2024-23101. Airworthiness Directives; The Boeing Company Airplanes

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
One-time inspection	3 work-hours × $85 per hour = $255	$0	$255	$33,915
Inspection due to certain conditions	3 work-hours × $85 per hour = $255	0	255	33,915

The FAA estimates the following costs to do any necessary reporting that would be required based on the results of the inspection. The FAA has no way of determining the number of aircraft that might need this reporting:

On-Condition Costs

Action	Labor cost	Parts cost	Cost per product
Reporting	1 work-hours × $85 per hour = $85	$0	$85

The FAA has received no definitive data on which to base the cost estimates for the on-condition repair specified in this AD.

Paperwork Reduction Act

A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a currently valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to take approximately 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. All responses to this collection of information are mandatory. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to: Information Collection Clearance Officer, Federal Aviation Administration, 10101 Hillwood Parkway, Fort Worth, TX 76177-1524.

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.

The FAA is 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

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, and

(2) Will not affect intrastate aviation in Alaska.

List of Subjects in 14 CFR Part 39

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

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:

2024-20-02 The Boeing Company: Amendment 39-22861; Docket No. FAA-2024-2324; Project Identifier AD-2024-00514-T.

(a) Effective Date

This airworthiness directive (AD) is effective October 21, 2024.

(b) Affected ADs

None.

(c) Applicability

This AD applies to all The Boeing Company airplanes identified in paragraphs (c)(1) through (6) of this AD, certificated in any category.

(1) Model 717-200 airplanes.

(2) Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, and DC-9-15F airplanes. ( print page 80732)

(3) Model DC-9-21 airplanes.

(4) Model DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A, C-9B), DC-9-33F, DC-9-34, and DC-9-34F airplanes.

(5) Model DC-9-41 airplanes.

(6) Model DC-9-51 airplanes.

(d) Subject

Air Transport Association (ATA) of America Code 53, Fuselage.

(e) Unsafe Condition

This AD was prompted by a report of cracked and severed structure found in the aft fuselage cant bulkhead at station (STA) 1178.225 and vertical stabilizer rear spar installation. The FAA is issuing this AD to address cracked and severed structure in the aft fuselage cant bulkhead and vertical stabilizer rear spar. The unsafe condition, if not addressed, could result in reduced structural integrity of the airplane.

(f) Compliance

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

(g) One-Time Inspection

Within 45 days after the effective date of this AD, do a detailed inspection of the cant bulkhead and vertical stabilizer rear spar structure for any crack, in accordance with table 1 of the applicable material identified in paragraph (g)(1) or (2) of this AD.

(1) For Model 717-200 airplanes: Boeing Multi Operator Message MOM-MOM-24-0457-01B(R1), dated September 4, 2024.

(2) For Model 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, C-9B), DC-9-33F, DC-9-34, DC-9-34F, DC-9-41, and DC-9-51 airplanes: Boeing Multi Operator Message MOM-MOM-24-0456-01B(R1), dated September 4, 2024.

(h) Repair for One-Time Inspection

If any crack is found during the detailed inspection required by paragraph (g) of this AD, repair the crack before further flight using a method approved in accordance with the procedures specified in paragraph (o) of this AD.

(i) Definitions

For the purposes of paragraphs (j) through (m) of this AD, the following terms are defined as follows.

(1) A “detailed inspection” is an intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate by the inspector. Inspection aids such as mirrors, magnifying lenses, etc. may be used. Surface cleaning and elaborate access procedures may be required.

(2) A “discrepancy” includes buckles, distortion, cracks, loose or missing fasteners, or any other obvious indication of damage.

(3) A “high drag/side load or unusual ground handling” condition is a result of one or more of the pilot-reported conditions specified in paragraphs (i)(3)(i) through (iv) of this AD.

(i) Skid or over-run from a prepared surface to an unprepared surface.

(ii) Landing short of the prepared surface.

(iii) Landing with two or more tires deflated.

(iv) Ground operations of a heavy aircraft during push back, prior to takeoff or after landing on unstable surface conditions like ice, snow, mud, soft pavement, or sand.

(4) A “hard landing” is when an aircraft touches down on the runway with more force or velocity than is considered normal or desirable.

(5) An “overweight landing” is a landing at a weight that is more than the maximum certificated landing weight.

(6) “Severe turbulence” or “rough air (turbulence)” is turbulence (including gusts) that can result in abnormal and abrupt changes in aircraft altitude, attitude, and airspeed.

(7) An “excessive maneuver” is a maneuver that results in severe and abnormal aircraft altitude or attitude changes due to rapid or large flight control inputs, i.e. control column, rudder pedals, or control wheel.

(8) “High compressive loads to the hydraulic tail bumper/strut” or “high compressive loads to the auxiliary gear (tail bumper)” is any loading event, such as a tail strike, tail skid, etc., that has the potential to move the indicating pin of the hydraulic tail bumper/strut or auxiliary gear (tail bumper) to the vertical position.

(j) Report for One-Time Inspection Findings

If any crack is found during the detailed inspection required by paragraph (g) of this AD, at the applicable time specified in paragraph (j)(1) or (2) of this AD, submit a report of positive findings to The Boeing Company via the Boeing Communication System (BCS). The report must include the crack size, crack location, and whether or not airplane maintenance records show any unscheduled maintenance checks due to severe turbulence or an excessive maneuver, high drag/side loads or unusual ground handling, a hard or overweight landing, or high compressive loads to the hydraulic tail bumper/strut or auxiliary gear (tail bumper).

(1) If the inspection was done on or after the effective date of this AD: Submit the report within 10 days after the inspection.

(2) If the inspection was done before the effective date of this AD: Submit the report within 10 days after the effective date of this AD.

(k) Conditional Inspections for Model 717-200 Airplanes

As of 45 days after the effective date of this AD: If a Model 717-200 airplane experiences high drag/side loads or unusual ground handling, a hard or overweight landing, severe turbulence or an excessive maneuver, or high compressive loads to the hydraulic tail bumper/strut: Do a detailed inspection of the cant bulkhead at STA 1178.225, left and right sides, between longerons 11L through 11R at the forward and aft surfaces; upper cap; upper (cap) doubler; bulkhead webs and doublers; stiffeners; lower tee cap and strap; and vertical stabilizer rear spar cap and web for any discrepancy.

Note 1 to paragraph (k):

Guidance for doing the inspection required by paragraph (k) of this AD due to high drag/side loads or unusual ground handling can be found in Subtask 05-51-03-210-005, steps (9) and (9)(a), of Boeing 717 Aircraft Maintenance Manual (AMM) Temporary Revision 05-1003, High Drag/Side Loads or Unusual Ground Handling Conditions—Inspection/Check, dated September 10, 2024.

Note 2 to paragraph (k):

Guidance for doing the inspection required by paragraph (k) of this AD due to a hard or overweight landing can be found in Subtask 05-51-04-210-028, steps (6)(a) and (6)(a)(1), of Boeing 717 AMM Temporary Revision 05-1004, Hard or Overweight Landing—Inspection/Check, dated September 10, 2024.

Note 3 to paragraph (k):

Guidance for doing the inspection required by paragraph (k) of this AD due to severe turbulence or an excessive maneuver can be found in Subtask 05-51-02-210-005, steps (6)(a) and (6)(a)(1), of Boeing 717 AMM Temporary Revision 05-1005, Severe Turbulence or Excessive Maneuver Conditions—Inspection/Check, dated September 10, 2024.

Note 4 to paragraph (k):

Guidance for doing the inspection required by paragraph (k) of this AD due to high compressive loads to the hydraulic tail bumper/strut can be found in Subtask 32-71-04-211-001, step (2), of Boeing 717 AMM Temporary Revision 32-1001, Hydraulic Tail Bumper—Inspection/Check, dated September 13, 2024.

(l) Conditional Inspections for Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 Series Airplanes

As of 45 days after the effective date of this AD: If a Model 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, C-9B), DC-9-33F, DC-9-34, DC-9-34F, DC-9-41, or DC-9-51 airplane experiences high drag/side loads or unusual ground handling, a hard or overweight landing, an excessive maneuver or rough air (turbulence), or high compressive loads to the auxiliary gear (tail bumper): Do a detailed inspection of the cant bulkhead at the applicable STA specified in table 1 to paragraph (l) of this AD, left and right sides, between longerons 11L through 11R at the forward and aft surfaces; upper cap; upper (cap) doubler; bulkhead webs and doublers; stiffeners; lower tee cap and strap; and vertical stabilizer rear spar cap and web for any discrepancy. ( print page 80733)

Table 1 to Paragraph ( l )—Applicable STA

Model	Paragraph (l) of this AD
DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, and DC-9-21 airplanes	STA 942.225
DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-32F (C-9A, C-9B), DC-9-33F, DC-9-34, and DC-9-34F airplanes	STA 1121.225
DC-9-41 airplanes	STA 1197.225
DC-9-51 airplanes	STA 1292.225