Updated

Designers of a Flight 93 memorial have made a bowl-shaped piece of land its centerpiece, replacing a crescent-shape design that some critics had said was a symbol honoring terrorists, officials announced Wednesday.

The new design for the memorial, to be built on the site of the Sept. 11, 2001, crash near Shanksville, features most of the details of the original, which was unveiled in September after a worldwide design competition.

But a round, bowl-shaped area would replace a "Crescent of Embrace," a crescent-shaped cluster of maple trees.

In September, Rep. Tom Tancredo, R-Colo., criticized the design in a letter to the National Park Service Director, saying many questioned the shape "because of the crescent's prominent use as a symbol in Islam — and the fact that the hijackers were radical Islamists."

Paul Murdoch, president of Paul Murdoch Architects, which designed the memorial, had called the criticism of the crescent an "unfortunate diversion," but said they were sensitive to the concerns.

In both old and new versions of the design, a tower with 40 wind chimes welcomes visitors to the site, where they can then walk to a large circular field ringed by 40 groves of red and sugar maple trees, symbolizing the 40 passengers and crew who died. There will also be pedestrian trails, a plaza from which to view the crash site, and a white marble wall with the victims' names inscribed.

In the Flight 93 National Memorial's newsletter, Murdoch described the new design as an "evolution" of what was announced two months ago, reflecting input from the public, the competition's jury and others.

The circle enhances the earlier design by putting more emphasis on the crash site, officials said in the newsletter. A break in the trees will symbolize the path the plane took as it crashed.

Flight 93 was flying to San Francisco from Newark, N.J., when it became the last of four planes hijacked that day and the only one not to kill anyone on the ground. The official 9/11 Commission report said the hijackers crashed it as passengers, aware of the previous hijackings, tried to take control of the cockpit. The crash site is about 65 miles southeast of Pittsburgh.

The original design was selected by a jury of 15 made up of design professionals and family and community members and was narrowed down from a pool of 1,011. A projected date for the opening has not been set.