2
$\begingroup$

Based on regulation, there are several criteria for when an approach is stabilized. I want to ask:

  1. Only small changes in heading/pitch.

    How small?

  2. The aircraft is in correct landing configuration.

    What are those configurations?

  3. The aircraft speed is not more than Vref+20 or less Vref.

    Is this IAS or CAS or TAS?

$\endgroup$
  • $\begingroup$ As far as I know, stabilized approach criteria are defined by the airline, not in any regulation. $\endgroup$ – Bianfable Jun 24 at 9:56
  • $\begingroup$ Welcome to aviation.SE! For questions about regulations, please always tell us which country or regulator you're asking about. Regulations can be very different in different places. And when you quote a source, it's always good to tell us what that source is, and link to it if you can. $\endgroup$ – Pondlife Jun 24 at 16:08
2
$\begingroup$

Although I can’t find regulations regarding stabilized approaches in the FAR/AIM, the unofficial but generally accepted definition of a stabilized approach would be

  1. “Only small changes in heading/pitch.
    How small?”
    Small changes in heading and pitch would mean changes only necessary to maintain a ground track on the lateral guidance and a consistent airspeed on the glideslope. These are to compensate for drift due to things such as wind.

  2. “The aircraft is in correct landing configuration.
    What are those configurations?“
    Configuration is entirely dependent on the aircraft and situation. Typically it would include things like:
    Autopilot correctly set or off;
    Boost pump on;
    Carb heat to hot;
    Gas on the fullest tank, both, or on;
    Landing gear down and locked with indicator lights lit;
    Cowl flaps closed;
    Flaps at the correct setting;
    Mixture set at best power for density altitude;
    Prop speed set at fastest setting;
    Landing, position, and anti-collision lights (if not in clouds or fog) on;
    All auxiliary and/or unnecessary equipment off;
    Sterile cockpit;
    Seats and seatback set and locked in the upright position;
    Seatbelts and shoulder harnesses on and latched;
    Throttle/power set at a consistent setting to provide a descent rate on the glideslope;
    Landing checklists complete.

  3. “The aircraft speed is not more than Vref+20 or less Vref.
    Is this IAS or CAS or TAS?“
    Vref is usually in IAS. Especially since the occasion in which you are using it would be below 3000 feet AGL, and less than 200 knots.

| improve this answer | |
$\endgroup$
  • $\begingroup$ thank you so much for the help! btw for the heading/pitch changes, is there any exact number? ex 3 or 5 degree $\endgroup$ – rumput gajah Jun 24 at 15:52
  • $\begingroup$ Constant rate (vertical speed) descents and constant speed (airspeed) descents are very similar to straight & level, unaccelerated flight. A 1-3° adjustment/compensation is normal. A 3-5° adjustment/compensation is extreme, but not uncommon. Per my instructor, over 5° would be unstabilized. Over 10° would be a deviation from lateral or vertical guidance; lack of directional control; leveling off for a MDA, circling approach or missed approach; or, an actual missed approach or go-around. The rate and frequency at which you make these changes is also a factor. Your instructor may see different. $\endgroup$ – Dean F. Jun 24 at 17:23
  • $\begingroup$ thank you so much!!! $\endgroup$ – rumput gajah Jun 25 at 8:49

Not the answer you're looking for? Browse other questions tagged or ask your own question.