AD 2017-22-11

This AD is effective December 20, 2017.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of December 20, 2017.

For service information identified in this final rule, contact Bombardier, Inc., 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; telephone: 514-855-5000; fax: 514-855-7401; email: thd.crj@aero.bombardier.com; Internet: http://www.bombardier.com. You may view this referenced service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0528.

Assata Dessaline, Aerospace Engineer, Avionics and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone: 516-228-7301; fax: 516-794-5531.

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain Bombardier, Inc., Model CL-600-2B16 (CL-604 Variant) airplanes. The NPRM published in the Federal Register on June 5, 2017 (82 FR 25746) (“the NPRM”). The NPRM was prompted by reports of in-service incidents regarding the loss of all air data system information provided to the flightcrew. The NPRM proposed to require revising the AFM to provide “Unreliable Airspeed” procedures to the flightcrew to stabilize the airplane's airspeed and attitude for continued safe flight and landing. We are issuing this AD to provide the flightcrew with procedures for “Unreliable Airspeed” that stabilize the airplane's airspeed and attitude for continued safe flight and landing.

Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF-2017-01, dated January 6, 2017 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for certain Bombardier, Inc., Model CL-600-2B16 (CL-604 Variant) airplanes. The MCAI states:

A number of in-service incidents have been reported on CL-600-2C10 aeroplanes regarding a loss of all air data information provided to the crew. The air data information was recovered as the aeroplane descended to lower altitudes. An investigation determined that the root cause in both events was high altitude icing (ice crystal contamination). If not recognized and addressed, this condition may affect continued safe flight and landing.

Due to similarities in the air data systems, similar events could happen on Bombardier Inc. CL-600-2B16 aeroplanes.

This [Canadian] AD mandates the incorporation of Aircraft Flight Manual (AFM) procedures to guide the crew to stabilize the aeroplanes airspeed and attitude for continued safe flight and landing.

You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0528.

We gave the public the opportunity to participate in developing this AD. We considered the comment received.

The commenter, Marjolaine Bourget, stated that the “unreliable airspeed” procedures, while provided in the AFM revisions identified in the proposed requirements, were actually introduced in the previous revision of the identified AFMs.

From this statement, we infer that the commenter was requesting that we add a statement that the “unreliable airspeed” procedures were introduced in the previous revision of the identified AFMs. The commenter provided no justification for this request. We acknowledge that the “unreliable airspeed” procedures were introduced in an earlier revision of the identified AFMs. We have revised this AD by adding new paragraph (h) to this AD that provides credit to operators for previously completing the actions required by paragraph (g) of this AD if they used the applicable previous AFM revision.

We reviewed the relevant data, considered the comment received, and determined that air safety and the public interest require adopting this AD as proposed, except for minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

Bombardier, Inc., has issued Unreliable Airspeed, of Section 03-15, Instruments System, of Chapter 3, Emergency Procedures, of the following AFMs:

• Bombardier Challenger 604 AFM, Publication No. CH 604 AFM, Revision 103, dated November 28, 2016.

• Bombardier Challenger 605 AFM, Publication No. CH 605 AFM, Revision 41, dated November 28, 2016.

• Bombardier Challenger 650 AFM, Publication No. CH 650 AFM, Revision 6, dated November 28, 2016.

This service information provides revisions to the Emergency Procedures section of the AFM to incorporate a procedure for “Unreliable Airspeed.” These documents are distinct since they apply to different airplane configurations. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

We estimate that this AD affects 128 airplanes of U.S. registry.

We also estimate that it takes about 1 work-hour per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Based on these figures, we estimate the cost of this AD on U.S. operators to be $10,880, or $85 per product.

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. “Subtitle VII: Aviation Programs,” describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in “Subtitle VII, Part A, Subpart III, Section 44701: General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

We determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):