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Once again, specific to Airbus, we would follow the flight director command bars because of SRS ( speed reference system ) which takes wind shear into account.
Video from inside A320 cabin as plane flies through severe thunderstorm.
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Wind shear: an invisible enemy to pilots? | Safety First
Weather plays a significant role in aviation safety and is regularly cited as a contributing factor in accidents or major incidents. Wind shear in the form of microbursts particularly, can be a severe hazard to aircraft during take-off, approach and landing.
I’m out of my seat grabbing a new pair of skivs
It might interest you to know that our A320/319 (and soon to be 321) can, and DO, use an increased VR as a windshear precaution. I flew the jet for 6 years. I'm very familiar with the "Bus".
We do not use balanced field. Critical difference between us and others. We have our performance calculated based on everything you use, including CG, weight, runway, wind, altitude, temperature, slope, second segment climb, and probably a few things I can't remember.
So, for today's takeoff in EWR, we had the following takeoff data: 22R/W (intersection takeoff with 10,150 feet remaining) Flaps 5, reduced thrust, packs on, 215,800#, temp 21C, wind 283/19, altimeter 29.62, CG 28.5% MAC. Assumed temp for thrust reduction: 63C. That's a big reduction in actual thrust, but we still had plenty of margin with that thrust reduction.
V1 - 147
VR - 151
V2 - 154
VR Max (based on runway limit weight) - 164.
That's a 13 knot add we can use for increased VR as a windshear precaution. We still meet V1 stop requirements, and we meet every other takeoff consideration like second segment and obstacle clearance.
In Denver a few days ago, our increased VR was 18 knots above actual VR (I had stated V2, not VR in my previous post).
We had nearly the whole value of the reported loss added to VR before we left the runway. We had it covered. Had we not been able to add that much, and had we not carefully briefed our considerations and precautions (our mitigation plan) - then I would've refused to take off as well.
But we can add that much. We can take that much extra flying. Even on the Airbus. So, we did. At max power, with increased VR, on 34L at Denver, we rotated at the 8 board. We had 8,000 feet of runway remaining. I suspect that the only reason we couldn't add more to VR had to do with maximum tire speed, rather than a stopping consideration.
And we are not prohibited from taking off until we get to 30 knots, or microburst alert.
So, while I respect your decision to refuse the takeoff with the reported shear - the way we calculate performance, and our ability to add speed as a precaution, allowed me a safe, viable, option to be able to fly with the reported shear.
It wasn't a microburst, it was regular shear, and we flew right through it, while still climbing, because of that difference in how we approach performance.
We do not use balanced field. Critical difference between us and others. We have our performance calculated based on everything you use, including CG, weight, runway, wind, altitude, temperature, slope, second segment climb, and probably a few things I can't remember.
So, for today's takeoff in EWR, we had the following takeoff data: 22R/W (intersection takeoff with 10,150 feet remaining) Flaps 5, reduced thrust, packs on, 215,800#, temp 21C, wind 283/19, altimeter 29.62, CG 28.5% MAC. Assumed temp for thrust reduction: 63C. That's a big reduction in actual thrust, but we still had plenty of margin with that thrust reduction.
V1 - 147
VR - 151
V2 - 154
VR Max (based on runway limit weight) - 164.
That's a 13 knot add we can use for increased VR as a windshear precaution. We still meet V1 stop requirements, and we meet every other takeoff consideration like second segment and obstacle clearance.
In Denver a few days ago, our increased VR was 18 knots above actual VR (I had stated V2, not VR in my previous post).
We had nearly the whole value of the reported loss added to VR before we left the runway. We had it covered. Had we not been able to add that much, and had we not carefully briefed our considerations and precautions (our mitigation plan) - then I would've refused to take off as well.
But we can add that much. We can take that much extra flying. Even on the Airbus. So, we did. At max power, with increased VR, on 34L at Denver, we rotated at the 8 board. We had 8,000 feet of runway remaining. I suspect that the only reason we couldn't add more to VR had to do with maximum tire speed, rather than a stopping consideration.
And we are not prohibited from taking off until we get to 30 knots, or microburst alert.
So, while I respect your decision to refuse the takeoff with the reported shear - the way we calculate performance, and our ability to add speed as a precaution, allowed me a safe, viable, option to be able to fly with the reported shear.
It wasn't a microburst, it was regular shear, and we flew right through it, while still climbing, because of that difference in how we approach performance.
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Just to let people know on BITOG, what pilots can do at their airline doesn’t mean other pilots can do it at theirs theirs ( same type ).
Can you provide a reference for that Airbus procedure from your airline please?
Been on the Airbus 15,000 hours, never seen anything in the FCOM about being able to increase Vr to specifically deal with wind shear nor is it in our sops which are based on Airbus recommendations.
Never heard of that before ( Airbus ) for wind shear.
Vr ( and V1 ) can change based on whether we use TOGA or FLEX ( reduced ) but thats got nothing to do with dealing with wind shear ( even though we need to go TOGA if wind shear below 1500 feet ).
I know the Airbus well , and there is nothing we have as pilots to allow us to increase speeds to deal with wind shear at least with the performance at our airline.
I will ask the Airbus chief pilot and report back.
Very sharp guy. Former test pilot, aeronautical engineer. Long training and checking background.
If we don’t have it but other airlines do, I will ask him why.
Funny how Airbus doesn’t mention anything about that in their wind shear information.
safetyfirst.airbus.com
Can you provide a reference for that Airbus procedure from your airline please?
Been on the Airbus 15,000 hours, never seen anything in the FCOM about being able to increase Vr to specifically deal with wind shear nor is it in our sops which are based on Airbus recommendations.
Never heard of that before ( Airbus ) for wind shear.
Vr ( and V1 ) can change based on whether we use TOGA or FLEX ( reduced ) but thats got nothing to do with dealing with wind shear ( even though we need to go TOGA if wind shear below 1500 feet ).
I know the Airbus well , and there is nothing we have as pilots to allow us to increase speeds to deal with wind shear at least with the performance at our airline.
I will ask the Airbus chief pilot and report back.
Very sharp guy. Former test pilot, aeronautical engineer. Long training and checking background.
If we don’t have it but other airlines do, I will ask him why.
Funny how Airbus doesn’t mention anything about that in their wind shear information.
Wind shear: an invisible enemy to pilots? | Safety First
Weather plays a significant role in aviation safety and is regularly cited as a contributing factor in accidents or major incidents. Wind shear in the form of microbursts particularly, can be a severe hazard to aircraft during take-off, approach and landing.
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I'll screenshot the relevant pages of the A320/319 FM and send it to you PM. Because it's company/proprietary, I'm not comfortable sharing it on the internet.Just to let people know on BITOG, what pilots can do at their airline doesn’t mean other pilots can do it at theirs theirs ( same type ).
Can you provide a reference for that Airbus procedure from your airline please?
Been on the Airbus 15,000 hours, never seen anything in the FCOM about being able to increase Vr to specifically deal with wind shear nor is it in our sops which are based on Airbus recommendations.
Never heard of that before ( Airbus ) for wind shear.
I know the Airbus well , and there is nothing we have as pilots to allow us to increase speeds to deal with wind shear at least with the performance at our airline.
I will ask the Airbus chief pilot and report back.
Very sharp guy. Former test pilot, aeronautical engineer. Long training and checking background.
If we don’t have it but other airlines do, I will ask him why.
Funny how Airbus doesn’t mention anything about that in their wind shear information.
Wind shear: an invisible enemy to pilots? | Safety First
Weather plays a significant role in aviation safety and is regularly cited as a contributing factor in accidents or major incidents. Wind shear in the form of microbursts particularly, can be a severe hazard to aircraft during take-off, approach and landing.
But increased VR is most certainly part of our Airbus precautions.
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Rest assured fellow BITOG members, behind the scenes a healthy, respectful, robust discussion is unfolding but it’s top secret.
I maintain my position.
I am referring to what Airbus recommends , not the airline or in-house performance engineering ( despite it being safe ).
When airlines follow recommend Airbus procedures, we are all on the same page restrictions wise pretty much. When different airlines have their own ( even if safe ) procedures approved by State regulatory authorities ( FAA, Transport Canada , Civil Aviation Authority , etc ) that differ from the manufacturer , it’s inevitable that one airline will be more/less restricted how they operate the same aircraft.
From what I saw, I am more restricted than an Airbus Captain at Astros airline when dealing with wind shear LLWS on take off.
Despite having 15,000 hours / 21 years on the Airbus, over 26,000 total time, I cannot take off with a LLWS loss of 20 knots.
Thats my point.
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Thanks for the Airbus article, having read it, it’s principally focused on microbursts.
I completely understand and support your point. Given how the FCOM (manual) is written, it makes sense.
I would completely support your decision to refuse in similar circumstances to mine.
I think it important, for those following the thread, to distinguish between microburst and simple (if there is a such a thing) windshear. Different animals. Both serious.
My case was windshear, on a windy day in Colorado, where the winds were calm on the ground and significant wind existed at a thousand feet. That caused the shear.
I’ve been in Colorado when virga, dew point spread, rain shafts, etc. all pointed to a high probability of microburst, and on some of those days, I’ve refused, and/or delayed, takeoff. Different scenario. Different threat.
I also, and perhaps this biased my decision, have great confidence in the excellent thrust/weight of a lightly loaded 757-200 with RB-211s. By adding the full expected loss on the ground, we were going airborne with an excess of airspeed equal to the expected loss, and with those RB-211s at full power.
When I’m at the Training Center next month, I’ll ask my fellow check airmen what they would do. I’m interested in other perspectives.
I completely understand and support your point. Given how the FCOM (manual) is written, it makes sense.
I would completely support your decision to refuse in similar circumstances to mine.
I think it important, for those following the thread, to distinguish between microburst and simple (if there is a such a thing) windshear. Different animals. Both serious.
My case was windshear, on a windy day in Colorado, where the winds were calm on the ground and significant wind existed at a thousand feet. That caused the shear.
I’ve been in Colorado when virga, dew point spread, rain shafts, etc. all pointed to a high probability of microburst, and on some of those days, I’ve refused, and/or delayed, takeoff. Different scenario. Different threat.
I also, and perhaps this biased my decision, have great confidence in the excellent thrust/weight of a lightly loaded 757-200 with RB-211s. By adding the full expected loss on the ground, we were going airborne with an excess of airspeed equal to the expected loss, and with those RB-211s at full power.
When I’m at the Training Center next month, I’ll ask my fellow check airmen what they would do. I’m interested in other perspectives.
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That Airbus article cautions pilots about loss of air speed. Losing more than 20 knots is dangerous regardless whether it comes from a microburst or wind shear. Thats why they do not recommend taking off in an Airbus ( not sure what Boeing says ).
Adding extra speed will mitigate that risk but only if your allowed to do it. Airbus doesn’t recommend adding extra speed. They recommend not taking off.
I do agree that microbursts are more dangerous because they can be much more powerful and less understood ( not many airports have the equipment to warn pilots ).
The purpose of the discussion at my end was just to point out what Airbus recommends for Airbus and that people on BITOG understand that just because other airlines ( same plane or different plane ) do stuff doesn’t mean others can.
Airbus supplies airlines with performance data that airlines can tailor to suit their needs ( performance and engineering dept ) but that doesn’t mean Airbus recommends it like with wind shear.
I am NOT implying it’s unsafe. I am just pointing out it’s not recommended.
Airbus definitely does not recommend adding extra speed on take off.
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Excellent discussion, gentleman.
As an A&P working at a heavy check facility, and not involved with line maintenance, I rarely get the chance to talk to the pilots about their experience flying.
Occasionally I get to ask them how their flights went when they drop an aircraft off for heavy check, and always appreciate it when they’re willing to share.
So, I really enjoy getting to “sit at the table” and listen to a very interesting and productive discussion between two highly-experienced airline pilots.
Thank you for being willing to let us in on your discussion!
As an A&P working at a heavy check facility, and not involved with line maintenance, I rarely get the chance to talk to the pilots about their experience flying.
Occasionally I get to ask them how their flights went when they drop an aircraft off for heavy check, and always appreciate it when they’re willing to share.
So, I really enjoy getting to “sit at the table” and listen to a very interesting and productive discussion between two highly-experienced airline pilots.
Thank you for being willing to let us in on your discussion!
How do you know what the plane weighs at takeoff? Is this just an estimate of baggage and passenger count added to the plane and fuel weight or does the plane have onboard scales or something?
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Thanks John.
I lurked here for years and only joined ( notice I never post anything on other sections, anymore ) to, hopefully, help members understand mainly Airbus stuff and offer my opinion at times.
I am not normally a forum type guy ( never been on any aviation forums or even company forum despite being asked to join ) but I like BITOG ( and it’s owner ) so I post here.
It can be addictive and takes up time but I enjoy it.
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Large airlines have a load department that handles that stuff.
After passenger boarding is complete, the agent calls load and advises how many passengers are on the flight.
After the ground crew finishes loading the aircraft , they call “ load” and tell them how many containers they loaded.
Load already knows how much fuel was boarded and then add it all up.
Load then sends us pilots ( using standard weights for bags and passengers except cargo ) the Final load report via a fax like machine ( ACARS ) in the cockpit.
We then independently cross check it and enter the weight into the flight management computer plus calculate our take off performance ( also independently checked ).
The ACARs prints off our max weight allowed, take off V speeds and power ( full thrust or reduced ).
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Relating to the load question above, thought this might be interesting despite wandering off topic.
What can happen when pilots are not careful ( not judging them ).
Some airlines have better procedures for catching gross errors.
They took off 200,000 pounds heavier than they calculated.
Lucky it was a long runway. Runway 16 is 12,000 feet long.
The other article talks about an Air France crew making the same mistake BUT noticed slow acceleration and applied full power.
www.flightsafetyaustralia.com
What can happen when pilots are not careful ( not judging them ).
Some airlines have better procedures for catching gross errors.
They took off 200,000 pounds heavier than they calculated.
Lucky it was a long runway. Runway 16 is 12,000 feet long.
The other article talks about an Air France crew making the same mistake BUT noticed slow acceleration and applied full power.
The finger of fate | Flight Safety Australia
One mistyped digit almost led to what could have been the worst crash in the history of Australian aviation. Adrian Park analyses an incident that exposes some uncomfortable truths about automation, redundancy and the role of human pilots. It was a busy Friday night at Tullamarine Airport as the
www.flightsafetyaustralia.com
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15,000 hours Airbus, around 26,000 total time.
I got hired with lots of experience and worked for around 10 companies ( most went bankrupt or laid me off ) before my current job. Most were smaller operations.
At most large airlines, with a mixed fleet, most pilots change aircraft more often than I do for a variety of reasons.
The larger the plane, the higher the pay for the same position ( CA/FO ).
I like being senior ( currently super senior ) so I chose to stay on the narrow body Airbus. I have spent my entire career ( except 2 when we went bankrupt and was forced down to the CRJ ) on the Airbus ( 21 years ).
I can hold Captain on everything we fly ( 330, 787, 777 ) but I would not be super senior, so I am staying put, for now.
Being super senior, I only work 8 days a month but I would work a lot more if I went on the wide bodies.
I am giving up lots of money but it’s not the right time for me to be working more and switching planes for family reasons ( 15 year old plus disabled, sick brother I see as much as a I can ).
My “plan” is to stay super senior ( so it doesn’t feel like work , fatigue wise ) on the narrow body and work until age 65 ( age 58 ) versus work 18 days a month and possibly not like work that much and complain about fatigue ( too many I know do complain on the WB but like the money ). They complain they work far too much despite loving the layovers and wide body operation.
I keep hearing the wide body operation is far more “civilized” than the narrow body operation.
Hope that offers some insight.
Edit: I have never been on reserve and fly high productivity trips ( I max out how many hours we can fly each year ). In Canada, we used to be allowed to fly more each year than U.S pilots.
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Go around is not an option...
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Correction on my flying hours, both total time and on the Airbus.
I have 24,020 total hours and 13,000 on the Airbus.
I decided to add up my logbook and ask the company how many hours I have flown on the Airbus.
My mental math was off because I forgot we didn’t fly much ( at all for months ) at all during the pandemic ( Canadian airlines ) from 2020 until fall 2021. Would have flown an additional 1000 hours.
23 years with the company but almost two years were a write off flying wise.
I have 24,020 total hours and 13,000 on the Airbus.
I decided to add up my logbook and ask the company how many hours I have flown on the Airbus.
My mental math was off because I forgot we didn’t fly much ( at all for months ) at all during the pandemic ( Canadian airlines ) from 2020 until fall 2021. Would have flown an additional 1000 hours.
23 years with the company but almost two years were a write off flying wise.
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