Conspiracy or coincidence? Flight 93 memorial attacked over crescent shape

United Airlines Flight 93 came in low and fast over this poor Appalachian community, passing directly over a scrapyard where one of the few witnesses to the disaster said the plane was at a tilt and low enough to "count the rivets".

Burnished into the nation's collective memory of 11 September 2001 is the heroism of Flight 93's passengers, who overwhelmed the hijackers and forced them to ditch the plane rather than let them attempt an attack on the US Capitol building 150 miles away.

But disagreement and rancour has dogged efforts to commemorate the 40 victims of terrorism on this Pennsylvania hillside. Seven and a half years after the tragedy, several family members of those who perished say that the planned memorial is in the shape of an Islamic crescent and points directlytowards Mecca.

They complain that a planned "Tower of Voices," a 93ft tall structure that will hold 40 chimes representing the victims of terrorism, is in fact a "minaret".

Tom Burnett, whose son Tom Jnr died in the crash, said of the design that it is "aesthetically wonderful," but "a lot of it contains Islamic symbols". He added: "We ought to just throw the design out and start anew because it really dishonours those who died."

Mr Burnett represents only a minority of the families of Flight 93 but he is not alone in his concerns about the planned memorial, which is not expected to be built until 2010. To the dismay of many, an active community has grown up – online and in the locality – with the sole aim of blocking the memorial in its current form.

The controversy has caused no end of annoyance to local businesses, some of which stand to reap rich financial rewards as the numbers of visitors to the crash memorial grows over time. Already nearly half a million people come to the temporary site.

The straight facts of what happened to Flight 93 are by now widely accepted. The plane hurtled into a reclaimed coal strip mine at 10.03am on 11 September 2001. One witness, Karl Landis, said the plane "rolled slightly to the left and appeared to hit the ground at almost a 90-degree angle".

Another witness, Eric Peterson, said: "It was a massive, massive explosion. Flames and then smoke and then a massive, massive mushroom cloud."

The plane hit the ground at more than 560mph at a 40-degree angle leaving a 115ft wide crater. The fuselage was driven 23ft into the earth and, in the explosion, human remains were scattered over a wide area. Some are still scattered across the crash site to this day.

The 9/11 Commission investigation also concluded that the passengers did not succeed in breaking into the cockpit but that the hijackers crashed the plane when they thought they were about to be overwhelmed.

The story of how the passengers fought back against the terrorists and saved countless other lives, is now part of the national narrative. Tom Burnett Jnr, a father of three young daughters, spoke to his wife Deena from an onboard phone. He said he and his fellow-passengers were "going to do something" despite her protests that he should "Sit down. Be still. Be quiet. Don't draw attention to yourself. Wait for the authorities."

Tom replied: "We can't wait. Deena, if they are going to run this plane into the ground, we're going to do something."

Another passenger, Todd Beamer revealed in a telephone call that passengers were planning a counter-attack. His last words, "Are you guys ready? Let's roll," would become a battle cry for Americans fighting the Taliban and al-Qa'ida in Afghanistan. Even President George Bush has taken to using it in his speeches.

The top of the mountain where the crash occurred was removed many years ago by an opencast coal mining operation. All that is left of the natural landscape is a large bowl. The site of the crash is beside a toxic outfall from a now reclaimed stripmine.

Up the hill, a temporary memorial stands under the flight path of the plane which was bound for San Francisco but had turned back in the direction of Washington DC. Volunteers staff a small wooden hut. Beside it is a wire fence where visitors attach mementos. There are a few flags and a large cross.

With baseball hats and firemen's jackets flapping in the wind, the impromptu memorial carries the signs of the country's anguish over the disaster. There is hardly a surface without a sticker or a note in indelible ink paying tribute to the passengers. It looks down on a fenced off area of "sacred ground," the crash site.

How a planned memorial, for which there were more than 1,000 anonymous submissions and which went through two separate juries before being agreed could end up being described as an "Islamic mosque" remains a mystery for many of those involved.

Part of the blame must lie with Paul Murdoch, architect of the winning design who initially described it as a "Crescent of Embrace". The title caused the internet to erupt with conspiracy theories. Then someone noticed that the arc actually pointed towards Mecca. The fact that this was also the direction to Washington DC was lost on the conspiracy theorists.

The architect quickly agreed to remove "any perceptions relating to Islamic symbolism". The crescent became a circle, with two symbolic breaks, one where visitors will walk along the flight path, the other at the crash scene.

Joanne Hanley, National Parks superintendent for Western Pennsylvania, who is responsible for building the memorial, has little time for the conspiracy theorists. Now that the design of the memorial has been changed to accommodate the critics she is incensed that the controversy still rumbles on.

"It's very upsetting for the families and an unnecessary distraction," she said. "But thank goodness we allow these people to have their say. That, after all, is what the 40 who died on the plane were trying to protect."