[Federal Register Volume 76, Number 73 (Friday, April 15, 2011)]
[Proposed Rules]
[Pages 21270-21272]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-9236]



Federal Aviation Administration

14 CFR Part 121

[Docket No. FAA-2011-0367]

Interpretation of Duty and Rest Provisions for Maintenance 

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Proposed interpretation.


SUMMARY: This draft letter of interpretation addresses a request by the 
Aeronautical Repair Station Association (ARSA) to rescind a letter of 
interpretation issued May 18, 2010 which clarified what activities may 
constitute duty for maintenance personnel and the application of the 
rest provisions under 14 CFR 121.377. The FAA requests comment on the 
May 18, 2010 proposed response to United Technologies Corporation.

DATES: Send your comments on or before June 14, 2011.

ADDRESSES: You may send comments identified by Docket Number FAA-2011-
0367 using any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30; U.S. 
Department of Transportation, 1200 New Jersey Avenue, SE., Room W12-
140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.

    For more information on the rulemaking process, see the 
SUPPLEMENTARY INFORMATION section of this document.

    Privacy: We will post all comments we receive, without change, to 
http://www.regulations.gov, including any personal information you 
provide. Using the search function of the docket Web site, anyone can 
find and read the electronic form of all comments received into any of 
our dockets, including the name of the individual sending the comment 
(or signing the comment for an association, business, labor union, 
etc.). You may review DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78) or you 
may visit http://DocketsInfo.dot.gov.
    Docket: To read background documents or comments received, go to 
http://www.regulations.gov at any time and follow the online 
instructions for accessing the docket or Docket Operations in Room W12-
140 of the West Building Ground Floor at 1200 New Jersey Avenue, SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Anne Bechdolt, Attorney, Regulations 
Division, Office of Chief Counsel (AGC-220), Federal Aviation 
Administration, 800 Independence Avenue, SW., Washington, DC, 20591; e-
mail: [email protected]; telephone 202-267-3073.

SUPPLEMENTARY INFORMATION: On December 13, 2010, ARSA requested the FAA 
withdraw a legal interpretation issued on May 18, 2010 to United

[[Page 21271]]

Technologies Corporation (May 18, 2010 interpretation). The legal 
interpretation addressed what types of activities may be considered 
part of the duty period for maintenance personnel under Sec.  121.377. 
In addition, the legal interpretation provided that the FAA would not 
consider compliant a work schedule in which maintenance personnel were 
required to work several consecutive weeks without an uninterrupted, 
consecutive 24-hour rest period during any seven consecutive days. This 
interpretation clarifies the limitations of the equivalency standard in 
Sec.  121.377 resulting from two conflicting legal interpretations. 
Compare Legal Interpretation 1987-15 (June 14, 1987) (noting that the 
flexibility in Sec.  121.377 was intended to apply only in cases of 
national emergency or unusual occurrence in the air carrier industry) 
with Legal Interpretation to Ron Webb from Donald P. Byrne, Assistant 
Chief Counsel, Regulations (June 21, 1991) (noting that ``the term ``or 
equivalent thereof'' allows for time off (in 24 consecutive hour 
increments) to be deferred or accumulated, making it possible to take 
four 24 hour periods off toward the end of a calendar month''). ARSA 
asserts that the May 18, 2010 interpretation changes the plain language 
of the regulation and requests that it be withdrawn. The FAA has 
decided against withdrawing the May 18, 2010 interpretation at this 
time. However, based on ARSA's request, the agency has decided to seek 
comment on the impact of the interpretation. Based on a review of the 
comments, the FAA may decide to modify or rescind the May 18, 2010 
    The FAA believes that this type of schedule (i.e., working 26 days 
followed by 4 days off) is contrary to the intent of the regulation, 
which was designed to mitigate the effects of fatigue for maintenance 
personnel. Fatigue degrades a person's ability to work effectively. 
Some causes of fatigue are sleep deprivation and time spent on duty. 
See Advisory Circular AC 120-72, Maintenance Resource Management 
Training, (Sept. 28, 2000). Given that Sec.  121.377 places no limit on 
the amount of time maintenance personnel may work, it may be possible 
for these personnel to work consecutive 8, 12, or 16-hour shifts. This 
type of schedule, combined with delaying rest periods until the end of 
the month, may result in reduced reaction time, impaired short-term 
memory, decreased vigilance, reduced motivation, increased 
irritability, and an increase in the number of errors made for 
maintenance personnel. In light of these factors, the allowance for 
some flexibility in scheduling the 24-hour consecutive rest period 
required by Sec.  121.377 is not without limitation. Thus, a schedule 
that delays providing the requisite rest under Sec.  121.377 until the 
end of the calendar month, such that the exception in Sec.  121.377 
becomes the normal practice, would not be considered compliant with the 
rest requirements of 14 CFR 121.377. The text of the May 18, 2010 
interpretation is as follows:

Alexandra M. McHugh,
Assistant Counsel.

United Technologies Corporation, Pratt & Whitney Legal Services, 400 
Main Street, M/S 132-12, East Hartford, CT 06108

    Dear Ms. McHugh: This is in response to Pratt & Whitney's letter of 
May 19, 2008, concerning the application of Sec.  121.377 to 
maintenance personnel at Pratt's repair facility certified under Part 
145 of the Federal Aviation Regulations. Based on the several factual 
scenarios contained in the letter and subsequent conversations between 
Pratt and my office, I have organized this response into three general 
issues. The first deals with whether Pratt can view as non-duty time 
the time an employee spends completing non-maintenance work or tasks 
while being compensated by Pratt, even while away from Pratt's 
facility. The second explores the extent to which Pratt may view as 
non-duty time the time an employee spends at other employment while off 
duty from Pratt, even if it is aviation related work. The last issue 
concerns the limit of scheduling flexibility provided by the 
regulation. I believe you will be able to apply the answers to these 
three questions to all of the specific scenarios you posited in your 
    For repair stations certificated under Part 145 that perform 
maintenance work for air carriers operating under Part 121, Sec.  
121.377 establishes a maximum duty period for maintenance personnel 
working for that repair station. That section reads:
    Within the United States, each certificate holder (or person 
performing maintenance or preventive maintenance functions for it) 
shall relieve each person performing maintenance or preventive 
maintenance from duty for a period of at least 24 consecutive hours 
during any seven consecutive days, or the equivalent thereof within any 
one calendar month.

14 CFR Sec.  121.377. Thus, generally, maintenance personnel must be 
allowed 24 consecutive hours of rest during any seven consecutive days. 
In the context of discussing Maintenance Resource Management concepts, 
the FAA has stated in Advisory Circular (AC) 120-72 (September 28, 
2000) that addressing fatigue-related errors ensures the safety of 
flight in passenger carrying operations. Fatigue often leads to 
decreased vigilance and impaired short term memory, resulting in a 
likely increase in human error. A common known cause of fatigue is 
``time on duty.'' AC 120-72, para. 9(h)(2)(f). Therefore, the general 
rule in Sec.  121.377 is intended to reduce the likelihood of fatigue-
related maintenance errors in air carrier operations.

    Section 121.377 requires that a person performing maintenance or 
preventative maintenance be relieved from ``duty'' for, generally, one 
day out of every seven. One question, then, is what is considered 
``duty.'' In other contexts, the FAA has defined duty as ``actual work 
for the [employer] or the present responsibility for such should the 
occasion arise.'' See Legal Interpretation 1993-31 (Dec. 13, 1993). 
Prior interpretations have concluded that performing a mix of tasks, 
some of which do not involve work for a Part 121 air carrier or even 
non-aviation related tasks, but are tasks assigned to the employee by 
the employer, still fall within the category of ``duty'' for purposes 
of applying Sec.  121.377. Legal Interpretation to Ron Webb from Donald 
P. Byrne, Assistant Chief Counsel, Regulations (June 21, 1991); cf. 
Legal Interpretation to Jim Mayors from Rebecca B. MacPherson, 
Assistant Chief Counsel for Regulations (Mar. 2, 2009) (noting that the 
time a pilot participated in a 2-hour company meeting that was not 
related to a company assignment of flight time, must still be 
calculated as part of his duty day because he was not free from all 
work obligations during that time); Legal Interpretation to Jay Wells 
from Rebecca MacPherson, Assistant Chief Counsel, Regulations Division 
(October 29, 2007); Legal Interpretation to James W. Johnson from 
Donald P. Byrne, Assistant Chief Counsel for Regulations (May 9, 2003).
    Therefore, for purposes of applying Sec.  121.377, any time for 
which an employee ``has actual work for the employer, or the present 
responsibility for such work, should it arise,'' constitutes ``duty'' 
time. Accordingly, the time an employee is engaged in maintenance 
tasks, attending a bargaining unit meeting, attending a training 
session, doing work related to Pratt's educational benefit, traveling 
from the point on Pratt's campus where the employee ``clocked in'' to 
the employee's work area, or working for another unit within Pratt's 

[[Page 21272]]

umbrella, constitutes time that must be included in the calculation of 
duty time to determine the rest required under Sec.  121.377, whether 
or not that unit itself must adhere to the requirements of Sec.  
121.377. An employee using accrued vacation or credit time is not ``on 
duty'' even though the employee may receive compensation for that time. 
Nevertheless, the regulation aims to require repair stations to give 
its maintenance personnel at least one day off every week without 
requiring that employee to use accrued vacation time to be free from 
any responsibility for work.
    Once Pratt relieves the employee from duty, the regulation does not 
require Pratt to monitor the employee's activities. The scenario where 
an employee uses the time off from Pratt to work at another maintenance 
facility does not implicate Pratt's compliance with Sec.  121.377. 
Unlike the regulations governing crewmember duty time, Sec.  121.377 
does not contain a limit on an employee's total accumulated working 
hours within a specified period of time. The FAA does not recommend 
this practice, however, for the reasons discussed in AC 120-72 related 
to fatigue. Thus, an employee relieved from duty by Pratt may perform 
other aviation related maintenance, even for other facilities which 
themselves are bound by Sec.  121.377, provided the employee is 
provided the requisite time off by each facility for which the employee 
works. Pratt must use caution, however, not to create the appearance of 
requiring an employee to work during off hours for another facility 
that is just a corporate sister to the Pratt facility.
    You also raise the question of whether a facility can schedule 
employees to work more than six consecutive days, thereby grouping 
required days off, and still remain in compliance with Sec.  121.377. 
The regulatory standard requires 24 consecutive hours off duty during 
any seven consecutive days but also contains some flexibility in the 
phrase ``or the equivalent thereof within any one calendar month.'' The 
FAA intended that the regulation allow employees to work in excess of 
six consecutive days in the event of a national emergency or unusual 
occurrence in the air carrier industry. See Legal Interpretation 1987-
15 (June 14, 1987). The regulatory flexibility found in Sec.  121.377 
allows maintenance personnel to work a schedule that maintains the 
``equivalent'' to one day off every week even though that schedule 
might provide for more than six consecutive days of work.
    The equivalent standard, however, does have limits. The tenants of 
statutory and regulatory interpretation suggest that the specific 
standard of one day off every week cannot be rendered completely 
inoperative by the more general equivalent standard. A previous 
interpretation allowed that a work schedule that provides for personnel 
to have a group of 4 days off followed by up to 24 days of work, or 
vice versa, would still meet the standard of being ``equivalent'' to 
one day off in every seven within a month. Legal Interpretation to Ron 
Webb from Donald P. Byrne, Assistant Chief Counsel, Regulations (June 
21, 1991). That interpretation, however, was issued prior to the 
findings relating fatigue to maintenance related errors in the air 
carrier industry discussed in AC 120-72. Webster's dictionary defines 
``equivalent'' as having logical equivalence, or corresponding or 
virtually identical in effect or function. Today, we would not view as 
compliant a schedule that provides over the course of eight weeks for 
four days off followed by 48 straight days of duty followed by four 
more days off. Such a work schedule that generally provides for an 
average of one day off over several weeks cannot be said to be 
``equivalent'' to the more specific standard requiring one day off out 
of every seven days.
    Lastly, you correctly note that the regulation does not address the 
length of the work day, only the length of the required time off work. 
The legal interpretation from Mr. Byrne to Mr. Webb also makes clear 
that the general equivalency provision in Sec.  121.377 does not apply 
to the specific requirement to give 24 consecutive hours of time off. 
Time off may not be provided in smaller increments over several days 
even though the total time off over any seven day period may equal or 
exceed 24 hours.
    We appreciate your patience and trust that the above responds to 
your concerns. If you need further assistance, please contact my staff 
at (202) 267-3073. This response was prepared by Anne Bechdolt, 
Attorney in the Operations Law Branch of the Regulations Division of 
the Office of the Chief Counsel, and coordinated with the Aircraft 
Maintenance and Air Transportation divisions of Flight Standards 

Rebecca B. MacPherson,
Assistant Chief Counsel, Regulations Division

[FR Doc. 2011-9236 Filed 4-14-11; 8:45 am]