(a) General. Unless otherwise authorized by ATC, each pilot who
has two-way radio communications failure when operating under IFR shall
comply with the rules of this section.
(b) VFR conditions. If the failure occurs in VFR conditions, or
if VFR conditions are encountered after the failure, each pilot shall
continue the flight under VFR and land as soon as practicable.
(c) IFR conditions. If the failure occurs in IFR conditions, or
if paragraph (b) of this section cannot be complied with, each pilot shall
continue the flight according to the following:
(1) Route. (i) By the route assigned in the last ATC clearance
received;
(ii) If being radar vectored, by the direct route from the point of
radio failure to the fix, route, or airway specified in the vector
clearance;
(iii) In the absence of an assigned route, by the route that ATC has
advised may be expected in a further clearance; or
(iv) In the absence of an assigned route or a route that ATC has
advised may be expected in a further clearance, by the route filed in the
flight plan.
(2) Altitude. At the highest of the following altitudes or
flight levels for the route segment being flown:
(i) The altitude or flight level assigned in the last ATC clearance
received;
(ii) The minimum altitude (converted, if appropriate, to minimum flight
level as prescribed in §91.121(c)) for IFR operations; or
(iii) The altitude or flight level ATC has advised may be expected in a
further clearance.
(3) Leave clearance limit. (i) When the clearance limit is a fix
from which an approach begins, commence descent or descent and approach as
close as possible to the expect-further-clearance time if one has been
received, or if one has not been received, as close as possible to the
estimated time of arrival as calculated from the filed or amended (with
ATC) estimated time en route.
(ii) If the clearance limit is not a fix from which an approach begins,
leave the clearance limit at the expect-further-clearance time if one has
been received, or if none has been received, upon arrival over the
clearance limit, and proceed to a fix from which an approach begins and
commence descent or descent and approach as close as possible to the
estimated time of arrival as calculated from the filed or amended (with
ATC) estimated time en route.