23.1391 Minimum intensities in the horizontal plane of position lights
The corresponding rule in CAR 3 is CAR 3.702.
The corresponding airworthiness criteria is section 6.28, Airship Design Criteria, FAA-P-8110-2, Change 2.
See § 23.1383 for guidance on non-required light installations.
Amendment 23-43 and Subsequent
A proposed revision in NPRM 90-23 explains this amendment as follows: “Section
23.1391 is amended in the section heading by removing the words "forward and rear" and in the table by removing the words "(forward red and green)" and inserting in their place "(red and green)".”
These changes are necessary for compatibility with revised § 23.1385.
23.1393 Minimum intensities in any vertical plane of position lights
The corresponding rule in CAR 3 is CAR 3.702.
The corresponding airworthiness criteria is section 6.29, Airship Design Criteria, FAA-P-8110-2, Change 2.
See § 23.1383 for guidance on non-required light installations.
Amendment 23-43 and Subsequent
This amendment removed the words “forward and rear” in the section heading.
These changes are necessary for compatibility with revised § 23.1385.
23.1395 Maximum intensities in overlapping beams of position lights
The corresponding rule in CAR 3 is CAR 3.702.
The corresponding airworthiness criteria is section 6.30, Airship Design Criteria, FAA-P-8110-2, Change 2.
See § 23.1383 for guidance on non-required light installations.
Amendment 23-43 and Subsequent
A proposed revision in NPRM 90-23 explains this amendment as follows: “Section
23.1395 is amended in the section heading by removing the words "forward and rear".”
This change is necessary for compatibility with revised § 23.1385.
23.1397 Color Specifications
The corresponding rule in CAR 3 is CAR 3.703.
The corresponding airworthiness criteria is section 6.31, Airship Design Criteria, FAA-P-8110-2, Change 2.
See § 23.1383 for guidance on non-required light installations.
Original Issue and Subsequent
See AC 20-74, “Aircraft Position and Anticollision Light Measurements,” for guidance on color measurements.
Amendment 23-11 and Subsequent
A proposed revision in NPRM 70-21 changed the color requirements for Aviation White as follows: “It is proposed to expand the chromaticity-coordinate range for the color Aviation White in order to provide for the use of white condenser-discharge anticollision lights, including Xenon types, in the implementation of proposal 1.”
23.1399 Riding light
No policy available as of December 31, 2007.
This rule was adopted on February 1, 1965 as a recodification of CAR 3.704.
There is no corresponding airworthiness criteria in the Airship Design Criteria.
23.1401 Anticollision light system
The corresponding rule in CAR 3 is CAR 3.705.
The corresponding airworthiness criteria is section 6.32, Airship Design Criteria, FAA-P-8110-2, Change 2.
See § 23.1383 for guidance on non-required light installations.
Original Issue and Subsequent
If certification for night operation is sought, an anticollision light system, according to this section, is required.
See AC 20-74, “Aircraft Position and Anticollision Light Measurements,” for guidance on anticollision light measurements.
The flash rate of supplemental lights does not have to be applied to the anticollision light flash rate, but these lights should be checked to verify there is no unsafe condition associated with their use.
Amendment 23-11 and Subsequent A proposed revision in NPRM 70-21 explains this amendment as follows: “(1) It is proposed to amend Sec. 23.1401 (and the corresponding sections of Parts 25, 27, and
29) to permit the use of either aviation red or Aviation White anticollision lights. The regulations now require that each anticollision light must be aviation red. However, neither the research conducted in the past by the FAA, and by others, nor the arguments submitted in response to Notice 70-7 by proponents of each color have conclusively established that one color is superior to the other at comparable intensities. Current FAA/NASA research may shed new light on this question.
It is clear, however, that if the red color for anticollision lights were changed to white, the anticollision light intensity could be increased by a factor of 3 to 5 (without increasing the electric power consumption) by merely removing the red filter needed to meet current standards, or by replacing it with a white light (condenser discharge or other type) that uses about the same amount of power. Alternatively, if the regulation permitted Aviation White anticollision lights, the currently prescribed intensities could be produced with one-fifth to one-third of the electric power now being used by the red anticollision lights. Although it is true that the use of Aviation White could introduce a backscatter problem on some aircraft, we believe that this problem can be solved by the relocation of lights, by appropriate masking, or by other methods, as has already been done with respect to the white "supplementary" high-intensity lights installed on many aircraft now in service. Some of the comments suggested that safety might be compromised by permitting aircraft using differently colored anticollision lights to operate in the same airspace. The FAA does not agree.
311 Many aircraft currently operating in the United States do not now display red anticollision lights exclusively, since the current regulations permit the display of high-intensity flashing white lights (and even red and green lights) as "supplementary" lights. Frequently, the "supplementary" white lights are seen first as the aircraft is approached. The use of such "supplementary" lights has been permitted for more than 10 years and there has been no adverse effect on safety.
Therefore, there is no reason to believe that the optional use of either red or white anticollision lights in the future would compromise safety in any way.
On the other hand, since the standards of the International Civil Aviation Organization (ICAO) now specify red as the color for anticollision lights, the adoption of this proposal would make it necessary to file a formal notice of difference with ICAO.
(2) It is proposed to expand the chromaticity-coordinate range for the color Aviation White in order to provide for the use of white condenser-discharge anticollision lights, including Xenon types, in the implementation of proposal 1.
(3) It is proposed to increase the minimum effective intensities for anticollision lights and to make that increase applicable to both red and white lights on aircraft TC in the future. A majority of the persons responding to Notice 70-7 indicated that the currently prescribed intensity level for anticollision lights should be raised.
In view of the fact that this increase would apply only to anticollision lights installed on aircraft for which an application for TC is made after the effective date of any final amendment containing this proposal, and in view of the current state-of-the-art in anticollision lights, the FAA considers that the application of the proposal of all aircraft is feasible.
On the question of what increase in anticollision light intensity should be made, those who responded to Notice 70-7 offered suggestions that varied widely; but most recommended a four-fold increase over current levels. This corresponds roughly to the increase in intensity that would be attained by removing the red filter from existing anticollision lights, and is within the performance capability of state-of-theart condenser-discharge lights. The FAA believes this intensity recommendations has merit, and it is proposed to increase currently prescribed anticollision light intensities by a factor of four.
Contrary to the suggestion contained in various comments on Notice 70-7, the FAA believes that an intensity level standard that includes a specified infrared signal content for use with Pilot Warning Indicators (PWI) would be premature. The FAA considers that mandatory action on infrared signal content should await completion of current evaluations of the PWI system concept on civil aircraft. However, the proposed standard would not prevent any manufacturer from providing an infrared signal in his anticollision lights.
312 There were also suggestions that the current anticollision light intensity should be retained for ground operation. However, the FAA does not consider that this is necessary since, under current rules, the anticollision lights may be dimmed or even turned off during ground operations.”
This amendment is clarified by Final Rule, Docket 10129, as follows: “One commentator indicated that the FAA may have underestimated the problems associated with removal of the red filter on the anticollision light on existing aircraft.
The commentator pointed out that it may be impossible to meet the current field-ofcoverage requirements because of the need to mask the unfiltered light to eliminate back-scatter. While the FAA recognizes this problem, it should be noted that it was not proposed to require anyone to remove the red filters on existing aircraft.
Moreover, if an operator elected to do so, he would not be required to meet the new intensity requirements. Furthermore, he could relocate the light to minimize the back-scatter problem. Another comment expressed an objection to the proposed increase in the intensity level of anticollision light systems for future aircraft on the grounds that for small aircraft using red anticollision lights, power requirements would be unreasonable, service life short and reliability low, and that for small aircraft using the white anticollision lights, it would be possible to shield them for purposes of back-scatter without a reduction in the required field-of-coverage. The FAA is aware that for red anticollision lights more electrical power would be needed to meet the new requirements than has been provided in the past. However, the FAA believes that this additional power capacity can be provided on future aircraft at reasonable cost, without incurring a low-service-life or low-reliability penalty.
Moreover, a manufacturer would now have the option of installing a white anticollision light, thereby eliminating the power problem. The back-scatter problems referred to by the commentator can be solved without diminishing the fieldof-coverage by installing a system consisting of three lights, one at each wing-tip and one on the tail.”
There is no restriction on mixing aviation red and Aviation White anticollision lights on the same airplane. Also, there is no restriction on the ratio of red to white provided the light displayed in any one direction is either aviation red or Aviation White.
Some white supplementary lights have been presented for certification as anticollision lights. The visible limit of such lights may converge at some point forward and aft of the airplane so from this point to the airplane neither light is visible. The maximum allowable distance to such convergence is 1,200 feet.
The regulations (§ 23.1397) require that Aviation White’s “X” coordinate be no less than 0.300 and no greater than 0.540 (ICAO) Annex 8 requirement). Xenon flash tubes can exceed the “X” limit for some energy levels (20 to 40 joule range). For the function of an anticollision light, an occasional excursion beyond the 0.300 limit would not adversely affect safety or the performance of the intended function. FAA has been advised by the National Bureau of Standards (NBS) the measurement
313 accuracy of the “X” value of chromaticity coordinates includes an error tolerance of plus or minus 0.008. It was not envisaged that filtering would be required on Xenon flash tubes to meet the Aviation White limits since the color can be effectively limited by capacitor circuitry to control the energy level of individual flashes. The maximum joules per flash should be such: 1) the 0.300 will not be exceeded more than 68 percent of the time and 2) 0.292 will not be exceeded 99.7 percent of the time (3 sigma), which includes the measurement error tolerance suggested by NBS.
Amendment 23-20 and Subsequent
A proposed revision in NPRM 75-23 explains this amendment as follows: “The present anticollision light rule in Sec. 23.1401(b) requires that the field of coverage extend in each direction within at least 30° above and 30° below the horizontal plane of the airplane. The FAA believes that this minimum coverage should be increased.
Under the present rule, visibility of the light may be less than is needed when the airplane is approached by another aircraft ascending or descending, or when the airplane is banked at more than 30°. This proposal would expand the present field of coverage so that it extends in each direction within at least 75° above and 75° below the horizontal plane of the airplane. In addition, this proposal would specify at least a 20-candle effective intensity in the 30° to 75° field of coverage, thereby increasing the probability of seeing the airplane from other aircraft (including air rescue aircraft) and from control towers.”
Amendment 23-49 and Subsequent
A proposed revision in NPRM 94-21 revises § 23.1401 to require installing an anticollision light system on all part 23 airplanes. Current § 23.1401 requires an anticollision light system only if certification for night operations is requested.
314 Section 5. Safety Equipment
23.1411 General
The corresponding rules in CAR 3 are CAR 3.711, 3.713, 3.714 and 3.715.
The corresponding airworthiness criteria are sections 6.33, 6.34 and 6.35, Airship Design Criteria, FAA-P-8110-2, Change 2.
Amendment 23-17 and Subsequent
A proposed revision in NPRM 75-10 explains this amendment as follows: “By amending Sec. 23.1411 in a manner substantively identical to that proposed for Sec.
27.1411. The proposal would add a requirement for stowage provisions for all safety equipment in Sec. 27.1411 and would provide standards applicable to such stowage provisions.”
Amendment 23-36 and Subsequent
There is no proposed change to § 23.1411 by the NPRM, but Final Rule, Docket 25147, explains this amendment as follows: “One commenter suggests that the regulatory references in the notice should be crosschecked with the latest revisions of Part 23. As a result of reviewing the FAR, the FAA identified several sections of Part 23, which need to be changed for compatibility with the new requirements for dynamic testing of seat/restraint systems. The regulatory changes identified by this review are not substantive but provide consistency with the other changes made by this amendment. This review resulted in several additions to this final rule.
Section 23.1411 is revised so that paragraph (b)(2) refers to section 23.561(b)(3).”
23.1413 Safety Belts and Harnesses [Removed]
See guidance for section 23.785 in this AC.
23.1415 Ditching equipment
No policy available as of December 31, 2007.
This rule was adopted on February 1, 1965 as a recodification of CAR 3.716, 3.717 and 3.718.
The corresponding airworthiness criteria is section 6.36, Airship Design Criteria, FAA-P-8110-2, Change 2.