Toeing the Line: The Second Byrne Letter
Following is the complete text of the April 27, 2000, letter from FAA Assistant Chief Counsel, Regulations Division, Donald P. Byrne to Rob Hackman at AOPA. According to FAA spokesman Eliot Brenner, this letter supercedes both the Barton letter/Alkalay memorandum as they apply to FAR 91.109 as well as Mr. Byrne's own previous letter. Also, the letter below applies to any operation conducted under FAR 91.109, not just those within territory covered by the RIC FSDO or within the FAA's eastern region. As referenced in the AVweb article "Toeing the Line: An FSDO Changes the Definition of 'Dual Controls'."
April 27, 2000
Mr. Robert Hackman
Sr. Technical Specialist
Aviation Services Department
Aircraft Owners and Pilots Association
421 Aviation Way
Frederick, MD 21701-4798
Dear Mr. Hackman:
This is a follow-up response to your letter dated April 26, 1999, to the Office of the Chief Counsel, Federal Aviation Administration (FAA), regarding the definition of "dual controls" under 14 CFR section 91.109(a) (section 91.109(a)). Specifically, you asked whether toe brakes are required to be accessible to the right seat of the aircraft when toe brakes are accessible to the left seat of the aircraft or whether it is sufficient that a hand brake or parking brake is accessible to the right seat of the aircraft.
In my letter of response to you, dated July 29, 1999, I addressed the issue of whether the controls accessible to the right seat of the aircraft had to be identical to the controls accessible to the left seat of the aircraft under the definition of "dual controls" (under section 91.109(a)). I stated that the term "dual controls" under section 91.109(a) means that the operating controls accessible to the right seat of the aircraft must be capable of performing the same function as the operating controls accessible to the left seat of the aircraft, not that the operating controls must be identical. I did not address the issue of whether brakes were a required operational control under the definition of "dual controls."
In recent weeks it has come to my attention and the Flight Standards Service (AFS) that this interpretation implies that brakes are required controls under section 91.109(a). It has been long-standing AFS technical position that brakes are not required controls under section 91.109(a). The term "dual controls" under section 91.109(a) refers to flight controls (e.g. pitch, yaw, and roll controls). These flight controls are the only required controls for purposes of meeting the requirements under section 91.109(a).
For years flight instructors have given flight instruction in aircraft that do not have braking systems accessible to both the left and right seat of the aircraft. It was not my intention to change this long-standing technical interpretation of what constitutes "dual controls." I hope this clears up any misleading implications. This interpretation has been coordinated with AFS.
/s/ Donald P. Byrne
Donald P. Byrne
Assistant Chief Counsel