AD 78-09-05

final rule

Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes

AD Number
78-09-05
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Cessna Aircraft Company 336 Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337 Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337A Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337B Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337C Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337D Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337E Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337F Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337G Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337H Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company M337B Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company P337H Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337B Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337C Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337D Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337E Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337F Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337G Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company T337H Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes

Unsafe Condition

Cracking of the wing front and rear spar lower caps, front spar web and web doubler.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect the right and left wing front and rear spar lower cap and front spar web and web doubler at specified intervals using eddy current and dye penetrant methods. Replace cracked components in both wings before return to service. Report findings to FAA and adjust inspection intervals as allowed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 25 hours time-in-service after the effective date of this AD for airplanes not previously inspected, or within 500 hours time-in-service after the last inspection under prior ADs. Repetitive inspections every 500 hours for non-pressurized (5,000+ hours) or pressurized (10,000+ hours) airplanes, or 300 hours for those with low altitude operations as urged.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Cessna Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, P337H, M337B with specific serial ranges: 336-0001-0195, 337-0001-1193, 33701194-33701852, P3370001-P3370313, and all M337B serial numbers.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Wing Spar Caps and Web Doublers

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_78-09-05.html
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AD Number:
78-09-05
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E...Show more
Subject:
Wing Spar Caps and Web Doublers
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
05/11/1978
Make:
Cessna Aircraft Company
Model:
336 | 337 | 337A | 337B | 337C | 337D | 337E | 337F | 337G | 337H | M337B | P337H | T337B | T337C | ...Show more
Product Type:
Aircraft
Product Subtype:
Small Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
RGL Updated 12/19/2011: Corrected the FR page references to AD 76-10-11. We don't know if this was...Show more
AIRWORTHINESS DIRECTIVES FINAL RULES: 78-09-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-3202

AD NUMBER:   78-09-05

SUBJECT HEADING:   Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective May 11, 1978.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
78-09-05 CESSNA: Amendment 39-3202. Applies to the following models and serial number airplanes certificated in all categories:



MODELS	SERIAL NUMBERS
336	336-0001 through 336-0195
337, 337A, 337B, T337B,
337C, T337C, 337D and T337D	337-0001 through 337-1193

337E, T337E, 337F, T337F,
337G, 337H and T337H	33701194 through 33701852
T337G and P337H	P3370001 through P3370313
M337B	All serial numbers

Compliance: Required as indicated in accordance with Compliance Table I set forth in this AD or as otherwise set forth herein, unless already accomplished.

To detect cracking of the wing front and rear spar lower caps, front spar web and web doubler - In accordance with instructions set forth herein and in Cessna Multi-Engine Service Letter ME78-2, dated February 13, 1978, or later revisions:

I. At time intervals noted in Table I of this AD, inspect the right and left wing front and rear spar lower cap and front spar web and web doubler on airplanes having model and serial numbers shown below;



TABLE 1
COMPLIANCE TIMES

Airplane Type/
Operation	Total Time in
Service for each of the following:	Inspection Times for Spar
Cap - Inspections required
by Paragraph I.A.	Inspection Times for
Front Spar Web - Inspections
Required by Paragraph I.B.
	1) Front Spar
Lower Cap	Initial Inspection
in accordance
with this AD	Interval for
Repetitive
Inspections	Initial
Inspection	Interval for
Repetitive
Inspections*
	2) Rear Spar
Lower Cap
3) Front Spar
Web & Web
Doubler				
					
Non-Pressurized
(See Note 1)	0 to 4999	None	None	None	None
	5,000 & up	Within 25 hours time-in-service after the effective date
of this AD for those airplanes which
have not yet been inspected in accordance with
AD 76-10-11
or 73-04-02 or;
within 500 hours
time-in-service
after the last
inspection in
accordance with
AD 76-10-11 or
73-04-02.	500 hours	Within 25 hours time-in-service
after the effective date of this AD.	500 hours
					
Pressurized
(See Note 1)	0 to 9,999	None	None	None	None
	10,000 & up	Within 25 hours
time-in-service
after the effective
date of this AD
for those airplanes
which have not yet
been inspected in
accordance with
AD 76-10-11 or
73-04-02 or;
within 500 hours
time-in-service
after the last inspections
in accordance with
AD 76-10-11 or 73-04-02.	500 hours	Within 25 hours time-in-service
after the effective date of this AD.
	500 hours
NOTE 1:
For those airplanes
which have engaged
in contour or
terrain following
operations at low
altitudes, such
as power/pipeline
patrol, fish or
game spotting,
aerial applications,
police patrol, live-
stock management,
etc., Cessna
recommends and FAA strongly urges
inspections at
intervals shown to
the right of this
note.	0 to 2,999

3,000 & up	None

Within 25 hours
time-in-service
after the effective
date of this AD
for those airplanes which have
not yet been
inspected in
accordance with the
suggestion in
AD 76-10-11 or
73-04-02 or, within 300 hours time-
in-service after the last inspection in accordance with
AD 76-10-11 or
73-04-02.	None

300 hours	None

Within 25 hours time-in-service
after the effective date of this AD.	None

300 hours


*After initial inspection in
accordance
with this AD the compliance
time for
repetitive
inspections
may be adjusted to
allow compliance at the same
time as the
inspections
required by
paragraph
1A of this AD.

A. Front and rear spar lower cap inspection;


Model	Serial Numbers
336	336-0001 through 336-0195
337, 337A, 337B, T337B, 337C,
T337C, 337D, and T337D	337-0001 through 337-1193
337E, T337E, 337F, T337F, and 337G	33701194 through 33701548
T337G	P3370001 through P3370138
M337B	All serial numbers

1. Front spar lower cap inspection.

a. Inspect three fastener holes on the left wing and three fastener holes on the right wing for wing spar cracks using eddy current inspection procedures outlined in the above noted Cessna Service Letter. Figure 1 shows the area involved and the three fasteners (two NAS 221 screws at W.S. 64.41 and the jack point bolt hole at W.S. 68.45) that are to be inspected.

b. Remove the two NAS 221 screws at Wing Station 64.41 one at a time for this inspection and hold the boom fairing firmly against underlying thicknesses of material to insure proper eddy current probe depth settings during this inspection. A cross-section with the screws at W.S. 64.41 removed is shown in Figure 2. Figure 3 shows the spar assembly (less boom and wing skins) and the relationship of the lower cap to the other parts at the strut attachment. Figure 4 shows the spar cross-section thru the jack point bolt hole.









c. If cracks are found in either the right or left wing front spar lower cap during any inspection required by this AD, prior to approving the airplane for return to service replace the front spar lower cap in both the right and left wing with new spar caps.

2. Rear spar lower cap inspection.

a. Dye penetrant inspect the lower spar cap area between two and three inches (2nd rivet outboard of W.S. 66.00 rib) outboard of wing station 66.00 rib for spar cap cracks originating in the rivet hole in accordance with inspection provisions in the above noted Cessna Service Letter. Figures 5, 6 and 7 show the location of the area on the rear spar lower cap to be inspected.








b. If cracks are found in either the right or left wing rear spar lower cap during any inspection required by this AD, prior to approving the airplane for return to service replace the rear spar lower cap in both the right and left wing.

B. Front spar web and web doubler inspection;


Model	Serial Numbers
336	336-0001 through 336-0195
337, 337A, 337B, T337B, 337C,
T337C, 337D and T337D	337-0001 through 337-1193
337E, T337E, 337F, T337F, 337G,
337H and T337H	33701194 through 33701852
T337G and P337H	P3370001 through P3370313
M337B	All serial numbers

1. Remove wing root access panels and wing root fairings.

2. Visually inspect the radii of both the spar web and web doubler for cracks in the shaded critical area shown in Figure 8 of this AD.

3. If cracks are found in either the right or left wing front spar web or web doubler during any inspection required by this AD, prior to approving the airplane for return to service, replace the discrepant components.

II. Airplanes found to have cracked spar caps, webs or web doublers during inspections required by this AD may be flown in accordance with FAR 21.197 to a base where the component replacement can be accomplished.

III. Accomplish the repetitive inspections made mandatory by this AD on those spar caps, webs and web doublers replaced in accordance with this AD upon accumulation of the total times-in-service shown in Table I of this AD. Repetitive inspections "strongly urged" via Note 1 in Table I of this AD should also be accomplished on spar caps, webs and web doublers replaced in accordance with this AD upon accumulation of the total times-in-service shown in Note 1, Table I, of this AD.

IV. Notify in writing the Chief, Engineering and Manufacturing Branch, FAA, Central Region, of the location and length of any crack found during inspections required by this AD and also the total time in service of the component at the time the crack was discovered. (Reporting approved by the Office of Management and Budget under OMB NO. 04-R0174.)

V. The time interval for repetitive inspections required by this AD, after compliance with initial inspection requirements, can be adjusted up to 25 hours to allow accomplishment of these inspections at regular scheduled maintenance periods.

VI. Equivalent methods of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This AD supersedes AD 76-10-11, Amendment 39-2621 (41 FR 22045, 22046, 22047 and 22048).

This Amendment becomes effective May 11, 1978.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_78-09-05.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
78-09-05
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E...Show more
Subject:
Wing Spar Caps and Web Doublers
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
05/11/1978
Make:
Cessna Aircraft Company
Model:
336 | 337 | 337A | 337B | 337C | 337D | 337E | 337F | 337G | 337H | M337B | P337H | T337B | T337C | ...Show more
Product Type:
Aircraft
Product Subtype:
Small Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
RGL Updated 12/19/2011: Corrected the FR page references to AD 76-10-11. We don't know if this was...Show more
AIRWORTHINESS DIRECTIVES FINAL RULES: 78-09-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-3202

AD NUMBER:   78-09-05

SUBJECT HEADING:   Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective May 11, 1978.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
78-09-05 CESSNA: Amendment 39-3202. Applies to the following models and serial number airplanes certificated in all categories:



MODELS	SERIAL NUMBERS
336	336-0001 through 336-0195
337, 337A, 337B, T337B,
337C, T337C, 337D and T337D	337-0001 through 337-1193

337E, T337E, 337F, T337F,
337G, 337H and T337H	33701194 through 33701852
T337G and P337H	P3370001 through P3370313
M337B	All serial numbers

Compliance: Required as indicated in accordance with Compliance Table I set forth in this AD or as otherwise set forth herein, unless already accomplished.

To detect cracking of the wing front and rear spar lower caps, front spar web and web doubler - In accordance with instructions set forth herein and in Cessna Multi-Engine Service Letter ME78-2, dated February 13, 1978, or later revisions:

I. At time intervals noted in Table I of this AD, inspect the right and left wing front and rear spar lower cap and front spar web and web doubler on airplanes having model and serial numbers shown below;



TABLE 1
COMPLIANCE TIMES

Airplane Type/
Operation	Total Time in
Service for each of the following:	Inspection Times for Spar
Cap - Inspections required
by Paragraph I.A.	Inspection Times for
Front Spar Web - Inspections
Required by Paragraph I.B.
	1) Front Spar
Lower Cap	Initial Inspection
in accordance
with this AD	Interval for
Repetitive
Inspections	Initial
Inspection	Interval for
Repetitive
Inspections*
	2) Rear Spar
Lower Cap
3) Front Spar
Web & Web
Doubler				
					
Non-Pressurized
(See Note 1)	0 to 4999	None	None	None	None
	5,000 & up	Within 25 hours time-in-service after the effective date
of this AD for those airplanes which
have not yet been inspected in accordance with
AD 76-10-11
or 73-04-02 or;
within 500 hours
time-in-service
after the last
inspection in
accordance with
AD 76-10-11 or
73-04-02.	500 hours	Within 25 hours time-in-service
after the effective date of this AD.	500 hours
					
Pressurized
(See Note 1)	0 to 9,999	None	None	None	None
	10,000 & up	Within 25 hours
time-in-service
after the effective
date of this AD
for those airplanes
which have not yet
been inspected in
accordance with
AD 76-10-11 or
73-04-02 or;
within 500 hours
time-in-service
after the last inspections
in accordance with
AD 76-10-11 or 73-04-02.	500 hours	Within 25 hours time-in-service
after the effective date of this AD.
	500 hours
NOTE 1:
For those airplanes
which have engaged
in contour or
terrain following
operations at low
altitudes, such
as power/pipeline
patrol, fish or
game spotting,
aerial applications,
police patrol, live-
stock management,
etc., Cessna
recommends and FAA strongly urges
inspections at
intervals shown to
the right of this
note.	0 to 2,999

3,000 & up	None

Within 25 hours
time-in-service
after the effective
date of this AD
for those airplanes which have
not yet been
inspected in
accordance with the
suggestion in
AD 76-10-11 or
73-04-02 or, within 300 hours time-
in-service after the last inspection in accordance with
AD 76-10-11 or
73-04-02.	None

300 hours	None

Within 25 hours time-in-service
after the effective date of this AD.	None

300 hours


*After initial inspection in
accordance
with this AD the compliance
time for
repetitive
inspections
may be adjusted to
allow compliance at the same
time as the
inspections
required by
paragraph
1A of this AD.

A. Front and rear spar lower cap inspection;


Model	Serial Numbers
336	336-0001 through 336-0195
337, 337A, 337B, T337B, 337C,
T337C, 337D, and T337D	337-0001 through 337-1193
337E, T337E, 337F, T337F, and 337G	33701194 through 33701548
T337G	P3370001 through P3370138
M337B	All serial numbers

1. Front spar lower cap inspection.

a. Inspect three fastener holes on the left wing and three fastener holes on the right wing for wing spar cracks using eddy current inspection procedures outlined in the above noted Cessna Service Letter. Figure 1 shows the area involved and the three fasteners (two NAS 221 screws at W.S. 64.41 and the jack point bolt hole at W.S. 68.45) that are to be inspected.

b. Remove the two NAS 221 screws at Wing Station 64.41 one at a time for this inspection and hold the boom fairing firmly against underlying thicknesses of material to insure proper eddy current probe depth settings during this inspection. A cross-section with the screws at W.S. 64.41 removed is shown in Figure 2. Figure 3 shows the spar assembly (less boom and wing skins) and the relationship of the lower cap to the other parts at the strut attachment. Figure 4 shows the spar cross-section thru the jack point bolt hole.









c. If cracks are found in either the right or left wing front spar lower cap during any inspection required by this AD, prior to approving the airplane for return to service replace the front spar lower cap in both the right and left wing with new spar caps.

2. Rear spar lower cap inspection.

a. Dye penetrant inspect the lower spar cap area between two and three inches (2nd rivet outboard of W.S. 66.00 rib) outboard of wing station 66.00 rib for spar cap cracks originating in the rivet hole in accordance with inspection provisions in the above noted Cessna Service Letter. Figures 5, 6 and 7 show the location of the area on the rear spar lower cap to be inspected.








b. If cracks are found in either the right or left wing rear spar lower cap during any inspection required by this AD, prior to approving the airplane for return to service replace the rear spar lower cap in both the right and left wing.

B. Front spar web and web doubler inspection;


Model	Serial Numbers
336	336-0001 through 336-0195
337, 337A, 337B, T337B, 337C,
T337C, 337D and T337D	337-0001 through 337-1193
337E, T337E, 337F, T337F, 337G,
337H and T337H	33701194 through 33701852
T337G and P337H	P3370001 through P3370313
M337B	All serial numbers

1. Remove wing root access panels and wing root fairings.

2. Visually inspect the radii of both the spar web and web doubler for cracks in the shaded critical area shown in Figure 8 of this AD.

3. If cracks are found in either the right or left wing front spar web or web doubler during any inspection required by this AD, prior to approving the airplane for return to service, replace the discrepant components.

II. Airplanes found to have cracked spar caps, webs or web doublers during inspections required by this AD may be flown in accordance with FAR 21.197 to a base where the component replacement can be accomplished.

III. Accomplish the repetitive inspections made mandatory by this AD on those spar caps, webs and web doublers replaced in accordance with this AD upon accumulation of the total times-in-service shown in Table I of this AD. Repetitive inspections "strongly urged" via Note 1 in Table I of this AD should also be accomplished on spar caps, webs and web doublers replaced in accordance with this AD upon accumulation of the total times-in-service shown in Note 1, Table I, of this AD.

IV. Notify in writing the Chief, Engineering and Manufacturing Branch, FAA, Central Region, of the location and length of any crack found during inspections required by this AD and also the total time in service of the component at the time the crack was discovered. (Reporting approved by the Office of Management and Budget under OMB NO. 04-R0174.)

V. The time interval for repetitive inspections required by this AD, after compliance with initial inspection requirements, can be adjusted up to 25 hours to allow accomplishment of these inspections at regular scheduled maintenance periods.

VI. Equivalent methods of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This AD supersedes AD 76-10-11, Amendment 39-2621 (41 FR 22045, 22046, 22047 and 22048).

This Amendment becomes effective May 11, 1978.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.