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Cecco
2nd Oct 2012, 20:20
At our homebase, we do tailwind landings/take-offs if within limits, no gusts, runway dry and no other traffic is present (C525). All items are properly briefed before opting for a tailwind/take-off landing. Landing or take-off downwind is, in our case, for convenience reasons.

Are you sometimes opting for tailwind landings, conditions permitting, for your convenience or are you absolutely against that?

Are prop-aircraft more affected (negatively) by tailwind then jet aircraft?
If so, why?

Cecco

S-Works
2nd Oct 2012, 20:28
I take off and land on the same runway 30 times a day in opposite directions in a turboprop. We can take 10kts up the chuff without problem.

Cecco
2nd Oct 2012, 20:54
Point taken but are there any factors on an aerodynamic level, which make a jet more suitable for tailwind operations than a prop aircraft?

Also I heard the statement: For a fast aircraft with moderate tailwand, landing with TW is no big deal whereas for a slow aircraft with tailwand at the limit, it could be disastrous. How come the fast aircraft should have less problems when landing with tailwind then the slow aircraft?

what next
2nd Oct 2012, 20:54
Every minute counts. So yes, if within limits I take the tailwind. Even in our little Citation a straight-in approach can save as much oil as I need to heat our house a couple of months (if I would heat with oil). Would be pretty stupid to throw that away, wouldn't it?
And no, propellers and jets are just the same in that respect, only the numbers may be slightly different.

You must be careful when flying to frequent destinations where you are well known, howewer. At one of my destinations, they will always give us the windspeed as 9 knots, so that we can choose ourselves which runway to land on...
Even a long runway can get pretty short when you land with xx knots from behind ;)

suninmyeyes
2nd Oct 2012, 22:03
If you are very comfortable with the aircraft and its performance and wish to avoid long distances taxiing it can sometimes be be commercially viable. However for most of us if we get it wrong it might be the end of our career.

Prince Charles tried it in a BAE 146 with a 12 knot tailwind into Islay in 1994....

http://www.mod.uk/NR/rdonlyres/65F3C701-0FE7-4086-80FA-EEF5242D2A13/0/maas94_01_bae_146_cc2_ze700_29jun94.pdf

Cecco in reply to you question about why a tailwind may be more punitive on a turboprop than on a jet. The only reasons I can think of are jets are better at dumping lift due more effective speedbrakes and a turbo prob has massive disking propellors in ground fine pitch which can act like a sail when slowing down with wind behind.

Cecco
2nd Oct 2012, 22:26
10 kts. Tailwind=20% additional landing distance (acc. AFM, additional landing distance varies between 17-20% (OAT, landing weight); 20% being the upper limit). We use the 20%-rule to do a quick maths when we get the
current wind by the tower (checking against the wind received in the ATIS).

tommoutrie
3rd Oct 2012, 13:58
Aren't you the same bloke that asked the question about which flap setting to use OEI? You never posted anything about it again and now you've lobbed another grenade to get everyone arguing. Are you flying this thing around single pilot or is there someone there you can go over these fairly basic things with? This isnt a great forum to find out how to fly because you will get all sorts of loonies answering your questions and you will get so many conflicting answers that you'll learn nothing.

what next
3rd Oct 2012, 14:16
... and you will get so many conflicting answers that you'll learn nothing.

I object! Maybe you don't learn directly from the answers given here. But I for example have taken the opportunity and reviewed the limitations and procedures of the airplanes I fly with regard to tailwinds and also to single engine landings. Sometimes it is good to be reminded to do this more often than on occasion of the yearly sim refresher.

Please keep asking "silly" questions! (But no silly answers...)

tommoutrie
3rd Oct 2012, 14:29
and thats great but have a look at the other posts he's made. He starts a bunfight over some load of waffle and then just loses interest. You're obviously quite sensible. You've read the top line and gone "ooh I've forgotten how that affects me" but there are a bunch of loonies who will pontificate on the fine points of tyre speeds and ground effect and climbing into a negative wind gradient and degraded 2nd segment climb gradients and all the while this bloke it constructing a post about whether its safer to fly an ILS inverted because you can see the ground more easily..

(hang on, that might be a good idea..)

Above The Clouds
3rd Oct 2012, 18:40
Cecco

Just follow the AFM, most manufacturers have a 10 kts limit for a reason.

Saving a minute or so for convenience makes no sense, this saving would be offset by increased tyre, brake wear and maintenance.

There is a valid use of tailwinds for obstacle clearance on departure or arrival say Innsbruck, Narsarsuaq etc subject to brake energy and climb performance limits which I trust you calculate and not just wing it, which I suspect from your post is what you are doing.

His dudeness
3rd Oct 2012, 18:56
He starts a bunfight over some load of waffle and then just loses interest.

Did he ? I thought it was my statement that started the controversial discussion...


On the topic, sometimes one can come quite close to the tire limits, even more so with a tailwind. I remember flying the C650 were you could come as close as (IIRC) 5 kts to max tire speed with a certain emergency (was that the stuck stabilizer?). Land on a TW runway and you might have a real problem.

Brake energy limits (as ATC already pointed out) might be another consideration especially when one lands and say, just drops a pax and then takes off again. 20 kts of groundspeed (10 HW vs.10 TW) can make a huge difference there...

tommoutrie
3rd Oct 2012, 23:24
you weren't contentious - you said "do what the manual says" (and then got ribbed for being and examiner and not knowing what a 2+ is ..)
The bloke keeps asking questions that get people going and then makes no further comment. If you start a thread on here surely you should be interested enough to participate. I mean this one is the same isnt it? Just use the perf charts and the limitations. I regularly accept a slight tailwind. Chambery, Annecy, Florence, and you just do the numbers or use FlugP or similar and a yes or a no drops out of the other end. Isnt that it?

Pace
4th Oct 2012, 00:51
Tommoutrie

There is nothing wrong in asking questions to generate discussion or in fact pose controversial answers to get others thinking and responding.

Aviation is one of the slowest moving occupations yet the fastest travelling occupation! slowest in the sense that it has always been done that way so should always continue that way regardless of any sense.

There are some crazy responses mine included :E but we usually come to a sensible conclusion in these discussions.

Think how boring life would be and these forums without a bit of color and controversy???
One of my favorite sayings " If you do not push the boundaries you will never find what lies beyond" Holds true for forum discussions as well as any other of mankinds endeavors.

His Dudeness

On the topic, sometimes one can come quite close to the tire limits, even more so with a tailwind. I remember flying the C650 were you could come as close as (IIRC) 5 kts to max tire speed with a certain emergency (was that the stuck stabilizer?). Land on a TW runway and you might have a real problem

Was it not 24/7s Citation 550 which landed at Edinburgh with control problems at over 200 kts (radar estimated TDS) and 40 kts over the tire limits?

Would anyone land at St Moritz with a tailwind considering the airport altitude and landing TAS?


Pace

Cecco
10th Oct 2012, 06:48
Max. tyre speed (165kts. Even with 10 kts. TW and max. landing weight, you will never exceed 120kts. GS) and brake energy limit (unless you land at LSZS in the summer) is not an issue for the C525. The heavier the aircraft, the more restrictive the limitations become.

Cecco
10th Oct 2012, 06:54
Citation C25A

Assuming temp. -10
LD, zero wind, 1000m
LD, 10kts TW, 1177m

His dudeness
10th Oct 2012, 07:40
Whilst you are not wrong Cecco, I have heard the story of 2 tires blown (the fuse plugs, not the tires themselfs) on a CJ2+ after two aborted takeoffs done shortly after another. So brake energy limits might not concern you by the book, still I wouldn`t completely disregard or forget about them.