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|
Attributes | |
ACN | 1202171 |
Time | |
Date | 201409 |
Local Time Of Day | 0601-1200 |
Place | |
Locale Reference | MMGL.Airport |
State Reference | FO |
Environment | |
Flight Conditions | IMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | A300 |
Operating Under FAR Part | Part 121 |
Route In Use | Vectors |
Flight Plan | IFR |
Person 1 | |
Function | Captain Pilot Flying |
Qualification | Flight Crew Air Transport Pilot (ATP) |
Experience | Flight Crew Last 90 Days 75 Flight Crew Total 8350 Flight Crew Type 3465 |
Events | |
Anomaly | Inflight Event / Encounter CFTT / CFIT |
Narrative:
We were on an assigned heading of 190; about 20 miles north of the airport; speed 200. Directed to maintain the 190 heading till passing the 090 radial off of gdl; then turn to intercept the localizer to runway 28. Cleared to 9000; speed now coming back to 180; flaps 15. We used both the RMI and nav display (with place/bearing/ distance) to monitor our position from the 090 radial. We also left the arc to RW28 displayed to further increase sa. Just as we approached the 090 to start the turn; ATC instructed us to turn to a heading of 260 to intercept localizer; then cleared for the approach; ILS 28. We were now IMC. Turned to heading of 260; saw that this was right at the marker and needed to get down quicker so that we were stabilized by 1000 AGL [after] the marker. Used speed brakes to maintain speed but increase vvi. Distance about 14 miles from airport. It was at this time that we got a 'too low; terrain' aural alert. As we were in the weather; over mountainous terrain and descending; I decided to perform a CFIT climbing maneuver (max thrust; wings level; ap and at off; speed brakes retracted). Only remember getting one alert; and almost immediately we were VMC and visually clear of terrain and we leveled at 9000. Initially we looked at salvaging the approach; but decided that the safest course of action was to get vectors back around for another ILS 28; due to the fact that I was already feeling a little on edge from the CFIT maneuver and thought it was best to let both the aircraft and myself get set up for another approach. The second approach was normal. Looking back after the approach; it looks like we were in the area east of the field; almost on final for runway 28 that took us over a peak of about 6400'. Add to this that I was using speed brakes to get down and I can see why it might have triggered the egpws warning. As things happened kind of fast and my main thought was of maintaining aircraft control and performing the CFIT; some of the details were not remembered; but this is as close as l can recall. Also; while not a major factor in this event; it happened at the very end of a long; two leg morning trip; so there was a probably a little fatigue that was setting in on both of us. A few things that I learned from this approach: 1) while the arc to final is normally displayed (and sometime flown); a lot of the time ATC will vector you to final for runway 28; which puts you inside the 16 DME arc; hence closer to the hills southeast of the field; instead of arcing just outside of them. This; plus the need to get down from about 9000 to a final altitude of 6200; is squeezing the parameters for a possible egpws event. 2) this is an approach that really needs to have as much data taken into account to get ahead and keep the needed situational awareness. Location; terrain; necessary descent rate (and closure rate to the hills); speed; and weather are all factors. This might be a very valuable learning experience for future simulator training. 3) while the company's special airport page has 'high terrain in all quadrants' listed under safety alerts; it might be a good idea to add something to this effect: due to possible ATC vectoring you off the arc and placing you on a heading to intercept final; it is possible to get an egpws activation during your descent from 9000 MSL down to GS intercept altitude; and to take both the descent rate and terrain into consideration when planning for this type of approach. Consider using flaps 20 and 160 kts to make this a more controlled descent to intercept the glide slope when in IMC.
Original NASA ASRS Text
Title: When the A300-600 flight crew was vectored to intercept the Runway 28 ILS final at MMGL as opposed to flying the full approach including the separate chart 16 DME arc transition to the 28 ILS; they opted to increase their rate of descent to avoid a potentially unstabilized approach. The higher closure rate that resulted was cited for an EGPWS generated terrain escape maneuver; which they performed and were then brought back around for an uneventful second approach and landing.
Narrative: We were on an assigned heading of 190; about 20 miles north of the airport; speed 200. Directed to maintain the 190 heading till passing the 090 radial off of GDL; then turn to intercept the localizer to runway 28. Cleared to 9000; speed now coming back to 180; Flaps 15. We used both the RMI and Nav Display (with place/bearing/ distance) to monitor our position from the 090 radial. We also left the Arc to RW28 displayed to further increase SA. Just as we approached the 090 to start the turn; ATC instructed us to turn to a heading of 260 to intercept localizer; then cleared for the approach; ILS 28. We were now IMC. Turned to heading of 260; saw that this was right at the marker and needed to get down quicker so that we were stabilized by 1000 AGL [after] the marker. Used speed brakes to maintain speed but increase VVI. Distance about 14 miles from airport. It was at this time that we got a 'Too Low; Terrain' aural alert. As we were in the weather; over mountainous terrain and descending; I decided to perform a CFIT climbing maneuver (max thrust; wings level; AP and AT off; speed brakes retracted). Only remember getting one alert; and almost immediately we were VMC and visually clear of terrain and we leveled at 9000. Initially we looked at salvaging the approach; but decided that the safest course of action was to get vectors back around for another ILS 28; due to the fact that I was already feeling a little on edge from the CFIT maneuver and thought it was best to let both the aircraft and myself get set up for another approach. The second approach was normal. Looking back after the approach; it looks like we were in the area east of the field; almost on final for Runway 28 that took us over a peak of about 6400'. Add to this that I was using speed brakes to get down and I can see why it might have triggered the EGPWS warning. As things happened kind of fast and my main thought was of maintaining aircraft control and performing the CFIT; some of the details were not remembered; but this is as close as l can recall. Also; while not a major factor in this event; it happened at the very end of a long; two leg morning trip; so there was a probably a little fatigue that was setting in on both of us. A few things that I learned from this approach: 1) While the arc to final is normally displayed (and sometime flown); a lot of the time ATC will vector you to final for RWY 28; which puts you inside the 16 DME arc; hence closer to the hills southeast of the field; instead of arcing just outside of them. This; plus the need to get down from about 9000 to a final altitude of 6200; is squeezing the parameters for a possible EGPWS event. 2) This is an approach that really needs to have as much data taken into account to get ahead and keep the needed situational awareness. Location; terrain; necessary descent rate (and closure rate to the hills); speed; and weather are all factors. This might be a very valuable learning experience for future simulator training. 3) While the company's special airport page has 'High Terrain in all quadrants' listed under safety alerts; it might be a good idea to add something to this effect: Due to possible ATC vectoring you off the arc and placing you on a heading to intercept final; it is possible to get an EGPWS activation during your descent from 9000 MSL down to GS intercept altitude; and to take both the descent rate and terrain into consideration when planning for this type of approach. Consider using Flaps 20 and 160 kts to make this a more controlled descent to intercept the glide slope when in IMC.
Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.