ASN Wikibase Occurrence # 279207
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information
Narrative:Air New Zealand flight NZ60 had been cleared to Faleolo via a FALE arrival for an ILS runway 08. The approach was planned to be an autocoupled ILS, using a low drag approach profile. During descent the aircraft was established on the 15 nm arc as per the STAR procedure.
|Owner/operator:||Air New Zealand|
|Fatalities:||Fatalities: 0 / Occupants: 176|
|Aircraft damage:|| None|
|Location:||10 nm West of Apia-Faleolo International Airport -
|Nature:||Passenger - Scheduled|
|Departure airport:||Auckland International Airport (AKL/NZAA) |
|Destination airport:||Apia-Faleolo International Airport|
|Confidence Rating:|| Accident investigation report completed and information captured|
Approaching the localizer course at 2800 ft LOC was armed, and the autoflight system subsequently captured the localizer inbound course. During the turn on to the localizer the aircraft was decelerated and configured to Flap 1. APP was armed after localizer capture and the autoflight system captured the glideslope shortly after. The crew reported a rapid energy
increase, with speed increasing to near the flap 5 limit speed. To assist with energy control, while continuing to configure the aircraft for landing, the crew used speedbrakes and landing gear. The flight instrumentation glideslope deviation indicators displayed ‘on glideslope’ throughout the approach.
Shortly after landing flap selection the PF (Pilot Flying) noted an anomaly in DME versus altitude. Around the same time the PNF (Pilot Not Flying), while trying to establish visual contact with the airfield and runway, became aware that visual cues did not correspond with what was expected. The SP (Supplementary Pilot) also became aware of an anomaly in
aircraft position at approximately the same time as the two other crew members.
A go-around was commanded, initially climbing straight ahead followed by a climbing left turn, to pick up the 340 o radial FA VOR to rejoin the 12 nm arc for a subsequent approach.
This second approach was flown with careful attention to distance and altitude, using the published DME recommended altitudes as per the LOC (GS out) table on the approach plate for glidepath management. The glideslope deviation indicator also indicated on glideslope throughout the second approach. The glideslope indications were ignored and the approach continued to a successful landing.
After reviewing their fitness for duty following the event, the crew elected to continue the tour of duty and return to Auckland. An autocoupled approach back into Auckland, closely monitored by the FMC profile, was normal.
The Flight Data Recorder was removed from the aircraft, and Air Traffic Control at Faleolo was requested to issue a NOTAM stating that the glideslope was unserviceable.
Subsequent analysis of the FDR information established that the aircraft had descended on a glide path of approximately 3.5° to a point approximately 5½ miles short of the runway with ‘normal’ localizer and glideslope indications displayed on the flight instrumentation.
It was later established that the ILS glideslope transmitter had inadvertently been left in control (monitor) bypass mode, with the unserviceable transmitter selected. In the bypass mode, the glide path transmitter executive monitor was unable to shut down the faulty transmitter or to transfer to the serviceable transmitter. The result was the radiation of invalid glideslope information consisting solely of the carrier plus side bands (CSB) signal component. The side bands only (SBO) signal component was missing from the glideslope transmission.
| || |
|Investigating agency: || |
|Status: ||Investigation completed|
|Download report: || Final report|
Other occurrences involving this aircraft
|9 Jun 2011
||Air New Zealand
||Auckland International Airport (AKL/NZAA)
The Aviation Safety Network is an exclusive service provided by:
CONNECT WITH US:
©2023 Flight Safety Foundation