Thorough pre-flight preparation the best defence against flying into deteriorating weather

Key points:

  • Student pilot and Instructor did not detect forecast deteriorating weather during their pre-flight briefing;
  • Pilots should maintain knowledge and skills required to avoid unintentional operations in IMC;
  • If a VFR-rated pilot does find themselves in marginal weather, they should seek whatever assistance is available, including contacting air traffic services.

 

An incident that saw a student pilot and instructor in a Piper PA-28 encounter deteriorating weather and enter instrument meteorological conditions (IMC) while operating under visual flight rules (VFR) highlights the importance of thorough pre-flight planning, an Australian Transport Safety Bureau investigation notes.

The student pilot (in the left seat) and instructor (in the right hand seat), with a second student pilot (seated in the rear) observing, were conducting a navigation training flight in the PA-28 from Melbourne’s Moorabbin Airport to Warrnambool in western Victoria and return on 25 February 2021, as part of the student’s integrated commercial pilot licence training.

After refuelling at Warrnambool the aircraft departed to return to Moorabbin in visual flight conditions, with the plan that they would return to Warrnambool if the weather deteriorated.

As the flight progressed, and as had been forecast, the weather deteriorated, and the instructor decided to divert to Cobden Airport to land and wait until the weather cleared.

However, visibility significantly reduced in rain, and the instructor, who held an instrument rating but had not conducted any instrument flying since a March 2020 proficiency check (and therefore did not meet the currency requirements for single-pilot instrument flight rules flights), took control of the aircraft and the decision was taken to return to Warrnambool.

As the aircraft approached Warrnambool, visibility continued to reduce and the cloud base began to lower. The instructor then initiated a climb into cloud and contacted air traffic control, which provided navigation assistance to an area free from cloud, issuing a heading to Avalon Airport.

The aircraft, which was certified for day and night VFR operations only, subsequently exited cloud about 10 nm south-west of Avalon Airport, with the flight then continuing to Moorabbin for an uneventful landing.

“The ATSB found that although the pilots had conducted a pre-flight briefing, they did not detect the forecast deteriorating weather in the Warrnambool area,” said ATSB Director Transport Safety Stuart Macleod.

“In addition, prior to departure from Warrnambool they did not assess the aerodrome forecasts for both Moorabbin and Warrnambool to ensure they were suitable destination airports.

“This probably resulted in them selecting Warrnambool as an alternate airport, despite the forecast temporary deterioration, and the aircraft encountering poor weather during the return to Warrnambool.”

Mr Macleod said weather related incidents continue to be a significant concern in aviation safety.

“The ATSB encourages pilots of all experience levels to develop and maintain the knowledge and skills required to avoid unintentional operations in IMC,” he said.

“And if a VFR-rated pilot does find themselves in marginal weather, they should seek whatever assistance is available, including contacting air traffic services.”

Mr Macleod said the ATSB’s ‘Don’t push it, Don’t go’ safety education campaign provides further information on the risks of VFR into IMC flight.

“Don’t push it, Don’t go’ highlighted three key messages: the importance of thorough pre-flight planning and having alternate plans, that pressing on where there is the possibility of entering IMC carries a significant risk of spatial disorientation, and the value of using a ‘personal minimums’ checklist to help manage flight risks,” he said. 

“Pilots without a current instrument rating should always be prepared to amend and delay plans to fly due to poor or deteriorating weather conditions, and not to push on.

“Thorough pre-flight preparation is the best defence against flying into deteriorating weather."

Read the report: AO-20-21-009 VFR into IMC involving Piper Aircraft PA-28, VH-FPS near Warrnambool, Victoria on 25 February 2021.

Last update 16 July 2021

Final report

VFR into IMC involving a Piper PA-28, VH-FPS, near Warrnambool, Victoria on 25 February 2021