2011-22225. Airworthiness Directives; Cessna Aircraft Company Model 680 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD would require adding diodes to the fuel cross-feed wiring, and revising the airplane flight manual to include procedures to use when the left or right generator is selected OFF. This proposed AD was prompted by a false cross-feed command to the right-hand fuel control card, due to the cross-feed inputs on the left- and right-hand fuel control cards being connected together and causing an imbalance of fuel between the left and right wing tanks. We are proposing this AD to prevent lateral imbalance of the airplane, which can be corrected by deflecting the aileron trim, but which increases the pilot's workload. Uncontrolled fuel cross-feed results in lateral imbalance that could exceed the airplane's limitation in a short period of time. Exceeding the lateral imbalance limit could result in reduced control of the airplane.

DATES:

We must receive comments on this proposed AD by October 17, 2011.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Cessna Aircraft Co., P.O. Box 7706, Wichita, Kansas 67277; telephone [phone]; fax [phone]; e-mail [e-mail]; Internet https://www.cessnasupport.com/​newlogin.html. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Nhien Hoang, Aerospace Engineer, Electrical Systems and Avionics Branch, ACE-119W, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; phone: [phone]; fax: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2011-0913; Directorate Identifier 2011-NM-031-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

We received a report that a Model 680 airplane in flight displayed a DC EMER BUS L amber crew alerting system (CAS) message. Per the emergency/abnormal procedures checklist, the flightcrew identified a fault on the left main electrical bus and selected the left generator to OFF.

The co-pilot (flying the airplane due to the pilot's primary flight display being disabled by the left generator OFF, which also disabled the left fuel quantity indication) observed that an increasing amount of right aileron control input was required to maintain a wings-level attitude.

After the airplane safely landed, investigation showed that the left tank had 5,500 pounds of fuel (full) and the right tank 3,300 pounds. The flightcrew confirmed it had not selected the fuel cross-feed during flight. During the 20 minutes that elapsed between selecting the left generator OFF and landing, sufficient fuel had migrated from the right to the left tank creating an imbalance of 2,200 pounds. The maximum permissible fuel imbalance for this airplane is 400 pounds.

Loss of power on the left main electrical bus results in a false cross-feed command to the right-hand fuel control card, due to the cross-feed inputs on the left- and right-hand fuel control cards being connected together, thereby causing an imbalance of fuel between the left and right wing tanks. This condition, if not corrected, could result in lateral imbalance of the airplane, which can be corrected by deflecting the aileron trim, but which increases the pilot's workload. Uncontrolled fuel cross-feed results in lateral imbalance that will exceed the airplane's limitation in a short period of time. Exceeding the lateral imbalance limit could result in reduced control of the airplane.

Relevant Service Information

We reviewed Cessna Service Bulletin SB680-24-11, including Service Bulletin Supplemental Data, dated December 16, 2010, which describes procedures for adding diodes to the fuel cross-feed wiring. We have also reviewed Cessna Temporary FAA Approved Airplane Flight Manual Change 68FM TC-R09-13, dated October 15, 2010, to the Cessna 680 Citation Sovereign Airplane Flight Manual, which introduces procedures to use when the left or right generator is selected OFF.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of this same type design.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD affects 198 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Installation	4 work-hours × $85 per hour = $340	$40	$380	$75,240

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 determined that this proposed AD would not have federalism implications under Executive Order 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 this 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• 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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

Cessna Aircraft Company: Docket No. FAA-2011-0913; Directorate Identifier 2011-NM-031-AD.

Comments Due Date

(a) We must receive comments by October 17, 2011.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Cessna Aircraft Company Model 680 airplanes, certificated in any category, serial numbers -0001 through -0289 inclusive, and -0291 through -0296 inclusive.

Subject

(d) Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 24: Electrical power.

Unsafe Condition

(e) This AD was prompted by a false cross-feed command to the right-hand fuel control card, due to the cross-feed inputs on the left- and right-hand fuel control cards being connected together and causing an imbalance of fuel between the left and right wing tanks. We are issuing this AD to prevent lateral imbalance of the airplane, which can be corrected by deflecting the aileron trim, but which increases the pilot's workload. Uncontrolled fuel cross-feed results in lateral imbalance that could exceed the airplane's limitation in a short period of time and result in reduced controllability of the airplane.

Compliance

(f) Comply with this AD within the compliance times specified, unless already done.

Installation

(g) Within 400 flight hours or 12 months after the effective date of this AD, whichever occurs first: Install a kit, part number (P/N) SB680-24-11, to the left and right motive flow relays, in accordance with the Accomplishment Instructions of Cessna Service Bulletin SB680-24-11, dated December 16, 2010. The kit (P/N SB680-24-11) contains 2 sleeves, 4 splices, 2 diodes (P/N 1N4006), and instructions.

(h) Before further flight after accomplishing the actions required by paragraph (g) of this AD: Revise the Cessna 680 Citation Sovereign Airplane Flight Manual (AFM) to include the information in Cessna Temporary FAA Approved Airplane Flight Manual Change 68FM TC-R09-13, dated October 15, 2010, and remove the Temporary Changes (TCs) identified in table 1 of this AD. Cessna Temporary FAA Approved Airplane Flight Manual Change 68FM TC-R09-13, dated October 15, 2010, introduces procedures to use when the left or right generator is selected OFF. Operate the airplane according to the procedures in Cessna Temporary FAA Approved Airplane Flight Manual Change 68FM TC-R09-13, dated October 15, 2010.

Table 1—TCs To Remove From the Cessna 680 AFM

Cessna TCs—	Dated—
68FM TC-R09-09	October 15, 2010.
68FM TC-R09-10	October 15, 2010.
68FM TC-R09-11	October 15, 2010.
68FM TC-R09-12	October 15, 2010.

Note 1:

Updating the Cessna 680 Citation Sovereign AFM may be done by inserting a copy of Cessna Temporary FAA Approved Airplane Flight Manual Change 68FM TC-R09-13, dated October 15, 2010, into the AFM. When this TC has been included in general revisions of the AFM, the general revisions may be inserted in the AFM, provided the relevant information in the general revision is identical to that in Cessna Temporary FAA Approved Airplane Flight Manual Change 68FM TC-R09-13, and this TC may be removed.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Wichita Aircraft Certification Office (ACO), ACE-115W, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

Related Information

(j) For more information about this AD, contact Nhien Hoang, Aerospace Engineer, Electrical Systems and Avionics Branch, ACE-119W, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; phone: [phone]; fax: [phone]; e-mail: [e-mail].

(k) For service information identified in this AD, contact Cessna Aircraft Co., P.O. Box 7706, Wichita, Kansas 67277; telephone [phone]; fax [phone]; e mail [e-mail]; Internet https://www.cessnasupport.com/​newlogin.html. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Issued in Renton, Washington, on August 25, 2011.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.