Flight below minimum incident highlights importance of conducing missed approach

Flight below minimum incident highlights the importance of conducing a missed approach

Key points:

  • During approach to Bankstown under instrument flight rules, a Piper PA-31P exceeded tracking tolerance and subsequently operated well below minimum safe altitude;
  • Pilot descended below cloud and declared themselves visual, before conducting two low-altitude orbits prior to landing;
  • Investigation highlights conduct a missed approach when necessary.

A pilot did not conduct a missed approach on two separate occasions while on an approach to land during which their twin-engined Piper aircraft exceeded tracking tolerance limits and they lost the required visual reference with the runway while operating below the approach minima, an Australian Transport Safety Bureau investigation details.

In the early afternoon of 22 March 2021, a twin-engined PA-31P-350 Mojave aircraft was conducting a positioning flight from Dubbo to Bankstown operating under instrument flight rules, with a pilot and crew member on board.

During a GPS instrument approach to Bankstown Airport’s runway 11C, the tower controller advised the pilot they were 0.5 NM south of the required track. This deviation continued as the aircraft passed the final approach fix, to the point it was exceeding tracking tolerance limits for the approach.

“The tower controller instructed the pilot to conduct a missed approach, but this did not occur,” ATSB Director Transport Safety Stuart Macleod said.

The pilot initially acknowledged that instruction but then requested, and was approved by the controller, to continue the approach visually as the aircraft had descended clear of cloud.

The pilot then conducted extensive manoeuvring, including two orbits, at low altitude and below the approach minima, that were not in accordance with the approach requirements, before landing the aircraft safely on runway 11C.

“The ATSB’s investigation into the incident found that the pilot did not conduct a missed approach when the aircraft exceeded the tracking tolerance limits, resulting in the aircraft operating significantly below the minimum allowable altitude,” Mr Macleod said.

“Additionally, having descended visually below the minimum descent altitude and commencing manoeuvring to position the aircraft for a landing, the pilot did not conduct a missed approach when the aircraft exited the circling area and the required visual reference with the runway was lost.”

Such manoeuvring was contrary to the intention of a circling approach, which is normally performed within the surveyed environment of the circuit area as part of visual circling to other than the straight‑in approach runway, Mr Macloed noted.

More importantly, when compared to the straight-in approach descent profile, it resulted in reduced obstacle clearance, increased pilot workload and an increased risk of an unstable approach.

“Adherence to operational procedures ensures consistency of pilot action and aircraft operation during the approach and landing phases of flight. This, along with careful monitoring of aircraft and approach parameters, ensures instrument approaches are conducted safely,” Mr Macleod said.

“If the criteria for safe continuation of an approach are not met, the pilot should conduct a missed approach to remove the risk of colliding with obstacles or terrain.”

You can find here the report: AO-2021-014 Flight below minimum safe altitude, Piper PA-31 Mojave, VH-XGW Near Bankstown Airport, New South Wales, on 22 March 2021

Last update 06 December 2021

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