Are you referring to the Whitlow Letter, where in 2000, Whitlow (FAA General Counsel at the time) responded to Capt. Rich Rubin's inquiries about crew rest? Capt. Rubin was a pilot with AMR so his scenarios were those common to passenger carriers. The FAA later did codify crew rest in 12 CFR 121.471 to apply to all flight crewmembers.

In the letter, Whitlow said that a pilot could not depart on a flight if it would end beyond the 16-hour duty day limit. The Air Transport Association (ATA), joined by the Regional Airlines Association (RAA), sued the FAA alleging that what Whitlow did amounted to new rulemaking. The US Court of Appeals, District of Columbia Circuit, denied the consolidated petitions for review.

One thing has always nagged me about the crew rest issue. It's easy to say that 8 hours of flying has been reached and therefore the crew gets a 16 hour rest, but this implies that waiting around for the airport van, checking in at the hotel, etc are included in the 16 hours. I do not believe that is what the law intended.

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