AD 96-03-12

This amendment adopts a new airworthiness directive (AD) that applies to Glasflugel Model Mosquito sailplanes. This action requires modifying the mounting studs on the lifting/tilting frame of the canopy system, repetitively inspecting the mounting stud, and incorporating flight manual revisions that specify a warning on emergency canopy deployment failure. Canopy system problems discovered during routine checks and periodic inspections of these sailplanes prompted the proposed action. The actions specified in this proposed AD are intended to prevent canopy system failure, which could result in loss of control of the sailplane.

Final rule

96-03-12 GLASFLUGEL: Amendment 39-9509; Docket No. 93-CE-02-AD.
Applicability: Model Mosquito Sailplanes (all serial numbers), certificated in any category.

NOTE 1: This AD applies to each sailplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For sailplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (f) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification,alteration, or repair remove any sailplane from the applicability of this AD.

Compliance: Required as indicated in the body of this AD.

To prevent canopy system failure, which could result in loss of control of the sailplane, accomplish the following:

(a) Within the next 30 calendar days after the effective date of this AD, unless already accomplished, and thereafter at the intervals not to exceed 100 hours time-in-service (TIS), inspect the mounting studs on the canopy lifting/tilting frame for evidence of wear and diameter specifications in accordance with the Actions section in Glasflugel Technical Note (TN) 303-18, dated March 1, 1991.

(b) If during any of the inspections required by paragraph (a) of this AD, the mounting stud is found worn or the diameter measures less than 5 mm (0.2 inch), prior to further flight, increase the diameter to 6 mm (0.24 inch) in accordance with paragraph 1 of the Actions section in Glasflugel TN 303-18, dated March 1, 1991.

(c) Within the next 30 calendar days after the effective date of this AD, unless already accomplished, incorporate the following language on page 19, paragraph 3.3 of the Mosquito flight manual:

"Whenever the canopy emergency jettison knob is pulled and prior to each flight, if no locking thread is used, it should be ensured that the Pip pins are fully pushed home, so that the locking balls are clear of and behind their fittings."

(d) Incorporating the flight manual revision as required by paragraph (c) of this AD may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the sailplane's records showing compliance with this AD in accordance with section 43.11 of the Federal Aviation Regulations (14 CFR 43.11).

(e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and21.199) to operate the sailplane to a location where the requirements of this AD can be accomplished.

(f) An alternative method of compliance or adjustment of the compliance times that provides an equivalent level of safety, may be approved by the Manager, Small Airplane Directorate, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate.

(g) The inspections, modifications, and installations required by this AD shall be done in accordance with Glasflugel Technical Note 303-18, dated March 1, 1991, and Glasflugel Technical Note 303-9, dated June 22, 1979. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Glasflugel c/o Hansjorg Streifeneder, Glasfaser-Flugzeug Service, Hofener Weg, D 72582 Grabenstetten, Germany, telephone number 49.73.82.10.32. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., 7th Floor, suite 700, Washington, DC.

(h) This amendment becomes effective on April 1, 1996.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that applies to Glasflugel Model Mosquito sailplanes was published in the Federal Register on September 15, 1995 (60 FR 47899). This action proposed to require the following:

Inspecting the mounting studs on the canopy lifting/tilting frame for wear, repetitively inspecting the mounting stud every 100 hours time-in-service (TIS) thereafter,

Measuring the diameter of the mounting stud and, if it is less than 5 mm (0.2 inch) increasing the diameter to 6 mm (0.24 inch) and,

Incorporating a change to the Mosquito flight manual on page 19, paragraph 3.3 by inserting the following language:

"Whenever the canopy emergency jettison knob is pulled and prior to each flight, if no locking thread is used, it should be ensured that the Pip pins are fully pushed home, so that the locking balls are clear of and behind their fittings."

Initially, the compliance time of this AD is in calendar time instead of hours time-in-service (TIS). The average monthly usage of the affected sailplanes ranges throughout the fleet. For example, one owner may operate the sailplane 25 hours in one week, while another operator may operate the sailplane 25 hours in one year. For this reason, the FAA has determined that, in order to ensure that all of the owners/operators of the affected sailplanes initially inspect the canopy system and incorporate the flight manual revisions within a reasonable amount of time, a calendar compliance time is imposed.

Accomplishment of these actions will be in accordance with Glasflugel Technical Note (TN) 303-18, dated March 1, 1991, and Glasflugel TN 303-9, dated June 22, 1979.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed rule or the FAA's determination of the cost to the public.

After careful review of all available information related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

The FAA estimates that 40 sailplanes in the U.S. registry will be affected by this AD, that it will take approximately 2 workhours per sailplane to accomplish this action, and that the average labor rate is approximately $60 an hour. Parts cost approximately $10 per sailplane. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $5,200. This figure is based on the assumption that no affected owner/operator of the affected sailplanes has incorporated the modification or accomplished the inspection.

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.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under 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. A copy of the final evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption "ADDRESSES".

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.

Section 39.13 - [AMENDED]
2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: