(1) For the operating capacity: the discharge rate, temperature, end-point voltage, etc.; and
(2) For the airworthiness requirement: the inspection schedule, useful battery life, end-of-life, etc.
JAA ACJ 23.1353(h) is acceptable for FAA certification.
23.1357 Circuit protective devices Original Issue and Subsequent This rule allows only one essential circuit on one circuit protective device. The intent of the rule is met for installations that integrate position and anticollision lights on one wire when no single failure can cause the loss of any of the following:
(a) More than all anticollision lights.
(b) More than all position lights.
(c) More than one position light and the anticollision light adjacent to it.
The requirement in § 23.1357(e) applies to fuses for all circuits, not just essential circuits.
Although spare fuses for non-essential systems and equipment do not have to be resettable in flight.
The phrase “essential to safe operation,” as used in part 135, Appendix A, paragraph 64, and the phrase “essential to flight safety” in § 23.1357(b) have the same meaning as “essential to safety in flight” in § 23.1357(d) and “essential to flight safety” in § 23.1357(b).
All of these phrases are descriptive of equipment installed in order to comply with the airworthiness or operational requirements. The FAA recognizes that some required circuit protection devices are associated with circuits that can have no significant impact on safety in flight. Therefore, the responsible Aircraft Certification Office (ACO), in conjunction with the applicant, should identify which circuits and circuit protection devices are essential to safety in flight. The identified circuits should comply with § 23.1357(d) regarding the pilot’s ability to reset them in flight.
Fuel quantity indicators are required by regulation but are not essential to safety in flight. The loss of an indicator will increase the pilot’s workload, but it will not, in itself, cause either a loss or a forced landing of the airplane. It is acceptable, therefore, to have a protected circuit that includes more than one required indicator, which includes a fuel quantity indicator.
Good design practice would include placing multiple indicators of the same parameter on separate protected circuits, and we encourage the use of warnings for low fuel, high oil temperature, etc., to mitigate the effects of loss of indication.
The intent of § 23.1357(b) is that, in the case of an essential load, its individual circuit should be the only load on an individual circuit protection device. This intent was explicitly stated in Amendment 23-20.
195 For part 23 applications, the definitions of a switch and a circuit breaker are as follows: a switch is a device for opening and closing or for changing the connection of a circuit; a circuit breaker is a device designed to open and close a circuit by non-automatic means and to open the circuit automatically at a predetermined overload of current, without injury to itself when properly applied within its rating. Consequently, circuit breakers used for operational functions are not acceptable in that they are not performing their intended function, which is protection against overloads. Circuit breakers, even those suitable for frequent operation, should not be used as a switch to perform procedural functions.
A combination switch/circuit breaker is a device which can perform both as a switch for opening and closing a circuit as well as a circuit breaker, automatically opening the circuit at a predetermined overload current.
23.1359 Electrical system fire protection See guidance in Section 23.853 of this AC.
23.1361 Master switch arrangement No policy available as of June 30, 2001.
23.1365 Electric cables and equipment Original Issue and Subsequent Section 23.1365 requires that each cable that would overheat in a circuit overload or malfunction be at least flame resistant and not emit dangerous quantities of toxic fumes. The compliance methods for the flame resistance requirement are in AC 23-2, Flammability Tests. To aid in meeting the toxic fume requirement, the FAA has removed MIL-W-5086 wire from the listing of approved wires in AC 43.13-1B, Acceptable Methods, Techniques, and PracticesAircraft Inspection and Repair.
See guidance in Section 23.853 of this AC for flammability.
Amendment 23-14 and Subsequent The flame resistance and toxic fume requirements are applicable to equipment associated with the cable as well as the cable itself.
23.1367 Switches Original Issue and Subsequent Switches are required to be labeled as to operation and the circuit controlled. A switch that operates by a push once for ON and once for OFF should be labeled “PUSH OFF/ON.”
Switches are also required to be accessible to the flight crew. The intent of this rule is that those switches that are installed in the cockpit should be accessible to a flight crew member if manual operation is necessary for safety of flight.
200 LIGHTS
23.1381 Instrument lights No policy available as of June 30, 2001.
23.1383 Taxi and landing lights No policy available as of June 30, 2001.
23.1385 Position light system installation Original Issue and Subsequent Guidance on light measurements can be found in AC 20-74, Aircraft Position and Anticollision Light Measurements. Additional guidance on position lights can be found in AC 20-30B, Aircraft Position Light and Anticollision Light Installation.
Guidance on flame resistance can be found in AC 23-2, Flammability Tests.
The intent of the rule in § 23.1357 is met for installations that integrate position and anticollision lights on one wire when no single failure can cause the loss of any of the following:
(a) More than all anticollision lights.
(b) More than all position lights.
(c) More than one position light and the anticollision light adjacent to it.
Position lights are not required for airplanes limited to Day VFR operation (placarded for VFR Day). If approved for Night VFR or IFR, then position lights are required per §§ 23.1385 through 23.1395. They should be listed on the kinds of operation equipment list (§ 23.1559(b)) and included in the Limitations Section of the Airplane Flight Manual (§ 23.1583(h)).
23.1387 Position light system dihedral angles No policy available as of June 30, 2001.
23.1389 Position light distribution and intensities No policy available as of June 30, 2001.