Downwind Landings

[Kyle Boatright]

What is your threshold for landing (or departing) downwind? Will you land
knowing you have a 5 knot tailwind? 10 knots? At what point will you
"flip" the pattern to takeoff or land into the wind?

Me? I'm a <5 knot kind of guy (but I fly a taildragger)...

I landed at 3 different fields today where the established pattern resulted
in a landing with a quartering 7 knot (or more) tailwind, with some mild
gusts thrown in for good measure.

At the first field, I was careless enough to assume the traffic was using
the runway facing the wind. The downwind landing came as a bit of a
surprise, then I looked at the wind sock - oops...

At the other two fields, I announced my position and intentions and waited
(360's on the downwind) until I could land into the wind without interfering
with aircraft already in the pattern.

And what is the correct radio phraseology to say: "Fellas, it is time to
reverse the pattern - you're taking off and landing downwind.." ?

[Andrew Sarangan]

On Sep 22, 11:01 pm, "Kyle Boatright" > wrote:
> What is your threshold for landing (or departing) downwind? Will you land
> knowing you have a 5 knot tailwind? 10 knots? At what point will you
> "flip" the pattern to takeoff or land into the wind?
>
> Me? I'm a <5 knot kind of guy (but I fly a taildragger)...
>
> I landed at 3 different fields today where the established pattern resulted
> in a landing with a quartering 7 knot (or more) tailwind, with some mild
> gusts thrown in for good measure.
>
> At the first field, I was careless enough to assume the traffic was using
> the runway facing the wind. The downwind landing came as a bit of a
> surprise, then I looked at the wind sock - oops...
>
> At the other two fields, I announced my position and intentions and waited
> (360's on the downwind) until I could land into the wind without interfering
> with aircraft already in the pattern.
>
> And what is the correct radio phraseology to say: "Fellas, it is time to
> reverse the pattern - you're taking off and landing downwind.." ?


One can easily do the math to get a ballpark figure. Landing distance
increases as the square of the approach ground speed. If the approach
speed is 60, and you have a 10 knot wind, your landing distance will
increase by 35%.For 20 knots it increases by 75%. For 30 knots, it
more than doubles. A 5 knot limit for short runways makes sense; 10
knots if you really know what you are doing. I would not atempt
anything higher unless it is a super long runway.

[Judah]

"Kyle Boatright" > wrote in
:

> What is your threshold for landing (or departing) downwind? Will you
> land knowing you have a 5 knot tailwind? 10 knots? At what point will
> you "flip" the pattern to takeoff or land into the wind?

It rather depends on the runway...

My threshold on a 3000' runway is smaller than my threshold on a 6000'
runway.

[Oz Lander[_2_]]

Kyle Boatright wrote:

> And what is the correct radio phraseology to say: "Fellas, it is
> time to reverse the pattern - you're taking off and landing
> downwind.." ?

This is the part I'm interested in hearing comments on.

--
Oz Lander.
Straight and Level Forum.
http://z7.invisionfree.com/Straight_and_Level/index.php?act=idx

[Larry Dighera]

On Sat, 22 Sep 2007 23:01:54 -0400, "Kyle Boatright"
> wrote in
>:


>What is your threshold for landing (or departing) downwind?

That is dependent on the length of the runway(s), its gradient/slope,
surface, and the performance of the particular aircraft.

>And what is the correct radio phraseology to say: "Fellas, it is time to
>reverse the pattern - you're taking off and landing downwind.." ?

The correct radio phraseology for operating at an uncontrolled field
is, Podunk airport traffic, Cessna 123 entering left downwind for
runway 18, Podunk traffic. Nothing changes. You self-announce your
intentions, keep your eyes open for conflicting traffic, and give
right of way in accordance with CFR 14 § 91.113 Right-of-way rules:
http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=ab913c45c8e61015448cb9ada7777b60&rgn=div5&view=text&node=14:2.0.1.3.10&idno=14#14:2.0.1.3.10.2.4.7

The tricky part of downwind landings is the necessity to extend your
traffic pattern's Downwind Leg (actually against the wind in the case
of a downwind landing) WELL BEYOND (perhaps double or more) what you
are accustomed to in a normal into-the-wind landing. If you fail to
do this, you will overshoot.

There's also the issue of whether to takeoff into or with the wind on
runways that aren't level....
http://groups.google.com/group/rec.aviation.piloting/msg/8bcc6adddb5951b5?dmode=source
An average force derivation gives the following formula for
the "breakeven headwind," i.e., the headwind of such speed that
it's a wash whether you take off into the headwind up hill or
take off with that tailwind down hill:

Vhw,breakeven = Slope in degrees * distance to lift off with
no wind, no slope / (5*speed at lift off in KTAS)

where Vhw,breakeven is in knots and the distance to lift off
is in feet.

With the same "constant" average force assumption the same
should be true for landing, making obvious changes. In actual fact
the above formula is a slight "simplification" of a somewhat more
complicated one.

The thing that messes up a lot of people is that you can have
three airplanes ready to take off on the same strip under the same
conditions and one of them (higher powered) is best off to go
uphill into the wind, one of them best off downhill with the wind,
and with the third it makes no difference (unless there are other
considerations like terrain clearance, etc.)

Hope this helps more than it confuses.
John T. Lowry

[[email protected]]

The pilot in command is responsible for the safety of the flight. If I
arrive at a non towered field and notice the pattern doesn't reflect
the current winds I observe who was there first and in what order, I
then make a radio call announcing my intentions of reversing the
pattern, I let those before me to do whatever please and when its my
turn I fly the pattern that is best for my safety. I dread the thought
of sitting at an FAA/NTSB inquiry and stating the " yeah they were
landing downwind so I did it too" excuse....... Kinda likesaying" all
the others jumped off the cliff so I did it too".. :<)..

Ben
N801BH
www.haaspowerair.com


On Sep 23, 5:26 am, "Oz Lander" > wrote:
> Kyle Boatright wrote:
> > And what is the correct radio phraseology to say: "Fellas, it is
> > time to reverse the pattern - you're taking off and landing
> > downwind.." ?
>
> This is the part I'm interested in hearing comments on.
>
> --
> Oz Lander.
> Straight and Level Forum.http://z7.invisionfree.com/Straight_and_Level/index.php?act=idx

[Robert M. Gary]

On Sep 22, 8:01 pm, "Kyle Boatright" > wrote:
> What is your threshold for landing (or departing) downwind? Will you land
> knowing you have a 5 knot tailwind? 10 knots? At what point will you
> "flip" the pattern to takeoff or land into the wind?
>
> Me? I'm a <5 knot kind of guy (but I fly a taildragger)...
>
> I landed at 3 different fields today where the established pattern resulted
> in a landing with a quartering 7 knot (or more) tailwind, with some mild
> gusts thrown in for good measure.

Part of instrument training is to ensure students can land correctly
with a stiff tailwind (given a proper length runway). Instrument
approaches don't always line up with the wind.

-Robert, CFII

[Jim Burns]

"Kyle Boatright" >
> What is your threshold for landing (or departing) downwind?

Runway length.
Jim

[Kyle Boatright]

"Jim Burns" > wrote in message
...
>
> "Kyle Boatright" >
>> What is your threshold for landing (or departing) downwind?
>
> Runway length.
> Jim

Controllability doesn't enter into equation? It does for me.

With a 10 knot headwind, I have lots of rudder authority at 10 or 20 knots
of groundspeed on roll-out. With a 10 knot tailwind, there is no rudder
authority at 10 knots of groundspeed.

There is always the consideration of an engine failure. On takeoff or
landing, I'd prefer to be pointed into the wind if the prop stops, rather
than having to land downwind or attempt a low altitude turn into the wind...

KB

[Matt Whiting]

Kyle Boatright wrote:
> "Jim Burns" > wrote in message
> ...
>> "Kyle Boatright" >
>>> What is your threshold for landing (or departing) downwind?
>> Runway length.
>> Jim
>
> Controllability doesn't enter into equation? It does for me.
>
> With a 10 knot headwind, I have lots of rudder authority at 10 or 20 knots
> of groundspeed on roll-out. With a 10 knot tailwind, there is no rudder
> authority at 10 knots of groundspeed.
>
> There is always the consideration of an engine failure. On takeoff or
> landing, I'd prefer to be pointed into the wind if the prop stops, rather
> than having to land downwind or attempt a low altitude turn into the wind...

It would depend on what aircraft type you fly. With Cessna's and
Piper's, there is no need for rudder authority below 30 knots or even
higher. I've never flown an airplane with a free castering nose wheel,
but I suspect rudder authority is more important there, however, it
still seems like the brakes would work fine for directional control at
10 knots.

Matt

[[email protected]]

On Sep 23, 5:06 pm, Matt Whiting > wrote:
> It would depend on what aircraft type you fly. With Cessna's and
> Piper's, there is no need for rudder authority below 30 knots or even
> higher. I've never flown an airplane with a free castering nose wheel,
> but I suspect rudder authority is more important there, however, it
> still seems like the brakes would work fine for directional control at
> 10 knots.
>
> Matt

I've done downwind takeoffs and have scared myself a few times.
Even five or ten knots leaves you with less control, and I might wish
I had that control. Taking off in a gusting tailwind might drop you in
the weeds off the end of the runway, too.

Dan

[[email protected]]

Depends heavily on the aircraft. I know for a fact that a lightly
loaded DC-10 will not be able to
land and stop at McCarran with a 10+knot tailwind. Been onboard when
it was tried and
remember going off the airport boundries at less than 30 AGL You get a
new perspective on
things when you see TV antennas go by above you and chimmneys just
below you!

Lockheed L-10A is virtually impossible to land safely with any
tailwind. It has so much tail
surface that it either slams the tail down or tries to put it on the
nose.

deHaviland Super Chipmunk with a Krier tail gets super squirrelly with
any kind of tailwind. Of
course the tail will come off the ground at about 15 knots forward
speed

[Bertie the Bunyip[_19_]]

wrote in news:1190595059.529602.74370
@n39g2000hsh.googlegroups.com:

> Depends heavily on the aircraft. I know for a fact that a lightly
> loaded DC-10 will not be able to
> land and stop at McCarran with a 10+knot tailwind. Been onboard when
> it was tried and
> remember going off the airport boundries at less than 30 AGL You get a
> new perspective on
> things when you see TV antennas go by above you and chimmneys just
> below you!
>
> Lockheed L-10A is virtually impossible to land safely with any
> tailwind. It has so much tail
> surface that it either slams the tail down or tries to put it on the
> nose.
>
> deHaviland Super Chipmunk with a Krier tail gets super squirrelly with
> any kind of tailwind. Of
> course the tail will come off the ground at about 15 knots forward
> speed
>
>



These are all completely incorrect.

You can get a DC-10 at max landing weight into a 6,000 foot strip
easily. Even hot and high.

I've routinely operated an A300 into a 6,000 fooot strip with a fifteen
knot tailwind limit (which we often were up against due to the natur of
the strip) fro take off and landing.

I've landed ( a real) kissing cousin f the Lockheed 10, the Twin Beech,
with more than a 10 knot tailwind. It's fine... So would the Lockheed
be.

The Chipmunk, the same. All tailwheel airplanes get more demanding with
a tailwind as the groundspeed sinks to a point at which the surfaces
aren't doing much, but if the airplane was straight up to that point and
there isn't a massive crosswind, then the tailwheel and brakes take care
of the rest.

And I've flown a real Chipmunk...

Bertie

[Brian[_1_]]

> The tricky part of downwind landings is the necessity to extend your
> traffic pattern's Downwind Leg (actually against the wind in the case
> of a downwind landing) WELL BEYOND (perhaps double or more) what you
> are accustomed to in a normal into-the-wind landing. If you fail to
> do this, you will overshoot.


You are getting close to one of the answers.

Yes with a downwind landing you much more likely to overshoot. Since
you may overshoot you are much more likely need to Go Around. On the
Go around two more things happen. One, your climb out will climb out
at a much lower angle which may make it difficult or impossible to
clear obstacles. 2nd you will be close to the ground with a higher
than normal ground speed. The illusion of speed when combined with
approaching obstacles will make you want to climb a slower than normal
airspeed setting you up for a perfect Stall/Spin scenerio.

In fact I know of several Stall spins that have occurred exactly this
way.

One of my favorite demostrations is to simulate a power failure on a
windy day (and no one else in the pattern) when the only runway option
is the downwind runway. Once the student shown me they have they have
the runway made or they overshoot, (as they often do) I request a go
around so they can see how poor the climb angle really is when
departing downwind. With a 15 to 20kt tailwind in a C-150 or Tomahawk
this climbout can be impressively low.

Brian
CFIIG/ASEL

[Larry Dighera]

On Sun, 23 Sep 2007 19:37:38 -0700, Brian > wrote
in om>:

>
>> The tricky part of downwind landings is the necessity to extend your
>> traffic pattern's Downwind Leg (actually against the wind in the case
>> of a downwind landing) WELL BEYOND (perhaps double or more) what you
>> are accustomed to in a normal into-the-wind landing. If you fail to
>> do this, you will overshoot.
>
>
>You are getting close to one of the answers.

The answer to which question?

>Yes with a downwind landing you [are] much more likely to overshoot.

Right. But I can't emphasize too much the necessity to extend the
"Downwind Leg" to WELL beyond the point where the runway threshold is
at a 45 degree angle to the aircraft's position on the Downwind Leg
(as would be normal for an into-the-wind landing approach), so that
there is enough time to descend on final approach without the wind
blowing the aircraft past the threshold while it is still too high to
touch down.

What do you teach as a rule-of-thumb to determine the point to turn
from Downwind Leg to Base Leg?

>Since
>you may overshoot you are much more likely need to Go Around. On the
>Go around two more things happen. One, your climb out will climb out
>at a much lower angle which may make it difficult or impossible to
>clear obstacles.

Right. While the approach descent-rate can be increased by employing
a forward slip to increase the angle, unfortunately, there is no
reciprocal method available to increase the climb angle.

>2nd you will be close to the ground with a higher
>than normal ground speed. The illusion of speed when combined with
>approaching obstacles will make you want to climb a[t] slower than normal
>airspeed[,] setting you up for a perfect Stall/Spin scenerio.

Good point.

Fortunately, I haven't experienced a downwind go-around into rising
terrain, but wouldn't the orographic lifting of the wind against the
terrain produce some updraft (or vertical component) to assist in
increasing the rate of climb? Or is that just wishful thinking?

>In fact I know of several Stall spins that have occurred exactly this
>way.

The illusion is so strong, it's easy to understand how that might
happen if the pilot fails to monitor the airspeed indicator to
maintain Vx speed on climb-out.

>One of my favorite demostrations is to simulate a power failure on a
>windy day (and no one else in the pattern) when the only runway option
>is the downwind runway. Once the student [has] shown me they have they have[sic]
>the runway made or they overshoot, (as they often do) I request a go
>around so they can see how poor the climb angle really is when
>departing downwind. With a 15 to 20kt tailwind in a C-150 or Tomahawk
>this climbout can be impressively low.
>
>Brian
>CFIIG/ASEL

I can see how that would be important.

[Jay Honeck]

> And I've flown a real Chipmunk...

Hope the ASPCA doesn't hear about this...

http://www.aspca.org

;-)
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Bertie the Bunyip[_19_]]

Jay Honeck > wrote in news:1190639592.333060.145150
@d55g2000hsg.googlegroups.com:

>> And I've flown a real Chipmunk...
>
> Hope the ASPCA doesn't hear about this...
>
> http://www.aspca.org
>

Groan!


I think we just heard from one of Anthony's simmer buddies...



Bertie

[John T]

"Kyle Boatright" > wrote in message

>
> There is always the consideration of an engine failure. On takeoff or
> landing, I'd prefer to be pointed into the wind if the prop stops,
> rather than having to land downwind or attempt a low altitude turn
> into the wind...

I'd rather be pointed into the wind, too, but if the failure happens away
from the field, I think I'd be a lot less concerned with landing into the
wind than I would in actually making the field.

--
John T
http://sage1solutions.com/blogs/TknoFlyer
http://sage1solutions.com/products
NEW! FlyteBalance v2.0 (W&B); FlyteLog v2.0 (Logbook)
____________________

[Montblack]

("Bertie the Bunyip" wrote)
>>> And I've flown a real Chipmunk...

>> Hope the ASPCA doesn't hear about this...
>>
>> http://www.aspca.org

> I think we just heard from one of Anthony's simmer buddies...


You decide.

http://www.alexisparkinn.com/flight_simulator.htm
The "Kiwi" @ The Alexis Park Inn & Suites

BTW - BTDT


Montblack :-)

[Bertie the Bunyip[_19_]]

"John T" > wrote in
m:

> "Kyle Boatright" > wrote in message
>
>>
>> There is always the consideration of an engine failure. On takeoff
>> or landing, I'd prefer to be pointed into the wind if the prop stops,
>> rather than having to land downwind or attempt a low altitude turn
>> into the wind...
>
> I'd rather be pointed into the wind, too, but if the failure happens
> away from the field, I think I'd be a lot less concerned with landing
> into the wind than I would in actually making the field.
>

True, but downwind off field landings can be nasty. If it all goes horribly
wrong on you you'll be travelling a lot faster with a lot less control than
you would have with an into wind landing in an inferior field. Also, your
glide path control will be much more difficult with a tailwind for two
reasons. One, the angle will be much more shallow giving you progress
judgement difficulties and of course your glide angle will deteriorate as
the wind gradient gives you less tailwind as you descend. But as well as
this you won't be used to making a glide approach this way and your chancs
for success will be reduced because of this.
Having said all that, if you've only got one place to land and downwind is
the only way you can do it, well..


Bertie

[Bertie the Bunyip[_19_]]

"Montblack" > wrote in
:

> ("Bertie the Bunyip" wrote)
>>>> And I've flown a real Chipmunk...
>
>>> Hope the ASPCA doesn't hear about this...
>>>
>>> http://www.aspca.org
>
>> I think we just heard from one of Anthony's simmer buddies...
>
>
> You decide.
>
> http://www.alexisparkinn.com/flight_simulator.htm
> The "Kiwi" @ The Alexis Park Inn & Suites
>
> BTW - BTDT
>
>
> Montblack :-)
>
>
>

OK. Amazing how he knows how all those airplanes fly for a fact, eh?

What kind of asshole spends more on sim toys than an airplane would
cost?

We have one of these guys at work. He has spent, to date, over 50 grand
on a 767 sim in his garage. He once compared it to my building an
airplane defying me to point out any real difference between the
projects.
While the sim is technically daunting, and impressive, BTW, at the end
of the day I will have an airplane and he will have a great big Amiga
surrounded by painted up plywoood.


Bertie

[Cubdriver]

On Sat, 22 Sep 2007 23:01:54 -0400, "Kyle Boatright"
> wrote:

>And what is the correct radio phraseology to say: "Fellas, it is time to
>reverse the pattern - you're taking off and landing downwind.." ?

I don't know if it's correct, but I can tell you the reply I got when
I tried it:

"Pilot's discretion."

(To make matters worse, it was right traffic on 33, left traffic on
15.)

Blue skies! -- Dan Ford

Claire Chennault and His American Volunteers, 1941-1942
new from HarperCollins www.FlyingTigersBook.com

[Dane Spearing]

In article >,
Matt Whiting > wrote:
>>>> What is your threshold for landing (or departing) downwind?
>>> Runway length.
>>> Jim
>>
>> Controllability doesn't enter into equation? It does for me.
>>
>> With a 10 knot headwind, I have lots of rudder authority at 10 or 20 knots
>> of groundspeed on roll-out. With a 10 knot tailwind, there is no rudder
>> authority at 10 knots of groundspeed.
>>
>> There is always the consideration of an engine failure. On takeoff or
>> landing, I'd prefer to be pointed into the wind if the prop stops, rather
>> than having to land downwind or attempt a low altitude turn into the wind...
>
>It would depend on what aircraft type you fly. With Cessna's and
>Piper's, there is no need for rudder authority below 30 knots or even
>higher. I've never flown an airplane with a free castering nose wheel,
>but I suspect rudder authority is more important there, however, it
>still seems like the brakes would work fine for directional control at
>10 knots.

My home airport (KLAM) is a one-way airport. All landings are on rw 27,
all departures are on rw 9 regardless of wind conditions. This is due to
rapidly rising terrain to the west, as well as the presence of nearby
restricted airspace and a townsite immediately to the west. Thus, I
have *lots* of experience in landing and taking off with a tailwind.
The most important thing I've learned is this: AIRSPEED AIRSPEED AIRSPEED!
Ignore how fast you *think* you're going. Ignore how fast the outside world
looks like it's going by. Pay attention to the airspeed.

Other posters are correct in that you need to turn base further out when
landing with a tailwind. How much farther out? Depends on the tailwind. :)
I wish there were an easy rule of thumb (like "turn base when the approach
end is 45 deg behind your wing), but there isn't.

In years of doing this, my own personal minimums (or perhaps "maximums" in
this case) are < 15 kt direct tailwind. This is at an airport that sits
at 7300' MSL and has a 5300' runway, and I fly a PA32-300. If it's warm out
(> 70 deg F), and the density altitude starts to creep up, that maximum will
go down.

I haven't found controlability to be much of an issue with tailwind t/o's
or landings, but then I fly a wide gear Cherokee 6. It can be with a
taildragger. The shallower climb angle is also most certainly something to
consider, especially if there are obstructions at the departure end of the
runway. Fortunately, at my home airport, the east end of the runway ends
in a serious downward cliff.

My recommendation: pay attention to the AIRSPEED! (and practice a few
tailwind landings and/or takeoffs - they're really not as terrifying
as they're made out to be).

-- Dane

[Matt Whiting]

Bertie the Bunyip wrote:
> "Montblack" > wrote in
> :
>
>> ("Bertie the Bunyip" wrote)
>>>>> And I've flown a real Chipmunk...
>>>> Hope the ASPCA doesn't hear about this...
>>>>
>>>> http://www.aspca.org
>>> I think we just heard from one of Anthony's simmer buddies...
>>
>> You decide.
>>
>> http://www.alexisparkinn.com/flight_simulator.htm
>> The "Kiwi" @ The Alexis Park Inn & Suites
>>
>> BTW - BTDT
>>
>>
>> Montblack :-)
>>
>>
>>
>
> OK. Amazing how he knows how all those airplanes fly for a fact, eh?
>
> What kind of asshole spends more on sim toys than an airplane would
> cost?
>
> We have one of these guys at work. He has spent, to date, over 50 grand
> on a 767 sim in his garage. He once compared it to my building an
> airplane defying me to point out any real difference between the
> projects.

This is too easy. A real airplane can physically transport you to
distant places. A simulator can not.

Matt

[Bertie the Bunyip[_19_]]

Matt Whiting > wrote in news:W6XJi.71$2n4.4565
@news1.epix.net:

> Bertie the Bunyip wrote:
>> "Montblack" > wrote in
>> :
>>
>>> ("Bertie the Bunyip" wrote)
>>>>>> And I've flown a real Chipmunk...
>>>>> Hope the ASPCA doesn't hear about this...
>>>>>
>>>>> http://www.aspca.org
>>>> I think we just heard from one of Anthony's simmer buddies...
>>>
>>> You decide.
>>>
>>> http://www.alexisparkinn.com/flight_simulator.htm
>>> The "Kiwi" @ The Alexis Park Inn & Suites
>>>
>>> BTW - BTDT
>>>
>>>
>>> Montblack :-)
>>>
>>>
>>>
>>
>> OK. Amazing how he knows how all those airplanes fly for a fact, eh?
>>
>> What kind of asshole spends more on sim toys than an airplane would
>> cost?
>>
>> We have one of these guys at work. He has spent, to date, over 50
grand
>> on a 767 sim in his garage. He once compared it to my building an
>> airplane defying me to point out any real difference between the
>> projects.
>
> This is too easy. A real airplane can physically transport you to
> distant places. A simulator can not.

The idiocy of the statement just left everyone in the crewroom
speechless. Interstingly, when this guy is relatively sharp in the
airplane, but when he makes a big mistake, he's absolutely
flabbergasted. so much so that he loses the plot. He's done it a couple
of times flying with me. Worse still, he has aspirations of becoming a
check airman! Problem is, he probably will and I can't think of anyone
less suitable. If he was fatter and never left the house he could be
Anthony!


Bertie