Video from inside A320 cabin as plane flies through severe thunderstorm.

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Astro,

The air traffic controller didn’t get the hint as to why the other aircraft were declining take off, not realize the cell in immediate area ?

Luckily the aircraft didn’t crash after take off climb.
 
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The wind shear and microburst reporting systems are all part of the network expansion upgrade to LLWS and TDWR systems. All of the core 30 airports east of the Rockies have them along with other strategic airports in frequent weather areas. LLWS sensors & TDWR algorithms work in unison to generate microburst alerts in real-time.
 
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Astro,

The air traffic controller didn’t get the hint as to why the other aircraft were declining take off, not realize the cell in immediate area ?

Luckily the aircraft didn’t crash after take off climb.

Don't think he will do that regardless. if he's overly cautious he'll be blamed for delays, if he's not cautious enough he gets blamed for crashes.

Now it's entirely on the pilots.
 

lurker

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Don't think he will do that regardless. if he's overly cautious he'll be blamed for delays, if he's not cautious enough he gets blamed for crashes.

Now it's entirely on the pilots.

I meant to say:

Doesn‘t the air traffic controller have an obligation to warn pilots of dangerous weather in the immediate area ?

I do understand that 99% of air traffic controllers are not even private GA pilots or ever been in a cockpit…..
 

lurker

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ATC is supposed to advise pilots of dangerous weather but not all ATC is able to see bad weather on their radar.

In the U.S, ATC can see adverse weather on their radar ( moderate to heavy/severe precipitation ) and will advise us like on my flight from Montreal to Florida last night ( lots of thunderstorms ).

Canadian ATC doesn’t have the proper radar to warn us.

When flying in the Caribbean or Mexico, you're on your own.

Over the ocean, ATC doesn’t have radar so your on your own ( they will ask us if we are aware of any “Sigmet” weather advisories and give us the general area if we don’t have it ).

Last night, U.S ATC was warning us about moderate to severe precipitation ( on their radar ) and “Sigmet” information about tornadoes.

We could see everything on our radar and had a smooth flight into FLL.
 
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Its unlikely that advisories were not issued in this situation, but I’ll let Astro speak to that.

As a general rule, yes, controllers have responsibility to broadcast all pertinent weather information to pilots as we deem necessary.

US enroute centers for example use networked NEXRAD radar feeds to display real-time weather in 3 intensity ranges. We can also display cross section altitudes for weather, ie: I can display weather from 0-FL600, or FL240-600, or FL330-600. It allows me understand what storms are at what height and issue as appropriate.

-“Moderate” precip equates level 2 storms, 30-40dbZ
-“Heavy” precip equates roughly level 3-4 storms, or 40-50dbZ
-“Extreme” precip equating level 5-6 storms, or simply greater than 50dbZ

We also each have a dedicated Center Weather Service Unit (CWSU) on site with a NWS meteorologist on duty who specifically handles the dissemination of all the AIRMET, SIGMET, and CWA advisories you hear us broadcast.

Most approach controls and their associated towers have even more detailed weather display from installed Terminal Doppler Weather Radar (TDWR) sites, as discussed above in the wind shear post.
 

lurker

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Our company policy says to be aware of possible microbursts even if not detected.
 

Astro14

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Our company policy says to be aware of possible microbursts even if not detected.
Sounds like that part of the operations manual was written by lawyers…

Microburst can kill you. Straight up. Windshear due to other causes can still kill you, but it’s not the massive downdraft that comes with a microburst, like the linked accident at Stapleton.

We actually encountered windshear on takeoff in Denver this past Wednesday. Gusty day. Nothing special beyond weird winds. LLWS (Low Level Windshear) advisories were published on ATIS (Airport Terminal Information System).

We carefully briefed our plan for Windshear - maximum thrust, flap setting, delayed rotation speed (calculated based on several parameters). Normal rotation for our weight, flap setting, winds, runway, and temperature that day was 151 Knots. The calculated maximum at which we could rotate with those conditions was 165.

Tower duly reported a “20 knot loss reported by previous aircraft” without particulars like altitude or distance from the runway. Their duty was discharged.

The decision rested with us.

We took off at max power (757-200 with RB-211s has quite a bit of extra thrust, so very nice). Rotated at 165.

At roughly 800 feet, the jet lost at least 20 knots. The GPWS (Ground Proximity Warning System) called out “Windshear! Windshear!”

We flew the escape profile, including max thrust, and the jet didn’t lose a single foot of altitude. My student FO was flying and did a good job of following the flight directors.

The precautions - power, flaps, and speed - all worked to make it a momentary event that didn’t affect us much.

We continued on to our destination.

I’m quite certain that our passengers, even our flight attendants, had no idea that we had encountered Windshear.

I had planned for it, I made a decision to go, and we were prepared. We consider, and then plan, for lots of things in aviation. This event clearly demonstrates why we do - that plan, and our preparation, kept us safe despite the threats presented by the weather.
 

lurker

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Sounds like that part of the operations manual was written by lawyers…

Microburst can kill you. Straight up. Windshear due to other causes can still kill you, but it’s not the massive downdraft that comes with a microburst, like the linked accident at Stapleton.

We actually encountered windshear on takeoff in Denver this past Wednesday. Gusty day. Nothing special beyond weird winds. LLWS (Low Level Windshear) advisories were published on ATIS (Airport Terminal Information System).

We carefully briefed our plan for Windshear - maximum thrust, flap setting, delayed rotation speed (calculated based on several parameters). Normal rotation for our weight, flap setting, winds, runway, and temperature that day was 151 Knots. The calculated maximum at which we could rotate with those conditions was 165.

Tower duly reported a “20 knot loss reported by previous aircraft” without particulars like altitude or distance from the runway. Their duty was discharged.

The decision rested with us.

We took off at max power (757-200 with RB-211s has quite a bit of extra thrust, so very nice). Rotated at 165.

At roughly 800 feet, the jet lost at least 20 knots. The GPWS (Ground Proximity Warning System) called out “Windshear! Windshear!”

We flew the escape profile, including max thrust, and the jet didn’t lose a single foot of altitude. My student FO was flying and did a good job of following the flight directors.

The precautions - power, flaps, and speed - all worked to make it a momentary event that didn’t affect us much.

We continued on to our destination.

I’m quite certain that our passengers, even our flight attendants, had no idea that we had encountered Windshear.

I had planned for it, I made a decision to go, and we were prepared. We consider, and then plan, for lots of things in aviation. This event clearly demonstrates why we do - that plan, and our preparation, kept us safe despite the threats presented by the weather.
When you say “max thrust” are you talking about pushing the thrust levers full forward ( firewall/over boost ) or just taking off with max normal thrust?

You took off with normal max thrust and then pushed full forward on the thrust levers when you got the warning?

Been a long time since I flew a non Fadec engine controlled plane ( B727 was the last one ) but the wind shear procedure was to firewall ( over boost ).

Does The 757 have FADEC?
 
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lurker

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I personally would not take off if told there is a 20 knot loss wind shear on the Airbus because we don’t have any method of increasing rotation speed to offset any loss of IAS due to wind shear. Plus, we are not supposed to ( if more than 15 knots ….company policy ) even though it’s the Captains call ( but not if a microburst is advisory ). Plus, I would get a call from our safety dept and flight ops If any wind shear warning goes off. They will know about it.

If a Tower reported a loss of 20 knots without any altitude, I would ask them to find out ( call departure to ask flight ). The take off ends at 1500 AGL and it would make the difference between not taking off and taking off on the Airbus ( no restriction after take off ).

Landing with a reported 20 knot loss of speed , the Airbus has a unique feature called “ groundspeed mini” ( constant energy state ) that is very effective in dealing with situations like that but we would still probably get a wind shear warning and have to do a go around anyways. Again, it’s preferred we hold or divert if a loss more than 15 knots is reported.

I guarantee folks that if your sitting in the front cabin of A320 and the wind shear warning goes off, not only will the front passengers hear it , but so will the flight attendants sitting close to the flight deck door.

When I dead head sitting up front, and I do not have the best hearing anymore , I can hear the auto pilot warning ( when pilots disconnect the AP ) going off.

I do the flying ( take off or landing ) when flying conditions are extremely challenging ( extremely strong crosswind etc ) . I have the most experience by a long shot.

I don’t interpret that part of the ops manual to be written by lawyers, I interpret it to mean the Captain doesn’t have to take off like the regional jet crew did in Orlando mentioned previously ( all the more experienced pilots were delaying take off even though no wind shear or microburst advisory was given unless I misread the thread ) even though nothing is mentioned by ATC that should concern them.
 
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lurker

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Found the answer I was looking for.

Has FADEC.

Disregard my previous question about firewall ( engines ). No big deal with FADEC.

RB211-535 series​

This is essentially a scaled down version of the -524. Its thrust range spans from 37,000 to 43,100 pounds. It powers Boeing 757 and is 180-minute ETOPSrated. The later series shares common features with the later series -524 such as wide-chord fan and FADEC.
 
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ATC is supposed to advise pilots of dangerous weather but not all ATC is able to see bad weather on their radar.

In the U.S, ATC can see adverse weather on their radar ( moderate to heavy/severe precipitation ) and will advise us like on my flight from Montreal to Florida last night ( lots of thunderstorms ).

Canadian ATC doesn’t have the proper radar to warn us.

When flying in the Caribbean or Mexico, you're on your own.

Over the ocean, ATC doesn’t have radar so your on your own ( they will ask us if we are aware of any “Sigmet” weather advisories and give us the general area if we don’t have it ).

Last night, U.S ATC was warning us about moderate to severe precipitation ( on their radar ) and “Sigmet” information about tornadoes.

We could see everything on our radar and had a smooth flight into FLL.

Thanks for the clarification and explanation. (y)

What aircraft are you flying ?
 
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Sounds like that part of the operations manual was written by lawyers…

Microburst can kill you. Straight up. Windshear due to other causes can still kill you, but it’s not the massive downdraft that comes with a microburst, like the linked accident at Stapleton.

We actually encountered windshear on takeoff in Denver this past Wednesday. Gusty day. Nothing special beyond weird winds. LLWS (Low Level Windshear) advisories were published on ATIS (Airport Terminal Information System).

We carefully briefed our plan for Windshear - maximum thrust, flap setting, delayed rotation speed (calculated based on several parameters). Normal rotation for our weight, flap setting, winds, runway, and temperature that day was 151 Knots. The calculated maximum at which we could rotate with those conditions was 165.

Tower duly reported a “20 knot loss reported by previous aircraft” without particulars like altitude or distance from the runway. Their duty was discharged.

The decision rested with us.

We took off at max power (757-200 with RB-211s has quite a bit of extra thrust, so very nice). Rotated at 165.

At roughly 800 feet, the jet lost at least 20 knots. The GPWS (Ground Proximity Warning System) called out “Windshear! Windshear!”

We flew the escape profile, including max thrust, and the jet didn’t lose a single foot of altitude. My student FO was flying and did a good job of following the flight directors.

The precautions - power, flaps, and speed - all worked to make it a momentary event that didn’t affect us much.

We continued on to our destination.

I’m quite certain that our passengers, even our flight attendants, had no idea that we had encountered Windshear.

I had planned for it, I made a decision to go, and we were prepared. We consider, and then plan, for lots of things in aviation. This event clearly demonstrates why we do - that plan, and our preparation, kept us safe despite the threats presented by the weather.

Isn't this always the case though? I like to have a plan ready to go in case of something out of the ordinary happening. Maybe you need it, maybe you don't but I like to know how I will cross that bridge before we get to it. Some just wing it.

Sometimes you encounter a situation where your plan B also doesn't cover it, but it's still better than not having a plan at all. maybe plan b just needs a little tweak to become plan C.

I hope (and don't doubt) your student FO realizes the planning is what saves the day, no matter how good you fly/drive/navigate etc....
 

wwillson

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the Airbus because we don’t have any method of increasing rotation speed to offset any loss of IAS due to wind shear.
I don't understand what you mean by "we don't have any method of increasing rotation speed". Why can you rotate at a higher speed than V2?
 

lurker

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I don't understand what you mean by "we don't have any method of increasing rotation speed". Why can you rotate at a higher speed than V2?
Thanks for the clarification and explanation. (y)

What aircraft are you flying ?
Thanks.

Currently, A319,320,321.

15,000 hours on type.

All take off and landing performance must be calculated ( no bush pilot flying, no winging it ) versus just thinking there is enough runway.

If it’s a gusty day ( landed in Florida Wednesday and Thursday night with Nicole ) and I wanted to add extra speed, Airbus says you can only add ( unless some technical failure ) 10 knots extra ( VLS + 15 = 10 IAS more ) and we have to run a landing calculation to verify we have enough runway.

Same goes for every take off. We enter the weight, OAT, pressure, wind, surface condition, flex ( reduced thrust ) or max power option, flap setting ( 1,2 or 3 ) , engine anti ice on or not and possibly AC packs off for more thrust.

If there is reported wind shear on take off ( take off ends at 1500 AGL ) , we cannot use reduced thrust. If the tower doesn’t say what altitude the wind shear was at, I ask them to find out ( always a way to find out because some flight reported it and they have to know what altitude it occurred at ). If they don’ t know, I would ask them to contact departure control to find out. If they cannot tell me, I get our flight dispatch to find out. If it’s more than 15 knots, no take off unless it’s above 1500 feet.

The aircraft ACARS will print off the take off performance that we MUST comply with. It will give us the max weight we can take off at, power setting ( flex temperature ) and take off speeds. V1 ( max speed can reject take off and have enough runway to stop ) , Vr ( rotation or lift off speed ) and V2 ( speed we fly after liftoff if we have an engine failure ).

We have to use those speeds and we are not given the option of adding extra knots to delay Vr so we never do. The only option is to use max thrust and less flap ( better climb ) if the runway ( supported by those same calculations ) is long enough. I would turn the packs off for better performance.

Let’s say I decided to just delay Vr by 15 knots ( long runway ) , I would not be complying with the take off data ( V1 calculations would be off now if we had to stop ) plus I could run the risk of having an even longer take off roll to get to Vr + 15 because of possible wind shear ( like that United B727 in Denver article above ) on take off While still on the runway. That’s why I want to know where the 20 knot loss of speed occurred also.

The V1 we calculate means we cannot stop ( safely ) above that speed and the take off must be continued ( unless the CA feels it’s safer to try and stop for some other reason they can justify ). We have only two seconds to decide whether to reject or continue at V1.




** I am not commenting on what other pilots do at other airlines because they might have take off performance calculation options ( and different lawyers lol ) but we cannot ever delay liftoff ( plan, brief ahead of time ) and add extra knots to V speeds on take off.
 
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lurker

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I don't understand what you mean by "we don't have any method of increasing rotation speed". Why can you rotate at a higher speed than V2?
Vr is rotation speed. V2 is only once in the air if lose an engine.
 

wwillson

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Please see above where I talk about it ( my aircraft type ).
Got it - not sure how I missed your great explanation above! Thank you.

Once off the ground you could push the nose down and bit and climb out at a higher airspeed, or is the climb speed a must as well?
 
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