A $300 million renovation and expansion under way at Philadelphia International Airport is doing for Terminals D and E what a similar project did to link Terminals B and C a decade ago.

The additions will bring shopping, new automated baggage sorting, new bag-claim areas, passenger security screening, and new gates to a part of the airport much in need of an upgrade.

By Thanksgiving, a 204,000-square-foot "connector" building will open to travelers between Terminals D and E. It will feature 14 lanes of passenger security screening - along with benches to sit on - and a mall with shops and a view of the airfield.

Best of all, passengers will be able to walk from Terminal A - where international flights come and go - all the way to Terminal E without having to go through security screening more than once.

The concourse at Terminal E is now isolated behind its own security checkpoint.

Gone will be the cramped, jury-rigged security lanes at D and E. In their place will be an art exhibit, 16 stores and, officials hope, a Silver Diner restaurant.

At the end of Terminal E - home to Southwest and Northwest Airlines - a fan-shaped extension that will have seven gates for aircraft and a 350-foot, curved-glass wall is about to take shape. Construction is to start this month. In a central rotunda of the expanded terminal, light will stream onto an art exhibit of clouds.

The expanded terminal will be finished in October 2009.

The improvements and renovations will do for Southwest, AirTran, United, Northwest, Continental and Air Canada - all of which fly out of D and E - what the $139 million renovation to B and C did in 1998 for US Airways, officials said.

"We wanted to raise the bar for the traveling public and enhance safety and security at the same time," said architect Kent Lessly, of Philadelphia's Daroff Design Inc. The design team came up with the idea of putting a building between the existing terminals. "Real estate at the airport is in short supply. It was a prime spot," Lessly said.

Starting the week before Thanksgiving, passengers who fly out of D and E will be ticketed in the lobby and head up escalators to the 14 new security-checkpoint lanes. Currently, there are four security lines in D and four in E.

A floor below the security checkpoints, a 40,000-square-foot, automated baggage-screening system with high-technology explosives-detection machines will screen bags at a rate of 750 an hour, compared with 150 if handled by baggage attendants. The new baggage system will be ready by spring.

Passengers leaving security will spill onto a row of shops that will flank a 90-foot-wide wall of glass overlooking the airfield. Ten shops already signed up include Vino Volo, a wine bar and tasting room; Peet's Coffee; Borders books; and Tech Showcase, a wireless-gadget store.

Also by spring, the expansion will include a new D-E baggage-claim building that will connect the existing D-E baggage claims and have nine carousels, as well as renovated and expanded D and E ticket lobbies.

The tab for the improvements will be paid by airport revenue bonds funded by the airlines and "passenger facility charges," said deputy aviation director Mark Gale, in charge of operations and facilities.

About $153 million will come from airport revenue bonds and $147 million from passenger facility charges, which are fees of up to $4.50 imposed on departing passengers to use on Federal Aviation Administration-approved projects.

In the future, airport officials want to link Terminal F so that passengers will be able to walk from A to F and go through security only once. "But that's not this project," Gale said.

Since 2001, the Philadelphia airport, North America's 10th-busiest, has opened two new terminals - the international terminal A-West and Terminal F for regional and commuter flights. With those additions, the terminal complex nearly doubled, spurred by more demand and the arrival of the low-fare airlines AirTran and Southwest.

The expansion of Terminal E had its genesis in 2002 with a $20 million renovation to Concourse D and Terminal D, said city acting aviation director Charles Isdell.

"At the time, we did it specifically to encourage low-fare competition, to encourage new airlines to come here," Isdell said. After AirTran added more flights, space became cramped in Terminal D.

With the arrival of Southwest in 2004, the need became pressing to renovate Terminal E and "fix up some of the unfinished pieces in D," he said.

At the same time, he said, the security checkpoints "had become a big deal after Sept. 11, 2001. We had what we thought was an inadequate infrastructure for security screening of passengers."

It was back to the drawing board and a new design.

The size of the project doubled and the idea emerged to turn D and E "into a module" for other carriers the "way we did with B and C in the 1990s" for US Airways, Isdell said.

Looking to the future, the airport plans to put automated explosives-detection equipment in Terminals A-East, B, C and F for outbound baggage. Terminal A-West currently has such equipment. "And we're exploring ideas on how to expand and enhance" the security checkpoints at B and C, Isdell said.

But at the moment, with oil at $130 a barrel, all airlines are "taking a closer look at debt service" for future projects.

"There may be some postponement, or slowdown, of some of these future capital projects," Isdell said. The current projects are already funded. "We may not start the financing of new projects as quickly, but anything we've already got the money for is a go."

Contact staff writer Linda Loyd at 215-854-2831 or lloyd@phillynews.com.