# AD 99-22-08: Pneumatic Augmentation Valve - Type: Airworthiness directive - Status: Current - Products: Boeing DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A) and 11 more - Effective: November 30, 1999 - Published: October 26, 1999, 64 FR 57551–57553 - Issued: October 15, 1999 - Issued as: Final rule - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Large airplane - Amendment: 39-11386 - Docket: 98-NM-382-AD - Registered aircraft: 113 may be affected, by airframe or engine model (OpenAirDocs) - Official PDF: https://openairdocs.org/files/sha256/36/a2/36a2cfe758c44be21d86eca8bb18feb80ebda329a214ec9dab2938d4ed66e607 (from https://www.govinfo.gov/content/pkg/FR-1999-10-26/pdf/99-27562.pdf) - Federal Register: https://www.federalregister.gov/documents/1999/10/26/99-27562/airworthiness-directives-mcdonnell-douglas-model-dc-9-dc-9-80-and-c-9-military-series-airplanes-and - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/2D885004F36EB51B86256A080069B043.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/99-22-08 ## Summary This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9, DC-9-80 and C-9 (military) series airplanes, and Model MD-88 airplanes, that requires revising the wiring of the air conditioning pneumatic supply control, if applicable, and revising the wiring of the pneumatic augmentation valve. This amendment is prompted by a report indicating that the pneumatic augmentation valve may go fully open when an engine fails during initial climb prior to deactivation of the second segment climb switch. The actions specified by this AD are intended to prevent opening of the pneumatic augmentation valve, which could result in significant loss of thrust from the remaining engine and consequent inadequate initial climb performance of the airplane. ## The airworthiness directive 99-22-08 MCDONNELL DOUGLAS: Amendment 39-11386. Docket 98-NM-382-AD. Applicability: Model DC-9-10, -20, -30, -40, and -50 series airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) series airplanes; Model MD-88 airplanes; and C-9 (military) series airplanes; as listed in the McDonnell Douglas Service Bulletin DC9-36-012, Revision 04, dated October 16, 1998; certificated in any category. NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration,or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Compliance: Required as indicated, unless accomplished previously. To prevent opening of the pneumatic augmentation valve during initial climb following an engine failure, which could result in significant loss of thrust on the remaining engine and consequent inadequate initial climb performance of the airplane, accomplish the following: Modification (a) Within 3 years after the effective date of this AD, revise the wiring of the air conditioning pneumatic supply control, if applicable, and revise the wiring of the pneumatic augmentation valve, in accordance with McDonnell Douglas Service Bulletin DC9-36-012, Revision 03, dated February 3, 1998, or Revision 04, dated October 16, 1998. Alternative Methods of Compliance (b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. Special Flight Permits (c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (d) The modification shall be done in accordance with McDonnell Douglas Service Bulletin DC9-36-012, Revision 03, dated February 3, 1998; or McDonnell Douglas Service Bulletin DC9-36-012, Revision 04, dated October 16, 1998; as applicable. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Dept. C1-L51 (2-60). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (e) This amendment becomes effective on November 30, 1999. ## Rule preamble ### Supplementary information A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9, DC-9-80 and C-9 (military) series airplanes, and Model MD-88 airplanes was published in the Federal Register on August 6, 1999 (64 FR 42868). That action proposed to require revising the wiring of the air conditioning pneumatic supply control, if applicable, and revising the wiring of the pneumatic augmentation valve. Comments Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received. The commenter supports the proposed rule. Conclusion After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. Cost Impact Thereare approximately 1,500 airplanes of the affected design in the worldwide fleet. The FAA estimates that 700 airplanes of U.S. registry will be affected by this AD, that it will take approximately between 1 to 6 work hours per airplane to accomplish the actions, and that the average labor rate is $60 per work hour. Required parts cost will be nominal. Based on these figures, the cost impact of this AD on U.S. operators is estimated to be between $42,000 and $252,000, or between $60 and $360 per airplane. The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. Regulatory Impact The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among thevarious levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new airworthiness directive: ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A6WE](https://openairdocs.org/tcds/A6WE): The Boeing Company; names 20 of 25 models: DC-9-12, DC-9-15F, MD-88, DC-9-41, DC-9-13, DC-9-34F, DC-9-81 (MD-81), DC-9-33F… ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 113 (113 by airframe model, 0 by engine model) - Makers: Mcdonnell Douglas 107, Douglas 6 Models with the most aircraft: - [Mcdonnell Douglas DC-9-83(MD-83)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-83-md-83): 49 aircraft (airframe model) - [Mcdonnell Douglas DC-9-82(MD-82)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-82-md-82): 22 aircraft (airframe model) - [Mcdonnell Douglas MD-88](https://openairdocs.org/model/mcdonnell-douglas-md-88): 14 aircraft (airframe model) - [Mcdonnell Douglas DC-9-87](https://openairdocs.org/model/mcdonnell-douglas-dc-9-87): 13 aircraft (airframe model) - [Mcdonnell Douglas DC-9-15F](https://openairdocs.org/model/mcdonnell-douglas-dc-9-15f): 3 aircraft (airframe model) - [Mcdonnell Douglas DC-9-33F](https://openairdocs.org/model/mcdonnell-douglas-dc-9-33f): 3 aircraft (airframe model) - [Douglas DC-9-83](https://openairdocs.org/model/douglas-dc-9-83): 1 aircraft (airframe model) - [Douglas DC9-15](https://openairdocs.org/model/douglas-dc9-15): 1 aircraft (airframe model) - [Douglas DC-9-15F](https://openairdocs.org/model/douglas-dc-9-15f): 1 aircraft (airframe model) - [Douglas DC-9-21](https://openairdocs.org/model/douglas-dc-9-21): 1 aircraft (airframe model) - [Douglas DC-9-32F](https://openairdocs.org/model/douglas-dc-9-32f): 1 aircraft (airframe model) - [Mcdonnell Douglas DC-9-32](https://openairdocs.org/model/mcdonnell-douglas-dc-9-32): 1 aircraft (airframe model) - [Mcdonnell Douglas DC-9-32F](https://openairdocs.org/model/mcdonnell-douglas-dc-9-32f): 1 aircraft (airframe model) - [Douglas DC-9-33F](https://openairdocs.org/model/douglas-dc-9-33f): 1 aircraft (airframe model) - [Mcdonnell Douglas DC-9-87 (MD-87)](https://openairdocs.org/model/mcdonnell-douglas-dc-9-87-md-87): 1 aircraft (airframe model) All 16 models: https://openairdocs.org/ad/99-22-08/models.md Every aircraft: https://openairdocs.org/ad/99-22-08/aircraft.md ## Related documents - [Proposed rule 98-NM-382-AD](https://openairdocs.org/proposed/98-NM-382-AD): Notice of proposed rulemaking (NPRM), published Aug 6, 1999 Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.