President Obama's call for government workers to cut back on driving and travel to reduce air pollution has angered business travel leaders who say he is once again hurting the travel industry.

Mr. Obama issued a directive in July ordering government workers to commute and travel less to reduce greenhouse emissions 13 percent by 2020. That, he said, would eliminate 101 million metric tons of carbon dioxide.

But the National Business Travel Association, a trade group for business travel managers, called the plan a "misguided swing at the travel industry" that could "undermine the slight recovery the travel industry is just now starting to experience."

The association and other travel industry leaders bashed Mr. Obama in February 2009 when he spoke out against corporate executives who spent on lavish travel after accepting government bailout money.

"You can't get corporate jets, you can't go take a trip to Las Vegas or go down to the Super Bowl on the taxpayers' dime," Mr. Obama said last year.

The industry leaders said the comment hurt business travel at a time when the sluggish economy was already taking a devastating toll.

The National Parks Service celebrates another fee-free weekend, Aug. 14-15, when more than 100 of the national parks will offer free admission. That's a value of $3 to $25 depending on which park you visit.

The free entry covers all the major parks -- Yellowstone, Yosemite, The Grand Canyon, Cape Cod National Seashore, Everglades National Park -- as well as myriad others around the country. Find a national park at www.nps.gov/findapark. Parks in Western Pennsylvania include Fort Necessity National Battlefield, Flight 93 National Memorial, Allegheny Portage Railroad National Historical Site, Johnstown Flood National Memorial, Friendship Hill National Historic Site.

Other fee-free days this year: Sept. 25 (Public Lands Day) and Nov. 11 (Veteran's Day).

The U.S. Department of Transportation's new fines against airlines that leave passengers stranded on the tarmac have been in place about three months, and already the fines have sparked intense debate.

Under the rules that took effect April 29, the agency can levy fines of up to $27,500 per passenger on a plane delayed three hours or more. Airlines can avoid the fines by unloading passengers before the three hours pass.

The agency has yet to levy any fines. But a new study by two aviation consultants concluded that the rules will cause airlines to cancel up to 5,200 flights a year to avoid the fines, leaving about 400,000 passengers to scramble to find substitute flights.

In short, the report by analysts Joshua Marks and Darryl Jenkins says the hassles for passengers far outweigh the benefits intended by the new rules.

"We conclude," the report said, "that DOT's tarmac rules and punitive fine threats have driven significant cancellations and public costs far in excess of quantifiable benefits."

The department rejected the report's findings, saying it was based on one month of airline data, making it too narrow to reach a "defensible conclusion."

In a statement, Transportation Secretary Ray LaHood, said, "no one should be misled by this unreliable study."

With full-body scanners going into airports around the country, a Las Vegas firm is selling shields designed to protect your, er, intimate areas from scrutiny.

They cost $10 for men and $17 for women (who get three of the 2-millimeter-thick rubber panels). But a spokesman for Flyingpasties.com conceded that the shields have not been tested under an airport scanner to see if they can block the X-rays or radio waves.

What's more, a Transportation Security Administration official pointed out that if a scanner detects any object underneath a passenger's clothing that is not skin, that passenger will be pulled aside for a full-body pat-down search.

Sounds like the modest should just opt for the pat-down.

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