E8-1706. Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-120 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Proposed rule; withdrawal.

SUMMARY:

This action withdraws a notice of proposed rulemaking (NPRM) that proposed a new airworthiness directive (AD), applicable to certain EMBRAER Model EMB-120 series airplanes. That action would have required repetitive calibration testing of potentiometers to detect noisy signals, replacement of only those with noisy signals, and reporting results of the calibration tests of the potentiometers and the readouts of the flight data recorder (FDR) to the airplane manufacturer. Since the issuance of the NPRM, the Federal Aviation Administration (FAA) has determined that while a noisy or defective potentiometer may hamper the ability to access certain aircraft data in support of either an accident or incident investigation or just general maintenance activities, there is no direct effect on the aircraft's ability to be operated safely. Accordingly, the proposed rule is withdrawn.

FOR FURTHER INFORMATION CONTACT:

Todd Thompson, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add a new airworthiness directive (AD), applicable to certain EMBRAER Model EMB-120 series airplanes, was published in the Federal Register as a second supplemental Notice of Proposed Rulemaking (NPRM) on February 1, 2005 (70 FR 5070). The proposed rule would have required repetitive calibration testing of potentiometers to detect noisy signals, replacement of only those with noisy signals, and reporting results of the calibration tests of the potentiometers and the readouts of the flight data recorder (FDR) to the airplane manufacturer. The proposed actions were intended to prevent the potentiometers that provide information on the positions of the primary flight controls to the FDR from transmitting noisy signals or becoming improperly calibrated, resulting in the transmission of incomplete or inaccurate data to the FDR.

Actions That Occurred Since the Second Supplemental NPRM Was Issued

Since the issuance of the second supplemental NPRM, the FAA has determined that while a noisy or defective potentiometer may hamper the ability to access certain aircraft data in support of either an accident or incident investigation or just general maintenance activities, there is no direct effect on the aircraft's ability to be operated safely.

On December 7, 2007, we issued Special Airworthiness Information Bulletin (SAIB) NM-08/10 to recommend calibrating, testing, and replacing certain potentiometers to the ailerons, elevators, and rudder of the subject airplanes, which is part of the manufacturer's recommended maintenance program.

FAA's Conclusions

Upon further consideration, the FAA has determined that no unsafe condition exists. Accordingly, the proposed rule is hereby withdrawn.

Withdrawal of this second supplemental NPRM constitutes only such action, and does not preclude the agency from issuing another action in the future, nor does it commit the agency to any course of action in the future.

Regulatory Impact

Since this action only withdraws a notice of proposed rulemaking, it is neither a proposed nor a final rule and therefore is not covered under Executive Order 12866, the Regulatory Flexibility Act, or DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979).

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Withdrawal

Accordingly, the second supplemental notice of proposed rulemaking, Directorate Identifier 2000-NM-120-AD, published in the Federal Register on February 1, 2005 (70 FR 5070), is withdrawn.

Issued in Renton, Washington, on January 15, 2008.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.