2015-01205. Harmonization of Airworthiness Standards-Gust and Maneuver Load Requirements; Correction

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; correction.

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 [phone]; facsimile [phone]; email [e-mail].

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 [phone]; facsimile [phone]; email [e-mail].

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).

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 “P_L = P_L-1g ±_Uσ Ā”, the equation should be “P_L = P_L-1g ± U_σ Ā”. In two cases, the three Greek letters “ρεφ” after sigma “σ” in the subscript of “U” are changed to “ref”. In these cases, “U_σρεφ” should be “U_σref”.

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 “P_L = P_L-1g ±_Uσ Ā” is corrected to read “P_L = P_L-1g ± U_σ Ā”.

3. On page 73467, second column, fifth line from the bottom, the equation “U_σ = U_σρεφ F_g” is corrected to read “U_σ = U_σref F_g”.

4. On page 73467, second column, third line from the bottom, the text “U_σρεφ” is corrected to read “U_σref”.

Issued in Washington, DC, on January 16, 2015.

Lirio Liu,

Director, Office of Rulemaking.