WASHINGTON (Reuters) - Stepped-up security screening at airports in the wake of foiled terrorism plots has provoked an outcry from airline pilots and travelers, including parents of children who say they are too intrusive.

With the busiest holiday travel season nearing, fliers face long security lines and new rigorous patdown checks begun in recent weeks aimed at discovering hidden explosives. As a result, some travelers are questioning whether to fly at all.

The Transportation Security Administration has ramped up airport security after two plots by al Qaeda in the Arabian Peninsula. A Nigerian man hid a bomb in his underwear last Christmas and the group tried to send package bombs via U.S. cargo carriers but none of the explosives detonated.

To thwart such attacks, TSA is deploying body scanning machines to U.S. airports but travelers and pilots have complained about potential health risks and that they are too intrusive. The alternative is a physical patdown by a TSA officer.

“Pilots are not the terrorist threat,” said John Prater, president of the Air Line Pilots Association and a veteran pilot for United Continental. “Seeing scarce security resources being used on pilots makes absolutely no sense.”

Some pilots, male and female, have complained the patdowns make them feel uncomfortable. The group urged any pilot who feels unfit for duty afterward to “call in sick and remove themselves from the trip.”

That has prompted urgent talks between the pilots’ group and TSA Administrator John Pistole. The two sides hope to resolve the matter in a few weeks, Prater said.

‘GATEWAY TO COMMERCE’

Executives from the travel industry, including online travel sites, theme parks and hotels, were set to meet Homeland Security Secretary Janet Napolitano and Pistole on Friday to discuss their concerns that security is crimping travel.

“We have received hundreds of e-mails and phone calls from travelers vowing to stop flying,” said Geoff Freeman, an executive vice president of the U.S. Travel Association, which set up the meeting with the Obama administration officials.

“You can’t talk on the one hand about creating jobs in this country and getting this economy back on track and on the other hand discourage millions of Americans from flying, which is the gateway to commerce,” he said.

Privacy groups have challenged the new body scanners in court, saying they are a violation of privacy and illegal. Lawmakers plan to hold hearings on aviation security next week when they return to Washington.

Some travelers are also livid about how children are being screened. During a trip last Sunday by a father and son through Orlando airport in Florida, the 8-year-old boy was selected for extra screening by TSA after going through the metal detector.

The father said the officer described the procedure before conducting it. Then he patted down the boy in the open security area, using the backside of his hands to check his genital area, he said.

“I didn’t think it was going to be as horrible as he was describing,” said the boy’s father, Bill, who works as a lobbyist in Washington and did not want his full name used.

“We spend my child’s whole life telling him that only mom, dad and a doctor can touch you in your private area, and now we have to add TSA agent and that’s just wrong,” he told Reuters. “At some point the terrorists have won.”

TSA defends the body scanners as safe and says the devices and friskings are key tools to help detect hidden explosives.

“While for security reasons we can’t get into the specifics about our security procedures, our officers are trained to work with parents to ensure a respectful process for families and we are reviewing our policies for children,” the agency said.