2012-25606. Special Conditions: Airbus Model A318, A319, A320, and A321 Series Airplanes; Design Roll Maneuver Conditions

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final special conditions; request for comments.

SUMMARY:

These special conditions are issued for the Airbus Model A318, A319, and A320 series airplanes with modification 160500 and Model A321 series airplanes with modification 160023 (Sharklet). These airplanes will have novel or unusual design features when compared to the state of technology envisioned in the airworthiness standards for transport category airplanes. These design features include electronic flight controls that affect maneuvering. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.

DATES:

The effective date of these special conditions is October 11, 2012. We must receive your comments by December 3, 2012.

ADDRESSES:

Send comments identified by docket number FAA-2012-1120 using any of the following methods:

• Federal eRegulations 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 (DOT), 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 8 a.m. and 5 p.m., Monday through Friday, except federal holidays.
• Fax: Fax comments to Docket Operations at 202-493-2251.

Privacy: The FAA will post all comments it receives, without change, to http://www.regulations.gov/​,, including any personal information the commenter provides. Using the search function of the docket Web site, anyone can find and read the electronic form of all comments received into any FAA docket, including the name of the individual sending the comment (or signing the comment for an association, business, labor union, etc.). DOT's complete Privacy Act Statement can be found in the Federal Register published on April 11, 2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov/​.

Docket: Background documents or comments received may be read at http://www.regulations.gov/​ at any time. Follow the online instructions for accessing the docket or go to the 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:

Todd Martin, FAA, Airframe/Cabin Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone [phone]; facsimile 425-227-1232.

SUPPLEMENTARY INFORMATION:

The FAA has determined that notice of, and opportunity for prior public comment on, these special conditions are impracticable because these procedures would significantly delay issuance of the design approval and thus delivery of the affected aircraft. In addition, the substance of these special conditions has been subject to the public comment process in several prior instances with no substantive comments received. The FAA therefore finds that good cause exists for making these special conditions effective upon issuance.

Comments Invited

We invite interested people to take part in this rulemaking by sending written comments, data, or views. The most helpful comments reference a specific portion of the special conditions, explain the reason for any recommended change, and include supporting data.

We will consider all comments we receive by the closing date for comments. We may change these special conditions based on the comments we receive.

Background

On April 8, 2010, Airbus applied for a change to Type Certificate No. A28NM to include modification 160500 on Airbus Model A318, A319, and A320 series airplanes and modification 160023 on Model A321 series airplanes for the installation of a “Sharklet,” a large wingtip device. The Model A318, A319, A320, and A321 series airplanes are short to medium-range, twin turbofan, transport category airplanes with a maximum seating capacity of 136 to 220 passengers, a maximum takeoff weight of 130,071 to 205,027 pounds, and a maximum operating altitude of 39,800 feet.

FAA issued special conditions 25-ANM-23, effective December 15, 1988, originally applicable to Airbus Model A320 series airplanes and later to the Model A318, A319, and A321 series airplanes. Those special conditions included requirements for design roll maneuver conditions. The FAA has determined that new special conditions are needed for the Airbus Model A318, A319, and A320 series airplanes with modification 160500 and Model A321 series airplanes with modification 160023 (Sharklet) and later derivatives because the existing special conditions have evolved over the years and need to be updated for this derivative program.

Type Certification Basis

Under the provisions of Title 14, Code of Federal Regulation (14 CFR) 21.101, Airbus must show that the Model A318, A319, A320, and A321 series airplanes, as changed, continue to meet the applicable provisions of the regulations incorporated by reference in Type Certificate No. A28NM or the applicable regulations in effect on the date of application for the change. The regulations incorporated by reference in the type certificate are commonly referred to as the “original type certification basis.” The regulations incorporated by reference in Type Certificate No. A28NM are 14 CFR part 25, as amended by Amendments 25-1 through 25-56, and special conditions 25-ANM-23. In addition, the certification basis includes certain special conditions, exemptions, or later amended sections of the applicable part that are not relevant to these special conditions.

If the Administrator finds that the applicable airworthiness regulations (i.e., 14 CFR part 25) do not contain adequate or appropriate safety standards for the Model A318, A319, A320, and A321 series airplanes because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16.

Special conditions are initially applicable to the model for which they are issued. Should the type certificate for that model be amended later to include any other model that incorporates the same novel or unusual design feature, or should any other model already included on the same type certificate be modified to incorporate the same novel or unusual design feature, the special conditions would also apply to the other model.

In addition to the applicable airworthiness regulations and special conditions, the Model A318, A319, A320, and A321 series airplanes must comply with the fuel vent and exhaust emission requirements of 14 CFR part 34 and the noise certification requirements of 14 CFR part 36.

The FAA issues special conditions, as defined in 14 CFR 11.19, in accordance with § 11.38, and they become part of the type-certification basis under § 21.101.

Novel or Unusual Design Features

The Airbus Model A318, A319, and A320 series airplanes with modification 160500 and Model A321 series airplanes with modification 160023 (Sharklet) will incorporate the following novel or unusual design feature: Electronic flight controls that affect maneuvering.

The current design roll maneuver requirement in 14 CFR part 25 is inadequate for addressing an aircraft with electronic flight controls that affect maneuvering. Special conditions are needed to adjust the current roll maneuver requirement in § 25.349(a) to take into account the effects of an electronic flight control system.

Discussion

Current part 25 airworthiness regulations account for control laws for which aileron deflection is proportional to control stick deflection. They do not address any nonlinearities or other effects on aileron actuation that may be caused by electronic flight controls. Since this type of system may affect flight loads, and therefore the structural capability of the airplane, specific regulations are needed to address these effects.

These proposed special conditions differ from current requirements in that they require that the roll maneuver be performed by actuation of the cockpit roll control as opposed to the aileron itself. Also, the proposed special conditions require an additional load condition at V_A, in which the cockpit roll control is returned to neutral following the initial roll input.

Applicability

As discussed above, these special conditions are applicable to the Airbus Model A318, A319, A320 series airplanes with modification 160500 and Model A321 series airplanes with modification 160023 (Sharklet). Should Airbus apply at a later date for a change to the type certificate to include another model incorporating the same novel or unusual design feature, the special conditions would apply to that model as well.

Conclusion

This action affects only certain novel or unusual design features on the model series of airplanes listed above. It is not a rule of general applicability.

The substance of these special conditions has been subjected to the notice and comment period in several prior instances and has been derived without substantive change from those previously issued. It is unlikely that prior public comment would result in a significant change from the substance contained herein. Therefore, because a delay would significantly affect the certification of the airplane, which is imminent, the FAA has determined that prior public notice and comment are unnecessary and impracticable, and good cause exists for adopting these special conditions upon issuance. The FAA is requesting comments to allow interested persons to submit views that may not have been submitted in response to the prior opportunities for comment described above.

List of Subjects in 14 CFR Part 25

• Aircraft
• Aviation safety
• Reporting and recordkeeping requirements

The authority citation for these special conditions is as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Special Conditions

Accordingly, pursuant to the authority delegated to me by the Administrator, the following special conditions are issued as part of the type certification basis for Airbus Model A318, A319, and A320 series airplanes with modification 160500 and Model A321 with modification 160023 (Sharklet) series airplanes.

Design Roll Maneuver Conditions. The following conditions, speeds, and cockpit roll control motions (except as the motions may be limited by pilot effort) must be considered in combination with an airplane load factor of zero and of two-thirds of the positive maneuvering factor used in design. In determining the resulting control surface deflections, the torsional flexibility of the wing must be considered in accordance with § 25.301(b):

1. Conditions corresponding to steady rolling velocities must be investigated. In addition, conditions corresponding to maximum angular acceleration must be investigated for airplanes with engines or other weight concentrations outboard of the fuselage. For the angular acceleration conditions, zero rolling velocity may be assumed in the absence of a rational time history investigation of the maneuver.

2. At V_A, sudden movement of the cockpit roll control up to the limit is assumed. The position of the cockpit roll control must be maintained until a steady roll rate is achieved and then must be returned suddenly to the neutral position.

3. At V_C, the cockpit roll control must be moved suddenly and maintained so as to achieve a roll rate not less than that obtained in paragraph 2.

4. At V_D, the cockpit roll control must be moved suddenly and maintained so as to achieve a roll rate not less than one third of that obtained in paragraph 2.

Issued in Renton, Washington, on October 11, 2012.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.