[Federal Register Volume 80, Number 19 (Thursday, January 29, 2015)]
[Rules and Regulations]
[Pages 4761-4762]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-01205]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 25

[Docket No. FAA-2013-0142; Amdt. No. 25-141]
RIN 2120-AK12


Harmonization of Airworthiness Standards--Gust and Maneuver Load 
Requirements; Correction

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; correction.

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SUMMARY: The FAA is correcting the final rule, ``Harmonization of 
Airworthiness Standards--Gust and Maneuver Load Requirements'' (79 FR 
73462), published December 11, 2014. In the rule, the FAA amended 
certain airworthiness regulations for transport category airplanes to 
eliminate regulatory differences between the airworthiness standards of 
the FAA and European Aviation Safety Agency (EASA). It does not add new 
requirements beyond what manufacturers currently meet for EASA 
certification and does not affect current industry design practices. 
This final rule revises the pitch maneuver design loads criteria; 
revises the gust and turbulence design loads criteria; revises the 
application of gust loads to engine mounts, high lift devices, and 
other control surfaces; adds a ``round-the-clock'' discrete gust 
criterion and a multi-axis discrete gust criterion for airplanes 
equipped with wing-mounted engines; revises the engine torque loads 
criteria; adds an engine failure dynamic load condition; revises the 
ground gust design loads criteria; revises the criteria used to 
establish the rough air design speed; and requires the establishment of 
a rough air Mach number. This document corrects errors in the rule by 
ensuring that certain letters in the included equations have the right 
formatting and therefore the correct meaning.

DATES: This correction is effective February 9, 2015.

FOR FURTHER INFORMATION CONTACT: For technical questions concerning 
this action, contact Todd Martin, Airframe and Cabin Safety Branch, 
ANM-115, Transport Airplane Directorate, Aircraft Certification 
Service, Federal Aviation Administration, 1601 Lind Avenue SW., Renton, 
WA 98057-3356; telephone (425) 227-1178; facsimile (425) 227-1232; 
email [email protected].
    For legal questions concerning this action, contact Sean Howe, 
Office of the Regional Counsel, ANM-7, Federal Aviation Administration, 
1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone (425) 
227-2591; facsimile (425) 227-1007; email [email protected].

SUPPLEMENTARY INFORMATION:

Background

    On December 11, 2014, the FAA published the final rule entitled, 
``Harmonization of Airworthiness Standards--Gust and Maneuver Load 
Requirements'' (79 FR 73462).

[[Page 4762]]

    In the rule, the FAA amended certain airworthiness regulations for 
transport category airplanes to eliminate regulatory differences 
between the airworthiness standards of the FAA and European Aviation 
Safety Agency (EASA). It does not add new requirements beyond what 
manufacturers currently meet for EASA certification and does not affect 
current industry design practices. This final rule revises the pitch 
maneuver design loads criteria; revises the gust and turbulence design 
loads criteria; revises the application of gust loads to engine mounts, 
high lift devices, and other control surfaces; adds a ``round-the-
clock'' discrete gust criterion and a multi-axis discrete gust 
criterion for airplanes equipped with wing-mounted engines; revises the 
engine torque loads criteria; adds an engine failure dynamic load 
condition; revises the ground gust design loads criteria; revises the 
criteria used to establish the rough air design speed; and requires the 
establishment of a rough air Mach number.
    This document corrects three errors in the Greek letters and 
subscripts contained in various equations in the regulatory text. In 
one case, the ``U'' in the equation is changed from subscript to 
regular, uppercase text. In another case, instead of ``PL = 
PL-1g  U[sigma]AA'', the 
equation should be ``PL = PL-1g  
U[sigma]AA''. In two cases, the three Greek letters 
``[rho][egr][phis]'' after sigma ``[sigma]'' in the subscript of ``U'' 
are changed to ``ref''. In these cases, 
``U[sigma][rho][egr][phis]'' should be 
``U[sigma]ref''.
    This correction also corrects the statement in the rule's preamble 
that the FAA received 33 comments to the Advisory Circulars, rather 
than none.

Corrections

    In FR Doc. 2014-28938, beginning on page 73464, in the Federal 
Register of December 11, 2014, make the following corrections:
    1. On Page 73464, second column, under the heading ``C. Advisory 
Material'', the sentence, ``The FAA did not receive any comments on the 
proposed ACs'' is corrected to read ``The FAA received 33 comments on 
the proposed ACs. These comments did not have an impact on the 
regulatory requirements''.
    2. On page 73467, second column, line 11, the equation 
``PL = PL-1g  
U[sigma]AA'' is corrected to read ``PL 
= PL-1g  U[sigma]AA''.
    3. On page 73467, second column, fifth line from the bottom, the 
equation ``U[sigma] = 
U[sigma][rho][egr][phis]Fg'' is corrected to read 
``U[sigma] = U[sigma]ref Fg''.
    4. On page 73467, second column, third line from the bottom, the 
text ``U[sigma][rho][egr][phis]'' is corrected to read 
``U[sigma]ref''.

    Issued in Washington, DC, on January 16, 2015.
Lirio Liu,
Director, Office of Rulemaking.
[FR Doc. 2015-01205 Filed 1-28-15; 8:45 am]
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