With the announcement this morning that JetBlue will be teaming up with Research in Motion and Yahoo to provide free e-mail and instant messaging on its flights, there are now at least four airlines with announced plans to experiment with in-flight broadband connectivity. In this overview of in-flight Internet capabilities, we take a look at what various airlines say they’ll be offering to their customers in the future, which companies are building their networks, and when we can expect to get full Web connections during those long cross-country flights.

American Airlines

What they’ll be offering: Nationwide in-flight broadband Internet access that extends from the coast to coast. American Airlines passengers will be able to connect to the Web during their flights using any device that has 802.11a/b/g Wi-Fi capabilities.

When it will be offered: American Airlines began testing Wi-Fi capabilities on its fleet of Boeing 767-200 aircraft in August. The goal is to provide broadband service to all passengers starting in 2008.

Who’s building out the network: Aircell, a global airline telecom provider based in Itasca, Ill. Last year, bidding company and Aircell affiliate AC BidCo won the rights to 3-MHz on the 800-MHz spectrum to deliver Wi-Fi connection to airlines. AirCell first demonstrated in-flight WLAN capabilities in 2005.

Alaska Airlines

What they’ll be offering: A satellite-based 802.11b/g Wi-Fi connection for any laptops, smart phones and PDAs. These devices, says Alaska Airlines, will have access to the Internet, e-mail and VPNs, as well as stored in-flight entertainment. The in-flight system will connect to a satellite through an antenna placed atop the aircraft.

When it will be offered: The airline is still testing the Wi-Fi connection on its Boeing 737 aircraft. Ideally, the company hopes to have Wi-Fi connections on all 144 of its planes up and running by spring 2008.

Who’s building the network: Row 44, a Westlake Village, Calif.-based airline telecom provider, which says it can offer in-flight downlink speeds of 81Mbps and uplink speeds of 1.6 Mbps. Because Row 44’s system uses satellite technology, says the company, it will not be limited by international borders and will be available to planes throughout the North American continent. In addition to its Wi-Fi connection services, Row 44 is planning to roll out in-flight entertainment services, such as more than 100 channels of live television.