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5 Answers

Communication Failure

Asked by: 8727 views Airspace, FAA Regulations


Scenario: Assume a aircraft VFR (not on a IFR flight plan in VFR conditions) and radio failure occurs after entering Class C or Class B.

I do not see any guidance in the AIM pertaining to radio failure procedures while VFR within Class B or Class C airspace. The AIM does cover Class D VFR radio failure procedures.

AIM 4-2-13 only mentions Class D  procedures. It does not mention  Class C or Class B. Also AIM 6-4-1 discusses IFR procedures but does mention VFR. However, there is mention of VFR in AIM 6-4-1.  But is this VFR reference in AIM 6-4-1 for IFR operations in VFR conditions or for VFR operations (not on a IFR flight) ? I understand the IFR procedures but  what are the procedures when flying VFR (not on a IFR flight plan) in Class C and Class B?


Thank you,



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5 Answers

  1. Jay on Mar 22, 2013

    AIM paragraphs 6-4-1 B states that: “Whether two-way communications failure constitutes an emergency depends on the circumstances, and in any event, it is a determination made by the pilot.”

    I wouldn’t consider this an emergency.. So therefore couldn’t use 91.3(b) (The PIC may deviate from any rule of this part to the extent required to meet that emergency) in order to land at the class B or C airport.

    With that being said, I couldn’t comply with class B & C entry requirements:

    91.130 Class C – Arrival or through flight – you must establish two way prior to entering.
    91.131 Class B – You must get an ATC clearance before operating an aircraft in that area.

    Since our radios are inop, we don’t meet those entry requirements. Since we concluded were not in an emergency, we can’t enter that airspace.

    I would then revert back to 91.185(b) – (If the failure occurs in VFR, continue and land as soon as practicable.) Also the note in AIM 6-4-1 which says land as soon as PRACTICABLE does not mean as soon as POSSIBLE…..

    Finally, I wouldn’t enter class B or C and I would land as soon practicable – nearest.

    BUT……… You are the PIC.. so if you believe it is an emergency (AIM 6-4-1 B), then you can use 91.3(b) which allows you to break any rules to meet the needs of the emergency.

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  2. Jay on Mar 22, 2013

    In 91.131 and 91.130 in the general sections (a), it says the aircraft operation must be conducted in compliance with 91.129 – which is operations in a class D airspace…

    So then my interpretation of that is they want you to treat a radio failure in class B or C like you would in class D..

    If in VFR, Wx conditions are at or above minimums, maintain visual contact with the tower & wait for steady green.

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  3. John D. Collins on Mar 22, 2013

    I think Jay has offered a reasoned interpretation. I would only add that in Class C and B, you are required to have a transponder with altitude reporting. If you haven’t lost your electrical system and the transponder appears to be working, you should also consider squawking 7600.

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  4. Mark Kolber on Mar 22, 2013

    I’m not aware of any specific regulatory guidance or official interpretation on the subjet, so this is a personal take:

    The regs on communication requirements in certain airspace require not only the establishment but the =maintenance= of communications. See FAR 91.126(d) (Class G towers), 91.127(c) (Class E Towers), 91.129(c)(1) (Class D), 91.130(c)(1) (Class C), 91.131(c)(2) (Class B).

    Lost communications, VFR? You’re no longer “supposed” to be in that airspace since you’re no longer capable of maintaining communications. But, as we know from the light gun procedures, there is some leeway here, particularly where the loss is fue to radio failure.

    In discussing communication failure, the AIM starts with:

    6-4-1. Two-way Radio Communications Failure
    a. It is virtually impossible to provide regulations and procedures applicable to all possible situations associated with two-way radio communications failure. During two-way radio communications failure, when confronted by a situation not covered in the regulation, pilots are expected to exercise good judgment in whatever action they elect to take. Should the situation so dictate they should not be reluctant to use the emergency action contained in 14 CFR Section 91.3(b).

    It’s tempting to try to apply the light gun procedures for Class D but I think automatically following it is a mistake when we are talking about mixing with airline traffic in even a quiet Class C or flying in busy Class B airspace.

    With that as a backdrop, my default “good judgment” response is to exit the airspace by the shortest and best route(which may be up or down as well as lateral).

    But I recognize the “exercise good judgment” may suggest a different answer based on the circumstances. For example, if I were landing at the primary, given a final vector to intercept final, and just about ready to be switched to Tower for the landing clearance, I’d be more likely to continue to do what is most likely expected of me – continue for landing. Unless an exit from the airspace was close and less than 90° away, I’d be far more concerned with the impact on traffic (not to mention the impact on ME!) by turning around trying to avoid both departing and arriving aircraft.

    So, my answer, FWIW, is, exit the airspace by the most appropriate means unless the circumstances make it impractical.

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  5. Dan Chitty on Mar 22, 2013

    Thank you to all for the feedback. All comments are very appreciated.



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