Landing with a Tailwind
Posted by Former_Farm_3618@reddit | flying | View on Reddit | 57 comments
Hey 121 pilots, help us settle a bet at my tower. I’ve noticed a reluctance at my tower by some controllers to change runways due to winds. The pilots have occasionally asked us too. There sometimes is a 12-17 knot tailwind but the air carriers still land. I thought 10 was the limit, but another controller said it’s up to the Captain to decided to land, they just have to answer questions if anything goes wrong. Again, 121 carrier pilots, what’s your take if I read you “wind 090 at 17, runways 8R, cleared to land.” Can you legally accept this or do we NEED to change the runways? If it matters, we have mostly CRJ2/7 and B737 at my airport.
kbokwx@reddit
Experienced a go-around in a commercial plane last night (first time for me) and the pilot made a brief announcement that they had too strong of a tailwind to land - something they addressed by pulling up when the plane was less than a 100 ft above the runway and across the landing threshold. Boeing 737-700, WN 2442 HOU-OKC 1/16/25. I checked the METARs and the tailwind had increased during the hour from 6 kts to 10 kts, but shouldn't they have known that much earlier than just prior to touchdown? Ground speed on FlightAware bottomed at 153 kt. They did a loop and returned to the same runway going the opposite direction, ground speed much lower than that at touchdown going into the wind. So missed the approach due to airspeed but blamed the tailwind in this case?
Former_Farm_3618@reddit (OP)
The wind changes frequently. At my airport it can easily be a 7 knot tailwind now, in 20 seconds 15 knots then another 10 second 4 knots. The crew most likely was hoping it didn’t exceed the limit just before touchdown. It could have also kicked up a bit at that 100 feet and they decided to go around knowing the tower was changing runways right after them.
To get really nitty gritt, it’s not necessarily the airspeed they went around. They could have flown a very stable approach but if the steady tailwind was too much…you go around. Ground speed doesn’t matter as much as you think. Your indicated airspeed is basically the same regardless of the wind. However, if there are wind gusts then you add some wind factor. Where ground speed matters is your stopping distance. If you have a 10 knot tailwind vs a 10 knot headwind….thats a difference of 20 knots over the ground. That plays a factor is calculated stopping distance and is even more important when the runway is wet/icy.
kbokwx@reddit
OK, thanks for reply. For the record, above freezing temps and dry runway. All considered it was not a bad or frightening experience, just one of those "what was that? what went wrong?" feelings when they pulled up and powered up right when they'd normally flare slightly to touch down.
Working_Football1586@reddit
If you load the metar weather and it shows more than a 10 kt tailwind it wont give you any numbers for takeoff or landing.
changgerz@reddit
Anybody landing over their tailwind limit either is pretending they didnt hear you or they just dont care.
Going into ORD a few weeks ago they were landing west and the ATIS was reporting winds from the west. We were on about 8 mile final when the approach controller told someone else that they were changing to landing east and what the winds were (direct tailwind for the west runways at like 13 kt). of course we told him we could not land with that and had to go around. we werent exactly happy that they didnt tell us that the winds were basically opposite of what the ATIS said and in fact we might not have been able to safely and legally land on that runway even if we knew it and planned for it. but i guess god forbid we mess up their traffic flow right?
cmmurf@reddit
That's annoying as hell. The human recorded ATIS should get reported whenever there's a new METAR, and this kind of wind shift would have resulted in a special METAR.
I prefer the ATIS with hybrid bot+human recording. The bot part is METAR based, and the human part is the more static field information.
changgerz@reddit
its ORD, they are using D-ATIS
Former_Farm_3618@reddit (OP)
Okay, I kinda figured it was they don’t care. I really believe if you aren’t within legal limits we, ATC, should change. We have legal separation requirements and don’t allow pilots to bust those and get US in trouble. I’m still slightly baffled why pilots don’t all refuse when ATC tries to talk you into a bad plan. Thanks for your input
phalanxo@reddit
At my company the 737 is a 15 kt tailwind component limitation, however 10 is in use for some B737 operators as I understand it. Embraer 175 we had a 10 kt tailwind limitation.
LostPilot517@reddit
I have never heard of a blanket 15 knot tailwind limitation. Rather, I have heard of the standard 10 knot across the system, with approval for 15 knots at select airfields, San Jose, Costa Rica being one.
phalanxo@reddit
I mean ofc it's gonna vary by company. At my legacy it's 15 kt tailwind blanket for 737s and 757/767. Nothing specific to fields, but of course you have to have the legal data to do it, so it's not gonna work for SNA on a wet day.
JT-Av8or@reddit
It’s generally a limit unless there’s a specific allowance for that airport.
Eat-Sleep-Fly@reddit
Why are they reluctant to flip the runway???
639248@reddit
It takes work to change all the traffic flow. If you have other neighboring airports, then it has to be coordinated with them as well.
Eat-Sleep-Fly@reddit
I get that if the winds are light and variable.
But 17 knots.
639248@reddit
I agree, 17 knots definitely requires turning the airport around. But that doesn't change the fact that it takes a lot of work, and many people will do whatever they can to get out of work.
anonymous4071@reddit
I’m training on to my third type. CRJ, A320, and now the A220. All 3 had a 10 knot tailwind limit at the operators i worked/work for. Performance numbers may be even further restrictive in a wet runway or heavy jet scenario. If ATIS is reporting a 10 knot tailwind or greater, I’m asking for another runway. Hell i’ve canceled an approach around FAF because the winds exceeded the limit. I’m not risking plane, pax, crew, or my cert for convenience. Will some guys take a heavy wind? Yeah of course. I don’t like to play that game. Ask us if we’re able to take the tailwind if you’re concerned about it. We’ll let you know if we can’t
xxJohnxx@reddit
Interesting to hear that the 15kt tailwind limit (for TO and landing) is apparently not the standard on the A220, but rather an option our airline has chosen.
SeaHawkGaming@reddit
I would guess that’s the reason why it’s an FCOM supplement and not part of chapter 2 :P
anonymous4071@reddit
Also keep in mind we’re not talking total wind, but explicitly tailwind component. so a quartering 15 knot wind may actually be right at the limit of what we can accept. But anything straight down the runway over 10 knots from behind is not something i’ll be playing with
MassFlyGuy@reddit
As a 135 freight dog flying out of Denver, some of our outstations had only one approach (e.g. Rawlins, Wyoming). So if the weather is below circling minimums there, you're landing straight-in on 22 even with a tailwind. We were trained for this, and practiced landing with up to 25 knots tailwind. Good times!
andrewrbat@reddit
Limits are dependent on opspec, performance calculations, aircraft limitations, conditions, location specific limits, and pilot judgement. We limit ourselves to the most restrictive. Lots of airliners have a 10 kt tailwind limit but not all. The airbus 321 and maybe some other variants can do a 15 kt tailwind. I have landed a 321 in 15 kts of tw and it was not fun.
I refused to land in a 28 kt crosswind last week at iah because although the limit is 35, the braking action was 3-3-3 from rain and that reduces directional control ability on the runway. Thankfully the wind died down before we had to divert.
554TangoAlpha@reddit
CRJ and ERJ are 10 kt tailwind limits. Except in ASE where everything’s made up and the winds don’t matter.
CASAdriver@reddit
91k world, we always ask the pax if they prefer RIL or EGE, and take enough fuel to go to both. We don't even bother starting the approach if it's a 10+kt tailwind. If they shut down ASE, I'd buy a bottle of Dom Perignon
554TangoAlpha@reddit
Do you 91 guys use the instantaneous winds?
CASAdriver@reddit
We're authorized to use instantaneous winds from a page in the FMS to 100', or 200' in ASE. If it's strictly a 10kt tailwind we'll usually try, but any gusting or variability and it's not worth doing a low-altitude go-around in a valley. Easier and safer to go to RIL/EGE and have the company arrange transportation
MooneyDog@reddit
strange, our ERJs are 15kt tailwind. wonder whats different.
554TangoAlpha@reddit
Hmmm you might be right, been a minute.
MooneyDog@reddit
oh no worries. I was just curious if it was something like different winglets or weight that changed it to be so.
DinkleBottoms@reddit
The 175/170 at Envoy are limited to 10 knots tailwind. Probably an operator difference?
Former_Farm_3618@reddit (OP)
Oh yeah, ASE has some pretty crazy waivers from an ATC standpoint.
554TangoAlpha@reddit
It gives big “do whatever you want but if you fuck up it’s on you” vibes
FlydirectMoxie@reddit
“Captain, how much tailwind did you observe on your PFD/ND just prior to touchdown and sliding off the runway..? We can pull it off the FDR if you didn’t catch it..”
10 knots on the 777, 15 knots on the 300 model. No thanks, I’ll take another runway.
NotABidoof@reddit
At my operator, our software won’t even allow us to get landing data if the tailwind is greater than 10kts (aircraft limitation) so we couldn’t even if we wanted to.
StoutFlier@reddit
Our FOM states 10kt tailwind COMPONENT. If it’s above that, we can’t land unless we declare an emergency.
639248@reddit
Never seen more than a 15 knot tailwind limitation on a jet. It has always been either 10 knots or, in some cases, 15 knots. Any pilot accepting more than thing more than the published T/W limit is violating regulations (unless there is an emergency) and asking for all sorts of trouble.
redacted_post@reddit
I fly a cetain Seattle built 4 engine machine. All were delivered with a 10 kt tailwind limit. The check writers sent one with enough zeros and the majority of the fleet now can land with 15 kt tailwind.
However it doesn't like 1 kt let alone 15kt. Just give me a delay and turn the boat into the wind.
Kthxby
Solid-Cake7495@reddit
If you're operating outside of the limits set out in the AFM, you're not insured. Flying without insurance is illegal in most of the world.
49Flyer@reddit
Well, first of all 090/17 would be a headwind for 8R, not a tailwind, but to answer your main question the answer is it depends. While 10 knots is a very common tailwind limitation (and it is a limitation, not a suggestion) for transport-category airplanes there are exceptions. Some 737s are approved for tailwinds of 15 knots and when I flew the Dash-8 we were approved for 20 knots on the tail. Often it comes down to whether the company is willing to pay for the additional data, so it is common for different operators of the same aircraft to have different limits.
Even if the airplane itself is certified for the reported tailwind, performance can still be an issue. Depending on the runway length and obstacles in the go-around flight path, an airplane can be too heavy to land with a 10-15 knot tailwind even if it is within the "book" limitations.
Former_Farm_3618@reddit (OP)
Oh man, I didn’t proofread that example. Thanks for the info. So basically the CA is taking a risk by landing and not saying they need better wind..
49Flyer@reddit
Yes, although that risk is in most cases more legal than physical. 121 regs require landing performance to be based on 60% of the available runway length, so there is a fairly large fudge factor built in. That being said, if anything happened the crew (both pilots, not just the captain) would be held responsible for operating contrary to the limitations of the airplane and they wouldn't have a leg to stand on.
If I were faced with this scenario as a pilot I would 100% inform ATC that I am unable to land on the advertised runway. I suppose ATC doesn't need to change runways to accomodate me, but if they don't I'm going to my alternate.
SnazzySpaceman1@reddit
The 60% rule is for dispatch planning only. It is not required for your actual landing numbers. We can technically land if our data shows we will have a 1 foot stopping margin.
runaround713@reddit
I fly yellow A320s, and the tailwind limit is 10 knots for landing and 15 knots for takeoff. No exceptions.
Former_Farm_3618@reddit (OP)
Oh shit, 🤦. I ment let’s say a 17 knots was tailwind. Man it’s been a long day and I didn’t proof read.
Twa747@reddit
Ain’t noone but box haulers got time for that nonesense and even then
Turn the boat around boss I’ll go hold for a minute
Good-Cardiologist121@reddit
Unable.
redcurrantevents@reddit
I look at it this way: if I land with a tailwind over my airplane’s limit, and anything happens at all that requires them to look into my flight, I’m going to be asked why I intentionally violated a limitation on my aircraft. These are their airplanes, not mine, so I fly them the way the book says. I’ve gone around for 1 knot over the limit, and will every time unless I feel I could legitimately defend the statement “it was safer to land.”
Mithster18@reddit
The flight manual will have 1 number where (or their lawyers) has stated the max demonstrated Tailwaind.
The company SOPs will have another number which is probably less than number 1.
The pilot(s) will have a number they're comfortable with, which may be greater or less than 1 or 2. But if it's greater and something bad happens, then it's on the pilots to "please explain"
No legal requirement, but planes like as much head and as little tail as possible.
x4457@reddit
This is incorrect. The standard Part 25 airplane limitation is 10 knots and that's a hard limitation. Thou shalt not.
Some aircraft have a 15 knot limitation, a few have 20. But they're all hard limitations.
Mithster18@reddit
We don't have part 25 in my country.
Yes that's what I'm saying, the numbers in the flight manual are max demonstrated X/W or tailwind limitations. But the plane may physically be able to do more, but it's on the PiC's head whether they choose to do it.
x4457@reddit
Well, they're asking about the US (hence Part 121), and whatever jets are flying in your country also have Part 25 type certificates. And I promise you, in those type certificates, there is a maximum tailwind limitation.
You're saying maximum demonstrated. A max demonstrated and maximum limitation are not the same thing. Many/most airlines also have maximum crosswind limitations, though those are usually not AFM limitations.
554TangoAlpha@reddit
Uhhh what, we don’t just make up numbers and yes there are legal requirements. 787 max tailwind limit is 15. That’s a hard limit no way around it. However if it’s say only 12 kt tailwind we still may not be able to land if the landing performance is inadequate due to weight, wet, short, runway.
Former_Farm_3618@reddit (OP)
Interesting, I thought a flight manual or company SOP would be controlling and require a go around or missed approach. I guess I’ll stop telling my coworkers that 10 knot tailwind is too much??
x4457@reddit
They do, he's wrong. The aircraft will have a hard tailwind limitation.
extralegal@reddit
Based on aircraft limits and SOPs I would not be able to land, and would be asking for the other direction. (A320)
dyslecticr@reddit
Depends on the airline/airplane. At my airline on the A320 our limit is 15 knots for takeoff and 10 knots for landing.
rFlyingTower@reddit
This is a copy of the original post body for posterity:
Hey 121 pilots, help us settle a bet at my tower. I’ve noticed a reluctance at my tower by some controllers to change runways due to winds. The pilots have occasionally asked us too. There sometimes is a 12-17 knot tailwind but the air carriers still land. I thought 10 was the limit, but another controller said it’s up to the Captain to decided to land, they just have to answer questions if anything goes wrong. Again, 121 carrier pilots, what’s your take if I read you “wind 090 at 17, runways 8R, cleared to land.” Can you legally accept this or do we NEED to change the runways? If it matters, we have mostly CRJ2/7 and B737 at my airport.
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