The new seats will feature pitch of at least 34 inches or more. Delta's standard Economy Class seat pitch is currently 31 inches. In...

Delta Air Lines is planning to introduce “Economy Comfort” – a premium-economy cabin product launched on long-haul international flights earlier this year – to its entire mainline fleet of more than 550 aircraft, in addition to more than 250 two-class regional jets.

“Our goal is to make sure premium customers are sitting in premium seats,” says Richard Anderson, Delta Air Lines’ chief executive officer. “Delta already offers more First Class seats than any other U.S. airline and by expanding Economy Comfort we’ll offer customers even more opportunities to select a premium seat.”

The new seats will feature pitch of at least 34 inches or more. Delta’s standard Economy Class seat pitch is currently 31 inches. In addition to more leg room, customers seated in Economy Comfort will receive priority boarding.

Among the many aircraft types in Delta Air Lines' massive fleet is a fleet of McDonnell Douglas-legacy Boeing MD-90 jets, which have extremely quiet cabin interiors. Delta has operated 21 of the type on domestic routes but according to Wikipedia has agreed to buy 13 more used examples from other airlines, to give it the world's largest fleet of MD-90s

The premium-economy class seats will be installed in the first three-to-five rows of the Economy cabin by removing a negligible number of seats from the current cabin configuration on all of Delta’s domestic Boeing 767, 757, 737, MD-88, MD-90, DC-9, Airbus A320 and A319 aircraft, and all two-class regional jets including the CRJ900, CRJ700, Embraer 170 and Embraer 175 aircraft types by summer 2012.

Delta says the breadth of this installation means flights to Canada, Mexico, the Caribbean, Central and northern South America will also offer the Economy Comfort product. The first of these converted aircraft will be a Boeing 757, which will enter service with the new seats in November.

Customers who have purchased an Economy ticket on Delta will be able to choose Economy Comfort seats for an additional introductory fee of $19 to $99 on a one-way itinerary including Alaska, Hawaii and short-haul international markets. Economy Comfort seats can be reserved through, kiosks, and Delta reservations beginning in late spring for travel in summer 2012.

As with Delta’s long-haul international Economy Comfort product, complimentary access to domestic and short-haul international seats will be available at booking to all SkyMiles Diamond and Platinum Medallion members and customers purchasing full-fare Economy class tickets.

Gold Medallion members will also have free access to these seats at time of booking, while Silver Medallion members can purchase them at a 50 per cent discount off the fee at time of purchase or can access these seats for free at check-in.