Federal Aviation Administration (FAA), DOT.
Final special conditions.
These special conditions are issued for the Cessna Aircraft Company, model 525C airplane. This airplane will have a novel or unusual design feature(s) associated with a Single Point Refuel/Defuel system. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.
Effective Date: August 20, 2009.Start Further Info
FOR FURTHER INFORMATION CONTACT:
Peter L. Rouse, Federal Aviation Administration, Aircraft Certification Service, Small Airplane Directorate, ACE-111, 901 Locust, Kansas City, Missouri, 816-329-4135, fax 816-329 4090.End Further Info End Preamble Start Supplemental Information
On August 9, 2006, Cessna Aircraft Company applied for an amendment to Type Certificate Number A1WI to include the new model 525C (CJ4). The model 525C (CJ4), which is a derivative of the model 525B (CJ3) currently approved under Type Certificate Number A1WI, is a commuter category, low-winged monoplane with “T” tailed vertical and horizontal stabilizers, retractable tricycle type landing gear and twin turbofan engines mounted on the aircraft fuselage. The maximum takeoff weight is 16,650 pounds, the VMO/MMO is 305 KIAS/M 0.77 and maximum altitude is 45,000 feet.
The model 525C fuel system will incorporate a Single Point Refuel/Defuel system. The model 525C Single Point Refuel/Defuel system is used to pressure refuel and defuel the left and right wing fuel tanks from a single refuel/defuel adapter. The system is operated by fuel level and positive refuel or negative defuel pressure. This system is similar in design to other part 25 Cessna Citation airplanes and uses many of the same components that are used in these other airplanes. The components for the model 525C refuel/defuel system include a refuel/defuel adapter, a precheck valve, various other check valves, a high level pilot valve, a refuel valve, a defuel valve, and a positive/negative relief valve. Single point refueling is accomplished by connecting the refuel equipment to the refuel/defuel adapter and applying positive pressure. Fuel is directed through a common manifold to each wing tank's fuel shutoff (refuel) valve. Single point defueling is accomplished by connecting defuel equipment to the refuel/defuel adapter and applying negative pressure. Defueling is controlled by fuel level and negative pressure from the defuel equipment.
The incorporation of a pressure defueling system was not considered when 14 CFR part 23 was created and there are no applicable certification requirements for this novel and unusual design feature. Pressure defueling systems are more common on part 25 airplanes, and the applicable certification requirements are contained in 14 CFR part 25, § 25.979(e), which states: “The airplane defueling system (not including fuel tanks and fuel tank vents) must withstand an ultimate load that is 2.0 times the load arising from the maximum permissible defueling pressure (positive or negative) at the airplane fueling connection.” With the pressure defueling system design incorporated on the model 525C, it is necessary to apply a special condition to this novel and unusual design feature.
Type Certification Basis
Under the provisions of § 21.101, Cessna Aircraft Company must show that the model 525C meets the applicable provisions of the regulations incorporated by reference in Type Certificate Number A1WI or the applicable regulations in effect on the date of application for the change to the model 525B. The regulations incorporated by reference in the type certificate are commonly referred to as the “original type certification basis.” In addition, the certification basis includes exemptions, if any; equivalent level of safety findings, if any; and the special condition adopted by this rulemaking action.
If the Administrator finds that the applicable airworthiness regulations in 14 CFR part 23 do not contain adequate or appropriate safety standards for the model 525C because of a novel or unusual design feature, special conditions are prescribed under the provisions of § 21.16.
In addition to the applicable airworthiness regulations and special conditions, the model 525C must comply with the fuel vent and exhaust emission requirements of 14 CFR part 34 and the noise certification requirements of 14 CFR part 36.
Special conditions, as appropriate, as defined in § 11.19, are issued in accordance with § 11.38, and become part of the type certification basis in accordance with § 21.101.
Special conditions are initially applicable to the model for which they are issued. Should the type certificate for that model be amended later to include any other model that Start Printed Page 45101incorporates the same novel or unusual design feature, or should any other model already included on the same type certificate be modified to incorporate the same novel or unusual design feature, the special conditions would also apply to the other model under the provisions of § 21.101.
Novel or Unusual Design Features
The model 525C will incorporate the following novel or unusual design features: A single point refuel/defuel system.
Discussion of Comments
Notice of proposed special conditions No. 23-09-01-SC for the Cessna Aircraft Company, model 525C airplanes was published in the Federal Register on April 15, 2009 (74 FR 17438). No comments were received, and the special conditions are adopted as proposed.
As discussed above, these special conditions are applicable to the model 525C. Should Cessna Aircraft Company apply at a later date for a change to the type certificate to include another model incorporating the same novel or unusual design feature, the special conditions would apply to that model as well.
Under standard practice, the effective date of final special conditions would be 30 days after the date of publication in the Federal Register; however, as the certification date for the Cessna Aircraft Company, Model 525C is imminent, the FAA finds that good cause exists to make these special conditions effective upon issuance.
This action affects only certain novel or unusual design features on one model of airplane. It is not a rule of general applicability, and it affects only the applicant who applied to the FAA for approval of these features on the airplane.Start List of Subjects
List of Subjects in 14 CFR Part 23End List of Subjects
CitationStart Amendment Part
The authority citation for these special conditions is as follows:End Amendment Part
The Special Conditions
Accordingly, pursuant to the authority delegated to me by the Administrator, the following special conditions are issued as part of the type certification basis for Cessna Aircraft Company, model 525C airplanes.
The airplane defueling system (not including fuel tanks and fuel tank vents) must withstand an ultimate load that is 2.0 times the load arising from the maximum permissible defueling pressure (positive or negative) at the airplane fueling connection.Start Signature
Issued in Kansas City, Missouri, on August 20, 2009.
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. E9-21056 Filed 8-31-09; 8:45 am]
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