New pat-down procedures at U.S. airports have been all over the news for the past few months. Pat-downs aren't the only new trends in airline travel. Here are a few other airline developments that have made news, and in some cases, have made waves with the traveling public. (For a related reading, see 7 Air Travel Perks That Used To Be Free.)

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Overbooked Flights
Normal airline practice is to overbook flights to offset no-shows, so even a seat reservation doesn't guarantee you'll board your flight. The airline must attempt to find volunteers for a later flight, usually accompanied by the inducement of a flight voucher or cash rebate. If enough volunteers don't come forward, the airline is required to compensate bumped passengers with $400 to $800 depending on the length of the delay or the value of your ticket, whichever is lower. However, you have the power to negotiate your own deal that exceeds the airline's offer.

While the Department of Transportation is exploring increasing the compensation to as much as $1,300, a seat auction may be a better and more efficient way of attracting volunteers. While some airlines will increase the value of the free voucher if there aren't enough takers, other airlines will not. If the auction approach was implemented across the board, it would produce volunteers at free market rates that aren't constrained by outside forces and would likely keep everyone happy.

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Delayed or Canceled Flights
Schedules aren't guaranteed and airlines aren't responsible for bad weather and air traffic delays beyond their control. Each airline sets its own policies for delays and what form of compensation you might receive. There is no federal requirement for airlines to do anything for passengers who experience delays or cancellations.

If an aircraft is stranded on the airport tarmac while awaiting takeoff or after landing, U.S. domestic flights must return to the terminal within a three-hour limit. This limit can be waived by the pilot if there is a security or safety risk with returning to the gate or if air traffic control can't accommodate the return due to ongoing airport operations. International flights must adhere to their own tarmac waiting guidelines.

After two hours, all flights on U.S. airlines must provide food and water to aircraft passengers while still on the tarmac. Working lavatories must be available and medical attention must be provided whenever necessary.

New Baggage Rules
The current rules on baggage count, weight and size vary widely among the airlines. Most allow at least one carry-on bag and one smaller personal item. Some airlines permit one or two checked bags at no additional cost, while others charge for all bags. International flights may subject you to different weight limits when you have a stopover in a foreign airport.

What you can put in your baggage has undergone evolutionary change ever since September 11, 2001. The heaviest restrictions apply to carry-on baggage and the following items are currently prohibited: Many sporting goods, sharp objects, most tools, guns and firearms, explosive and flammable materials, disabling chemicals, martial arts and self-defense items, and other hazardous items. Nonflammable gels, liquids and aerosols are permitted in containers not exceeding 3.4 ounces (100 milliliters) in a single, clear, quart-size bag. Medications and baby formulas may exceed these limits but must be personally inspected at security checkpoints. (For more, see 4 Reasons Why Airlines Are Always Struggling.)

Security Screenings
Pat-downs at security checkpoints aren't new, but are more intrusive and aggressive than they were in the past. Whereas screeners previously used the back of their hands to brush for hidden objects, they now use fingers and palms to probe and search sensitive and private areas of the body.

The pat-down is used on passengers who refuse to pass through the new advanced imaging technology (AIT) scanners that present a nude image to the screener. They are also used in cases where metal detectors are triggered and detect possible dangerous or prohibited items, or if a person exhibits suspicious behavior. The average operating cost per passenger is approximately $1 per trip through a checkpoint, and a majority of the scanners were funded as part of the economic stimulus bill.

Concerns have surfaced about the potential danger of repeated exposure to the radiation emitted by AIT scanners. The units project low-level X-rays over the body using backscatter technology, and the resulting image is viewed by a TSA official about 50-feet away. According to the TSA, the images are deleted once they are viewed and are not stored or saved. The TSA claims the scans are completely safe and that the exposure is equivalent to the radiation experienced in a two-minute airplane flight at an altitude of 30,000 feet. (For a related reading, see Dead Airlines And What Killed Them.)

In the good old days, you bought your ticket and everything was included. Not anymore. In order to keep ticket prices as low as possible, most airlines are now charging fees for a wide range of a la carte services. The fee for the first checked bag ranges from zero (JetBlue, Southwest) to $25 with several major airlines. For the second checked bag, the fee ranges from zero (Southwest) to $35 for several of the majors.

The airlines are further padding revenues by charging for additional bags, overweight bags, and oversized bags. You might also pay an additional fee for meals, snacks, beverages, pet travel, an unaccompanied minor and preferred seat selection. Some airlines have also upped the mileage requirements for frequent flier redemptions. (To learn more, see The Industry Handbook: The Airline Industry.)

The Bottom Line
While there has been much controversy over many of the changes to air travel, it doesn't seem to be having a negative effect on the bottom lines of the major airlines. Profits for the first nine months of 2010 for U.S. airlines exceeded $7 billion, topping the full-year profits for every year going back to 1999. Load factors were consistently high all year and reached 86.9% in July, a record for that month.

Data for the entire year promises to be very positive as the last quarter saw airports jammed with passengers throughout the holiday season. That's quite a recovery from just two years ago when a loss of $5.5 billion was booked as demand fell off a cliff and oil surged to almost $150 per barrel.

For the latest financial news, check out Water Cooler Finance: You're Never Too Old To Work.

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