# Airworthiness Directives; Gulfstream Model G-IV 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 Gulfstream Model G-IV series airplanes. That action would have required inspection of the data plate on the bottom of the hydraulic brake control module (HBCM) to verify the part and serial numbers, and replacement of the HBCM, if necessary. Since the issuance of the NPRM, the Federal Aviation Administration (FAA) has received new data indicating that the proposed actions have been accomplished on all affected airplanes; therefore, the previously identified unsafe condition no longer exists. Accordingly, the proposed rule is withdrawn.
**FOR FURTHER INFORMATION CONTACT:**
Neil Barryman, Aerospace Engineer, Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone (770) 703-6098; fax (770) 703-6097.
**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 Gulfstream Model G-IV series airplanes, was published in the *Federal Register* as a Notice of Proposed Rulemaking (NPRM) on April 9, 1993 (58 FR 18347). The proposed rule would have required inspection of the data plate on the bottom of the hydraulic brake control module (HBCM) to verify the part and serial numbers, and replacement of the HBCM, if necessary. That action was prompted by a landing incident that involved a malfunction of the braking system. The proposed actions were intended to prevent a malfunction of the braking system, which could lead to reduced controllability of the airplane on the ground.
**Actions that Occurred Since the NPRM Was Issued**
Since the issuance of that NPRM, Gulfstream has provided evidence to the FAA that the actions proposed in the NPRM have been accomplished on all affected airplanes (Evidence was provided to the FAA in Gulfstream's letter of May 30, 2000, which is filed in the Rules Docket.)
**FAA's Conclusions**
Upon further consideration, the FAA has determined that, based on this evidence, the previously identified unsafe condition no longer exists with regard to the Gulfstream Model G-IV series airplanes. Accordingly, the proposed rule is hereby withdrawn.
Withdrawal of this notice of proposed rulemaking constitutes only such action, and does not preclude the agency from issuing another notice 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 notice of proposed rulemaking, Docket 92-NM-206-AD, published in the *Federal Register* on April 9, 1993 (58 FR 18347), is withdrawn.
Issued in Renton, Washington, on June 7, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.