As it was in the beginning:-
Find the time; listen, learn and think.
You might want to consider the flight forecast for the ATR flight in question.
The wind in the area was forecast to be from the west to north-west and increase with altitude from 30 kt at 7,000 ft to 60 kt at 14,000 ft. South of Canberra, the winds above 10,000 ft were expected to be up to 20 kt stronger. Turbulence was forecast to be moderate in cumulus cloud and moderate otherwise at all levels throughout the forecast area
At 1506, while the crew was en route to Canberra, another area forecast was issued. There was little substantive change to the weather outlook; however, winds were forecast to ease by 5-10 kt and turbulence moderate now above 10,000 ft rather than at all levels.
The aerodrome forecast (TAF)20 for Sydney Airport, which was valid from 1100 until 1700,indicated that the winds were 10 kt from the south-east. There was no mention of turbulence in the area.The TAF for Canberra Airport that was in effect for the flight from Sydney to Canberra and the departure from Canberra, indicated that the forecast winds were from the west at 16 kt. There was no mention of turbulence.At the time that the aircraft departed Sydney, the Canberra Airport aerodrome meteorological report (METAR), which had a trend type forecast (TTF) current from 1430, indicated that the winds were 15 kts, gusting to 26 kt from the west-north-west with no significant weather. However, at 1500, 6 minutes after take-off, a revised METAR/TTF for Canberra Airport was issued noting that there was moderate turbulence forecast below 5,000 ft.
However, the bureau went on to advise that the balloon flight suggested a relatively strong inversion was developing during the day of the occurrence. The aircraft would have been traversing from a warmer stable atmosphere into a relatively cooler and unstable layer between 7,000 and 10,000 ft. This could account for any reported moderate turbulence.
Take a look at Fig.16 in the report. - 05:40:42 to 05:40:57 = 15 seconds with a 22 knots to 8 knots ‘drop’ in wind – 14 knots – for 15 seconds. Hardly 'dramatic'. Anyone ever skipped off the top of inversion - at Red line:? How many FO's have been advised to back off the speed a bit? - to be sure - to be sure.
Find the time; listen, learn and think.
You might want to consider the flight forecast for the ATR flight in question.
The wind in the area was forecast to be from the west to north-west and increase with altitude from 30 kt at 7,000 ft to 60 kt at 14,000 ft. South of Canberra, the winds above 10,000 ft were expected to be up to 20 kt stronger. Turbulence was forecast to be moderate in cumulus cloud and moderate otherwise at all levels throughout the forecast area
At 1506, while the crew was en route to Canberra, another area forecast was issued. There was little substantive change to the weather outlook; however, winds were forecast to ease by 5-10 kt and turbulence moderate now above 10,000 ft rather than at all levels.
The aerodrome forecast (TAF)20 for Sydney Airport, which was valid from 1100 until 1700,indicated that the winds were 10 kt from the south-east. There was no mention of turbulence in the area.The TAF for Canberra Airport that was in effect for the flight from Sydney to Canberra and the departure from Canberra, indicated that the forecast winds were from the west at 16 kt. There was no mention of turbulence.At the time that the aircraft departed Sydney, the Canberra Airport aerodrome meteorological report (METAR), which had a trend type forecast (TTF) current from 1430, indicated that the winds were 15 kts, gusting to 26 kt from the west-north-west with no significant weather. However, at 1500, 6 minutes after take-off, a revised METAR/TTF for Canberra Airport was issued noting that there was moderate turbulence forecast below 5,000 ft.
However, the bureau went on to advise that the balloon flight suggested a relatively strong inversion was developing during the day of the occurrence. The aircraft would have been traversing from a warmer stable atmosphere into a relatively cooler and unstable layer between 7,000 and 10,000 ft. This could account for any reported moderate turbulence.
Take a look at Fig.16 in the report. - 05:40:42 to 05:40:57 = 15 seconds with a 22 knots to 8 knots ‘drop’ in wind – 14 knots – for 15 seconds. Hardly 'dramatic'. Anyone ever skipped off the top of inversion - at Red line:? How many FO's have been advised to back off the speed a bit? - to be sure - to be sure.