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Do any airline pilots refuse to fly, if wx is not below operating minima?

The question was

if wx is not below operating minima?

Freelance IRI / CB-IR Instructor
LOWG | Worldwide

Emir wrote:

Did you mean “if weather is below operating minima” of “if weather is not above operating minima” rather than “if wx is not below operating minima”? I’m not sure about terminology – the title sounds pretty odd to me.

The way it is written, I understand that Peter meant: “Do some PICs at airlines refuse to depart, even if all legal minimums are met?”.

Freelance IRI / CB-IR Instructor
LOWG | Worldwide

I think your wording creates confusing. There is never a situation in where your required to depart into a unsafe situation or another way to put it is that must be at least one 100 percent sure that the flight can be completed successfully.

The international Australian airline ;-) pushes this idea to the max AFAIK more so than some of their competitors. But they do have a lot of experience in long range remote operations.

Last Edited by Ted at 23 Nov 14:04

Let me try to cover each basic possibility of the question asked. I will assume we are ‘at departure’ for this.

Firstly, the final responsibility rests with the PIC, but as you alluded to, if I refuse to go flying in CAVOK every day, I won’t be PIC (or employed for that matter) for long.

If the departure weather is below operating minima for, I don’t go.
If the arrival weather is below operating minima, I will go with a suitable back up plan/more fuel.
If the departure weather is above operating minima, I go.
If the arrival weather is above operating minima, I go.

If for any of these cases the weather is around operating minima but a bit iffy, I will go with a back up plan/more fuel

Ops manuals for public transport (especially airline) tend to be fairly comprehensive. We generally have minima for most circumstances, be that runway braking action, thunderstorms in the area (ie. how many miles clear we must be), visibility or whatever else. One scenario they don’t explicitly cover (although ours do mention the possibility of it) are cumulative issues. Say for example we are flying somewhere with winter ops in place, runway is being cleared of snow often and the braking action is boderline, the vis is forecast to be very close to minima in heavy snow showers with bad winds, and we are carrying a couple of defects on the aircraft which increase our workload or decrease the capabilities of the aircraft. In this case it is down the the PIC’s judgement, but we aim to find a way to make things happen, so I don’t ring ops and tell them I’m not doing it and I’m going home. I ring them and tell give them my reasons for not being happy to operate. Maybe we can find a different aircraft that has no defects. Maybe we can delay departure by x hours etc.

In summary – we are expected to go if we can complete the flight from start to finish with everything being above minima. If certain parts are below minima we are expected to militate against the problems with that. If there are major problems then that’s when we might have to make a no-go decision based on the current situation and see if something can be changed. Our decisions will be backed up by the company if they are in compliance with the manuals and aren’t taking the mick.

United Kingdom

Not weather but:
A few years ago, Inverness area schools were due to fly for a skiing holiday. The kids and staff were at the airport. There was no weather issue.
The B757 diverted to Aberdeen, as the pilot was unhappy with the runway length. With no notice, buses had to be arranged to take everyone to Aberdeen Airport, almost 100 miles away, mainly on single carriageway.
The runway length was as published.

Maoraigh
EGPE, United Kingdom

Maoraigh was the runway at Inverness wet or contaminated? I spent most of my flying career on the 757 a truly amazingly capable aircraft.I have operated out of many short fields in it but on the day all factors have to be considered by the commander including his own currency experience and whether they have confidence that they personally can handle the forecast and actual conditions. I never had any pressure put on from management or operations to operate outside what I felt comfortable with …and I always enjoyed a challenge! Regards Stampe

United Kingdom

Very interesting!

Let me add a different Q: is a flight ever cancelled before departure because the return flight would be likely impossible?

I suppose this differs from a lot of such decisions in GA (which in GA are commonly no-go) in that most short haul return flight departures happen very fast after landing.

It would also be very interesting to know a bit about how tafs are interpreted in AOC ops. I was told many years ago that e.g. a PROB30 TEMPO of anything is formally ignored unless it is a persistent condition (fog, perhaps). I think the PROB30 / PROB40 (and no other % numbers) is directly to do with AOC procedures.

Administrator
Shoreham EGKA, United Kingdom
  • BECMG AT
    Average wind within limits. Gusts may be ignored.
  • BECMG FM, BECMG TL, BECMG FM…TL
    Worsening
    Average wind within limits. Gusts can be ignored.

Improving
Average wind within limits. Gusts can be ignored.

  • TEMPO, TEMPO FM, TEMPO TL, TEMPO FM – TL, PROB 30/40
    Worsening
    Passing/Shower conditions – N/A, average wind and gusts may be ignored.

Persistent conditions combined with haze, mist, fog, dust, sand & precipitation – applicable, average wind within limits. Gusts can be ignored.

Improving
Must be ignored

  • PROB TEMPO
    Worsening
    May be ignored

Improving
Must be ignored

Last Edited by Snoopy at 24 Nov 09:50
Freelance IRI / CB-IR Instructor
LOWG | Worldwide

Peter wrote:

I think the PROB30 / PROB40 (and no other % numbers) is directly to do with AOC procedures.

Exactly. I had always understood it as basically meaning:

PROB30 = possibly, but probably not

PROB40 = probably

It needs to have some binary element to it in order to allow consistent decision making. I don’t know why the 30% and 40% numbers were chosen, possibly as some representation of the risk threshold (risk of a divert) the airlines were prepared to take at some point in the past.

EGLM & EGTN

Peter wrote:

Let me add a different Q: is a flight ever cancelled before departure because the return flight would be likely impossible?

This would be extremely rare. Even more so with CAT3B equipment.
It would be a decision by operations control. They would factor in the cost of compensation to pax, rebookings, hotels etc..

For domestic (intra european) ops I had one cancellation due to freezing rain at LOWW over a couple thousand flights. All other flights we departed. Must add I never flew anything less than CATIIIA capable.

Freelance IRI / CB-IR Instructor
LOWG | Worldwide
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