Variations in soft field landings

[Maxwell]

I was taught to lift the flaps immediately upon touch down on soft field
landings. My instructors stated getting more weight on the brakes as soon as
possible, would facilitate a quicker stop than leaving the flaps down for
drag, and loosing some braking power to the extra lift.

However, during my last BFR, the instructor corrected me very sharply. He
insisted you get more drag from the flaps by leaving them down until you
slowed to taxi speed, than the benefit of more weight on the brakes.

What is the general consensus of the group? Flaps up or down, after
touchdown on a soft field landing?

[Matt Whiting]

Maxwell wrote:
> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as soon as
> possible, would facilitate a quicker stop than leaving the flaps down for
> drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

You definitely should not raise the flaps on a soft field landing! Are
you sure you aren't thinking of a short field landing instead? Even
then, I wouldn't recommend it although I do know CFIs who do make this
recommendation. However, I've never heard such a recommendation for a
soft field. Trust me, braking isn't a problem on a truly soft field!


Matt

[Blueskies]

"Maxwell" > wrote in message m...
:I was taught to lift the flaps immediately upon touch down on soft field
: landings. My instructors stated getting more weight on the brakes as soon as
: possible, would facilitate a quicker stop than leaving the flaps down for
: drag, and loosing some braking power to the extra lift.
:
: However, during my last BFR, the instructor corrected me very sharply. He
: insisted you get more drag from the flaps by leaving them down until you
: slowed to taxi speed, than the benefit of more weight on the brakes.
:
: What is the general consensus of the group? Flaps up or down, after
: touchdown on a soft field landing?
:
:

Leave the flaps down for soft field so you don't dig in. Raise the flaps on asphalt or other good braking surface for
max braking performance on a short field while keeping the stick back...

[Erik]

Maxwell wrote:

> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as soon as
> possible, would facilitate a quicker stop than leaving the flaps down for
> drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?
>
>

Regardless of the type of landing, even short field or soft, I've
always been taught to clean up the aircraft after I'm clear of the
runway. I don't touch anything until then. So, keep them down, I've
been taught.

[Newps]

Erik wrote:

>
> Regardless of the type of landing, even short field or soft, I've
> always been taught to clean up the aircraft after I'm clear of the
> runway. I don't touch anything until then. So, keep them down, I've
> been taught.
>

That is the weekend pilot information you got there. You give up
performance but you'll never retract the wheels on the ground. It's a
newbie answer. Are you a newbie?

[Peter R.]

On 4/25/2007 6:11:13 PM, "Blueskies" wrote:

> Leave the flaps down for soft field so you don't dig in. Raise the flaps
> on asphalt or other good braking surface for max braking performance on a
> short field while keeping the stick back...

That's how I learned it and IIRC, that is how Cessna lays it out in the
procedure section of the POH for the newer model C172s (the relevance here
being that this was the aircraft in which I originally trained).

--
Peter

[Orval Fairbairn]

In article >,
"Maxwell" > wrote:

> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as soon as
> possible, would facilitate a quicker stop than leaving the flaps down for
> drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

On a "soft field landing," it is presumed that you have lots of runway,
but it is soft (muddy). Leave the flaps down, stick full back, so you
slow down more rapidly and settle at a lower airspeed. You can leave
some power in, with the stick full aft, to taxi to an intended turnoff.

I think that the original poster has "soft field" confused with "short
field," where you need to get on the brakes as soon as possible, so you
dump the flaps immediately.

[TheSmokingGnu]

Maxwell wrote:
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

Flaps down! Unless it's a short, soft field, in which case you should
reconsider using it at all.

I was taught to go flaps-up on a short field for that reason, to
increase braking power. However, you have to consider the speed of
retraction available: it's a lot easier to do quickly in say a
Johnson-barred example than it is with a fully electric set (or hydraulics).

Plus, you have to consider your dedication to the landing (ie, will this
bounce and need a go-round), as well as your cockpit load. Nothing is
worse than coming down, slapping what you think is the right lever,
hitting a bounce, and coming in gear up (which lever *did* you hit? :D).
It may be a better idea to sacrifice that tiny inkling of braking action
to ensure that you can make positive reinforcement of the controls.

TheSmokingGnu

[R. Gardner]

Not a newbie issue, years ago while flying at a USAF aero club. The club
manager with plenty of hours did that in a M20C. Damn near canceled my CA
to PA cross country for my 21st Birthday but they got it fixed just in time.

So it can happen Newbie or not.

Ron Gardner
"Newps" > wrote in message
. ..
>
>
> Erik wrote:
>
>>
>> Regardless of the type of landing, even short field or soft, I've
>> always been taught to clean up the aircraft after I'm clear of the
>> runway. I don't touch anything until then. So, keep them down, I've
>> been taught.
>>
>
> That is the weekend pilot information you got there. You give up
> performance but you'll never retract the wheels on the ground. It's a
> newbie answer. Are you a newbie?

[Erik]

Newps wrote:

>
>
> Erik wrote:
>
>>
>> Regardless of the type of landing, even short field or soft, I've
>> always been taught to clean up the aircraft after I'm clear of the
>> runway. I don't touch anything until then. So, keep them down, I've
>> been taught.
>>
>
> That is the weekend pilot information you got there. You give up
> performance but you'll never retract the wheels on the ground. It's a
> newbie answer. Are you a newbie?

Yep, I'm a n00b. And it's a pain in the ass trying to retract the
wheels on those damn 150's. It's a manual procedure that's fairly
difficult to extend as well.

I'm also not fortunate to be a weekend pilot. More like a monthly
pilot. $100 hamburgers are good, but can't do that weekly :(

[Peter Clark]

On Wed, 25 Apr 2007 22:10:06 GMT, Matt Whiting >
wrote:

>Maxwell wrote:
>> I was taught to lift the flaps immediately upon touch down on soft field
>> landings. My instructors stated getting more weight on the brakes as soon as
>> possible, would facilitate a quicker stop than leaving the flaps down for
>> drag, and loosing some braking power to the extra lift.
>>
>> However, during my last BFR, the instructor corrected me very sharply. He
>> insisted you get more drag from the flaps by leaving them down until you
>> slowed to taxi speed, than the benefit of more weight on the brakes.
>>
>> What is the general consensus of the group? Flaps up or down, after
>> touchdown on a soft field landing?
>
>You definitely should not raise the flaps on a soft field landing! Are
>you sure you aren't thinking of a short field landing instead? Even
>then, I wouldn't recommend it although I do know CFIs who do make this
>recommendation. However, I've never heard such a recommendation for a
>soft field. Trust me, braking isn't a problem on a truly soft field!

FWIW, 172S and 182T checklists both say flaps up after landing for
short field to get weight on wheels and better breaking.

I wouldn't pull the flaps on soft either, the last thing you want on a
soft field is extra weight to dig in the wheels and heavy breaking....

[Matt Whiting]

Erik wrote:
> Maxwell wrote:
>
>> I was taught to lift the flaps immediately upon touch down on soft
>> field landings. My instructors stated getting more weight on the
>> brakes as soon as possible, would facilitate a quicker stop than
>> leaving the flaps down for drag, and loosing some braking power to the
>> extra lift.
>>
>> However, during my last BFR, the instructor corrected me very sharply.
>> He insisted you get more drag from the flaps by leaving them down
>> until you slowed to taxi speed, than the benefit of more weight on the
>> brakes.
>>
>> What is the general consensus of the group? Flaps up or down, after
>> touchdown on a soft field landing?
>>
>
> Regardless of the type of landing, even short field or soft, I've
> always been taught to clean up the aircraft after I'm clear of the
> runway. I don't touch anything until then. So, keep them down, I've
> been taught.
>

Yes, that is how I was taught, but it appears that later model Cessna's
recommend differently.

Matt

[Sylvain]

Maxwell wrote:

> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

what does the POH say? if it says anything about it, that's what you
do; if the POH doesn't say anything, what does the FAA says, i.e.,
chapter 8.17 of the Airplane Flying Handbook (FAA-H-8083-3A)

In either case, politely remind the instructor that this is a *soft*
landing and not a *short* landing so effective braking is not an issue
(on a real soft field, slowing down will be taken care of by the field,
don't worry about it :-)

--Sylvain

[Maxwell]

"Maxwell" > wrote in message
m...
>I was taught to lift the flaps immediately upon touch down on soft field
>landings. My instructors stated getting more weight on the brakes as soon
>as possible, would facilitate a quicker stop than leaving the flaps down
>for drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?
>

Yes, my mistake guy. I did mean short field landing.

[Maxwell]

"Sylvain" > wrote in message
t...
> Maxwell wrote:
>
>> What is the general consensus of the group? Flaps up or down, after
>> touchdown on a soft field landing?
>
> what does the POH say? if it says anything about it, that's what you
> do; if the POH doesn't say anything, what does the FAA says, i.e.,
> chapter 8.17 of the Airplane Flying Handbook (FAA-H-8083-3A)
>

The POH is a little unclear. It does list "flaps up" as the last item on the
check list, but it doesn't clairify "upon" touch down.

[Newps]

Maxwell wrote:
> "Sylvain" > wrote in message

>
> The POH is a little unclear. It does list "flaps up" as the last item on the
> check list, but it doesn't clairify "upon" touch down.
>


The POH is not the place to go to attain max performance for something
like a soft or short field landing.

[Sylvain]

Newps wrote:

> The POH is not the place to go to attain max performance for something
> like a soft or short field landing.

I would still prefer what the POH says to any amount of advice heard during
hangar flying and/or read on internet. Moreover if an instructor says
something that contradicts the POH and/or the Airplane Flying Handbook,
that instructor would have to come up with a really good explanation if
s/he wants to see me as a customer again.

--Sylvain

[Newps]

Sylvain wrote:

> Newps wrote:
>
>
>>The POH is not the place to go to attain max performance for something
>>like a soft or short field landing.
>
>
> I would still prefer what the POH says to any amount of advice heard during
> hangar flying and/or read on internet. Moreover if an instructor says
> something that contradicts the POH and/or the Airplane Flying Handbook,
> that instructor would have to come up with a really good explanation if
> s/he wants to see me as a customer again.
>

You need an instructor that plays in the dirt alot. I'm not an
instructor but I will outperform any of your typical college flyboy
instructors for short field landings. That's what I'm good at, but
don't ask me to help you fly a turn around a point. The POH is general
info, you want to do it at a higher level of performance you find the
people who do it all the time. Some of them may even be instructors,
like the people in McCall, ID.

[Maxwell]

"Newps" > wrote in message
. ..
>
>
> Sylvain wrote:
>
>> Newps wrote:
>>
>>
>>>The POH is not the place to go to attain max performance for something
>>>like a soft or short field landing.
>>
>>
>> I would still prefer what the POH says to any amount of advice heard
>> during
>> hangar flying and/or read on internet. Moreover if an instructor says
>> something that contradicts the POH and/or the Airplane Flying Handbook,
>> that instructor would have to come up with a really good explanation if
>> s/he wants to see me as a customer again.
>>
>
> You need an instructor that plays in the dirt alot. I'm not an instructor
> but I will outperform any of your typical college flyboy instructors for
> short field landings. That's what I'm good at, but don't ask me to help
> you fly a turn around a point. The POH is general info, you want to do it
> at a higher level of performance you find the people who do it all the
> time. Some of them may even be instructors, like the people in McCall,
> ID.

Actually I agree with both of you, and no, that instructor with never see me
again for a number of reasons. I just don't know where it got his info and
thought maybe there was so new thinking on the subject. It's been 35 years
since I got my PPL, so I try to keep my eyes open.

[Jim Carter[_1_]]

back when we had 40 - 50 - or 60 degrees of flaps available we didn't always
raise them even for short field landings. At 60 degrees and full back
elevator the O-1 would almost hover to a landing, brakes were kind of
ornamental at times.

The point is it all depends on the aircraft you're flying, the surface
friction, and where you want to turn-off. There shouldn't be a pedantic
mantra that you follow regardless of circumstance.

--
Jim Carter
Rogers, Arkansas
"Matt Whiting" > wrote in message
...
> Maxwell wrote:
>> I was taught to lift the flaps immediately upon touch down on soft field
>> landings. My instructors stated getting more weight on the brakes as soon
>> as possible, would facilitate a quicker stop than leaving the flaps down
>> for drag, and loosing some braking power to the extra lift.
>>
>> However, during my last BFR, the instructor corrected me very sharply. He
>> insisted you get more drag from the flaps by leaving them down until you
>> slowed to taxi speed, than the benefit of more weight on the brakes.
>>
>> What is the general consensus of the group? Flaps up or down, after
>> touchdown on a soft field landing?
>
> You definitely should not raise the flaps on a soft field landing! Are
> you sure you aren't thinking of a short field landing instead? Even then,
> I wouldn't recommend it although I do know CFIs who do make this
> recommendation. However, I've never heard such a recommendation for a
> soft field. Trust me, braking isn't a problem on a truly soft field!
>
>
> Matt

[Jim Carter[_1_]]

Short, soft fields are really pretty easy to get into; they're a bitch to
get out of though

--
Jim Carter
Rogers, Arkansas

"TheSmokingGnu" > wrote in message
...
>
> Flaps down! Unless it's a short, soft field, in which case you should
> reconsider using it at all.
>
>
> TheSmokingGnu

[mike regish]

I was taught that way too, even though I assured all instructors that I
could barely afford to fly a fixed gear aircraft and was pretty sure I'd
never be flying a retract.

I've got Johnson bar flaps, so there's really not much chance of confusing
flaps with gear in my TP.

I'd keep flaps down for a soft field and flaps up and on the brakes for a
short field.

mike

"Newps" > wrote in message
. ..
>
>
> Erik wrote:
>
>>
>> Regardless of the type of landing, even short field or soft, I've
>> always been taught to clean up the aircraft after I'm clear of the
>> runway. I don't touch anything until then. So, keep them down, I've
>> been taught.
>>
>
> That is the weekend pilot information you got there. You give up
> performance but you'll never retract the wheels on the ground. It's a
> newbie answer. Are you a newbie?

[Matt Whiting]

Jim Carter wrote:
> Short, soft fields are really pretty easy to get into; they're a bitch to
> get out of though
>

Yes, you generally have to wait until the field is no longer soft ... or
truck out the airplane. :-)

Matt

[Robert M. Gary]

On Apr 25, 2:54 pm, "Maxwell" > wrote:
> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as soon as
> possible, would facilitate a quicker stop than leaving the flaps down for
> drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

I think you are mixing up short field and soft field. In an FAA soft
field (which oddly, is never short) you leave the flaps down and use
no brakes.

-robert, CFII

[Robert M. Gary]

On Apr 25, 5:20 pm, "Maxwell" > wrote:
> "Maxwell" > wrote in message
>
> m...
>
> >I was taught to lift the flaps immediately upon touch down on soft field
> >landings. My instructors stated getting more weight on the brakes as soon
> >as possible, would facilitate a quicker stop than leaving the flaps down
> >for drag, and loosing some braking power to the extra lift.
>
> > However, during my last BFR, the instructor corrected me very sharply. He
> > insisted you get more drag from the flaps by leaving them down until you
> > slowed to taxi speed, than the benefit of more weight on the brakes.
>
> > What is the general consensus of the group? Flaps up or down, after
> > touchdown on a soft field landing?
>
> Yes, my mistake guy. I did mean short field landing.

Well that makes more sense. Different POH's recommend flaps up or not
touch the flaps. Getting the flaps up will make the landing shorter
but has caused many pilots to accidently raise the gear, so many CFIs
say don't touch anything on roll out. Personally, I raise the flaps
because I take my Mooney to real soft fields in Mexico. However, for
those that use it as an academic exercise it may be more important to
make sure your student doesn't grab the gear switch (which is hard to
stop as a CFII).

-Robert, CFII

[B A R R Y[_2_]]

Maxwell wrote:
> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as soon as
> possible, would facilitate a quicker stop than leaving the flaps down for
> drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

First of all, have you checked your POH for clues?

Second, I think you have short and soft confused.

Soft fields slow the plane without brakes with surface drag. You don't
really want to STOP on a soft field, as you might even sink in. I was
taught to think ahead, so I didn't have to stop while taxiing on soft
conditions. I'd leave the flaps deployed while I concentrated on using
the elevator to keep the nose gear off the turf as much as possible,
which will also provide plenty of aero braking.

Short, paved fields are a different story. My Beech Sundowner has much
less braking ability with the flaps deployed, so I raise them as a
course of habit on pavement. The Piper PA-28 variations I've flown had
much better braking with the flaps out, raising the flaps didn't offer
anywhere near the braking improvement as with the Beech.

[JGalban via AviationKB.com]

Newps wrote:
>
>You need an instructor that plays in the dirt alot. I'm not an
>instructor but I will outperform any of your typical college flyboy
>instructors for short field landings. That's what I'm good at, but
>don't ask me to help you fly a turn around a point. The POH is general
>info, you want to do it at a higher level of performance you find the
>people who do it all the time. Some of them may even be instructors,
>like the people in McCall, ID.

Couldn't agree more. When doing pretend short field ops on a nice long
paved runway, the procedures in most POHs works just fine. When flying into
and out of an actual short strip, you're going to want to do everything you
can to maximize performance.

One example of this is the short field takeoff procedure I've seen in many
POHs that recommends standing on the brakes, going to full power, then
releasing the brakes. I never see anyone do this at short, high
backcountry strips (except for noobs). The rolling start is well known to
be superior.

As to the original question, there's a good reason for raising the flaps
just after touchdown (works best with manual flaps). Assuming that it's
really a short field, you can expect to be applying the brakes rather
vigorously, ASAP. If the wings are still carrying a lot of the aircraft
weight, it will be very easy to lock up the brakes inadvertently. If you
killed the lift by raising the flaps, you'll have much more effective braking.
You'll also be less likely to inadvertently flat-spot, or put a hole in your
tire. Something I've seen happen more than a few times on planes practicing
short field landings.

John Galban=====>N4BQ (PA28-180)

--
Message posted via AviationKB.com
http://www.aviationkb.com/Uwe/Forums.aspx/aviation/200704/1

[Bob Gardner]

It's the old "my instructor said..." story instead of reading the book. The
Airplane Flying Handbook says, on page 8-20, "If flaps are used, it is
generally inadvisable to retract them during the after-landing roll because
the need for flap retraction is usually less important than the need for
total concentration on maintaining full control of the airplane."

Gotta wonder (1) why the flaps-up instructor doesn't go by the book, and (2)
why you swallow his story without asking for documentation for his method.

Bob Gardner


"Maxwell" > wrote in message
m...
>I was taught to lift the flaps immediately upon touch down on soft field
>landings. My instructors stated getting more weight on the brakes as soon
>as possible, would facilitate a quicker stop than leaving the flaps down
>for drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?
>

[bobmrg]

On Apr 25, 2:54 pm, "Maxwell" > wrote:
> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as soon as
> possible, would facilitate a quicker stop than leaving the flaps down for
> drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply. He
> insisted you get more drag from the flaps by leaving them down until you
> slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

Please ignore my comments about soft-field landings (although I still
think you should use your reference material when your instructor says
something questionable instead of accepting it as gospel). The
Airplane Flying Handbook is silent on retracting flaps after touching
down on short field...go by the POH recommendation.

Instructors are often wrong...I know because I are one.

Bob Gardner

[Newps]

JGalban via AviationKB.com wrote:

>
> One example of this is the short field takeoff procedure I've seen in many
> POHs that recommends standing on the brakes, going to full power, then
> releasing the brakes. I never see anyone do this at short, high
> backcountry strips (except for noobs). The rolling start is well known to
> be superior.
>

Yep, even a 20 foot perpindicular start to the actual runway helps.
Ain't no way I'm going to sit at the approach end of any runway and
runup to full power with the brakes on in my plane. If you want that
we'll do it in your plane.



> As to the original question, there's a good reason for raising the flaps
> just after touchdown (works best with manual flaps). Assuming that it's
> really a short field, you can expect to be applying the brakes rather
> vigorously, ASAP.


I've found best performance to be a carrier type landing. Fly it into
the ground at minimum speed, as soon as you hit lock the brakes, stick
full back and hit the flap switch. Let up slightly on the brakes every
now and again, I've found just a little slippage is better than totally
locked. Non pavement only, of course.

[Capt. Geoffrey Thorpe]

"Jim Carter" > wrote in message
et...
> back when we had 40 - 50 - or 60 degrees of flaps available we didn't
> always raise them even for short field landings. At 60 degrees and full
> back elevator the O-1 would almost hover to a landing, brakes were kind of
> ornamental at times.
>
> The point is it all depends on the aircraft you're flying, the surface
> friction, and where you want to turn-off. There shouldn't be a pedantic
> mantra that you follow regardless of circumstance.
>
> --
> Jim Carter
> Rogers, Arkansas

B I N G O !

Plus what works in airplane A is likely to be very costly in airplane B...

Examples. In a Cessna 120, the best short field technique I've found is to
simply plant the mains as soon as you get down to the ground (and over the
threshold) and lean on the brakes. If you try to 3-point, all you are going
to do is float if you are even a teeny bit fast. In a Luscombe, as I
understand it, that technique will get you stopped quickly but cost you a
prop and engine overhaul. Try it in a Cessna 150 and you are going to
wheelborrow and stand a chance of doing some significant damage.

If you have a Johnsen bar for the flaps and fixed gear, it MIGHT make sense
to retract. If you have electric flaps that take 15 - 20 seconds to retract,
and the flap lever is right next to the gear - well - I could probably think
of dumber things to do, but I'd have to work at it.

Learn to fly whatever airplane you are flying. They all have their
differences. That's why there is more than one kind.

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

[Blueskies]

"Robert M. Gary" > wrote in message oups.com...
: On Apr 25, 5:20 pm, "Maxwell" > wrote:
: > "Maxwell" > wrote in message
: >
: > m...
: >
: > >I was taught to lift the flaps immediately upon touch down on soft field
: > >landings. My instructors stated getting more weight on the brakes as soon
: > >as possible, would facilitate a quicker stop than leaving the flaps down
: > >for drag, and loosing some braking power to the extra lift.
: >
: > > However, during my last BFR, the instructor corrected me very sharply. He
: > > insisted you get more drag from the flaps by leaving them down until you
: > > slowed to taxi speed, than the benefit of more weight on the brakes.
: >
: > > What is the general consensus of the group? Flaps up or down, after
: > > touchdown on a soft field landing?
: >
: > Yes, my mistake guy. I did mean short field landing.
:
: Well that makes more sense. Different POH's recommend flaps up or not
: touch the flaps. Getting the flaps up will make the landing shorter
: but has caused many pilots to accidently raise the gear, so many CFIs
: say don't touch anything on roll out. Personally, I raise the flaps
: because I take my Mooney to real soft fields in Mexico. However, for
: those that use it as an academic exercise it may be more important to
: make sure your student doesn't grab the gear switch (which is hard to
: stop as a CFII).
:
: -Robert, CFII
:


Raising the gear will definitely shorten the landing roll.... ;-)

[Sylvain]

Blueskies wrote:
>
> Raising the gear will definitely shorten the landing roll.... ;-)

Technically though, when on the ground, you are not raising the gear; the
gear stays just where it is, more or less, on the ground. You are however
lowering the fuselage.

:-)

--Sylvain

[TheSmokingGnu]

Sylvain wrote:
> You are however
> lowering the fuselage.

Has a nasty habit of raising your premiums in the process. :D

Thus, I submit Gnu's Law, that insurance cost is inversely proportional
to height above ground.

TheSmokingGnu

[Roger (K8RI)]

On Wed, 25 Apr 2007 16:54:23 -0500, "Maxwell" >
wrote:

>I was taught to lift the flaps immediately upon touch down on soft field
>landings. My instructors stated getting more weight on the brakes as soon as
>possible, would facilitate a quicker stop than leaving the flaps down for
>drag, and loosing some braking power to the extra lift.
>
>However, during my last BFR, the instructor corrected me very sharply. He
>insisted you get more drag from the flaps by leaving them down until you
>slowed to taxi speed, than the benefit of more weight on the brakes.
>
>What is the general consensus of the group? Flaps up or down, after
>touchdown on a soft field landing?
>

Hopefully here won't be a consensus. It depends on the airplane,
pilot, and technique.

The short field landing which you are describing, rather than soft
field usually has a recommendation in the POH which may, or not give
the shortest landing possible including roll out. However that
landing was done using the best possible application of normal
techniques with a very good pilot who knew the specific make and model
far better than the average pilot.

One thing short field landings have in common is a STEEP final where
energy/speed is bled off in the round out. In some planes this means
carrying considerable power on the final just prior to the round out.
Dragging it in with the ability to set it down and stop on a postage
stamp is not a normal short field unless you are a bush pilot landing
on sand bars, or dragging it in over your neighbor's bean field. Even
then a good portion of the final (in ground effect) should be
considered as part of the landing.

There is one thing in normal short field landing I've heard with which
I disagree and that is holding the yoke back all the time. I plant
the mains on, immediately let the nose gear down, get on the brakes,
and THEN bring the yoke back again.

Something to remember in planes with electric flaps is the time it
takes to retract them and how much added lift you get during the
retraction. With most planes most of us are flying the last portion
of flap extension adds drag without adding lift. So when removing
flaps we remove drag, then add lift for a time before the flaps have
retraced enough to reduce the lift. I've found some planes where the
POH recommends raising the flaps can be almost brought to a stop
before the flaps are all the way up. That means in the latter portion
of the ground roll it didn't matter if the flaps were up or down. In
some of those cases raising the flaps adds lift right when you want to
get rid of it and removes drag right when it will do the most good.

One plane or rather group of planes where the retraction of the flaps
can be quite effective in shortening the rollout is the Cherokee
family that has the Johnson bar flaps (Mechanical). Actually it's the
only plane I've flown where the difference is quite noticeable.

"I believe" which is a personal opinion based only on my experience in
the specific 150s, 172s, Cherokees, Debonairs, and Bonanzas I've
flown, that it is possible to make the shortest landing possible by
leaving the flaps at full and a lot of practice. OTOH With the 150s
and 172s I doubt if most pilots are going to be able to see much if
any difference whether the flaps are raised or left down.

[Newps]

Roger (K8RI) wrote:

>
> There is one thing in normal short field landing I've heard with which
> I disagree and that is holding the yoke back all the time. I plant
> the mains on, immediately let the nose gear down, get on the brakes,
> and THEN bring the yoke back again.


Then you're too fast to start with. A short field landing is a
bang-bang play. Bang, the mains hit, then bang the nose wheel hits.
Stick position is irrelevant and won't really affect what happens with
the nosewheel because if you have your speed right any additional drag,
such as the mains hitting, means she's all done flying. The nose is
coming down and nothing short of a lot of power is going to change that.




>
> Something to remember in planes with electric flaps is the time it
> takes to retract them and how much added lift you get during the
> retraction. With most planes most of us are flying the last portion
> of flap extension adds drag without adding lift. So when removing
> flaps we remove drag, then add lift for a time before the flaps have
> retraced enough to reduce the lift.




Not correct. From full flaps, retracting any amount of flaps will
always reduce the total amount of lift the flaps are providing. On your
typical Cessna the majority of the lift comes in the first 20 degrees
with not a lot of added drag. But going from 20 to 40 degrees does add
lift, that's why the stall speed is lower at 40 flaps than at 20. So
reducing any flaps reduces lift, it raises the stall speed thereby
putting more weight on the wheels.

[Orval Fairbairn]

In article >,
"Blueskies" > wrote:

> "Robert M. Gary" > wrote in message

>
>
> Raising the gear will definitely shorten the landing roll.... ;-)

Trouble -- it will then take full power to taxi. ;>)

[Matt Whiting]

Newps wrote:

> I've found best performance to be a carrier type landing. Fly it into
> the ground at minimum speed, as soon as you hit lock the brakes, stick
> full back and hit the flap switch. Let up slightly on the brakes every
> now and again, I've found just a little slippage is better than totally
> locked. Non pavement only, of course.

Depends on the surface. If it is snow or sand, locking the wheels and
keeping them locked is best. If it is a harder surface that you can't
"plow" up, then incipient lock-up is best. Just like ABS on cars. It
works well on dry and wet pavement, but doesn't perform nearly as well
on snow or sand as compared to non-ABS brakes that can be locked.

Matt

[Morgans[_2_]]

> Thus, I submit Gnu's Law, that insurance cost is inversely proportional to
> height above ground.

Ooops. You mean directly proportional to the height above the ground.
--
Jim in NC

[Maxwell]

"Bob Gardner" > wrote in message
. ..
> It's the old "my instructor said..." story instead of reading the book.
> The Airplane Flying Handbook says, on page 8-20, "If flaps are used, it is
> generally inadvisable to retract them during the after-landing roll
> because the need for flap retraction is usually less important than the
> need for total concentration on maintaining full control of the airplane."
>
> Gotta wonder (1) why the flaps-up instructor doesn't go by the book, and
> (2) why you swallow his story without asking for documentation for his
> method.
>

Gotta wonder what page Bob, my copy doesn't specify under short field
landings. And a lot of inquiring minds here seem to disagree.

[Judah]

"Maxwell" > wrote in
m:

> I was taught to lift the flaps immediately upon touch down on soft field
> landings. My instructors stated getting more weight on the brakes as
> soon as possible, would facilitate a quicker stop than leaving the flaps
> down for drag, and loosing some braking power to the extra lift.
>
> However, during my last BFR, the instructor corrected me very sharply.
> He insisted you get more drag from the flaps by leaving them down until
> you slowed to taxi speed, than the benefit of more weight on the brakes.
>
> What is the general consensus of the group? Flaps up or down, after
> touchdown on a soft field landing?

I think it depends more on how fast you land...

If you land right at stall speed, retracting the flaps might help you break.
If you are faster, retracting the flaps will probably extend your rollout.

There are also a lot of people who say you shouldn't be under there during
that part of the landing phase in case some day you are flying a retract and
grab the wrong lever. Of course then those people go on to do go arounds and
touch and goes and do it anyway. ;)

[Judah]

Orval Fairbairn > wrote in
:

> On a "soft field landing," it is presumed that you have lots of runway,
> but it is soft (muddy). Leave the flaps down, stick full back, so you
> slow down more rapidly and settle at a lower airspeed. You can leave
> some power in, with the stick full aft, to taxi to an intended turnoff.

I don't think that presumption is accurate.

I wonder how many turf runways are not also < 2000'?

And I wonder how many < 2000' are not also turf...

[TheSmokingGnu]

Morgans wrote:
> Ooops. You mean directly proportional to the height above the ground.

No no, inverse. At zero height costs approach infinity, and at infinite
height, costs approach zero. <G>

Of course, Gnu's Law is only defined on [0, oo], I'm not sure what costs
do at negative heights. Perhaps a flight to Death Valley is warranted!

TheSmokingGnu