AD 97-21-06

final rule

Airworthiness Directives; CASA Model CN-235 Airplanes

AD Number
97-21-06
Status
final_rule
Effective Date
Product Category
aircraft
Docket
96-NM-137-AD
FR Citation
This information is not available.
Technical illustration of an aircraft flight control surface and actuator
Problem area Flight controls

Applicability

TypeManufacturerModelDetails
aircraft EADS CASA CN-235 Airworthiness Directives; CASA Model CN-235 Airplanes
aircraft EADS CASA CN-235-100 Airworthiness Directives; CASA Model CN-235 Airplanes
aircraft EADS CASA CN-235-200 Airworthiness Directives; CASA Model CN-235 Airplanes

Unsafe Condition

Failure of the elevator and/or rudder assemblies due to stress corrosion cracking in the torsion tubes and fittings, which could result in loss of control of the elevator and/or rudder.

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

Required Actions

Conduct a visual inspection of the torsion tubes on the elevator and rudder assemblies to detect stress corrosion cracking per CASA Service Bulletins. If cracking is found, replace cracked parts with new original design parts or newly-designed parts as specified, and repeat inspections at intervals. Replace all original design parts with newly-designed parts within 2 years after the effective date.

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

Compliance Time

Prior to further flight if cracking is detected. For airplanes with over 600 hours or 1,000 landings as of the effective date: within 50 hours time-in-service, 100 landings, or 3 months after the effective date. For others: within 600 hours, 1,000 landings, or 6 months after the effective date. Final replacement of original parts required within 2 years after the effective date.

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

Affected Aircraft

CASA Model CN-235, CN-235-100, CN-235-200 airplanes listed in CASA Service Bulletins SB-235-27-05 (non-military) and SB-235-27-05M (military), certificated in any category.

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

Federal Register Abstract

Torsion Tubes and Fittings

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_97-21-06.html
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AD Number:
97-21-06
Document Type:
AD Final Rules
Docket Number:
96-NM-137-AD
Subject Heading:
Airworthiness Directives; CASA Model CN-235 Airplanes
Subject:
Torsion Tubes and Fittings
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
11/24/1997
Make:
EADS CASA
Model:
CN-235 | CN-235-100 | CN-235-200
Product Type:
Aircraft
Product Subtype:
Large Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 97-21-06
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   96-NM-137-AD

AMENDMENT:   39-10159

AD NUMBER:   97-21-06

SUBJECT HEADING:   Airworthiness Directives; CASA Model CN-235 Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective November 24, 1997.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
97-21-06 CASA: Amendment 39-10159. Docket 96-NM-137-AD.
Applicability: CASA Model CN-235 airplanes; as listed in CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (non-military airplanes), and CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (military airplanes); 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 (e) 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 loss of control of the elevator and/or rudder, due to failure of the elevator and/or rudder assemblies as a result of stress corrosion cracking in the torsion tubes and fittings, accomplish the following:

NOTE 2: Actions required by this AD that were accomplished previous to the effective date of this AD, and in accordance with earlier versions of the specified CASA service bulletins, are considered acceptable for compliance with the applicable requirements of this AD.

(a) At the applicable time specified in either paragraph (a)(1) or (a)(2) of this AD, conduct a visual inspection of the torsion (torsion) tubes on the elevator and rudder assemblies to detect stress corrosion cracking, in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (for non-military airplanes) or CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (for military airplanes), as applicable.

(1) For airplanes that have accumulated more than 600 total hours time-in-service, or more than 1,000 total landings, as of the effective date of this AD: Conduct the inspection required by paragraph (a) of this AD prior to the accumulation of 50 hours time-in-service, or 100 landings, or within 3 months, after the effective date of this AD, whichever occurs first.

(2) For all other airplanes: Conduct the inspection required by paragraph (a) of this AD prior to the accumulation of 600 total hours time-in-service, or 1,000 total landings, or within 6 months, after the effective date of this AD, whichever occurs first.

(b) If no cracking is detected during the inspection required by paragraph (a) of this AD, repeat that inspection at intervals not to exceed 600 hours time-in-service, or 1,000 landings, or 6 months, whichever occurs first.

(c) If any cracking is detected during the inspection required by paragraph (a) of this AD, prior to further flight, accomplish either paragraph (c)(1) or (c)(2) of this AD.

(1) Replace cracked parts with new parts of the original design, in accordance with the service bulletin. After replacement, repeat the visual inspection required by paragraph (a) of this AD at intervals not to exceed 600 hours time-in-service, or 1,000 landings, or 6 months, whichever occurs first. OR

(2) Replace cracked parts with newly-designed parts, in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (for non-military airplanes); or CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (for military airplanes); as applicable. This replacement constitutes terminating action for the repetitive visual inspections of that part required by paragraph (b) of this AD.

(d) Within 2 years after the effective date of this AD, replace all original design parts comprising the torsion tube assemblies on the elevator and rudder assemblies with newly-designed parts, in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (for non-military airplanes); or CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (for military airplanes); as applicable. This action constitutes terminating action for the inspection requirements of this AD.

(e) 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, Standardization Branch, ANM-113, 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, Standardization Branch, ANM-113.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(f) Special flight permits may be issued in accordance with sections 21.197 and P21.199 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.

(g) The actions shall be done in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993; and CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996; as applicable; which contain the specified effective pages:

Service Bulletin
Referenced and Date	Page Number	Revision Level
Shown on Page	Date
Shown on Page
SB-235-27-05,
Revision 1,
September 29, 1993	1, 2

3-23	1

Original	September 29, 1993

February 5, 1993
SB-235-27-05M,
Revision 2,
January 25, 1996	1

2-23	2

Original	January 25, 1996

October 28, 1991

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 Construcciones Aeronauticas, S.A., Getafe, Madrid, Spain. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

NOTE 4: The subject of this AD is addressed in Spanish airworthiness directive 06/94, dated August 1994.

(h) This amendment becomes effective on November 24, 1997.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_97-21-06.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
97-21-06
Document Type:
AD Final Rules
Docket Number:
96-NM-137-AD
Subject Heading:
Airworthiness Directives; CASA Model CN-235 Airplanes
Subject:
Torsion Tubes and Fittings
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
11/24/1997
Make:
EADS CASA
Model:
CN-235 | CN-235-100 | CN-235-200
Product Type:
Aircraft
Product Subtype:
Large Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 97-21-06
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   96-NM-137-AD

AMENDMENT:   39-10159

AD NUMBER:   97-21-06

SUBJECT HEADING:   Airworthiness Directives; CASA Model CN-235 Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective November 24, 1997.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
97-21-06 CASA: Amendment 39-10159. Docket 96-NM-137-AD.
Applicability: CASA Model CN-235 airplanes; as listed in CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (non-military airplanes), and CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (military airplanes); 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 (e) 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 loss of control of the elevator and/or rudder, due to failure of the elevator and/or rudder assemblies as a result of stress corrosion cracking in the torsion tubes and fittings, accomplish the following:

NOTE 2: Actions required by this AD that were accomplished previous to the effective date of this AD, and in accordance with earlier versions of the specified CASA service bulletins, are considered acceptable for compliance with the applicable requirements of this AD.

(a) At the applicable time specified in either paragraph (a)(1) or (a)(2) of this AD, conduct a visual inspection of the torsion (torsion) tubes on the elevator and rudder assemblies to detect stress corrosion cracking, in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (for non-military airplanes) or CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (for military airplanes), as applicable.

(1) For airplanes that have accumulated more than 600 total hours time-in-service, or more than 1,000 total landings, as of the effective date of this AD: Conduct the inspection required by paragraph (a) of this AD prior to the accumulation of 50 hours time-in-service, or 100 landings, or within 3 months, after the effective date of this AD, whichever occurs first.

(2) For all other airplanes: Conduct the inspection required by paragraph (a) of this AD prior to the accumulation of 600 total hours time-in-service, or 1,000 total landings, or within 6 months, after the effective date of this AD, whichever occurs first.

(b) If no cracking is detected during the inspection required by paragraph (a) of this AD, repeat that inspection at intervals not to exceed 600 hours time-in-service, or 1,000 landings, or 6 months, whichever occurs first.

(c) If any cracking is detected during the inspection required by paragraph (a) of this AD, prior to further flight, accomplish either paragraph (c)(1) or (c)(2) of this AD.

(1) Replace cracked parts with new parts of the original design, in accordance with the service bulletin. After replacement, repeat the visual inspection required by paragraph (a) of this AD at intervals not to exceed 600 hours time-in-service, or 1,000 landings, or 6 months, whichever occurs first. OR

(2) Replace cracked parts with newly-designed parts, in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (for non-military airplanes); or CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (for military airplanes); as applicable. This replacement constitutes terminating action for the repetitive visual inspections of that part required by paragraph (b) of this AD.

(d) Within 2 years after the effective date of this AD, replace all original design parts comprising the torsion tube assemblies on the elevator and rudder assemblies with newly-designed parts, in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993 (for non-military airplanes); or CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996 (for military airplanes); as applicable. This action constitutes terminating action for the inspection requirements of this AD.

(e) 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, Standardization Branch, ANM-113, 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, Standardization Branch, ANM-113.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(f) Special flight permits may be issued in accordance with sections 21.197 and P21.199 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.

(g) The actions shall be done in accordance with CASA Service Bulletin SB-235-27-05, Revision 1, dated September 29, 1993; and CASA Service Bulletin SB-235-27-05M, Revision 2, dated January 25, 1996; as applicable; which contain the specified effective pages:

Service Bulletin
Referenced and Date	Page Number	Revision Level
Shown on Page	Date
Shown on Page
SB-235-27-05,
Revision 1,
September 29, 1993	1, 2

3-23	1

Original	September 29, 1993

February 5, 1993
SB-235-27-05M,
Revision 2,
January 25, 1996	1

2-23	2

Original	January 25, 1996

October 28, 1991

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 Construcciones Aeronauticas, S.A., Getafe, Madrid, Spain. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

NOTE 4: The subject of this AD is addressed in Spanish airworthiness directive 06/94, dated August 1994.

(h) This amendment becomes effective on November 24, 1997.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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