23.1450 Chemical oxygen generators
No policy available as of September 30, 2003.
There is no corresponding rule in CAR 3 or the Airship Design Criteria.
23.1451 Fire protection for oxygen equipment
There is no corresponding rule in CAR 3 or the Airship Design Criteria.
Amendment 23-49 and Subsequent
A proposed revision to NPRM 94-21 explains this rule as follows: “This proposed new section would specify that fire protection is needed for oxygen equipment installations. Section 23.1451(a) and (b) would, respectively, prohibit the installation of oxygen equipment in designated fire zones and require that oxygen system components be protected from the heat from designated fire zones.
Proposed Sec. 23.1451(c) would require oxygen equipment and lines to be separated from other equipment or to be protected in a manner that would prevent escaping oxygen from striking grease, fluids, or vapors. The impingement of pure oxygen on certain materials will lower their combustion point to a value where ignition will occur in ambient conditions thereby creating a potential source for an airplane fire.
In one instance, an airplane was destroyed by fire that resulted when escaping oxygen impinged on lubricating material during maintenance of the airplane. The proposed new section would ensure that oxygen systems are protected to prevent fire hazards that can result from escaping oxygen.”
23.1453 Protection of oxygen equipment from rupture
There is no corresponding rule in CAR 3 or the Airship Design Criteria.
Amendment 23-49 and Subsequent
A proposed revision to NPRM 94-21 explains this rule as follows: “This proposed new section would clarify the rupture protection needed for oxygen system installation. Rupture protection for oxygen systems is currently required by the application of the structures load requirements of part 23. The addition of Sec. 23.1453(a) would clarify the application of these load requirements and would identify the need to consider maximum temperatures and pressures that may be present. Section 23.1453(b) would identify the protection to be provided for high pressure oxygen sources and the high pressure lines that connect such sources to the oxygen system shutoff valves.”
Amendment 23-49 is clarified by Final Rule, Docket 27806, as follows: “Proposed new Sec. 23.1453 would clarify the rupture protection needed for oxygen system installation. Rupture protection for oxygen systems is currently required by the application of the structure load requirements of part 23. The addition of Sec. 23.1453(a) would clarify the application of these load requirements and would identify the need to consider maximum temperatures and pressures that may be present. Section 23.1453(b) would identify the protection to be provided for high pressure oxygen sources and the pressure lines that connect such sources to the oxygen system shutoff valves.
The comments received on this proposal from the JAA and the Civil Aviation Authority (CAA). CAA noted that the word "high" in paragraph (b) could lead to confusion and require interpretation. Accordingly, they suggested that the words "High pressure oxygen sources" be revised to read as follows: "Oxygen pressure sources." This is the same text that is used in JAR 23.
The FAA agrees with the suggested wording change. When the proposal was originally drafted, the FAA was considering the oxygen source side of the oxygen regulator, the high pressure side, and the passenger dispensing side of the regulator, the low pressure side; thus, the word "high" was used.
The suggested change will not alter the requirements applicability and will be more clearly understood. It is also noted that the suggested text change will more closely align with the same requirement in Sec. 25.1453. Section 23.1453 is changed by revising the first four words of proposed paragraph (b) to read, "Oxygen pressure sources.
This section is adopted with the above change.”
23.1457 Cockpit voice recorders
EASA AMC 23.1459(b) is acceptable for FAA certification.
There is no corresponding rule in CAR 3 or the Airship Design Criteria.
Amendment 23-35 and Subsequent
This rule is explained by Final Rule, Docket 25530, as follows: “Significant changes between the proposed rule and the final rule are summarized below. These changes were discussed in the appropriate sections of the Comment Discussion above:
(1) The compliance dates have been extended from 2 years to 3 years.
(2) Pre-wiring requirements in Sec. 91.35 and Sec. 135.52 have been deleted.
(3) The requirements for airplanes currently equipped with a digital date bus are clarified in Secs. 121.343(e) and 125.225(c).
(4) Certain of the parameters in Appendix B of Part 121 have been made optional.
(5) Aircraft required to be upgraded under Sec. 135.152(b) must meet the 11- parameter or 17-parameter flight recorder requirements (currently required of certain airplanes used under Part 121) except those manufactured after October 11, 1991.
(6) Requirements pertaining to the use of boom microphones have been clarified.
(7) The resolution readout column in each of the appendices has been made applicable only to aircraft manufactured after October 11, 1991.
The changes above were coordinated with the NTSB staff who have indicated agreement that this final rule meets the intent of the NTSB recommendations in its letter of June 19, 1987.
In addition the above changes, Parts 23 and 27 have been revised to include airworthiness requirements for flight and voice recorders. In the proposal such airworthiness requirements were only in Parts 25 and 29, and all operators subject to flight and voice recorder requirements were referred to those parts. In the interest of consistency, the final rule includes airworthiness requirements for flight and voice recorders in Parts 23, 25, 27, and 29. References in the operating rule have been revised accordingly.”
23.1459 Flight recorders
There is no corresponding rule in CAR 3 or the Airship Design Criteria.
Amendment 23-35 and Subsequent
Significant changes between the proposed rule and the final rule are summarized below. These changes were discussed in the appropriate sections of the comment discussion above:
“(1) The compliance dates have been extended from 2 years to 3 years.
(2) Pre-wiring requirements in Sec. 91.35 and Sec. 135.52 have been deleted.
(3) The requirements for airplanes currently equipped with a digital date bus are clarified in Secs. 121.343(e) and 125.225(c).
(4) Certain of the parameters in Appendix B of Part 121 have been made optional.
(5) Aircraft required to be upgraded under Sec. 135.152(b) must meet the 11- parameter or 17-parameter flight recorder requirements (currently required of certain airplanes used under Part 121) except those manufactured after October 11, 1991.
(6) Requirements pertaining to the use of boom microphones have been clarified.
(7) The resolution readout column in each of the appendices has been made applicable only to aircraft manufactured after October 11, 1991.
The changes above were coordinated with the NTSB staff that has indicated agreement that this final rule meets the intent of the NTSB recommendations in its letter of June 19, 1987.
In addition the above changes, Parts 23 and 27 have been revised to include airworthiness requirements for flight and voice recorders. In the proposal such airworthiness requirements were only in Parts 25 and 29, and all operators subject to flight and voice recorder requirements were referred to those parts. In the interest of consistency, the final rule includes airworthiness requirements for flight and voice recorders in Parts 23, 25, 27, and 29. References in the operating rule have been revised accordingly.”
23.1461 Equipment containing high energy rotors
There is no corresponding rule in CAR 3.
The corresponding rule in the Airship Design Criteria, FAA-P-8110-2, Change 2, is section 6.41.
Amendment 23-20 and Subsequent
A proposed revision to NPRM 75-23 explains this rule as follows: “By adding a new Sec. 23.1461, following Sec. 23.1449, that would be substantively identical to the proposed new Sec. 25.1461. By adding a new Sec. 25.1461: This proposal would add requirements for protection against the failure of equipment containing high energy rotors, such as turbine engine starters, air cycle machines, and certain cooling fans. Experience has shown that failures which release the energy stored in these rotors may result in engine or structural damage, fires, or injury to occupants.
The language in this proposal is identical to Secs. 27.1461 and 29.1461.”
This regulation requires that equipment containing high-energy rotors meet § 23.1461(b), (c) or (d). An acceptable means of compliance to § 23.1461 is given in AC 20-128A, “Design Considerations for Minimizing Hazards Caused by Uncontained Turbine Engine and Auxiliary Power Unit Rotor Failure.”
Amendment 23-49 and Subsequent
A proposed revision to NPRM 94-21 clarifies this rule as follows: “This proposal would revise paragraph (a) of this section to clarify that the requirements apply to high energy rotors included in an auxiliary power unit (APU). Following the addition of this section to part 23, the FAA issued a policy message that showed Sec.
23.1461 was adopted to cover equipment such as APUs and constant speed drives that may be installed on small airplanes. The proposed revision of paragraph (a) will clarify the applicability of this section as identified in that policy material.”
Amendment 23-49 is additionally clarified by Final Rule, Docket 27806, as follows:
“This proposal would revise paragraph (a) of this section to clarify that the requirements apply to high energy rotors included in an auxiliary power unit (APU).
One comment was received on this proposal. The JAA and the CAA noted that the JAA does not agree that the requirements of this section are applicable to APUs.
They suggest that the proposed changes to paragraph (a) not be adopted.
In the preamble of the notice, the FAA identified policy issued after this section was adopted. That policy indicated that the section was applicable to "equipment such as APUs and constant speed drives," but this policy was not widely distributed to all FAA offices. The proposal in the notice does not alter the policy applicability, but it does clarify the policy.
Removing the proposed change would not alter the situation. The FAA defines "Equipment containing high energy rotors" to include APUs and constant speed drives. In cases where rotor containment has been demonstrated by complying with JAA-APU or FAA TSO C77a, this compliance will be examined by the FAA office responsible for the airplane certification. If it is found that this demonstration also meets the requirements of Sec. 23.1461, it will be accepted for the airplanes compliance.”