Discussion
Puritan-Bennett recently notified the FAA of a quality control problem on cone and seal assemblies, part numbers 210543 and 210543-01, that were manufactured or repaired from August 1996 through July 1997. Quality control sampling indicates that approximately 10-percent of the cone and seal assemblies manufactured or repaired during this time have ultrasonic welds that could fail. The FAA has no way of determining which particular cone and seal assemblies may have ultrasonic welds that could fail.
These Puritan-Bennett cone and seal assemblies, part numbers 210543 and 210543-01, may be attached to the following part number Puritan-Bennett sweep-on crew oxygen masks:
114321-01 114321-15 114321-16 114322-01
114322-02 114322-03 114322-05 114323-01
114622-01 114622-02 114623-01 114623-02
If the affected cone and seal assemblies that have ultrasonic welds that could fail are not identified and replaced, then the oxygen flow through the crew masks could be reduced, which could result in the crew not being able to obtain oxygen in an emergency situation.
Relevant Service Information
Puritan-Bennett has issued Service Bulletin No. 3500-97-14, dated August 7, 1997. This service bulletin specifies identification and replacement of these part numbers 210543 and 210543-01 cone and seal assemblies that were manufactured or repaired from August 1996 through July 1997.
The FAA's Determination
After examining the circumstances and reviewing all available information related to the incidents described above, including the relevant service information, the FAA has determined that AD action should be taken to prevent reduced oxygen flow through the crew mask, which could result in the crew not being able to obtain oxygen in an emergency situation.
Explanation of the Provisions of the AD
Since an unsafe condition has been identified that is likely to exist or develop in aircraft that have these part numbers 210543 and 210543-01 Puritan-Bennett cone and seal assemblies installed, the FAA is issuing an AD. This AD requires replacing any of these cone and seal assemblies that were manufactured or repaired from August 1996 through July 1997.
Compliance Time of This AD
The condition specified by this AD is not caused by actual hours time-in-service (TIS) of the aircraft where the affected Puritan-Bennett cone and seal assemblies are installed. The need for the replacement has no correlation to the number of times the equipment is utilized or the age of the equipment. For this reason, the compliance time of this AD is presented in calendar time instead of hours TIS.
Determination of the Effective Date of the AD
Since a situation exists (reduced oxygen flow to the crew in an emergency situation) that requires the immediate adoption of this regulation, it is found that notice and opportunity for public prior comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves requirements affecting immediate flight safety and, thus, was not preceded by notice and opportunity to comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.
Comments are specifically invited on the overall regulatory, economic, environmental, and energyaspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket No. 97-CE-75-AD." The postcard will be date stamped and returned to the commenter.
Regulatory Impact
The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a significant regulatory action under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket (otherwise, an evaluation is not required). A copy of it, if filed, may be obtained from the Rules Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39 - AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 USC 106(g), 40113, 44701.
39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: