Airworthiness Directive · Amendment 39-11709 · McDonnell Douglas Model DC-8 Series Airplanes
McDonnell Douglas Model DC-8 Series Airplanes
Model DC-8 series airplanes that have been converted from a passenger to a cargo-carrying (“freighter”) configuration in accordance with Supplemental Type Certificate (STC) SA1802SO or SA421NW; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (g) 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.
This amendment supersedes an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8 series airplanes, that currently requires a revision to the Airplane Flight Manual Supplement to ensure that the main deck cargo door is closed, latched, and locked; repetitive inspections of the wire bundle and door latch rollers to detect damage; and repair or replacement of damaged components. This amendment requires, among other actions, modification of the indication and hydraulic systems of the main deck cargo door, and installation of a means to prevent pressurization to an unsafe level if the main deck cargo door is not closed, latched, and locked. This amendment is prompted by the FAA's determination that certain main deck cargo door systems do not provide an adequate level of safety; the latching and locking mechanisms are not of adequate design to prevent structural deformation in the event of component jamming; and that there is an absence of a means to prevent pressurization to an unsafe level if the main deck cargo door is not closed, latched, and locked. The actions specified by this AD are intended to prevent opening of the cargo door while the airplane is in flight, and consequent rapid decompression of the airplane including possible loss of the door, flight control, or severe structural damage.
To prevent opening of the cargo door while the airplane is in flight, and consequent rapid decompression of the airplane including possible loss of the door, flight control, or severe structural damage, accomplish the following:
(a) Within 7 days after January 21, 1992 (the effective date of AD 92-02-05, amendment 39-8141), and thereafter at intervals not to exceed 100 hours time-in-service, perform the following inspections:
(1) Inspect the cargo door wire bundle between the exit point of the cargo liner and the attachment point on the cargo door to detect crimped, frayed, or chafed wires; and inspect for damaged, loose, or missing hardware mounting components. Prior to further flight, repair any damaged wiring or hardware mounting components in accordance with FAA-approved maintenance procedures.
(2) Inspect the cargo door latch rollers in the lower sill of the cargo door opening of the airplane to ensure that all twelve rollers can be freely rotated by hand. Prior to further flight, replace any discrepant roller components found, and repair any rollers that cannot be rotated freely by hand, in accordance with FAA-approved maintenance procedures.
(b) Within 7 days after November 17, 1993 (the effective date of AD 93-20-02, amendment 39-8709), revise the Limitations Section of the appropriate FAA-approved Airplane Flight Manual Supplement (AFMS) by replacing item 5 in the AFMS for SA1802SO, and item 6 in the AFMS for SA421NW, with the following. (This may be accomplished by inserting a copy of this AD into the AFMS.)
“Prior to initiating the cargo door closing sequence, a flight crew member must verify that the cargo door warning light is illuminated. After the door closing sequence is complete, and visual verification has been made that the latches are closed and the lockpins are properly engaged, a flight crew member must verify that the cargo door warning light is extinguished, and then conduct a PRESS-TO-TEST of the warning light to ensure that the light is operational. Pull the cargo door circuit breakers labeled “pump” and “valve” prior to takeoff. Methods for documentation of compliance with the preceding procedures must be approved by the FAA Principal Maintenance Inspector (PMI).”
(c) Except as provided by paragraph (f) of this AD, within 30 days after the effective date of this AD, unless previously accomplished within the last 18 months prior to the effective date of this AD, replace the circuit breakers of the main deck cargo door labeled “pump” and “valve” with new circuit breakers.
(d) Within 18 months after the effective date of this AD, modify the mechanical and hydraulic systems of the main deck cargo door, in accordance with National Aircraft Service, Inc. (NASI) Service Bulletin SB-99-01, Revision A, dated October 15, 1999.
(e) Within 18 months after the effective date of this AD, modify the indication system of the main deck cargo door to indicate to the pilots whether the main deck cargo door is closed, latched, and locked; install a means to visually inspect the locking mechanism of the main deck cargo door; install a means to remove power to the door while the airplane is in flight; and install a means to prevent pressurization to an unsafe level if the main deck cargo door is not closed, latched, and locked; in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.
Note 2: Installation of NASI Vent Door System STC ST01116CH, is an approved means of compliance with the requirements of paragraph (e) of this AD.
(f) Compliance with both paragraphs (d) and (e) of this AD constitutes terminating action for the requirements of both paragraphs (a) and (b) of this AD, and the AFMS revision required by paragraph (b) of this AD may be removed. Compliance with paragraph (e) of this AD within 30 days after the effective date of this AD eliminates the requirement to comply with paragraph (c) of this AD.
(g)(1) 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 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO.
(2) Alternative methods of compliance to paragraph (a) of AD 93-20-02, amendment 39-8709, approved previously in accordance with that AD, are approved as alternative methods of compliance with only paragraph (a) of this AD.
(3) Alternative methods of compliance to paragraph (b) of AD 93-20-02, amendment 39-8709, approved previously in accordance with that AD, are approved as alternative methods of compliance with only paragraph (b) of this AD.
