December 20, 2013

Mr. Richard Terrill

P.O. Box 2220

Saratoga, CA 95070-0220

Dear Mr. Terrill:

On April 2, 2013, (Docket No. FAA-2013-0344), you petitioned the Federal Aviation 

Administration (FAA) to clarify 14 CFR § 91.205(a)(11), which states, in pertinent part, for 

small civil airplanes certificated after March 11, 1996, in accordance with part 23 of this 

chapter, an approved aviation red or aviation white anticollision light system is required for 

VFR flight during the day. In the event of failure of any light of the anticollision light system, 

operation of the aircraft may continue to a location where repairs or replacement can be made. 

In your petition you requested clarification of 14 CFR § 91.205(a)(11) when you intended to 

refer to § 91.205(b)(11). In your petition, you request that the FAA reword § 91.205(b)(11) to 

clarify that this section only requires a single, fully operational anticollision light system. 

You state that when an aircraft has more than one set of anticollision lights installed on the 

aircraft (e.g. strobes and beacons), they are two separate systems such that if one set is not 

working the other could be used and the aircraft will still be airworthy. 

You suggest that the following language be added to the text of the regulation: “If an aircraft 

has two or more anticollision light systems installed, only one of the light systems must be 

fully operational for the aircraft to be airworthy. In aircraft with only one anticollision light 

system installed, in the event of a failure of any light of the anticollision light system, 

operation of the aircraft may continue to a location where repairs or replacement can be 

made.” You explain that amending this regulation will preclude misinterpretation that has led 

to unnecessary canceling of flights and will prevent frustration, thus benefitting the public 

interest. 

When the FAA responds to petitions for rulemaking, it must follow the requirements of 

14 CFR Part 11, particularly those guidelines outlined in 14 CFR § 11.73. As stated in that 

section, the FAA uses the following criteria when making a decision as to whether or not to 

amend current regulations based on a petition for rulemaking: 

1) the immediacy of the safety or security concerns the petition raises;

2) the priority of other FAA issues; and

3) the resources we have available to address these issues.
2

As discussed above, 14 CFR § 91.205(b)(11) requires an approved aviation red or aviation 

white anticollision light system for VFR flights during the day for small civil airplanes. As 

evident from the plain meaning of the regulation, this section only requires that an aircraft be 

equipped with a single anticollision system. See Final Rule preamble, 61 FR 5151 

(“[p]roposed new § 91.205(b)(11) would require that airplanes certified under § 23.1401 be 

equipped with an anticollision light system...”) [emphasis added]. Additionally, the 

airworthiness standard states that “[t]the airplane must have an anticollision system 

that...consists of one or more approved anticollision lights...” Therefore, when both strobe 

lights and beacons are approved and installed on an aircraft, they are considered to be the 

same anticollision lighting system. See § 91.209(b); Legal Interpretation to Daniel Murphy 

from Rebecca B. MacPherson, Assistant Chief Counsel for Regulations (January 11, 2011). 

The FAA does not agree the text of this regulation, as written, is ambiguous or requires 

clarification. The original intent of the regulation required that only one anticollision light 

system be required on each aircraft, and that the lights of that system be approved and 

governed by the airworthiness standards contained in § 23.1401. In general, there is no relief 

if any light of the anticollision light system has failed and in the event of failure of any light of 

the anticollision light system, an operation of an aircraft may continue to a location where 

repairs or replacement can be made. However, the FAA notes that relief may be granted 

under § 91.213(a), inoperative instruments and equipment. Following the master minimum 

equipment list approval process, it has allowed one or more anti-collision lights to be 

inoperative on certain makes and models, depending upon the configuration of the installed 

anti-collision light system. 

If you have any additional questions, you are encouraged to contact your local Flight 

Standards District Office (FSDO). Given the reasons outlined above, the FAA is unable to 

consider and thereby must deny your petition for rulemaking in accordance with 

14 CFR § 11.73.

Accordingly, Docket No. FAA-2013-0344 is being closed.

Sincerely,

/s/

John Barbagallo

Acting Deputy Director, Flight Standards Service