The summer travel season begins Friday, the first day of Memorial Day weekend, and anxieties abound.

A laptop ban, which has been endlessly discussed and encountered numerous objections, may or may not be imposed at select European airports. A series of cabin incidents, widely viewed on social media, have involved disruptive passengers and made flight attendants wary. And passengers know they may face long airport security lines before boarding crowded airplanes.

Yet, despite all the handwringing, ticket sales are booming.

Airlines for America said a record 234.1 million passengers -- approximately 2.54 million per day -- will fly on U.S. airlines between June 1 and Aug. 31. That is a 4% gain from the summer of 2016.

"The airlines are seeing strong demand and improved yields in 2Q17," Cowen & Co. analyst Helane Becker wrote in a report issued Wednesday. "Most of the airlines have also made positive comments about 3Q17 bookings."

Recently, American (AAL) , Delta and JetBlue all boosted their current quarter unit revenue guidance.

On American's April earnings call, President Robert Isom said, "Looking forward, the revenue environment at American is very strong, and we expect this momentum to continue." Isom said the June quarter will be the sixth quarter in a row when unit revenue improves, the fourth in a row when American outperforms the industry and the third in a row for positive unit revenue.

United (UAL) reported recently that its April passenger load factor gained 260 basis points to 83.1%. The carrier boosted April capacity by 4% and saw 7.4% more revenue passenger miles.

Translation: Airplanes are crowded and becoming more so.

United expects a 2% to 3% second-quarter unit revenue gain. "We see similar trends for the industry and see improving traffic and higher unit revenues driving better earnings per share than is currently in consensus forecasts for the second quarter and full year 2017," CFRA analyst Jim Corridore wrote in a note issued Tuesday.

Airports are also busier.

On Monday, at Charlotte Douglas International Airport, American's second-largest hub, officials projected record local traffic. "We will break records this summer," Jack Christine, deputy aviation director, told reporters.

Starting Thursday, Christine said, the number of locally originating Charlotte passengers will reach 29,000 to 30,000 a day. Within weeks, the number should exceed the record 34,607 reached on April 7. In addition, approximately 100,000 American passengers connect daily in Charlotte.

Across the country, Oakland International Airport said it expects to handle 160,000 passengers during the four-day Memorial Day weekend, an increase of 10% from a year earlier.

Some will fly newly added international flights: Southwest to Puerto Vallarta and Los Cabos, Norwegian to Copenhagen and British Airways to Gatwick. And today, Spirit begins service from Oakland to Baltimore and Detroit.

Despite increased traffic, the Transportation Security Administration said passengers needn't worry about excessively long lines this summer.

Long lines at airports including Chicago O'Hare and Charlotte Douglas made news last spring, but by Memorial Day TSA had taken steps, including boosting screening staff, to cut wait times.

For passengers, the best way is to join PreCheck, which costs $85 for five years. PreCheck resembles a private club, one that excludes potential terrorists. Members get special checkpoints where they can keep their shoes on and their laptops in carry-on bags.

PreCheck has 14 million members, up from 11 million a year ago.

"A lot of people who were standing in line, frustrated, are now in the PreCheck lines," said Charlie Carroll, senior vice president for enrollment services at MorphoTrust USA, which has a contract to process PreCheck applications.

"Even last year, even when everything was going wrong, a person in the TSA PreCheck line stood there for five minutes or less," Carroll said.

In laptop ban news, discussions continue. It may well be that banning laptops is a wise idea based on a realistic threat assessment. However, last week Todd Insler, chairman of the United chapter of the Air Line Pilots Association, told TheStreet, "We all use laptops, but they get very hot.

"It's a bad idea to put them in cargo," Insler said.

U.S. and EU officials are meeting this week to further discuss a ban, Reuters has reported. The EU is not pleased that the U.S. may impose laptop bans affecting some EU airports. Some officials feel that the more the EU engages with the U.S., the longer a decision can be deferred, Reuters reported.

For U.S. airlines, "the real issue would be if the EU announced a reciprocal electronics ban on U.S. passengers to the EU," Becker wrote.

As for the onboard environment, flight attendants await the summer nervously.

"It seems like the respect flight crew members get on flights is deteriorating at a rapid pace," said Bob Ross, president of the Association of Flight Attendants, which represents 26,000 American flight attendants.

In a recent message to members, Sara Nelson, president of the Association of Flight Attendants, which represents about 50,000 flight attendants at 20 airlines, wrote, "The mob mentality response to {recent} video clips, with little correct information about the incidents, has put flight attendants in the cross-hairs."

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.

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