In addition to assisting the newly arrived muscle hijackers, the pilots busied themselves during the summer of 2001 with cross-country surveillance flights and additional flight training. Shehhi took the first cross-country flight, from New York to San Francisco and on to Las Vegas, on May 24. Jarrah was next, traveling from Baltimore to Los Angeles and on to Las Vegas on June 7. Then, on June 28, Atta flew from Boston to San Francisco and on to Las Vegas. Each flew first class, in the same type of aircraft he would pilot on Sept. 11.
http://www.nytimes.com/2004/06/17/politics/17ptext.html

The next step for Atta was a mid-July status meeting with Binalshibh at a small resort town in Spain. According to Binalshibh, the two discussed the progress of the plot, and Atta disclosed that he would still need about five or six weeks before he would be able to provide the date for the attacks. Atta also reported that he, Shehhi, and Jarrah had been able to carry box cutters onto their test flights; they had determined that the best time to storm the cockpit would be about 10-15 minutes after takeoff, when they noticed that cockpit doors were typically opened for the first time. Atta also said that the conspirators planned to crash their planes into the ground if they could not strike their targets. Atta himself planned to crash his aircraft into the streets of New York if he could not hit the World Trade Center.

In early August, Atta spent a day waiting at the Orlando airport for one additional muscle hijacker intended for the operation, Mohamed al Kahtani. As noted in Staff Statement No. 1, Kahtani was turned away by U.S. immigration officials and failed to join the operation. On Aug. 13, another in-person meeting of key players in the plot apparently took place, as Atta, Nawaf al Hazmi, and Hanjour gathered one last time in Las Vegas. Two days later, the F.B.I. learned about the strange behavior of Zacarias Moussaoui, who was now training on flight simulators in Minneapolis.

In addition to their last test flights and Las Vegas trips, the conspirators had other final preparations to make. Some of the pilots took practice flights on small rented aircraft, and the muscle hijackers trained at gyms. The operatives also purchased a variety of small knives that they may have used during the attacks. While we can't know for sure, some of the knives the terrorists bought may have been these, which were recovered from the Flight 93 crash site. On Aug. 22, Jarrah attempted to buy four Global Positioning System (G.P.S.) units from a pilot shop in Miami. Only one unit was available, and Jarrah purchased it along with three aeronautical charts.

Just over two weeks before the attacks, the conspirators purchased their flight tickets. Between Aug. 26 and Sept. 5, they bought tickets on the Internet, by phone and in person. Once the ticket purchases were made, the conspirators returned excess funds to al Qaeda. During the first week in September, they made a series of wire transfers to Mustafa al Hawsawi in the U.A.E., totaling about $26,000. Nawaf al Hazmi attempted to send Hawsawi the debit card for Mihdhar's bank account, which still contained approximately $10,000. (The package containing the card would be intercepted after the F.B.I. found the Express Mail receipt for it in Hazmi's car at Dulles Airport on 9/11.)

The last step was to travel to the departure points for the attacks. The operatives for American Airlines Flight 77, which would depart from Dulles and crash into the Pentagon, gathered in Laurel, Md., about 20 miles from Washington, D.C. The Flight 77 team stayed at a motel in Laurel during the first week of September and spent time working out at a nearby gym. On the final night before the attacks, they stayed at a hotel in Herndon, Va., close to Dulles Airport. Further north, the operatives for United Airlines Flight 93, which would depart from Newark and crash in Stony Creek Township, Pa., gathered in Newark. Just after midnight on Sept. 9, Jarrah received this speeding ticket as he headed north through Maryland along Interstate 95, towards his team's staging point in New Jersey.

For reasons that remain unknown, Atta and Omari took a commuter flight to Boston during the early hours of Sept. 11 to connect to Flight 11. As shown here, they cleared security at the airport in Portland and boarded the flight that would allow them to join the rest of their team at Logan Airport.

The Portland detour almost prevented Atta and Omari from making Flight 11 out of Boston. In fact, the luggage they checked in Portland failed to make it onto the plane. Seized after the Sept. 11 crashes, Atta and Omari's luggage turned out to contain a number of telling items, including: correspondence from the university Atta attended in Egypt; Omari's international driver's license and passport; a videocassette for a Boeing 757 flight simulator; and this folding knife and pepper spray, presumably extra weapons the two conspirators decided they didn't need.

On the morning of Sept. 11, after years of planning and many months of intensive preparation, all four terrorist teams were in place to execute the attacks of that day.

On July 20, Hanjour - likely accompanied by Hazmi - rented a plane and took a practice flight from Fairfield, N.J., to Gaithersburg, Md., a route that would have allowed them to fly near Washington, D.C. When Binalshibh pressed Atta to retain the White House as a target during one of their communications in early August, Atta agreed but said he would hold the Capitol in reserve as an alternate target, in case the White House proved impossible. Based on another exchange between Atta and Binalshibh, as late as Sept. 9 - two days before the attacks - the conspirators may still have been uncertain about which Washington target they would strike.