Do manual da FAA sobre voos IFR (página 4-17) . Parece que é o equipamento mínimo necessário para voar a abordagem.
In some cases, other types of navigation systems, including radar, are
required to execute other portions of the approach or to navigate to
the IAF (for example, an NDB procedure turn to an ILS, or an NDB in
the missed approach, or radar required to join the procedure or
identify a fix). When ATC radar or other equipment is required for
procedure entry from the en route environment, a note is charted in
the plan view of the approach procedure chart (for example, RADAR
REQUIRED or AUTOMATIC DIRECTION FINDER (ADF) REQUIRED). When radar or
other equipment is required on portions of the procedure outside the
final approach segment, including the missed approach, a note is
charted in the notes box of the pilot briefing portion of the approach
chart (for example, RADAR REQUIRED or DISTANCE MEASURING EQUIPMENT
(DME) REQUIRED). Notes are not charted when VOR is required outside
the final approach segment. Pilots should ensure that the aircraft is
equipped with the required NAVAIDs to execute the approach, including
the missed approach. Refer to the AIM paragraph 5-4-5 for additional
options with regards to equipment requirements for IAPs.
Mais tarde, eles falam sobre as abordagens de radar (página 4-71)
The two types of radar approaches available to pilots when operating
in the NAS are precision approach radar (PAR) and airport surveillance
radar (ASR). Radar approaches may be given to any aircraft at the
pilot’s request. ATC may also offer radar approach options to aircraft
in distress regardless of the weather conditions or as necessary to
expedite traffic. Despite the control exercised by ATC in a radar
approach environment, it remains the pilot’s responsibility to ensure
the approach and landing minimums listed for the approach are
appropriate for the existing weather conditions considering personal
approach criteria certification and company OpSpecs.
Eles também podem ser úteis para ajudar aeronaves com deficiência em (página 4-74).
Perhaps the greatest benefit of either type of radar approach is the
ability to use radar to execute a no gyro approach. Assuming standard
rate turns, ATC can indicate when to begin and end turns. If
available, pilots should make use of this approach when the heading
indicator has failed and partial panel instrument flying is required.