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Airmann
17th Jul 2019, 07:54
Hi guys, I would like to get your take on the topic of thunderstorms around the final approach.

I have found that a number of pilots like to get below the cloud base as early as possible it the cloud base vs MSA allows that. Even so would you ever fly under the red of a CB? Is this even a good strategy anyway?

Do you have any limit on how close a CB could be to the airport for you to decide to shoot the approach (Assuming the final approach is clear)?

Thanks

sonicbum
17th Jul 2019, 08:45
Hi,

have a look at Airbus_Safety_first_magazine_22 (https://www.airbus.com/content/dam/corporate-topics/publications/safety-first/Airbus_Safety_first_magazine_22.pdf), from page 24 there is a lot of valuable information covering your questions and not necessarily Airbus related.

B2N2
17th Jul 2019, 11:03
Angle the radar up 10 degrees and I do t fly under red/magenta.
Wind direction and storm movement?
Published missed approach clear or not?
Alternate escape route that allows to stay in VMC conditions?
Iíve done visual approaches with an alternate missed approach coordinated with ATC prior to commencement.

ACMS
17th Jul 2019, 14:24
Fly under the base of a red cell????

NO.

safetypee
17th Jul 2019, 14:28
If you have doubts about an approach don’t do it; wait hold.
You cannot guarantee that the radar or even visual will detect a down-draft or outflow windshear.
If a Cb has been over the runway, allow 15 min for the runway to drain, otherwise use flooded runway landing performance.
https://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/media/2019/SAFO19003.pdf

Heed the advice of those who survived.
https://www.dropbox.com/s/12k90qtpqfu9evu/Windshear.pdf?dl=0

Dont Hang Up
17th Jul 2019, 14:43
Fly under the base of a red cell????

NO.
Isn't the argument that, once below cloud base, it is easier to see and avoid? Not that it is somehow safer to fly under rather than through.

gearlever
17th Jul 2019, 14:46
Angle the radar up 10 degrees and I do t fly under red/magenta.
Wind direction and storm movement?
Published missed approach clear or not?
Alternate escape route that allows to stay in VMC conditions?
Iíve done visual approaches with an alternate missed approach coordinated with ATC prior to commencement.


"Iíve done visual approaches with an alternate missed approach coordinated with ATC prior to commencement.".

Yep. I have done this many times at busy airports. 99% success while others diverted. Just coordinate with ATC. If you say "due to weather" local noise abatement procedures are voided.

safetypee
17th Jul 2019, 15:41
B2N2, gearlever,
Because you have done something before without event, does not change the inherent risk in the operation, thus never assuring success in the future.
The pre approach assessment is that of the risk in the plan depending on what is seen (or not seen) and judged as a justifiable course of action - what if this doesnít work out.
Itís a judgement - yours and should not assume too much about anyone elseís involvement including the operational pressures such as a busy airport.

vilas
17th Jul 2019, 17:55
There is no flat yes or no. D191 L1011 at DFW on approach when passing through a single CB encountered a severe microburst and fatally crashed. That accident led to development of predictive winds sheer.​​​​​ All CBs are not same. If the CB is well developed with top closer to 30000 then it's dangerous and best avoided.

jimjim1
18th Jul 2019, 03:51
Accident: Miami B738 at Jacksonville on May 3rd 2019, runway overrun on landing, aircraft ends up in river (http://avherald.com/h?article=4c780245&opt=0)


http://avherald.com/img/miami_b738_n732ma_jacksonville_190503_4.jpg

Check Airman
18th Jul 2019, 06:15
In Florida, we get thunderstorms all summer long. The ATC here are top notch, and can seemingly thread a needle through the storm cells, and find a generally smooth ride.

My airline has provided us pretty good guidance on operating when there are storms by the field. One thing we like to do is carry a comfortable amount of fuel for the inevitable hold. (8-11,000lb of planned arrival fuel is not uncommon for an afternoon arrival in an A319/320/321). That being said, if there's a large cell on final, we'd rather land with a tailwind, with alternate missed approach instructions, than fly under the red.

TOGA Tap
18th Jul 2019, 06:33
Do not take-off or land when thunderstorm is above the airport. Basic rule.

FullWings
18th Jul 2019, 06:55
I think there are many categories of storm, each with their own characteristics and risks. What level of maturity the cell(s) have, the environmental lapse rate, humidity, depth, etc. The effects range from benign to lethal.

If you can actually see whatís going on and combine that with the radar picture, it is possible to manage the risk but it takes a lot of experience, knowledge and readiness to throw it away if you donít like it. As per the previous poster, a storm over/proximate to the airfield is generally worth holding off for. On my type a lightning strike needs ~6 engineer hours of checking before it returns to service, so waiting 20mins for the storm to dissipate is cheap insurance...

safetypee
18th Jul 2019, 09:45
“During the approach the crew lost situational awareness, with their attention channelised, and the aircraft entered the storm cell with heavy rain after passing the MAP. The PIC did not arrest the excessive rate of descent, and flew the aircraft increasingly below the Glideslope.”
From http://www.aic.gov.pg/pdf/FinRpts/2019/AIC%2018-1004%20P2-PXE/P2-PXE%20AIC%2018-1004%20Final%20Report.pdf
https://www.pprune.org/showpost.php?p=10521394&postcount=276

B2N2
18th Jul 2019, 13:01
B2N2, gearlever,
Because you have done something before without event, does not change the inherent risk in the operation, thus never assuring success in the future.
The pre approach assessment is that of the risk in the plan depending on what is seen (or not seen) and judged as a justifiable course of action - what if this doesnít work out.
Itís a judgement - yours and should not assume too much about anyone elseís involvement including the operational pressures such as a busy airport.

Iím not sure what youíre trying to say here.
If you approach it as something ďyouíve done it many times beforeĒ then that attitude is wrong.
If you approach it as a challenge unique to that set of circumstances then youíre simply being a professional.
By doing this you develop a skill set.

safetypee
19th Jul 2019, 09:06
B2N2,
Your appropriate professional view is only one of a range of outcomes dependent on how experiences in challenging situations are used. Risks assessed and adequately mitigated, the exposure reviewed and memorised, can contribute to professional expertise - professionalism.

Alternatives include inadequate risk assessment and mitigation, but with an acceptable outcome the exposure could be stored as a valuable lesson learnt (donít do that again), or as an overconfident self-assessment of future ability. The latter is a powerful human bias - egocentric bias, also confirmation bias, choice supportive bias.

In an anonymous forum we cannot determine which of the outcomes is being related without further explanation, thus the reader could be adversely influenced if less adequate posts are taken at face value.
Question #1 represents an alternative approach, requesting information and explanation.
Statements of ĎI have done that beforeí do not relate the actual situation to the experience gained, or the personal attitude of the poster - training capt or troll.
Biased memories can be hazardous because an unwary newbie could be adversely influenced.

Many posts in forums are opinion - Ďopinion is the lowest form of human knowledgeí Bill Bullard
In addition ďIím entitled to my opinionĒ is used to shelter beliefs that should have been abandoned. It becomes shorthand for ďI can say or think whatever I likeĒ. ďYou are not entitled to your opinion. You are only entitled to what you can argue for.Ē https://theconversation.com/no-youre-not-entitled-to-your-opinion-9978

My humble, argued, opinion.

B2N2
19th Jul 2019, 10:04
So whatís your point?
Question was posted and I gave an answer and without any knowledge of my background and experience youíre calling that unsafe.

Yaw String
21st Jul 2019, 14:48
Our lot stipulate not to continue an approach if visibility reduces to 2000M or less in rain,when associated with presence of CB.
Slightly off the original post subject,but idea is to avoid likelihood of flooded runway associated with tropical downpour,and therefore,possibility of aquaplaning..

gearlever
21st Jul 2019, 15:41
Our lot stipulate not to continue an approach if visibility reduces to 2000M or less in rain,when associated with presence of CB.
Slightly off the original post subject,but idea is to avoid likelihood of flooded runway associated with tropical downpour,and therefore,possibility of aquaplaning..

Must be an operator with an amazing safety record:\

Smythe
21st Jul 2019, 21:58
In Florida, we get thunderstorms all summer long. The ATC here are top notch, and can seemingly thread a needle through the storm cells, and find a generally smooth ride.

Concur...I was driving with the Panasonic/Avtech system onboard as well, which provides FMS winds thorough the IFE system ...

sharing winds through the network....golden.

RVF750
22nd Jul 2019, 16:14
I've seen some pretty huge CBS in the area of the airfield I used to work at. Again, ATC were very good at co-ordinating, we'd land in from the clear end and depart away from the storms. 3,400m runway helps. Make-your-own missed approaches also agreed when needed from them.

zoigberg
22nd Jul 2019, 18:27
Airmann
while not necessarily directly addressing your question, I found this discussion below one of the more thought provoking on the general use of weather radar
https://forums.jetcareers.com/threads/weather-radar-techniques.35839/

There is some discussion on page 1 on Archie Trammel’s advice (radar guru, recently passed away), and further on some actual input from the great Dave Gwinn (even more radar guru, also passed away unfortunately).

It may may help you to decide if people going under red on final are riding their luck or actually making a reasonable judgment.

ManaAdaSystem
2nd Aug 2019, 09:54
A TS is a CB, but a CB is not necessarily a TS. The WX radar detects precipitation intensity, so a red cell can be whatever.
To fly through a red cell is not very unusual. BOM in the monsoon season has a CB/TS on final to runway 27 nearly all the time. Everybody flies through it.
Itís about reading the whole wx picture. Cloud tops? Lightning? Just rain? What do you do if the radar shows red from from one end to the other?
I have once flown through a micro burst. Not fun. In that case the wx radar showed green/yellow with some small red dots. No real red flags, but there it was. Massive rain, so hard we could barely hear each other. The aircraft kept flying. Just.
Iím amazed the engines kept working, but Iím still here.

ScepticalOptomist
2nd Aug 2019, 12:00
A TS is a CB, but a CB is not necessarily a TS. The WX radar detects precipitation intensity, so a red cell can be whatever.
To fly through a red cell is not very unusual. BOM in the monsoon season has a CB/TS on final to runway 27 nearly all the time. Everybody flies through it.
Itís about reading the whole wx picture. Cloud tops? Lightning? Just rain? What do you do if the radar shows red from from one end to the other?
I have once flown through a micro burst. Not fun. In that case the wx radar showed green/yellow with some small red dots. No real red flags, but there it was. Massive rain, so hard we could barely hear each other. The aircraft kept flying. Just.
Iím amazed the engines kept working, but Iím still here.

Please tell me who you work for so I may avoid them in my travels.

You claim to be surprised that you didnít crash after flying through a microburst but also say everyone flies through CBs on approach.

Where I am from we would not make an approach, and Iím never surprised that we didnít crash.

ManaAdaSystem
2nd Aug 2019, 15:59
Please tell me who you work for so I may avoid them in my travels.

You claim to be surprised that you didnít crash after flying through a microburst but also say everyone flies through CBs on approach.

Where I am from we would not make an approach, and Iím never surprised that we didnít crash.

Read again. We had no idea we had a microburst ahead of us. Nothing on the radar gave us a warning. No big red cells, and this was before PWS.
In the case of BOM runway 27, yes, everybody goes through that CB.
And there can be big variations between CBs.

ScepticalOptomist
3rd Aug 2019, 10:25
Read again. We had no idea we had a microburst ahead of us. Nothing on the radar gave us a warning. No big red cells,

There was warning, you said:


I have once flown through a micro burst. Not fun. In that case the wx radar showed green/yellow with some small red dots.


As you said in your earlier post - you need to look at the big picture - a microburst wonít show up on the radar. It also wonít be present unless thereís some serious weather in the vicinity - donít necessarily have to fly through a CB..

Again, please tell me which carrier it is so I can avoid flying with you.

Smokey Lomcevak
3rd Aug 2019, 11:48
Whilst weíre on the topic of BOM and CBís - an alternative question if I may...

Iíll be heading there tomorrow - although ts not my first visit it will be the first time Iíve been during the wet monsoon. Does anyone have any experience of opting not to fly through a CB on final when everyone else is? In my experience local ATC are generally good - but as I say Iím yet to go when conditions are a little more adverse... Any other top tips welcome too - how does the runway state hold up?

Thanks in advance...

felixthecat
3rd Aug 2019, 12:18
Whilst weíre on the topic of BOM and CBís - an alternative question if I may...

Iíll be heading there tomorrow - although ts not my first visit it will be the first time Iíve been during the wet monsoon. Does anyone have any experience of opting not to fly through a CB on final when everyone else is? In my experience local ATC are generally good - but as I say Iím yet to go when conditions are a little more adverse... Any other top tips welcome too - how does the runway state hold up?

Thanks in advance...

Having flown extensively throughout Asia, and indeed the world, just because someone else is flying through the CB doesnít mean you should. If your not happy with it just dont do it, peer pressure is a dreadful thing. Have the courage of your convictions and wait it out. Take extra fuel in Asia in monsoon for sure....

sonicbum
3rd Aug 2019, 14:50
Whilst weíre on the topic of BOM and CBís - an alternative question if I may...

Iíll be heading there tomorrow - although ts not my first visit it will be the first time Iíve been during the wet monsoon. Does anyone have any experience of opting not to fly through a CB on final when everyone else is? In my experience local ATC are generally good - but as I say Iím yet to go when conditions are a little more adverse... Any other top tips welcome too - how does the runway state hold up?

Thanks in advance...

Assess the weather while You are descending and check where the big no-go stuff is located by optimum use of your wx radar. In tropical regions You may well fly the whole final approach with the weather radar showing red till the runway because of heavy rain coming from a dissipating cell with no danger of microburst, windshear or hail. If You had scanned prior the approach that this very same cell was something going up to 40+ thousand feet then with the same (or very similar) weather radar picture it would be a no-go. The key point is to have the picture while you're still high descending and still have many options. Once you are satisfied with the analysis you can decide whether it's a go or hold.

misd-agin
3rd Aug 2019, 15:31
As Sonicbum mentions in high moisture areas the entire radar screen can be red. A TS isnít 40 nm by 40 nm but thatís what the radar display will show.

The newer radars that allow you to desensitize the radar returns helps.

If if you donít have a newer radar, that allows desensitization, remember the overall radar image at top of descend, or lower, before the entire display goes red.

Years ago descending into a tropical storm I had a senior CKA/training manager on the Jumpseat. I mentioned Ďred out.í Heíd never heard of it (they donít fly as much as regular line pilots) and was skeptical. At altitude it was obvious, both with the naked eye and radar, that a big cell was over the final waypoint of the STAR. After descending into the heavy moisture the TS return was lost as the entire screen turned red. We deviated around the known weather based on its location from the radar display before it went entirely red.

Today it might be worth using your camera to take a picture of the radar display. Fortunately the vast majority of our fleet has the improved radars that allow desensitization.

Phone cameras as can also be used to view a dim radar display in bright light. Put you camera lens so that it displays the ND or particularly a radar return. It greatly increases the brightness of the ND display.

swh
3rd Aug 2019, 22:43
A TS is a CB, but a CB is not necessarily a TS. The WX radar detects precipitation intensity, so a red cell can be whatever.


it is easy to tell those who fly through rain regularly and those that donít. Green on a wx radar just means 4 mm/ hr or less rain, yellow between 4 and 12 mm/hr and red > 12 mm/hr. 12 mm of rain per hour in the tropics is not unusual and does not indicate a TS alone.

Pilots need to be able to use tilt, gain and mode. They need to effectively use manual gain, Wx Turb, and tilt.

Boeing and Airbus have no technical objection to flying through rain or landing when itís raining.

Check Airman
3rd Aug 2019, 23:57
Boeing and Airbus have no technical objection to flying through rain or landing when itís raining.



Some pilots do, though. Not sure where the fear comes from.

Global Aviator
4th Aug 2019, 00:48
I’ve held on a 15nm final to wait for a CB with sparks coming out of it to move away as it was between us and the runway.

At the same time two other aircraft went straight thru.

Held for 8 mins, then a beautiful smooth approach.

Each to their own!

:)