Radar Approaches, Where Are Porfile Views Published ?

[rhscholz]

Today, I flew a practice no-gyro ASR approach to RWY 23 at Terre Haute International, Indiana (KHUF). The controller failed to tell me the altitude at the point from which to commence descent to the MDA, so I ended up with a steeper than normal descent gradient.

1. Why are radar approaches not charted (profile views) and included in the U.S. Terminal Procedures Publications ?
I am assuming they are designed to have a 3 deg descent gradient, but it sure would be nice to know where the point from wich to commence descent is located and what the altitude is supposed to be at that point.

2. Where can one find the profile views of radar approaches ?

I certainly appreciate if anybody can point me to that FAA information source

 

[John Collins]

The controller is supposed to assign you your altitude and advise you when to descend. The following is from the AIM, section 5-4-11 Radar Approaches:​

a. The only airborne radio equipment required for radar approaches is a functioning radio transmitter and receiver. The radar controller vectors the aircraft

to align it with the runway centerline. The controller continues the vectors to keep the aircraft on course until the pilot can complete the approach and landing by visual reference to the surface. There are two types of radar approaches: Precision (PAR) and Surveillance (ASR).​

​

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b. A radar approach may be given to any aircraft upon request and may be offered to pilots of aircraft in distress or to expedite traffic, however, an ASR might not be approved unless there is an ATC operational requirement, or in an unusual or
emergency situation. Acceptance of a PAR or ASR by a pilot does not waive the prescribed weather minimums for the airport or for the particular aircraft operator concerned. The decision to make a radar approach when the reported weather is below the established minimums rests with the pilot.​

​

​

c. PAR and ASR minimums are published on separate pages in the FAA Terminal Procedures Publication (TPP).​

1. A PRECISION APPROACH (PAR) ...
2. A SURVEILLANCE APPROACH (ASR) is one in which a controller provides navigational guidance in azimuth only. The pilot is furnished headings to fly to align the aircraft with the extended centerline of the landing runway. Since the radar information used for a surveillance approach is considerably less precise than that used for a precision approach, the accuracy of the approach will not be as great and higher minimums will apply. Guidance in elevation is not possible but the pilot will be advised when to commence descent to the Minimum Descent Altitude (MDA) or, if appropriate, to an intermediate step-down fix Minimum Crossing

Altitude and subsequently to the prescribed MDA. In addition, the pilot will be advised of the location of the Missed Approach Point (MAP) prescribed for the procedure and the aircraft’s position each mile on final from the runway, airport or heliport or MAP, as appropriate. If requested by the pilot, recommended altitudes will be issued at each mile, based on the descent gradient established for the procedure, down to the last mile that is at or above the MDA. Normally, navigational guidance will be provided until the aircraft reaches the MAP. Controllers will terminate guidance and instruct the pilot to execute a missed approach unless at the MAP the pilot has the runway, airport or heliport in sight or, for a helicopter point-in-space approach, the prescribed visual reference with the surface is established.​

 

[kkoran]

Were you assigned an altitude before the approach?

ASR approaches, like VOR approaches, are generally not 3 degrees.

 

[HPNPilot1200]

1. Why are radar approaches not charted (profile views) and included in the U.S. Terminal Procedures Publications ?

I'm not sure why the procedures aren't charted by FAA/NACO. Jeppesen publishes charts for ASR and PAR procedures. As to the profile view, I'm honestly not sure. The AIM specifies that ATC will advise when to begin the descent.

 

[poadeleted20]

Bottom line on Q2 is "nowhere."

 

[rhscholz]

Re: Radar Approaches, Where Are Profile Views Published ?

The controller is supposed to assign you your altitude and advise you when to descend. The following is from the AIM, section 5-4-11 Radar Approaches:​

a. The only airborne radio equipment required for radar approaches is a functioning radio transmitter and receiver. The radar controller vectors the aircraft

to align it with the runway centerline. The controller continues the vectors to keep the aircraft on course until the pilot can complete the approach and landing by visual reference to the surface. There are two types of radar approaches: Precision (PAR) and Surveillance (ASR).​

b. A radar approach may be given to any aircraft upon request and may be offered to pilots of aircraft in distress or to expedite traffic, however, an ASR might not be approved unless there is an ATC operational requirement, or in an unusual or
emergency situation. Acceptance of a PAR or ASR by a pilot does not waive the prescribed weather minimums for the airport or for the particular aircraft operator concerned. The decision to make a radar approach when the reported weather is below the established minimums rests with the pilot.​

c. PAR and ASR minimums are published on separate pages in the FAA Terminal Procedures Publication (TPP).​

1. A PRECISION APPROACH (PAR) ...
2. A SURVEILLANCE APPROACH (ASR) is one in which a controller provides navigational guidance in azimuth only. The pilot is furnished headings to fly to align the aircraft with the extended centerline of the landing runway. Since the radar information used for a surveillance approach is considerably less precise than that used for a precision approach, the accuracy of the approach will not be as great and higher minimums will apply. Guidance in elevation is not possible but the pilot will be advised when to commence descent to the Minimum Descent Altitude (MDA) or, if appropriate, to an intermediate step-down fix Minimum Crossing

Altitude and subsequently to the prescribed MDA. In addition, the pilot will be advised of the location of the Missed Approach Point (MAP) prescribed for the procedure and the aircraft’s position each mile on final from the runway, airport or heliport or MAP, as appropriate. If requested by the pilot, recommended altitudes will be issued at each mile, based on the descent gradient established for the procedure, down to the last mile that is at or above the MDA. Normally, navigational guidance will be provided until the aircraft reaches the MAP. Controllers will terminate guidance and instruct the pilot to execute a missed approach unless at the MAP the pilot has the runway, airport or heliport in sight or, for a helicopter point-in-space approach, the prescribed visual reference with the surface is established.​

John,

thank you very much for your comments; I appreciate this. I knew about the AIM explanation of ASR approaches, hence I asked about recommended altitudes at each mile from the runway. However, these are predicated upon an initial altitude at the point from which descent begins.
If you don't know the location and altitude of this point, then the recommended altitudes during the descent are not much help to plan the descent.

 

[nosehair]

Re: Radar Approaches, Where Are Profile Views Published ?

I asked about recommended altitudes at each mile from the runway. However, these are predicated upon an initial altitude at the point from which descent begins.
If you don't know the location and altitude of this point, then the recommended altitudes during the descent are not much help to plan the descent.

It's not a 100% accurate, but wherever an ASR is to a runway that has a published ILS procedure, the initial altitude/descent point is the same as the ILS.