B777 flight crew reports descending below charted altitude on the LIMKO1 arrival to llbg which is de...

Attributes
ACN	1237840
Time
Date	201502
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B777 Undifferentiated or Other Model
Flight Phase	Final Approach
Route In Use	STAR LIMKO ONE
Component
Aircraft Component	MCP
Person 1
Function	Relief Pilot Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Deviation - Altitude Crossing Restriction Not Met Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy

Narrative:

I was an international relief officer (international relief officer) on the flight sitting behind the first officer (first officer). When we transitioned from the STAR to the arrival and cleared for the approach localizer directional aid (lda) rwy 30; 4;500 ft was displayed and I assume that the pilot flying (PF) must have pushed the altitude button; since the aircraft started to go down to that altitude. The problem was that it was about 2 miles prior to limko (IAF). I stated that we needed to be at 5;000 ft. Until we passed that point; but it was too late since the aircraft was already at 4;500 ft. The ATC stated that we should have been at 5;000 ft; but said that we could remain at 4;500 ft. Since; the visibility is limited from that jumpseat; I did not see how we came to be at 4;500 ft.; but I went off the voice call outs and thus made the remark that we needed to be at 5;000 ft; but it was too late.

Original NASA ASRS Text

Title: B777 flight crew reports descending below charted altitude on the LIMKO1 arrival to LLBG which is detected by one of the IRO's and ATC but too late to prevent the deviation.

Narrative: I was an International Relief Officer (IRO) on the flight sitting behind the First Officer (FO). When we transitioned from the STAR to the arrival and cleared for the approach Localizer Directional Aid (LDA) Rwy 30; 4;500 ft was displayed and I assume that the Pilot Flying (PF) must have pushed the ALT button; since the aircraft started to go down to that altitude. The problem was that it was about 2 miles prior to LIMKO (IAF). I stated that we needed to be at 5;000 Ft. until we passed that point; but it was too late since the aircraft was already at 4;500 Ft. The ATC stated that we should have been at 5;000 Ft; but said that we could remain at 4;500 Ft. Since; the visibility is limited from that jumpseat; I did not see how we came to be at 4;500 Ft.; but I went off the voice call outs and thus made the remark that we needed to be at 5;000 Ft; but it was too late.

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.

B777 flight crew reports descending below charted altitude on the LIMKO1 arrival to llbg which is detected by one of the international relief officer's and ATC but too late to prevent the deviation.