June 4, 2012

Rebecca B. MacPherson, Esq.

Assistant Chief Counsel for Regulations, AGC-200

U.S. Department of Transportation

Federal Aviation Administration

800 Independence Avenue, S.W.

Washington, D.C. 20591

Dear Ms. MacPherson,

I am submitting the questions that follow on behalf of the Allied Pilots Association regarding 

the new 24 CFR Part 117 regulations. It is our hope that these questions will be helpful in 

resolving any ambiguity and uncertainty regarding the application of portions of the rule and 

aid in a smooth transition to the new procedures. Please feel free to contact me for any further 

information or clarification you might require.

Email: dpinion@alliedpilots.org

Work: 817-302-2325

Cell: 817-846-3070

//Signed//

Douglas Pinion

Chairman, Flight Time / Duty Time Committee

Allied Pilots Association

Captain, American Airlines
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§ 117.3 Definitions.

Theater & Acclimation – The following deal with the Theater definition and 

Acclimation.

1. When you change theaters, what time zone from the original theater do you use to 

enter the FDP Limit and Maximum FT Tables until you acclimate to the new theater?

2. When a pilot changes theaters but does not remain in the same time zone for 36 or 72 

hours in the new theater, does the pilot acclimate? If so, when and to what time zone? 

If you do not acclimate, do you continue to use Home Base Time to enter the FDP 

Limit and Flight Time tables?

3. A pilot is on a pairing that departs the US and is scheduled for a 24-hour layover in a 

European city, which would result in a change in theater. Due to a mechanical 

problem or cancelled inbound flight, the layover is extended to 48 hours. Under these 

circumstances, it is possible that the cancellation takes place after pilot’s sleep period 

that was planned and timed based on not being acclimated. Is it the intent of the 

regulations that this pilot would now become acclimated and enter the FDP and FT 

Tables using local time with no reduction for not being acclimated or must the rest 

period have been originally scheduled for more than 36 hours to become acclimated in 

less than 72 hours?

To simplify this portion of the regulations, a possible solution to consider is that, when 

remaining in the same theater, use HBT to enter the charts unless in a new time zone

(theater) for more than 72 hours. Then use that time zone as the new acclimated time 

zone. When changing theaters, use HBT to enter the Tables unless you remain in the new

theater for more than 72 hours. If you remain in the same new theater (identified by the 

time zone where you first had a layover), use local time in the new theater after 72 hours

and be considered as acclimated. This would more realistically follow the body’s 

circadian rhythm and would solve the problem (and restrictions) that exist of being nonacclimated upon return to the US following a layover of longer than 36 hours in Europe or 

Asia. There are quite a few 48-hour layovers in international operations due to less than 

daily service to many locations. In these situations, the scientific recommendation is to 

attempt to stay on home base time since you will be returning to that theater and have no 

intention of acclimating and remaining in the new theater. If you do not stay in the same 

new time zone, use local time in the new theater but apply the following duty period 

penalty for not being acclimated – three hours for non-augmented, one hour for 

augmented. Use HBT for the first 72 hours; thereafter use local time.

4. In the final rule and subsequent correction, the FAA defined a change in theater as a 

change of more than 60 degrees of longitude, removing the time zone consideration 

entirely rather then using a combination of time zone and longitude. As a result of this 

decision, a pilot flying from DFW to HNL (Honolulu) would change theaters due to a 

change of just over 60 degrees, while a pilot flying from DFW to OGG (Maui), which 

is just less than 60 degrees of change, would not. Both locations are five hours time 
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difference from DFW. Is it the FAA’s intent that two sets of pilots operating between 

DFW and these cities in the same time zone and in close proximity to each other be 

treated differently with regard to change in theater?

Suitable Accommodation

5. Does the definition of “suitable accommodation” apply to a layover facility? If so, is it 

the FAA’s intent that reclining chairs in a room with multiple chairs and multiple 

individuals resting is considered suitable for the rest and uninterrupted sleep 

opportunity required under paragraph 117.25? If not, what must a layover facility

consist of?

Physiological Night’s Rest

6. In the NPRM, the FAA proposed a definition that included the hours of 0100 to 0700, 

just as in the final rule. However, in the NPRM, the rest period was defined as at the 

rest location. Since that changed in the final rule, the rest period could included travel 

time, etc. that encroaches on the 0100-0700 time frame. Is it the FAA’s intent that the 

eight hours of uninterrupted sleep opportunity should include the hours of 0100 and 

0700?

§ 117.11 Flight time limitation.

1. This question is regarding the flight time limit in a duty period and the affect of 

underly, overfly and the planned flight time for the day versus the original 

schedule. The original FDP is planned unaugmented.

The flight time limit is 9 hours for a particular FDP with 4 legs. The FDP was 

originally scheduled for 8:30 of flight time. At the end of leg two, the total of flight 

time actually flown and remaining scheduled time is 9:05.

a. May the crew depart on leg three with the remaining flight time on leg 

four scheduled to exceed nine hours in the FDP? If not, what must be done 

to allow the crew to depart on leg three?

b. If the total of flight time flown and remaining schedule did not exceed nine 

hours until after leg three, but the flight plan for that day for leg four is 

less than scheduled and would keep the total below nine hours, may the 

crew depart on leg four?

c. May augmentation be used on a FDP already in progress to allow 

additional flying beyond the originally scheduled unaugmented flight time 

and FDP limits even though the relief pilot was not aboard to provide 

breaks on previous legs in the FDP?

2. In Part 117, the FAA decided not to change the definition of flight time from that 

which previously exists in Part 1. With that in mind, consider the following. In 

each example, the aircraft is a normally scheduled flight and is loaded with 

passengers and crew with the intent to depart for a different destination. 
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 Aircraft A powers back from a gate, taxis to a holding spot on the ramp 

a short distance from the gate and shuts down engines for a one-hour 

weather departure delay, then restarts engines and taxis for takeoff.

 Aircraft B pushes back from an adjacent gate, starts engines and taxis a 

short distance to an adjacent holding spot on the ramp and shuts down 

for the same one-hour delay and then restarts engines and taxis for 

takeoff.

 Aircraft C pushes back from the gate all the way to an adjacent holding 

spot on the ramp for the same one-hour delay prior to starting engines

and continuing taxi for takeoff.

a. For the purposed of the flight time limitations in 117.11, would the flight 

time for the pilots operating each of these aircraft be calculate differently?

§ 117.13 & 117.17 Flight duty period: Unaugmented and Augmented operations. 

7. What time zone do you use for daily duty period and flight time limits when entering 

Tables A and B, when remaining in the same theater starting consecutive Flight Duty

Periods in different time zones. For example, would a pilot based in LAX but on a 

layover in LGA use Pacific Time or Eastern Time for establishing duty and flight time 

limits for the FDP following the layover? In the NPRM, the charts were labeled HBT 

or Acclimated. However, the HBT was removed in the final rule. Using local time 

(Eastern in this example) to enter the tables would significantly compromise the 

intended protections should a pilot commence an early morning FDP. Using Table B, 

a 0700 local start time would allow a pilot to have a 14 hour FDP with nine hours of 

flight time when the reality is that the pilot actually signed in at 0400 HBT (body

time) and awakened at 0300 or earlier. Is this the FAA’s intent?

8. The FDP limit charts refer to “Scheduled Time of Start.” If you receive a call at home 

(within a few hours of the originally scheduled report time) that delays your report 

time, is this new report time considered a new “Scheduled Time of Start” for the 

purpose of establishing a FDP and flight time limit or are the limits based on the 

original report time? If not, would a minimum rest period be required between 

notification of the delay and time of start to establish a new “Time of Start?”

9. A pilot is originally scheduled for an unaugmented FDP with four landings and a start 

time of 0600, which would allow a planned FDP of up to 12 hours. If the pilot diverts 

to an alternate due to weather on the last leg with the intent of continuing on to 

destination following refueling, would the FDP limit now be based on five landings 

and thus only 11.5 hours in this case? Would any operational extension also be based 

on 11.5 hours as well?

10. These questions are regarding the flight time limit in an unaugmented FDP and the 

affect of underfly and overfly, and the planned flight time for the day versus the 

original schedule. Based on the Time of Start, the flight time limit is 9 hours for a 
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particular FDP with 4 scheduled legs. The FDP was originally scheduled for 8:30 of 

flight time and four legs. 

a. At the end of leg two, the total of flight time actually flown and scheduled time 

remaining is 9:05. May the crew depart on leg three with the remaining flight 

time on leg four scheduled to exceed nine hours in the FDP? If not, what must 

be done to allow the crew to depart on leg three?

b. If the total of flight time flown and remaining schedule did not exceed nine 

hours until after leg three, but the flight plan for that day for leg four is less 

than scheduled and would keep the total below nine hours, may the crew 

depart on leg four?

c. May augmentation be used on a FDP already in progress to allow additional 

flying beyond the originally scheduled unaugmented flight time and FDP 

limits even though the relief pilot was not aboard to provide breaks on previous 

legs in the FDP?

§ 117.21 Reserve status.

11. Must reserve duty be physically on airport property to be classified airport or 

standby reserve or does sitting reserve at another location near the airport, such 

as a nearby hotel or similar facility designated by the operator, apply as well?

12. Reserve – 117.21 (c) (2) refers to rest requirement for reserves that “complete” a 

RAP. 

a. What rest requirement applies to a reserve pilot that is released from a 

RAP without serving the entire 14 hours in order to be given an earlier 

assignment the following day? In other words, what is meant by 

“completes a RAP?”

b. Once assigned a RAP, must a pilot either serve the entire RAP or be given a 

flight assignment, or may the pilot be released from the RAP to be given an 

earlier RAP or flight assignment the following day? 

c. If the pilot can be released, this could result in a complete circadian 

reversal for the pilot with little opportunity to obtain sleep during the 

intervening rest period provided due to the timing of that rest period. Is 

there any requirement to obtain a physiological nights rest prior to 

further assignment under these circumstances?

13. A pilot is assigned as a reserve to a RAP. After three hours of being on call in the 

RAP, the pilot is contacted to report for a FDP of 10 hours, all of which is legal 

and in compliance with the applicable provisions of Part 117. 

a. How much of this time would count toward the weekly FDP limitation of 

60 hours – 10 hours or 13 hours?

b. What is the answer in a. if the time spent on call is airport standby instead 

of short call?
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§ 117.25 Rest period.

14. What exactly is meant by “eight hours of uninterrupted sleep opportunity?” For 

example, on a layover, if an individual takes 30 minutes to check in and prepare 

for bed after arriving at a hotel and 45 minutes to shower, dress, pack, etc. in the 

morning and an additional 45 minutes to obtain something to eat and then check 

out of the hotel, would the minimum time at the hotel under the circumstances 

described be ten hours in order to provide an eight hour uninterrupted sleep 

opportunity?

15. If, during the eight hour uninterrupted sleep opportunity, a fire alarm sounds at a 

hotel or hotel staff knocks on the door or the certificate holder scheduling 

department contacts the pilot by phone, would the eight hours of uninterrupted 

sleep opportunity be required to start over from that time?

16. If a pilot is scheduled for back-to-back pairings on consecutive days, is the pilot 

required to have an eight-hour uninterrupted sleep opportunity at home or other 

resting location between the consecutive pairings?

17. Must the 30-hour rest period required in 117.25(b) be prospectively identified? 

In other words, can a rest period that is scheduled for less than 30 hours and that 

is already in progress be extended beyond 30 hours to satisfy the requirement in 

117.25(b)?