Airworthiness directives: Gulfstream,
[Federal Register: August 8, 2005 (Volume 70, Number 151)]
[Proposed Rules]
[Page 45581-45585]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08au05-22]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
[Docket No. FAA-2005-22034; Directorate Identifier 2004-NM-182-AD]
RIN 2120-AA64
Airworthiness Directives; Gulfstream Model GV and GV-SP Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for all Gulfstream Model GV and certain Model GV-SP series airplanes. This proposed AD would require a one-time inspection of the left and right aileron and elevator actuators to determine the part and serial numbers of each actuator, repetitive inspections of suspect actuators to detect broken damper shafts, and replacement of any actuator having a broken damper shaft. This proposed AD would also require that operators report any broken damper shaft they find to the FAA. This proposed AD also would provide an optional terminating action for the repetitive inspection requirements of this proposed AD. This proposed AD is prompted by reports of broken or cracked damper shafts within the aileron and elevator actuator assemblies. We are proposing this AD to detect and correct broken damper shafts, which could result in locking of an aileron or elevator actuator (hard-over condition), which would activate the hard-over protection system (HOPS), resulting in increased pilot workload and consequent reduced controllability of the airplane.
DATES: We must receive comments on this proposed AD by September 22, 2005.
ADDRESSES: Use one of the following addresses to submit comments on this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide Rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, Washington, DC 20590.
By Fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, Georgia 31402-9980.
You can examine the contents of this AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility,
U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC. This docket number is FAA-2005-22034; the directorate identifier for this docket is 2004-NM-182-AD.
FOR FURTHER INFORMATION CONTACT: Gerald Avella, Aerospace Engineer, Systems and Equipment Branch, ACE-119A, FAA, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone (770) 703-6066; fax (770) 703- 6097.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed under ADDRESSES. Include ``Docket No. FAA-2005-22034; Directorate Identifier 2004-NM-182-AD'' in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments submitted by the closing date and may amend the proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov , including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You can review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.
Examining the Docket
You can examine the AD docket on the Internet at http://dms.dot.gov , or in
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person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System (DMS) receives them.
Discussion
We have received a report from the airplane manufacturer, Gulfstream, indicating that the damper shafts in two actuators broke under normal torquing requirements during assembly of the actuators for a Gulfstream Model GV-SP airplane. Approximately one week after the original occurrence, a third actuator was found with a cracked damper shaft. In each case, the cracks originated at the threaded base of the damper shaft. In addition, the third actuator was found to be from a manufacturing lot previous to that of the other two actuators. Parker Aerospace, the actuator manufacturer, notified Gulfstream that the production process used after 1998 to manufacture aileron and elevator actuator damper shafts (internal to the actuator) may induce cracks in the threaded portion of the shaft. This cracking could cause the retaining nut and the separated portion of the failed damper shaft to become dislodged from the damper body and block the movement of the assembly. This condition, if not corrected, could result in locking of an aileron or elevator actuator (hard-over condition), which would activate the hard-over protection system (HOPS), resulting in increased pilot workload and consequent reduced controllability of the airplane.
The affected aileron and elevator actuators installed on Gulfstream Model GV and GV-SP series airplanes are identical to those installed on Model G-1159, G-1159A, G-1159B, and G-IV series airplanes. Therefore, all of these models may be subject to the identified unsafe condition.
Other Rulemaking for Additional Airplane Models
On October 4, 2004, we issued AD 2004-21-03, amendment 39-13824 (69 FR 61305, October 18, 2004), applicable to all Gulfstream Model G-1159, G-1159A, G-1159B, and G-IV series airplanes. That AD currently requires a one-time inspection of the left and right aileron and elevator actuators to determine the part and serial numbers of each actuator, repetitive inspections of suspect actuators to detect broken damper shafts, and replacement of any actuator having a broken damper shaft. That AD also requires that operators report any broken damper shaft(s) they find to the FAA. That AD also provides an optional terminating action for the repetitive inspection requirements of that AD. That AD was prompted by reports of broken or cracked damper shafts within the aileron and elevator actuator assemblies. The actions required by that AD are intended to detect and correct broken damper shafts, which could result in locking of an aileron or elevator actuator (hard-over condition), subsequent loss of aileron or elevator control, and consequent reduced controllability of the airplane.
Relevant Service Information
We have reviewed the following Gulfstream customer bulletins:
Table.--Relevant Service Information
Model
Customer bulletin
Dated
1. GV and GV-SP series airplanes Gulfstream G500 August 23, 2004. Customer Bulletin 4. 2. GV and GV-SP series airplanes Gulfstream G550 August 23, 2004. Customer Bulletin 4. 3. GV and GV-SP series airplanes Gulfstream GV August 23, 2004. Customer Bulletin 123.
The customer bulletins describe procedures for a one-time inspection of the left and right aileron and elevator actuators to determine the part number (P/N) and serial number (S/N) of each actuator. The customer bulletins also describe procedures for an inspection of the actuators with certain P/Ns and S/Ns to detect broken damper shafts, and replacement of any actuator having a broken damper shaft with a new or serviceable actuator.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. Therefore, we are proposing this AD, which would require:
1. A one-time inspection of the left and right aileron and elevator actuators to determine the part and serial numbers of each actuator;
2. Repetitive inspections of suspect actuators to detect broken damper shafts, and replacement of any actuator having a broken damper shaft; and
3. Any broken damper shaft found during the initial and repetitive inspections is to be reported to the FAA. These actions are to be done in accordance with the service information described previously, except as discussed under ``Differences Between the Proposed AD and Customer Bulletins.''
We are not proposing to require the terminating action (i.e., replacement of all suspect actuators) at this time, because we have determined, and the actuator manufacturer has confirmed, that the necessary replacement actuators (with a P/N and/or S/N not listed in the applicable customer bulletin) are not yet available and will not be available for another 24 to 36 months. Therefore, we are providing the terminating action as an option for operators once those parts become available.
Differences Between the Proposed AD and Customer Bulletins
The customer bulletins do not specify what to do if an installed actuator has either a P/N or S/N that is missing or is unreadable. This proposed AD would require that those actuators also be inspected to detect broken damper shafts--as if they have a P/N and S/N listed in the customer bulletins.
The customer bulletins recommend a one-time inspection of the aileron and elevator actuators for broken damper shafts. However, a suspect damper shaft found undamaged during the initial inspection still has the potential to break at some time in the future. Because a one-time inspection alone would not provide the degree of safety necessary, we have determined that repetitive inspections of the suspect actuators are necessary to ensure an adequate level of safety for the affected transport airplane fleet. We have also determined that an interval of 500 flight hours is an appropriate compliance time for the repetitive inspections. Although the customer bulletins do not include
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repetitive inspections, they do note that a recurring inspection will be added to the applicable airplane maintenance manual.
The customer bulletins also do not specify the type of inspection to use to detect broken damper shafts. We have determined that a detailed inspection for this action is appropriate. Therefore, this proposed AD would require a detailed inspection to detect broken damper shafts, and we have included the definition of a detailed inspection in this proposed AD.
The customer bulletins specify replacing an actuator having a broken damper shaft, but they do not specify the type of replacement actuator. This proposed AD would require replacement with either:
A new or serviceable actuator having a subject P/N and S/N listed in the customer bulletin, provided the actuator has been and continues to be inspected for broken damper shafts in accordance with the requirements of this proposed AD; or
A new or serviceable actuator having a P/N and/or S/N different from any listed in the customer bulletin. Replacing an actuator with an actuator having a different P/N and/or S/N would terminate the requirements of this proposed AD for that actuator only.
The customer bulletins do not specify reporting findings of broken damper shafts. This proposed AD would require that findings of all broken damper shafts be reported to the FAA. When the unsafe condition addressed by an AD is likely due to a manufacturer's quality control (QC) problem, a reporting requirement is instrumental in ensuring that we can gather as much information as possible regarding the extent and nature of the QC problem or breakdown, especially in cases where the data may not be available through other established means. This information is necessary to ensure that proper corrective action will be taken. Based on the results of these reports, we may determine that further corrective action is warranted.
The Accomplishment Instructions of the customer bulletins specify to submit the Service Reply Card or compliance information to the manufacturer. This proposed AD does not include those actions.
These differences have been coordinated with the airplane manufacturer.
Clarification of Applicability
The effectivities of the customer bulletins include all Model GV and certain Model GV-SP series airplanes, equipped with aileron or elevator actuators having certain P/Ns and S/Ns. Because there is no way to determine if an actuator with a suspect P/N and S/N is installed without inspecting the airplane, this proposed AD would apply to all Model GV series airplanes and Model GV-SP series airplanes having certain S/Ns. This requirement would ensure that the actions specified in the service bulletins and required by this proposed AD are accomplished on all affected airplanes. Note that the first action in the customer bulletins is an inspection to determine if an actuator having a certain P/N and S/N is installed.
Interim Action
This proposed AD is considered to be interim action. The inspection reports that are required by this proposed AD will enable us to work with the manufacturer to obtain better insight into the nature and extent of the broken damper shafts, and eventually to develop final action to address the unsafe condition. Once final action has been developed and replacement parts are available, we may consider further rulemaking.
Changes to 14 CFR Part 39/Effect on the AD Relating to Special Flight Permits
On July 10, 2002, the FAA issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance (AMOC). This material is included in part 39, except that the office authorized to approve AMOCs is identified in each individual AD. However, as amended, part 39 provides for the FAA to add special requirements for operating an airplane to a repair facility to do the work required by an airworthiness directive. For the purposes of this proposed AD, we have determined that such a special flight permit would be prohibited if a broken damper shaft is found during the inspection of the subject aileron and elevator actuators provided by paragraph (i) of this proposed AD. Locking of an aileron or elevator actuator, which would activate the hard-over protection system (HOPS), would significantly reduce controllability of the airplane and increase pilot workload. Intentionally operating an airplane in this condition would inherently increase the risk of a major event.
Costs of Compliance
There are about 214 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 174 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.
Estimated Costs
Work Average labor
Cost per Action
hours rate per hour Parts airplane
Fleet cost
Inspection for part/serial number....
1
$65 $0
$65 $11,310. Inspection of actuators, per
2
65
0
130 $22,620, per inspection inspection cycle (if required).
cycle.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in subtitle VII, part A, subpart III, section 44701, ``General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.
Regulatory Findings
We have determined that this proposed AD would not have federalism implications under Executive Order
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13132. This proposed AD would 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.
For the reasons discussed above, I certify that the proposed regulation:
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 regulatory evaluation of the estimated costs to comply with this proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):
Gulfstream Aerospace Corporation: Docket No. FAA-2005-22034; Directorate Identifier 2004-NM-182-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by September 22, 2005.
Affected ADs
(b) None.
Applicability: (c) This AD applies to all Gulfstream Model GV series airplanes, and Model GV-SP series airplanes having serial numbers (S/Ns) 5001 through 5052 inclusive; certificated in any category.
Unsafe Condition
(d) This AD was prompted by reports of broken or cracked damper shafts within the aileron and elevator actuator assemblies. We are issuing this AD to detect and correct broken damper shafts, which could result in locking of an aileron or elevator actuator (hard- over condition), which would activate the hard-over protection system (HOPS), resulting in increased pilot workload and consequent reduced controllability of the airplane.
Compliance: (e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Service Information References
(f) The term ``customer bulletin,'' as used in this AD, means the Accomplishment Instructions of the applicable Gulfstream customer bulletins specified in Table 1 of this AD. Although the customer bulletins recommend completing and submitting the Service Reply Card or reporting compliance with the customer bulletin, those actions are not required by this AD.
Table 1.--Applicable Gulfstream Customer Bulletins
Model
Customer bulletin
Dated
(1) GV-SP series airplanes...... Gulfstream G500 August 23, 2004. Customer Bulletin 4. (2) GV-SP series airplanes...... Gulfstream G550 August 23, 2004. Customer Bulletin 4. (3) GV series airplanes......... Gulfstream GV August 23, 2004. Customer Bulletin 123.
Inspection To Determine Actuator Part and Serial Numbers
(g) Within 500 flight hours after the effective date of this AD: Do a one-time inspection of the left and right aileron and elevator actuators to determine the part number (P/N) and S/N of each actuator, in accordance with the applicable customer bulletin.
No Subject Actuators Installed
(h) If no actuator with a P/N and S/N listed in the applicable customer bulletin is identified during the inspection required by paragraph (g) of this AD, no further action is required by this AD, except as required by paragraph (l) of this AD.
Initial and Repetitive Inspections and Corrective Action for Subject Actuators
(i) For any actuator identified during the inspection required by paragraph (g) of this AD with a P/N and S/N listed in the applicable customer bulletin, and for actuators for which the P/N or S/N is missing or unreadable: Before further flight, do a detailed inspection of each identified actuator to detect a broken damper shaft, in accordance with the applicable customer bulletin.
Note 1: For the purposes of this AD, a detailed inspection is: ``An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.''
(1) If no damper shaft is found broken: Repeat the inspection required by paragraph (i) of this AD thereafter at intervals not to exceed 500 flight hours.
(2) If any damper shaft is found broken: Before further flight, do the action specified in either paragraph (i)(2)(i) or (i)(2)(ii) of this AD, in accordance with the applicable customer bulletin.
(i) Replace the actuator with a new or serviceable actuator having a P/N and S/N listed in the applicable customer bulletin, provided the new or serviceable actuator has been inspected in accordance with the requirements of paragraph (i) of this AD. Thereafter, repeat the inspection required by paragraph (i) of this AD for that actuator at intervals not to exceed 500 flight hours.
(ii) Replace the actuator with a new or serviceable actuator having a P/N and/or S/N not listed in the applicable customer bulletin. This replacement terminates the requirements of this paragraph for that actuator only.
Optional Terminating Action
(j) Except as required by paragraph (l) of this AD, replacement of all suspect actuators with new or serviceable actuators having a P/N and/or S/N not listed in the applicable customer bulletin terminates the requirements of this AD.
Reporting Requirement
(k) Submit a report of any broken damper shafts to the Manager, Atlanta Aircraft Certification Office (ACO), FAA, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; fax (770) 703-6097. The report must be done at the applicable time specified in paragraph (k)(1) or (k)(2) of this AD. The report must include the inspection date, the airplane model and S/N, the actuator position (left or right aileron or elevator), and the actuator P/N and S/N. Information collection requirements contained in this AD have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120- 0056.
(1) If the inspection required by paragraph (i) of this AD is done after the effective date of this AD: Submit a report within 30 days after each inspection required by paragraph (i) of this AD.
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(2) If an inspection required by paragraph (i) of this AD was done before the effective date of this AD: Submit a report within 30 days after the effective date of this AD.
Parts Installation
(l) As of the effective date of this AD, no person may install an aileron or elevator actuator having a P/N and S/N specified in the applicable customer bulletin on any airplane, unless the actuator has been inspected according to paragraph (i) of this AD.
Special Flight Permit Prohibited
(m) Special flight permits (14 CFR 21.197 and 21.199) are not allowed if any broken damper shaft is found during any inspection required by paragraph (i) of this AD.
Alternative Methods of Compliance (AMOCs)
(n) The Manager, Atlanta ACO, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19..
Issued in Renton, Washington, on August 2, 2005. Kevin Mullin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 05-15589 Filed 8-5-05; 8:45 am]
BILLING CODE 4910-13-P
