Here's an FAA Legal interpretation from 1993. It's pretty lengthy, but I think it has enough information to answer your question.
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April 9, 1993
Andrew Donahue
This is in response to your request for an interpretation dated August 6, 1992.
You ask what conditions must be met for a flight to be conducted under FAR Part 135 versus Part 91. You give the following example:
A flight is dispatched from Memphis to El Paso to pick up freight and deliver to Kansas City. The flight then returns to Memphis. The leg from Memphis to El Paso is empty. The leg from El Paso to Kansas City carries cargo. The leg from Kansas City back to Memphis is empty.
You then ask:
If the "assignment" is to fly from Memphis to El Paso to Kansas City, then back to Memphis, are the flights from Memphis to El Paso, and from Kansas City to Memphis considered operations conducted under Part 91 or Part 135?
Additionally, you state:
The company will sometimes dispatch a flight with enough duty time to get to a destination (i.e., Memphis to Newark, NJ) and then want the crew to Part 91 the aircraft back to Memphis or "re-position" the aircraft back to its base. Can this be done simply because the aircraft is empty, or must other conditions be met (i.e., non-revenue versus revenue)?
Section 135.1 provides in pertinent part that:
(a) Except as provided in paragraph (b) of this section, this part prescribes rules governing -
(3) The carriage in air commerce of persons or property for compensation or hire as a commercial operator...
(b) ...this part does not apply to - ...
(3) Ferry or training flights....
A ferry flight is defined in the Airman's Information Manual (AIM) glossary as:
- A flight for the purpose of:
1. Returning an aircraft to base
2. Delivering an aircraft from one location to another
The issue is whether the Part 135 flight or "assignment" is completed when the cargo is unloaded at the destination airport. The purpose of the flight conducted under Part 135 is to deliver freight to the destination airport. The ferry flight to return the aircraft to the base of operations changes the purpose to re-positioning the aircraft under Part 91. A flight conducted for the purpose of re-positioning an aircraft under Part 91, after the completion of an assigned flight conducted under Part 135, cannot be considered a new assignment under Part 135 and, therefore, is not subject to the flight time limitations and rest requirements of Part 135.
The general rule with respect to flight time limitations of Part 135 is that any "other commercial flying" (e.g., flights conducted under part 91) must be counted against the daily flight time limitations of Part 135 if it precedes the flight conducted under Part 135. However, if the Part 91 flight occurs after the Part 135 flying, the Part 91 flight is not counted against the daily flight time limitations of Part 135.
The first leg from Memphis to El Paso delivers an aircraft from one location to another. It repositions. It is a ferry flight conducted under Part 91. However, because it precedes a Part 135 leg, flight time accumulated on the first leg must be counted toward Part 135 flight time for the 24 hour period.
The second leg from El Paso to Kansas City is a cargo flight conducted under Part 135.
The third leg from Kansas City to Memphis is returning the empty aircraft to home base. It is also considered a ferry flight conducted under Part 91. Because the flight time accumulated on the third leg occurs after the Part 135 flight is completed it does not count against Part 135 flight time limitations for that 24 hour period.
All Part 91 commercial flight time is counted against the pilot's quarterly and yearly flight time limitations. However, please note that if, for example, the pilot has reached the yearly flight time limit for Part 135 operations, the pilot can nonetheless continue to fly under Part 91 in that calendar year. "Other commercial flying" under Part 91 is counted to the calendar year limit only if a subsequent Part 135 operation is conducted in that calendar year. We enclose a copy of an interpretation dated October 9, 1990, issued to Mr. Steve Wolff. That interpretation concerns Part 121 operations, but the analysis concerning yearly flight time limitations and other commercial flying is applicable here.
The general rule regarding rest requirements is that if the Part 91 flying is assigned by the certificate holder, it may not be conducted during a required rest period. Since your example involves a Part 91 operation, required by the certificate holder, it may not be conducted during the required rest period and, therefore, may affect the availability of the crew for the next Part 135 operation.
You also ask a question regarding rest periods. You state:
My company believes they can have a crew member in rest (getting legal) and at the same time have the crew member on a beeper in case a trip comes up within their remaining duty time. I believe this is in direct conflict with 135.263(b).
The Federal Aviation Administration (FAA) has consistently interpreted "rest" requirements to be satisfied only if the rest time is determined prospectively, is continuous, is free from all duty and restraint, and is free from the responsibility for work should the occasion arise. A period when a pilot has a present responsibility for work, if called, does not qualify as a rest period. This should be contrasted with a pilot who does not have a present responsibility to fly, if called. For example, when called, he is merely notified of a flight assignment that is to take place at the conclusion of his rest period.
Recently, a development has occurred concerning reserve status and standby issues. Enclosed is a copy of a letter from Anthony J. Broderick, Associate Administrator for Regulation and Certification, to Mr. James Landry, President of the Air Transport Association of America. In that letter, Mr. Broderick announced that a study is being conducted in order to allow the FAA to reappraise its position on reserve status and standby issues.
During this period of reappraisal, Flight Standards Service would like to have the benefit of your views and experiences on these important issues. A letter describing your reserve and standby experiences, and stating your opinions on the issues can be sent to the following address:
Air Transportation Division, AFS-200
Flight Standards Service
Federal Aviation Administration
800 Independence Avenue, SW
Washington, DC 20591
Re: "Reserve" and "Standby" study.
This interpretation was written by Thomas Kiely and Arthur E. Jacobson of the Operations Law Branch, AGC-220. It has been reviewed by Joseph Conte, Manager of the Operations Law Branch and it has been coordinated with the Air Transportation Division of the Flight Standards Service .
Sincerely,
Donald P. Byrne
Assistant Chief Counsel
Regulations and Enforcement Division
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