I'm a over planner, so I decided to contact the TSA about traveling with a cooler as luggage. Here is their response (in only 48 hours time) (sorry for the long message, but the details are important):
"Thank you for your e-mail regarding the Transportation Security Administration's (TSA) policies on traveling with ice and/or gel packs in checked luggage.
TSA permits regular ice, frozen gel packs, and dry ice in checked baggage. Frozen items are allowed so long as they are solid and in a "frozen state" when presented for screening. If frozen items are partially melted or have any liquid at the bottom of the container, the ice/liquid container must meet 3-1-1 requirements. More specifically:
Checked Baggage: Regular ice and frozen gel packs are not restricted by TSA. When regular ice is transported, TSA recommends a cooler. For dry ice:
. TSA requires that its packaging must permit the release of carbon dioxide gas;
. The Federal Aviation Administration (FAA) limits each piece of checked baggage to five pounds of dry ice;
. The FAA requires that each package of dry ice be marked "DRY ICE" or "CARBON DIOXIDE SOLID;" and
. The FAA requires that each package of dry ice be marked with the net weight of the dry ice or an indication that the amount of dry ice is five pounds or less.
TSA recommends travelers contact their airlines to inquire about any additional guidelines the airlines may have regarding traveling with either regular ice or dry ice. It is important to note that TSA enforces all FAA requirements pertaining to dry ice.
Concerning packages and containers sealed with tape and traveling as checked baggage, in accordance with TSA regulations, a package or container sealed with tape is not a prohibited item. Transportation Security Officers (TSOs) are required by law to screen all checked baggage for prohibited items. If a checked bag sounds an alarm, it may be physically searched. If a TSO must conduct a physical inspection of a sealed package to resolve an alarm during screening, the TSO will reseal the package once the inspection is complete.
If the TSO finds any prohibited items in the sealed package, the items will be removed and the package resealed. There is no need for passengers to place their own sealing tape inside the packages or containers. All checked baggage should be closed or sealed before checking them with the airlines.
Security screening at foreign airports is beyond TSA jurisdiction. Travelers must go through different clearance procedures when crossing international borders. Passengers and their baggage are also screened for security according to standards established by the Government of that country. As a sovereign entity, that country may establish its own security requirements for airports and air carriers that are not necessarily the same as those required in the United States."
http://www.tsa.gov/travelers/airtravel/ ... items.shtm
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From US Airways
"Dry Ice will be accepted as checked or carry on baggage under the
following conditions. The package weight is 5.5 lbs of dry ice or less
per package. The package must be designed to permit the release of CO2
gas so that the pressure does not build up. For checked baggage the
package needs to be marked with the words "Dry Ice" or "Carbon Dioxide
Solid" and the net weight of the dry ice. "
