AD 73-16-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aviat Aircraft Inc | S-2A | Airworthiness Directives; Pitts S-2A Airplanes |
Unsafe Condition
Failure of the induction air box flapper door due to cracks in the welded areas could cause power loss.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install stiffener (Pitts Part Number 2-7112-16) to the induction air box flapper door assembly (Pitts Part Number 2-7112-7) within 50 hours time in service after the effective date. Until the modification is done, visually check for cracks every 5 hours time in service. If cracks are found, remove the flapper door and install the stiffener before further flight.
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Compliance Time
Within the next 50 hours time in service after the effective date of this airworthiness directive
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Affected Aircraft
Aviat Aircraft Inc S-2A airplanes, Serial Numbers 2001 through 2059 certificated in all categories.
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Federal Register Abstract
Induction Air Box Flapper Door
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_73-16-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-16-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Pitts S-2A Airplanes Subject: Induction Air Box Flapper Door Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/13/1973 Make: Aviat Aircraft Inc Model: S-2A Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-16-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1699 AD NUMBER: 73-16-06 SUBJECT HEADING: Airworthiness Directives; Pitts S-2A Airplanes ACTION: SUMMARY: DATES: Effective August 13, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-16-06 PITTS: Amdt. 39-1699. Applies to S-2A airplanes, Serial Numbers 2001 through 2059 certificated in all categories. Compliance required as indicated. To prevent the possibility of a power loss due to the failure of the induction air box flapper door, accomplish the following: (a) Within the next 50 hours time in service after the effective date of this airworthiness directive, unless already accomplished, install stiffener, Pitts Part Number 2-7112- 16, to the induction air box flapper door assembly, Pitts Part Number 2-7112-7, in accordance with Pitts Service Letter No. 2. Access to the induction air box flapper door assembly may be gained by removing the lower engine cowl. (b) Until the modification specified in paragraph (a) above has been accomplished, visually check the induction air box flapper assembly, Pitts Part Number 2-7112-7, for cracks in the welded areas upon the accumulation of 50 hours time in service or within 5 hours time in service, whichever is later, and thereafter at intervals not to exceed 5 hours time in service from the last check. The checks required by this AD may be performed by the pilot. If the flapper door in the area of the weld is found to be cracked, remove the flapper door assembly from the alternate air box, and add stiffener, Pitts Part Number 2-7112-16 in accordance with Pitts Service Letter No. 2, before further flight. (c) The installation of the stiffener, Pitts Part Number 2-7112-16, in accordance with Pitts Service Letter No. 2, will eliminate the necessity for the repetitive inspections required in paragraph (b). Pitts Service Letter No. 2, dated June 26, 1973, pertains to this subject. This amendment becomes effective August 13, 1973. FOOTER:
Document Text
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AD Final Rules - DRS_73-16-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-16-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Pitts S-2A Airplanes Subject: Induction Air Box Flapper Door Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/13/1973 Make: Aviat Aircraft Inc Model: S-2A 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 73-16-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1699 AD NUMBER: 73-16-06 SUBJECT HEADING: Airworthiness Directives; Pitts S-2A Airplanes ACTION: SUMMARY: DATES: Effective August 13, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-16-06 PITTS: Amdt. 39-1699. Applies to S-2A airplanes, Serial Numbers 2001 through 2059 certificated in all categories. Compliance required as indicated. To prevent the possibility of a power loss due to the failure of the induction air box flapper door, accomplish the following: (a) Within the next 50 hours time in service after the effective date of this airworthiness directive, unless already accomplished, install stiffener, Pitts Part Number 2-7112- 16, to the induction air box flapper door assembly, Pitts Part Number 2-7112-7, in accordance with Pitts Service Letter No. 2. Access to the induction air box flapper door assembly may be gained by removing the lower engine cowl. (b) Until the modification specified in paragraph (a) above has been accomplished, visually check the induction air box flapper assembly, Pitts Part Number 2-7112-7, for cracks in the welded areas upon the accumulation of 50 hours time in service or within 5 hours time in service, whichever is later, and thereafter at intervals not to exceed 5 hours time in service from the last check. The checks required by this AD may be performed by the pilot. If the flapper door in the area of the weld is found to be cracked, remove the flapper door assembly from the alternate air box, and add stiffener, Pitts Part Number 2-7112-16 in accordance with Pitts Service Letter No. 2, before further flight. (c) The installation of the stiffener, Pitts Part Number 2-7112-16, in accordance with Pitts Service Letter No. 2, will eliminate the necessity for the repetitive inspections required in paragraph (b). Pitts Service Letter No. 2, dated June 26, 1973, pertains to this subject. This amendment becomes effective August 13, 1973. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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