The company also plans to offer WiFi on Northwest Airlines planes. The two airlines are in the process of merging. For flights longer than three hours, the service will cost $12.95; under three hours the price will be $9.95.
There will be some restrictions: Delta will block websites containing pornography or other content it deems inappropriate to view in public. Internet phone calls will be also be blocked, to comply with Federal Aviation Administration rules.
The airline hopes WiFi will make its shuttle service more attractive to business travelers who need Internet access. Many favor Amtrak because they can use their own WiFi and cellphone services aboard the trains.
"We would hope that would make us more competitive," said Chris Babb, Delta's product manager of in-flight entertainment and media. "It's been the most requested product that our customers have asked for over the last couple of years."
Nicole C. Wong can be reached at nwong@globe.com.