AD 84-24-51 R1
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-7-1 | Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-100 | Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-101 | Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-102 | Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-103 | Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes |
Unsafe Condition
Incorrect operation of the airplane during flight in icing conditions due to inadequate AFM guidance on engine ignition settings and airframe switch positions.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise Section 2 of the AFM within 60 days after the effective date by updating paragraph 2.21 title, modifying item 8 in paragraph 2.21.1, and adding a note about manual engine ignition. Provide updated information to flight crews.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within 60 days after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
DeHavilland Model DHC-7 series airplanes, certificated in any category
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
AFM Change -- Icing Conditions
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_84-24-51_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 84-24-51 R1 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes Subject: AFM Change -- Icing Conditions Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/03/1987 Make: Viking Air Limited Model: DHC-7-1 | DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 84-24-51 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5661 AD NUMBER: 84-24-51 R1 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes ACTION: SUMMARY: DATES: Effective August 3, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 84-24-51 R1 THE DeHAVILLAND AIRCRAFT COMPANY OF CANADA, A DIVISION OF BOEING OF CANADA, LTD.: Amendment 39-5030 as amended by Amendment 39-5661. Applies to all Model DHC-7 series airplanes, certificated in any category. Compliance is required as indicated, unless previously accomplished. To ensure correct operation of the airplane during flight in icing conditions, accomplish the following: A. Within 60 days after the effective date of this AD, revise Section 2 of the FAA- approved DHC-7 Airplane Flight Manual (AFM), Revision 29, dated July 26, 1985, as follows, and provide this information to the flight crews: 1. Change the title of paragraph 2.21 to read: "2.21. Flight in Icing Conditions (Visible Moisture and/or Precipitation at Temperatures Below Plus 5 Degrees Centigrade True Outside Air Temperature, or Plus 13 Degrees Centigrade Indicated Outside Air Temperature When Correction Chart Figure 4-4-4 is Not Used)." 2. Change item 8 in paragraph 2.21.1 to read: "8. Ignition switch - Manual (if required)." 3. Add the following note at the end of paragraph 2.21.1: "NOTE: Manual (continuous) engine ignition is an automatic function when AIRFRAME - FAST/SLW switch is at fast or slow position." B. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. C. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, New York Aircraft Certification Office, FAA, New England Region. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to de Havilland Aircraft Company of Canada, A Division of Boeing of Canada, Ltd., Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information may be examined at FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or at FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York. Amendment 39-5030 became effective April 16, 1985. This amendment, 39-5661, becomes effective August 3, 1987. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_84-24-51_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 84-24-51 R1 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes Subject: AFM Change -- Icing Conditions Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/03/1987 Make: Viking Air Limited Model: DHC-7-1 | DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 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: 84-24-51 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5661 AD NUMBER: 84-24-51 R1 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Series Airplanes ACTION: SUMMARY: DATES: Effective August 3, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 84-24-51 R1 THE DeHAVILLAND AIRCRAFT COMPANY OF CANADA, A DIVISION OF BOEING OF CANADA, LTD.: Amendment 39-5030 as amended by Amendment 39-5661. Applies to all Model DHC-7 series airplanes, certificated in any category. Compliance is required as indicated, unless previously accomplished. To ensure correct operation of the airplane during flight in icing conditions, accomplish the following: A. Within 60 days after the effective date of this AD, revise Section 2 of the FAA- approved DHC-7 Airplane Flight Manual (AFM), Revision 29, dated July 26, 1985, as follows, and provide this information to the flight crews: 1. Change the title of paragraph 2.21 to read: "2.21. Flight in Icing Conditions (Visible Moisture and/or Precipitation at Temperatures Below Plus 5 Degrees Centigrade True Outside Air Temperature, or Plus 13 Degrees Centigrade Indicated Outside Air Temperature When Correction Chart Figure 4-4-4 is Not Used)." 2. Change item 8 in paragraph 2.21.1 to read: "8. Ignition switch - Manual (if required)." 3. Add the following note at the end of paragraph 2.21.1: "NOTE: Manual (continuous) engine ignition is an automatic function when AIRFRAME - FAST/SLW switch is at fast or slow position." B. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. C. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, New York Aircraft Certification Office, FAA, New England Region. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to de Havilland Aircraft Company of Canada, A Division of Boeing of Canada, Ltd., Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information may be examined at FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or at FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York. Amendment 39-5030 became effective April 16, 1985. This amendment, 39-5661, becomes effective August 3, 1987. FOOTER:
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Retrieved: Apr 8, 2026
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