Discussion
What events have caused this AD? The General Inspectorate of Civil Aviation (GICA), which is the airworthiness authority for Poland, recently notified FAA that an unsafe condition may exist on all PZL- Bielsko Model SZD-50-3 ``Puchacz'' sailplanes. The GICA reports that cracks were detected in the front bracket console mounted on the fuselage front bulkhead.
What is the potential impact if FAA took no action? This condition, if not detected and corrected, could cause the fuselage front bulkhead to fail. Failure of the fuselage front bulkhead could result in loss of control of the sailplane.
Has FAA taken any action to this point? We issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to all PZL-Bielsko Model SZD-50-3 ``Puchacz'' sailplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on April 21, 2004 (69 FR 21444). The NPRM proposed to require you to repetitively inspect the front and back of the fuselage front bulkhead attachment fitting for cracks, and replace any cracked attachment fitting found.
Is there a modification I can incorporate instead of repetitively inspecting the front and back of the fuselage front bulkhead attachment fitting for cracks? The FAA has determined that long-term continued operational safety would be better assured by design changes that remove the source of the problem rather than by repetitive inspections or other special procedures. With this in mind, FAA will continue to work with PZL-Bielsko in performing further tests to determine the cause of the cracking and to provide a corrective action that would terminate the need for repetitive inspections.
What is the difference between this AD and the service information? The manufacturer's service information
allows continued flight if cracks are found in the fuselage front bulkhead attachment fittingthat do not exceed certain limits. The applicable service bulletin specifies replacement of the fuselage front bulkhead attachment fitting only if cracks are found exceeding this limit. This AD will not allow continued flight if any crack is found. FAA policy is to disallow sailplane operation when known cracks exist in primary structure, unless the ability to sustain ultimate load with these cracks is proven. The fuselage front bulkhead is considered primary structure, and the FAA has not received any analysis to prove that ultimate load can be sustained with cracks in this area.
Comments
Was the public invited to comment? We provided the public the opportunity to participate in developing this AD. We received no comments on the proposal or on the determination of the cost to the public.
Conclusion
What is FAA's final determination on this issue? We have carefully reviewed the available data and determined that air safety and the public interest require adopting theAD as proposed except for minor editorial corrections. We have determined that these minor corrections:
--Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
--Do not add any additional burden upon the public than was already proposed in the NPRM.
Changes to 14 CFR Part 39--Effect on the AD
How does the revision to 14 CFR part 39 affect this AD? On July 10, 2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's AD system. This regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.
Costs of Compliance
How many sailplanes does this AD impact? We estimate that this AD affects 8 sailplanes in the U.S. registry.
What is the cost impact of this AD on owners/operators of the affected sailplanes? We estimate the following costs to accomplish the inspection:
Labor cost
Parts cost
Total cost per sailplane
Total cost on U.S. operators
2 workhours x $65 per hour = $130
Not applicable
$130
$130 x 8 = $1,040.
We estimate the following costs to accomplish any necessary replacement that will be required based on the results of this inspection. We have no way of determining the number of sailplanes that may need such a replacement:
Labor cost
Parts cost
Total cost per sailplane
10 workhours x $65 per hour = $650
$680
$650 + $680 = $1,330.
Regulatory Findings
Will this AD impact various entities? We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect 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.
Will this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order 12866;
2. Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and
3. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include ``AD Docket No. 2003-CE-68-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under 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. FAA amends 39.13 by adding a new AD to read as follows: