Circling Approach

James Albright (a former G450 driver)

Updated: 2013-10-26

Circling at minimums can get you killed so know the minimums, raise those minimums when you can, and take advantage of the PlaneView cockpit.

Everything here is from the references shown below, with a few comments in an alternate color.

 Approach Category

The G450 is either a Category C aircraft or a Category D aircraft, depending on the installation of ASC 007C. You cannot change your category from D to C without maintenance logbook action. You can, however, change from C to D as a pilot. See G450 Approach Category.

I recommend you never circle this airplane using Category C minimums because a stable approach is impossible given Category C speeds and turn radii.

G450 Operating Manual Procedure

[G450 Airplane Operating Manual §06-05-30]

1. Pattern entry: airspeed 200 knots, review approach and missed approach procedure, review VREF and go-around power, set radios and nav display, set marker receiver on, check crossing altitude fix.

   The circling maneuver may be initiated from either a precision or non-precision instrument approach procedure and must be conducted entirely by external visual references. A normal instrument approach is flown until visual contact with the runway environment or to the Minimum Descent Altitude (MDA). As the circling maneuver is not an instrument maneuver, sufficient visual references to maneuver the aircraft to a landing must be maintained at all times.

   Maneuvering may begin once within 2.3 nm (Category D) or 1.7 nm (Category C).

2. Outbound turn: complete in-range checklist or appropriate checklist, PF calls for Flaps 10°, airspeed 180 knots.

3. Inbound turn: PF calls for landing gear down & flaps 39°, airspeed set to VREF+5 knots, complete Before Landing Checklist. If single engine: PF calls for Flaps 20°, airspeed set to VREF+10 knots, PF call for landing gear down not later than descent from MDA.

4. At the Fix: Establish 1000-1200 FPM rate of descent using vertical speed, VNAV or available ILS glide path, reduce descent approaching MDA & level off not lower than MDA.

5. Pattern Entry: Maintain VREF+5 knots during circling, with runway in sight, maneuver to enter pattern on downwind or base leg.

6. Turning Base Leg: ensure landing gear is down.

7. Threshold: maintain VREF.

   If visual contact with the airport (or the landing runway, when below MDA) is lost during the circling maneuver, a missed approach must be initiated. The initial turn should be made, or continued, toward the runway until established on the published missed approach course, or as directed by approach control.

   The initial turn is not always made toward the runway at all airports.

 Stacking the Deck in Your Favor

PlaneView gives you a few visual cues on the map display that can help with runway offsets.

Map Display

By sizing the inner ring to 2 nm, you have a good idea where 2.3 nm from the airport boundary is:

ILS Feathers

If a perpendicular runway has an ILS, for example, varying the size of the inner display ring can be useful. The length of the ILS feather is equal to the inner ring for 1, 2, 3, 4, and 5 nm; it remains 5 nm up to a ring of 50 nm, after which time it is no longer in view.

Jeppesen Charts

Before you protest about the propriety of using an approach chart for navigation, allow me to offer two words: situational awareness.

 Three Possibilities

Circling can get you killed and the dirty little secret is that everyone knows this. So what you end up with, in the "circling approach" classification, are three possibilities:

1. Simulator Practice. Circling in the simulator is nothing like real life. Take the classic KMEM approach to Runway 27 circle to Runway 18R. Memphis is filled with ILS's and having to circle at night there on a moonless night leaves you with almost no visual cues. But you need to do it every six months just to satisfy the requirements of your instrument rating. The way we train to circle gives us unrealistic confidence and expectations about how it will be in real life.

2. Airport Maneuvering. Teterboro, for example, has to share airspace with La Guardia and Newark, so you end up with things like an ILS to Runway 6, circle to Runway 1. This is not a real circling approach, they ask you to begin your maneuvering outside DANDY intersection, which is 6.0 nm from the end of the runway. Don’t even think about taking it in to the radii required by the approach category or the visibility minimums. If this airport is at circling minimums and they won’t give you a straight in approach, find someplace else to land.

3. Real Circling. If you are in the weather, at minimums, having to circle within the published circling approach area, you are at risk. Depending on the rules used to set up that area, you may have no margin for error. Do you want to cut it that close? At normal approach speeds in the G450 you can improve your odds by only circling under Category D minimums. Chicago Midway, for example, can be safely circled at 2.3 nm, but a Stabilized Approach is impossible at 1.7 nm because of your turn radius and the need to be on the extended runway centerline and on glide path no later than 500 feet AGL.

 References:

Gulfstream G450 Aircraft Operating Manual, Revision 35, April 30, 2013.

Gulfstream G450 Aircraft Service Change 007C, Maximum Landing Gross Weight, 58,500 pounds, Category C, Provisions, October 26, 2011

Gulfstream G450 Airplane Flight Manual, Revision 35, April 18, 2013

United States Standard for Terminal Instrument Procedures (TERPS), Federal Aviation Administration 8260.3B CHG 19, 5/15/02