Discussion
The FAA has received information from an inspection of a Cessna Model 206H airplane that reveals that the aileron control bellcrank stop bolt had partially backed out of the threaded boss on one end of a yoke assembly. This restricted the movement of both ailerons, which could result in partial or complete loss of aileron control.
Both the Cessna Models 206H and T206H airplanes with the following serial numbers have aileron system designs where the above-referenced situation could exist:
Models
Serial Numbers
206H
20608002 through 20608026
T206H
T20608002 through T20608015; T20608017 through T20608023; and T20608025 through T20608028
Relevant Service Information
Cessna has issued Special Service Project SSP99-27-02, which specifies procedures for inspecting the left and right wing aileron control bellcrank stop bolts and lock nuts for flush and tight contact with the surface of the threaded boss on each end of the yoke assemblies, and accomplishing follow-on and corrective actions, as applicable.
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:
- the actions referenced in the service information should be accomplished on the Cessna Models 206H and T206H airplanes; and
- AD action should be taken to detect and correct loose aileron control bellcrank stop bolts, which could result in restricted movement of the aileron with possible partial or complete loss of aileron control.
Explanation of the Provisions of the AD
Since an unsafe condition has been identified that is likely to exist or develop in other Cessna Models 206H and T206H airplanes of the same type design, the FAA is taking AD action. This AD requires inspecting the left and right wing aileron control bellcrank stop bolts and lock nuts for flush and tight contact with the surface of the threaded boss on each end of the yoke assemblies, and accomplishing follow-on and corrective actions, as applicable.
Accomplishment of the actions specified in this AD are required in accordance with the instructions in Cessna Special Service Project SSP99-27-02, dated May 18, 1999.
Compliance Time of This AD
Although the aileron control bellcrank stop bolts and lock nuts not being flush and in tight contact with the surface of the threaded boss on each end of the yoke assemblies is only unsafe while the airplane is in flight, this condition is not a result of the number of times the airplane is operated. The chance of this situation existing is the same for an airplane with 200 hours time-in-service (TIS) as it is for an airplane with 3,000 hours TIS. In addition, the usage levels of the affected airplane vary immensely. Some operators may accumulate 25 hours TIS in a matter of days, where other operators may only utilize their airplanes a few hours ina month.
For these reasons, the FAA has determined that a compliance based on calendar time and hours TIS (with the prevalent one being that which occurs first) should be utilized in this AD in order to assure that the unsafe condition is addressed on all affected airplanes in a reasonable time period without inadvertently grounding certain airplanes. The compliance time of the inspection required by this AD will be as follows:
"Within the next 10 hours TIS after the effective date of this AD or within the next 60 calendar days after the effective date of this AD, whichever occurs first."
Determination of the Effective Date of the AD
Since a situation exists (possible partial or complete loss of aileron control) 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
Althoughthis 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 energy aspects 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. 99-CE-23-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, Incorporation by reference, 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 U.S.C. 106(g), 40113, 44701.
39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: