In further on 2 August 2019, QF19 (1210 hours SYD - MNL) pushed back 33 late and should arrive at 1906, 36 late.
Identically timed QF107 pushed back 64 late at 1314 with PEK arrival suggested as 2306, 51 late.
Earlier, the SYD to SIN QF81 departed 19 minutes behind the timetable at 1029 with estimated arrival at gate becoming 1736, 46 late.
The projected departure of QF27 from SYD to SCL has further ballooned to 1430 meaning arrival at 1344, 159 late. In turn the overnight return flight, QF28, will be significantly delayed.
QF63 from SYD to JNB did not push back until 1315 hours, 140 late with forecast at gate arrival 1918 hours, 138 late meaning a delayed departure for tonight's QF64 ex the South African major centre. This is the third time in the last four trips that QF63 has been more than two hours late, a very poor situation if one has urgent meetings or personal appointments at the destination, or if one is connecting to a domestic (or other) flight in South Africa or Oz.
The causes of delay to these B744 flights are likely to be many and varied but while one can't be churlish in the absence of concrete information that there's poor maintenance - as most major airlines understandably regard safety as the priority - and many parts will have been renewed over the years, these ageing behemoths are experiencing more delays than was the case a decade ago.
I haven't looked at the rosters, but with the smaller number of QFi B744s, are they still more intensively used on Thursdays to Mondays in most weeks compared with Tuesdays in particular and Wednesdays to a slightly lesser extent?
QF51, the 1200 'high noon' BNE - SIN is often early off blocks, a creditable achievement, but on 2 August it pushed back at 1427. Expected arrival is 2027 tonight, 132 late. This was because yesterday, an aircraft must have failed in BNE as A332 VH-EBB operated QF126 from AKL, arriving BNE at 1801 hours, 19 minutes early and was then requisitioned to operate QF51 yesterday, taking off at 2042 mid evening and arriving SIN at 0215 this morning, 475 minutes tardy. It then ran QF52 from SIN down to BNE, becoming airborne at the unattractive time of 0359 hours and arriving at 1306, 421 minutes late.
So EBB has had a minimum turnaround in BNE of 81 minutes to again operate 'the 51.'
UPDATE: QF27 (B744 VH-OEI) departed SYD at 1432, 117 late but anticipated arrival has improved to 1310, 125 minutes behind the timetable. This should mean QF28 from SCL can be off blocks at around the 1455 hours mark.