There is nothing to suggest that Olsen isn't being truthful about that conversation.
hmm, I'm not so sure about that. If I may be permitted the C&P:
Olson’s Self-Contradictions
Olson began this process of undermining by means of self-contradictions. He first told CNN, as we have seen, that his wife had “called him twice on a cell phone.” But he contradicted this claim on September 14, telling Hannity and Colmes that she had reached him by calling the Department of Justice collect. Therefore, she must have been using the “airplane phone,” he surmised, because “she somehow didn’t have access to her credit cards.”4 However, this version of Olson’s story, besides contradicting his first version, was even self-contradictory, because a credit card is needed to activate a passenger-seat phone.
Later that same day, moreover, Olson told Larry King Live that the second call from his wife suddenly went dead because “the signals from cell phones coming from airplanes don’t work that well.”5 After that return to his first version, he finally settled on the second version, saying that his wife had called collect and hence must have used “the phone in the passengers’ seats” because she did not have her purse.6
By finally settling on this story, Olson avoided a technological pitfall. Given the cell phone system employed in 2001, high-altitude cell phone calls from airliners were impossible, or at least virtually so (Olson’s statement that “the signals from cell phones coming from airplanes don’t work that well” was a considerable understatement.) The technology to enable cell phone calls from high-altitude airline flights was not created until 2004.7
American Airlines Contradicts Olson’s Second Version
However, Olson’s second story, besides being self-contradictory, was contradicted by American Airlines.
A 9/11 researcher, knowing that AA Flight 77 was a Boeing 757, noticed that AA’s website indicated that its 757s do not have passenger-seat phones. After he wrote to ask if that had been the case on September 11, 2001, an AA customer service representative replied: “That is correct; we do not have phones on our Boeing 757. The passengers on flight 77 used their own personal cellular phones to make out calls during the terrorist attack.”8
In response to this revelation, defenders of the official story might reply that Ted Olson was evidently right the first time: she had used her cell phone. However, besides the fact that this scenario is rendered unlikely by the cell phone technology employed in 2001, it has also been contradicted by the FBI.
Olson’s Story Contradicted by the FBI
The most serious official contradiction of Ted Olson’s story came in 2006 at the trial of Zacarias Moussaoui, the so-called 20th hijacker. The evidence presented to this trial by the FBI included a report on phone calls from all four 9/11 flights. In its report on American Flight 77, the FBI report attributed only one call to Barbara Olson and it was an “unconnected call,” which (of course) lasted “0 seconds.”9 According to the FBI, therefore, Ted Olson did not receive a single call from his wife using either a cell phone or an onboard phone.
Back on 9/11, the FBI itself had interviewed Olson. A report of that interview indicates that Olson told the FBI agents that his wife had called him twice from Flight 77.10 And yet the FBI’s report on calls from Flight 77, presented in 2006, indicated that no such calls occurred.
This was an amazing development: The FBI is part of the Department of Justice, and yet its report undermined the well-publicized claim of the DOJ’s former solicitor general that he had received two calls from his wife on 9/11.
http://www.serendipity.li/wot/olson_report_of_phone_calls.htm