2017-10282. Airworthiness Directives; Airbus Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for all Airbus Model A330-223F, -223, -321, -322, and -323 airplanes. This AD was prompted by fatigue load analysis that determined the need for reduced inspection intervals and updated torque values of the bolts. This AD requires repetitive torque checks of the forward engine mount bolts, an inspection of the forward mount assembly, and replacement of the bolts or repair of the forward mount assembly as necessary. We are issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective June 29, 2017.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of June 29, 2017.

ADDRESSES:

For service information identified in this final rule, contact Airbus SAS, Airworthiness Office—EAL, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone [phone]; fax [phone]; email [e-mail]; Internet http://www.airbus.com. You may view this referenced service information at the FAA, Transport Airplane Directorate, 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-2016-8849.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-8849; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (telephone [phone]) is Docket Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Vladimir Ulyanov, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356; telephone: [phone]; fax: [phone].

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Airbus Model A330-223F, -223, -321, -322, and -323 airplanes. The NPRM published in the Federal Register on August 30, 2016 (81 FR 59535). The NPRM was prompted by fatigue load analysis that determined the need for reduced inspection intervals (for torque checks required by AD 2013-14-04, Amendment 39-17509 (78 FR 68352, November 14, 2013) (“AD 2013-14-04”)) and updated torque values of the bolts. The NPRM proposed to require repetitive torque checks to determine if there are any loose or broken forward engine mount bolts, and, if necessary, replacement of all four forward engine mount bolts and associated nuts, inspection of the forward mount assembly, and repair. We are issuing this AD to detect and correct loose and broken bolts, which could lead to engine detachment in flight and damage to the airplane.

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2015-0214, dated October 19, 2015 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for all Airbus Model A330-223F, -223, -321, -322, and -323 airplanes. The MCAI states:

The forward mount engine pylon bolts, Part Number (P/N) 51U615, fitted on Airbus A330 aeroplanes with Pratt & Whitney (PW) PW4000 engines, are made from MP159 material. Analysis made by PW identified that MP159 material pylon bolts do not meet the full life cycle torque check interval requirement, in a bolt-out condition. Consequently, PW issued Alert Service Bulletin (ASB) PW4G-100-A71-32, and the U.S. Federal Aviation Administration (FAA), as Engine Certification Authority, issued FAA AD 2006-16-05 [Amendment 39-14705 (71 FR 44185, August 4, 2006) (“AD 2006-16-05”)] to require repetitive torque checks of MP159 material forward mount pylon bolts fitted on certain PW4000 series engines.

However, the engine mount system is considered to be part of aeroplane certification rather than the engine certification. Following further fatigue load analysis by Airbus of the A330 engine mount system, it was determined that the torque check interval for MP159 material forward mount pylon bolts, as required by FAA AD 2006-16-05 (2,700 flight cycles (FC)), provided an insufficient level of safety for Airbus A330 aeroplanes.

This condition, if not detected and corrected, could ultimately lead to detachment of the engine from the aeroplane, possibly resulting in damage to the aeroplane and/or injury to persons on the ground.

Consequently, EASA issued AD 2012-0094 [which corresponds to FAA AD 2013-14-04] to require accomplishment of repetitive torque checks of the forward mount pylon bolts installed on affected A330 aeroplanes and, depending on findings, replacement of all four bolts and associated nuts, in accordance with PW ASB PW4G-100-A71-32 Revision 01 and Airbus Service Bulletin (SB) A330-71-3028.

Since that AD was issued, it has been concluded that a new torque value must be applied.

Consequently, Airbus issued SB A330-71-3028 Revision 02 and PW issued ASB PW4G-100-A71-32 Revision 02 to update the torque value. Additional forward mount inspections are also provided in case of one or more forward engine mount bolts is found loose, broken or missing.

For the reasons described above, this [EASA] AD retains the requirements of EASA AD 2012-0094, which is superseded, introduces a new torque value, and requires additional inspections and, depending on findings, corrective action(s).

Corrective actions include repetitive torque checks to determine if there are any loose or broken forward engine mount bolts on both engines, and, if necessary, replacement of all four forward engine mount bolts and associated nuts, inspection of the forward mount assembly, and repair. 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-2016-8849.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment.

Request To Correct Typographical Error

American Airlines (AA) requested that we correct the reference to the FAA AD in paragraph (g)(1) of the proposed AD, which incorrectly identified AD 2013-13-05. The correct AD number for this terminating action is 2013-14-04.

We agree and have revised paragraph (g)(1) of this AD accordingly.

Request To Clarify Compliance Time

AA requested that we clarify the compliance time for airplanes with an average flight time (AFT) of more than 132 minutes for the second cycle interval (1,851-2,700 flight cycles). AA proposed that we revise the second row of table 1 to paragraph (g) of the proposed AD by referring to the specified compliance times since accomplishing actions in AD 2013-14-04.

We agree that clarification is necessary. The compliance times for the initial and repetitive torque checks required by AD 2013-14-04 are identified in table 1 to paragraph (g)(1) of this AD (table 1 to paragraph (g) of the proposed AD). The compliance times include specified flight cycles since the last torque check specified in Pratt & Whitney Alert Service Bulletin PW4G-100-A71-32, which operators might have accomplished to comply with AD 2013-14-04. Paragraph (g)(1) of this AD requires that the next torque check be done in accordance with Airbus Service Bulletin A330-71-3028, Revision 02, dated August 31, 2015 (“A330-71-3028, R02”). Accomplishment of the torque check required by paragraph (g)(1) of this AD terminates the requirements of AD 2013-14-04. We have not changed this AD regarding this issue.

Request To Clarify Terminating Action

Paragraph (h) of the proposed AD stated that accomplishment of the actions specified by paragraph (g) of the proposed AD “constitutes compliance with” the requirements specified in paragraph (g) of AD 2006-16-05. AA requested that we revise paragraph (h) of the proposed AD to specifically state that the new AD would also “terminate” the inspection specified in AD 2006-16-05.

We agree with the commenter. We have revised paragraph (h) of this AD to state that accomplishment of the actions required by paragraph (g) of this AD terminates the requirements of paragraph (g) of AD 2006-16-05.

Request To Allow Use of Higher Torque Values

AA requested that we revise paragraph (j) of the proposed AD to specifically allow early compliance with the AD upon its release and prior to the effective date of the AD, using Airbus Service Bulletin A330-71-3028, R02. AA stated that this would allow operators to immediately begin using the higher torque values specified in Airbus Service Bulletin A330-71-3028, R02. AA stated that as written, the AD would not allow operators to immediately use the higher torque values specified in Airbus Service Bulletin A330-71-3028, R02, because AD 2013-14-04 specifies the use of Airbus Service Bulletin A330-71-3028, Revision 01, dated February 12, 2012, which contains lower torque values. AA stated that this would preclude the need for a request for an alternative method of compliance (AMOC) against AD 2013-14-04 to allow the use of the higher torque values, and that this change would streamline the compliance revision process.

We acknowledge the request and agree that clarification is necessary. Because AD 2013-14-04 requires using Airbus Service Bulletin A330-71-3028, Revision 01, dated February 12, 2012, operators need approval to use Airbus Service Bulletin A330-71-3028, R02, as an AMOC for the requirements of AD 2013-14-04. We have issued global AMOC ANM-116-17-243, dated April 4, 2017, approving the use of Airbus Service Bulletin A330-71-3028, R02, for compliance with the requirements of AD 2013-14-04. Therefore, no changes to this AD are necessary regarding this issue.

Request To Limit Requirements for Certain Approvals

Delta Air Lines (Delta) requested that we revise the statement in paragraph (g)(2) of the proposed AD to remove the requirement to obtain FAA, EASA, or Airbus Design Organization Approval (DOA) approval for any instance where Airbus Service Bulletin A330-71-3028, R02, specifies contacting Airbus. Delta requested that we instead require these approvals only for damage that exceeds the allowable limits in the airplane maintenance manual (AMM); component maintenance manual (CMM); or cleaning, instruction and repair (CIR) manual. Delta stated that Airbus Service Bulletin A330-71-3028, R02, specifies contacting Airbus any time a bolt is found out of tolerance regardless whether any damage is found. As such, this would effectively require FAA, EASA, or Airbus DOA approval any time a bolt is found with a torque out of limits, even if there is no damage to the forward mount assembly, or if the damage is within the AMM, CMM, or CIR allowable limits. Delta agreed with the required approvals, but only when there is damage that exceeds those limits. Delta stated that this change would limit the number of AMOC requests, and reduce airplane out-of-service times while maintaining the acceptable level of safety.

We disagree with the commenter's request to change the corrective action requirement in paragraph (g)(2) of this AD. The requirements of this AD correspond with those specified in the MCAI. The MCAI refers to Airbus Service Bulletin A330-71-3028, R02, which specifies that when any bolt is found with a torque out of limits, corrective actions must be done. We have determined that these actions are necessary to address the identified unsafe condition. However, under the provisions of paragraph (k)(1) of this AD, we will consider requests for approval of alternative corrective actions if sufficient data are submitted to substantiate that the alternative actions would provide an acceptable level of safety. We have not changed this AD regarding this issue.

Request To Allow Replacement Instead of Repair

Delta stated that paragraph (g)(2) of the proposed AD, which applies to the airplane (not the engine mount), would require repair before further flight. Delta interpreted this to mean the proposed AD would require repair of the forward engine mount before the airplane could return to flight. Delta requested that we revise the proposed AD to include a statement that explicitly allows replacement of damaged engine mounts, allowing the airplane to return to service as quickly as possible.

We partially agree with the commenter's request. We agree that replacement of an affected forward engine mount might be allowed as a corrective action and that a different compliance time may be acceptable. We have revised paragraph (g)(2) of this AD by replacing the proposed requirement to repair before further flight with the requirement to contact the FAA, EASA, or Airbus's EASA DOA before further flight to obtain applicable corrective action instructions approved by the FAA, EASA, or Airbus's EASA DOA, and to do applicable corrective actions within the compliance time specified in those instructions.

Conclusion

We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting this AD with the changes described previously and minor editorial changes. We have determined that these 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.

We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

Airbus has issued Service Bulletin A330-71-3028, Revision 02, dated August 31, 2015. The service information describes procedures for repetitive torque checks for loose or broken forward engine mount bolts on both engines, replacement of all four forward engine mount bolts and associated nuts, and inspection of the forward mount assembly. 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.

Costs of Compliance

We estimate that this AD affects 41 airplanes of U.S. registry.

We also estimate that it would take about 3 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Required parts would cost about $6,747 per product. Based on these figures, we estimate the cost of this AD on U.S. operators to be $287,082, or $7,002 per product.

In addition, we estimate that any necessary follow-on actions would take about 1 work-hour and require parts costing $6,747, for a cost of $6,832 per product. We have no way of determining the number of aircraft that might need these actions.

Authority for This Rulemaking

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.

Regulatory Findings

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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

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

PART 39—AIRWORTHINESS DIRECTIVES

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

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

§ 39.13

[Amended]

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

2017-10-18 Airbus: Amendment 39-18892; Docket No. FAA-2016-8849; Directorate Identifier 2015-NM-174-AD.

(a) Effective Date

This AD is effective June 29, 2017.

(b) Affected ADs

This AD affects AD 2006-16-05, Amendment 39-14705 (71 FR 44185, August 4, 2006) (“AD 2006-16-05”); and AD 2013-14-04, Amendment 39-17509 (78 FR 68352, November 14, 2013) (“AD 2013-14-04”).

(c) Applicability

This AD applies to Airbus Model A330-223F, -223, -321, -322, and -323 airplanes, certificated in any category, all manufacturer serial numbers.

(d) Subject

Air Transport Association (ATA) of America Code 71, Powerplant.

(e) Reason

This AD was prompted by fatigue load analysis that determined the need for certain reduced inspection intervals and updated torque values of the forward engine mount pylon bolts. We are issuing this AD to detect and correct loose or broken bolts, which could lead to engine detachment in flight and damage to the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Torque Check, Replacement, and Terminating Action for AD 2013-14-04

(1) At the applicable compliance time specified in table 1 to paragraph (g)(1) of this AD, do a torque check to determine if there are any loose or broken forward engine mount bolts (4 positions/engine) on both engines, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A330-71-3028, Revision 02, dated August 31, 2015. Repeat the torque check at the applicable time intervals not to exceed the values specified in table 1 to paragraph (g)(1) of this AD. For the purposes of this AD, the average flight time (AFT) is defined as a computation of the number of flight hours divided by the number of flight cycles accumulated since the most recent torque check or since the airplane's first flight, as applicable. Accomplishment of the initial torque check required by this paragraph terminates the requirements of AD 2013-14-04.

Table 1 to Paragraph (g)(1) of This AD

Airplane models	Flight cycles accumulated as of December 19, 2013 (the effective date of AD 2013-14-04), since last torque check specified in Pratt & Whitney Alert Service Bulletin PW4G-100-A71-32 or since airplane's first flight, as applicable	Compliance time	Torque check interval (not to exceed)
Model A330-321, -322, and -323 airplanes with AFT more than 132 minutes; and Model A330-223 airplanes	0-1,850	Within 2,350 flight cycles since the last torque check as specified in Pratt & Whitney Alert Service Bulletin PW4G-100-A71-32, or since airplane's first flight, as applicable	2,350 flight cycles or 24,320 flight hours, whichever occurs first.
Model A330-321, -322, and -323 airplanes with AFT more than 132 minutes; and Model A330-223 airplanes	1,851-2,700	Within 500 flight cycles after December 19, 2013 (the effective date of AD 2013-14-04), without exceeding 2,700 flight cycles since last torque check as specified in Pratt & Whitney Alert Service Bulletin PW4G-100-A71-32, or since airplane's first flight, as applicable; or within 3 months after December 19, 2013; whichever occurs later	2,350 flight cycles or 24,320 flight hours, whichever occurs first.
Model A330-321, -322, and -323 airplanes with AFT 132 minutes or less; and Model A330-321, -322, and -323 airplanes on which the AFT is not calculated on a regular basis	0-1,450	Within 1,950 flight cycles since the last torque check performed as specified in Pratt & Whitney Alert Service Bulletin PW4G-100-A71-32, or since airplane's first flight, as applicable	1,950 flight cycles or 20,210 flight hours, whichever occurs first.
Model A330-321, -322, and -323 airplanes with AFT 132 minutes or less; and Model A330-321, -322, and -323 airplanes on which the AFT is not calculated on a regular basis	1,451-2,700	Within 500 flight cycles after December 19, 2013 (the effective date of AD 2013-14-04), without exceeding 2,700 flight cycles since last torque check performed as specified in Pratt & Whitney Alert Service Bulletin PW4-100-A71-32, or since airplane's first flight, as applicable; or within 3 months after December 19, 2013; whichever occurs later	1,950 flight cycles or 20,210 flight hours, whichever occurs first.
Model A330-223F airplanes	Any	Within 2,140 flight cycles or 6,600 flight hours, whichever occurs first since the last torque check performed as specified in Pratt & Whitney Alert Service Bulletin PW4G-100-A71-32, or since airplane's first flight, as applicable	2,140 flight cycles or 6,600 flight hours, whichever occurs first.

(2) If any loose or broken bolt is detected during the check required by paragraph (g)(1) of this AD, before further flight, do the actions specified by paragraphs (g)(2)(i) and (g)(2)(ii) of this AD, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A330-71-3028, Revision 02, dated August 31, 2015; except, where the service information specifies to contact the manufacturer for further corrective actions, before further flight contact the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or the European Aviation Safety Agency (EASA); or Airbus's EASA Design Organization Approval (DOA); to obtain applicable corrective action instructions approved by the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or EASA; or Airbus's EASA DOA; and accomplish the applicable corrective actions within the compliance time specified in those instructions.

(i) Replace all four forward engine mount bolts and associated nuts, on the engine where the loose or broken bolt was detected, with new bolts and nuts.

(ii) Do nondestructive inspections of the forward mount assembly for damage including cracks, dents, nicks, and scratches, and do all applicable corrective actions.

(3) Replacement of bolts and nuts as required by paragraph (g)(2)(i) of this AD is not terminating action for the repetitive torque checks required by paragraph (g)(1) of this AD.

(h) Terminating Action for Paragraph (g) of AD 2006-16-05

Accomplishment of the actions required by paragraph (g) of this AD terminates the requirements specified in paragraph (g) of AD 2006-16-05.

(i) Parts Installation Prohibition

As of December 19, 2013 (the effective date of AD 2013-14-04), no person may install, on any airplane, any forward mount pylon bolt made of INCO718 material and having Pratt & Whitney part number 54T670.

(j) Credit for Previous Actions

This paragraph provides credit for the actions required by paragraphs (g)(1) and (g)(2)(i) of this AD, if those actions were performed before the effective date of this AD using Airbus Service Bulletin A330-71-3028, dated December 16, 2011, or Airbus Service Bulletin A330-71-3028, Revision 01, dated February 20, 2012.

(k) Other FAA AD Provisions

The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the International Branch, send it to ATTN: Vladimir Ulyanov, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356; telephone: [phone]; fax: [phone]. Information may be emailed to: [e-mail]. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(2) Contacting the Manufacturer: As of the effective date of this AD, for any requirement in this AD to obtain corrective actions from a manufacturer, the action must be accomplished using a method approved by the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or EASA; or Airbus's EASA DOA. If approved by the DOA, the approval must include the DOA-authorized signature.

(3) Required for Compliance (RC): Except as required by paragraph (g)(2) of this AD: If any service information contains procedures or tests that are identified as RC, those procedures and tests must be done to comply with this AD; any procedures or tests that are not identified as RC are recommended. Those procedures and tests that are not identified as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the procedures and tests identified as RC can be done and the airplane can be put back in an airworthy condition. Any substitutions or changes to procedures or tests identified as RC require approval of an AMOC.

(l) Related Information

(1) Refer to Mandatory Continuing Airworthiness Information (MCAI) EASA AD 2015-0214, dated October 19, 2015, for related information. This MCAI may be found in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-8849.

(2) For more information about this AD, contact Vladimir Ulyanov, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356; telephone: [phone]; fax: [phone].

(3) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (m)(3) and (m)(4) of this AD.

(m) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise.

(i) Airbus Service Bulletin A330-71-3028, Revision 02, dated August 31, 2015.

(ii) Reserved.

(3) For service information identified in this AD, contact Airbus SAS, Airworthiness Office—EAL, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone [phone]; fax [phone]; email [e-mail]; Internet http://www.airbus.com.

(4) You may view this service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221.

(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued in Renton, Washington, on May 8, 2017.

Michael Kaszycki,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.