15 a.m. on Monday.

More than 7 million people are enrolled in these “Trusted Traveler” programs – fewer than the agency anticipated.

Travelers can also add their frustrations to the growing number of social posts documenting the problem.

Fliers are posting images and videos of the long lines using the #Ihatethewait hashtag, which was launched by Airlines for America, an airline industry trade group.

What other solutions are in the works?

Faced with long lines, Atlanta Hartsfield-Jackson International Airport – the busiest passenger airport in the world – and other major airports around the country have threatened to replace TSA security with private security companies.

But getting TSA approval for privatized security is not a quick fix.

In the meantime, Atlanta is now scheduled to receive at least 150 of the new TSA officers and additional K-9 units this summer, according to airport spokesman Reese McCranie.

The airport has shut down one of its three security checkpoints to test a new security system – called Innovation Lines – that officials hope will ultimately screen passengers in less time. But for now, that shutdown is adding to the long lines.

Atlanta’s South Checkpoint re-opens on May 24, “and that should greatly improve the wait times,” McCranie told CNN.

CNN’s Michael Pearson, Christina Zdanowicz, David Williams and Thom Patterson contributed to this report.