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9-11 Archive 2003

Is the Pentagon Mystery Disc from a Global Hawk?

October 12, 2003

An official FEMA photograph reveals a crucial piece of evidence, which if positively identified, could prove what kind of aircraft hit the Pentagon on Sept. 11, 2001.

The photograph is one of many taken by Jocelyn Augustino, a FEMA photographer, at the Pentagon crash site on Sept. 13, 2001. In the FEMA on-line photo library, the best photos of the unidentified disc are numbered 4414 and 4415, archived at: http://www.photolibrary.fema.gov/photolibrary/advancedsearch.do

Several readers have suggested that the unidentified disc was a piece from the Auxiliary Power Unit (APU) mounted in the tail section of a Boeing 757. Honeywell makes the GTCP331-200 APU used on the 757 aircraft. No one, however, claimed that the small disc was a piece from one of the main engines of a 757-200.

I contacted Honeywell’s Aerospace division in Phoenix, Ariz., and sent high-resolution photos for their examination. “There’s no way that’s an APU wheel,” an expert at Honeywell said. The expert, who cannot be named, added: “That turbine disc—there’s no way in the world that came out of an APU.”

I also contacted Pratt & Whitney and Rolls Royce, manufacturers of the 757’s turbofan jet engines to try and identify the piece. “If the aircraft that struck the Pentagon was a Boeing 757-200 owned by American Airlines, then it would have to be a Rolls Royce engine,” Mark Sullivan, spokesman for Pratt & Whitney, said.

John W. Brown, spokesman for Rolls Royce (Indianapolis), said, “It is not a part from any Rolls Royce engine that I’m familiar with, and certainly not the AE 3007H made here in Indy.” The AE 3007 engines are used in small commuter jets such as the Cessna Citation; the AE 3007H is also used in the military’s unmanned aircraft, the Global Hawk. The Global Hawk is manufactured by Northrop Grumman’s subsidiary Ryan Aeronautical, which it acquired from Teledyne, Inc. in July 1999.

If the government version that an American Airlines 757-200 hit the Pentagon is accurate, then the object in the photo should be a part of a Rolls Royce RB211-535 turbofan engine. When I told Brown that it must be a piece of a Rolls Royce engine, Brown balked and asked who at Pratt & Whitney had provided the information.

Asked again if the disc in the photo is a piece of a Rolls Royce RB211-535, or from the AE 3007 series, Brown said he could not answer. I asked Brown if he was actually familiar with the parts of an AE 3007H, which is made at the Indiana plant: “No,” Brown said. “I don’t build the engines. I am a spokesman for the company. I speak for the company.”

Rolls Royce produces the RB211-535 engines for American Airlines 757-200 aircraft at a plant in Derby, England. Martin Johnson, head of communications at Rolls Royce in Derby, said he had followed my story closely and had been notified in advance by Rolls Royce offices in Seattle and Indianapolis. Rather than address the question of the unidentified disc, however, Johnson launched a verbal attack on me for questioning the government version of events at the Pentagon on 9-11. “You are the only person in the world who does not believe that a 757 hit the Pentagon,” Johnson said, “The idea that we can have a reasonable conversation is beyond your wildest dreams,” he said and hung up the phone.

Flug Revue, a German magazine about aviation equipment was more willing to discuss the disc. Karl Schwarz, a technical editor at the Bonn-based publication, examined the photo and technical drawings of the RB211-535. “I think only an engineer who is involved in the design of the engine could identify the part,” Schwarz said.

While the front fan of the RB211-535 has a 74.5-inch diameter, compression discs inside the engine are much smaller. Schwarz said the inner discs are between 29 and 41 inches in diameter. “It could well be” an inner compression disc, Schwarz said. The discs from the inner stages are made of titanium, he added. I asked Schwarz if this could be a disc from a smaller engine, such as the Global Hawk’s AE 3007H. “It could come from any jet engine,” Schwarz said.

If the disc in the photo can be matched with a Rolls Royce AE 3007H engine, it would prove something like a Global Hawk hit the Pentagon. The Global Hawk engine is hand built at the Rolls Royce plant in Indianapolis and has an opening diameter of 43.5 inches. Schwarz said he did not have a technical diagram of an AE 3007 engine to consult.

Because the disc in the photo appears very similar in size and shape to the front fan of a Global Hawk engine, I asked Schwarz in what position is the solid disc found behind the front fan of a turbofan engine. “Immediately,” Schwarz said.

An unnamed former cruise missile engineer for the engine manufacturer Teledyne Continental Motors-Turbine Engines said, “Clearly, the part in the picture is larger than 24 inches in diameter. It also appears to have a nosepiece-like device on its front. This probably houses bearings, front oil sump and perhaps an alternator or starter.”

“This fan did not come from a cruise missile engine,” the engineer concluded.