Does the elevator/stabilator generate upward force?

[Dan[_1_]]

Ok, this is a followup to the previous discussion about forward control
pressure during the landing rollout. Can someone tell me if the
elevator/stabilator can actually generate an _upward_ force, or does it
simply generate a downward force for climbing and less downward force
for a decent?

Does the nose fall due to the CG being forward of the center of lift,
or does the elevator actually push the tail up?

We are talking about tricycle gear planes, not taildraggers... The PA28
series specifically.

--Dan

[BT]

You tell me...

Next time you are doing your run up.. hold the brakes and move the control
foward and aft.. is the nose rising and falling because of action of wind
(prop wash) over the elevator position? Granted in a heavy PA28, it may not
be very noticable, but try it in a Cessna 152/172.

you are mixing apples in oranges when talking about "the nose falling due to
CG and center of lift".
IIRC the original thread was concerned with pushing the nose down to put
more weight on the nose wheel for cross wind control,
in the example you mention, it involves the nose falling forward because the
elevator/wings combination cannot generate enough "lift" in their respective
direction to keep the nose up.

Now.. lets expand on that a bit.. when performing an outside loop maneuver,
is the nose being pushed around the loop because the elevator is creating
less "lift" or because the elevator is forcing the nose around.

Why would a tricycle gear airplane behave any differently than a tail wheel
as far as elevator effectiveness. Other than possible physical limits
allowed to elevator travel.

In the only Piper POH I have avalible to be right now, On landing... ""After
ground contract hold the nose wheel off as long as possible. Braking is most
effective when back pressure is applied to the control wheel. In high wind
conditions, particularly in strong crosswinds, it may be desirable to
approach the ground at highter than normal speeds with partial or no flaps."

Funny, it says nothing about pushing forward on the stick for directional
control.

B

"Dan" > wrote in message
ups.com...
> Ok, this is a followup to the previous discussion about forward control
> pressure during the landing rollout. Can someone tell me if the
> elevator/stabilator can actually generate an _upward_ force, or does it
> simply generate a downward force for climbing and less downward force
> for a decent?
>
> Does the nose fall due to the CG being forward of the center of lift,
> or does the elevator actually push the tail up?
>
> We are talking about tricycle gear planes, not taildraggers... The PA28
> series specifically.
>
> --Dan
>

[Jim Macklin]

The tail can produce forces in either direction, although in
flight forces are mostly in the down direction at the tail.

The wing lift is concentrated aft of the CG so that there is
a nose down moment when the airplane becomes stalled. This
is for static stability. The initial movement for
statically stable airplanes must be toward a unstalled angle
of attack and flying speed. This happens with the tail
moment leveraging the turning moments to a balanced dynamic
position, which will decrease at lower speeds, causing the
static pitching moment downward.

But it can produce an upward force if the airplane is aft of
the CG range, in order to balance the airplane in flight.
But if you stall, the nose will pitch up into a deeper
stalled condition.
On landing the airplane will rotate [pitch] around the main
wheel axles and even the nose wheel which is wheel
barrowing.

The magnitude all depends on the center of gravity in
relation to the CG range and the amount of travel exerted.
Normal flight is very small movements and acrobatics, and
control forces below stall speed on the ground use control
displacements for gross changes.

The issue is not tail draggers, but tail or canard, the
location of the wheels in relation to the CG [wing chord]
only has to do with finer details, like rolling.



"Dan" > wrote in message
ups.com...
| Ok, this is a followup to the previous discussion about
forward control
| pressure during the landing rollout. Can someone tell me
if the
| elevator/stabilator can actually generate an _upward_
force, or does it
| simply generate a downward force for climbing and less
downward force
| for a decent?
|
| Does the nose fall due to the CG being forward of the
center of lift,
| or does the elevator actually push the tail up?
|
| We are talking about tricycle gear planes, not
taildraggers... The PA28
| series specifically.
|
| --Dan
|

[Jim Macklin]

Think loop: outside or inside.



"Dan" > wrote in message
ups.com...
| Ok, this is a followup to the previous discussion about
forward control
| pressure during the landing rollout. Can someone tell me
if the
| elevator/stabilator can actually generate an _upward_
force, or does it
| simply generate a downward force for climbing and less
downward force
| for a decent?
|
| Does the nose fall due to the CG being forward of the
center of lift,
| or does the elevator actually push the tail up?
|
| We are talking about tricycle gear planes, not
taildraggers... The PA28
| series specifically.
|
| --Dan
|

[Jim Macklin]

"you are mixing apples in oranges when talking about "the
nose falling due to
| CG and center of lift".
| IIRC the original thread was concerned with pushing the
nose down to put
| more weight on the nose wheel for cross wind control,"

Increased weight on the nose wheel makes the nose wheel the
pivot point and is guaranteed to cause loss of direct
WHEELBARROWING

Page 8-32
http://www.faa.gov/library/manuals/aircraft/airplane_handbook/
chap 7-9
When a pilot permits the airplane weight to become

concentrated about the nosewheel during the takeoff or

landing roll, a condition known as wheelbarrowing will

occur. Wheelbarrowing may cause loss of directional

control during the landing roll because braking action is

ineffective, and the airplane tends to swerve or pivot on

the nosewheel, particularly in crosswind conditions.

One of the most common causes of wheelbarrowing

during the landing roll is a simultaneous touchdown

of the main and nosewheel, with excessive speed,

followed by application of forward pressure on the

elevator control. Usually, the situation can be corrected

by smoothly applying back-elevator pressure.

However, if wheelbarrowing is encountered and

runway and other conditions permit, it may be advisable

to promptly initiate a go-around. Wheelbarrowing will

not occur if the pilot achieves and maintains the correct

landing attitude, touches down at the proper speed, and

gently lowers the nosewheel while losing speed on

rollout. If the pilot decides to stay on the ground rather

than attempt a go-around or if directional control is

lost, the throttle should be closed and the pitch attitude

smoothly but firmly rotated to the proper landing

attitude. Raise the flaps to reduce lift and to increase

the load on the main wheels for better braking action.






"BT" > wrote in message
...
| You tell me...
|
| Next time you are doing your run up.. hold the brakes and
move the control
| foward and aft.. is the nose rising and falling because of
action of wind
| (prop wash) over the elevator position? Granted in a heavy
PA28, it may not
| be very noticable, but try it in a Cessna 152/172.
|
| you are mixing apples in oranges when talking about "the
nose falling due to
| CG and center of lift".
| IIRC the original thread was concerned with pushing the
nose down to put
| more weight on the nose wheel for cross wind control,
| in the example you mention, it involves the nose falling
forward because the
| elevator/wings combination cannot generate enough "lift"
in their respective
| direction to keep the nose up.
|
| Now.. lets expand on that a bit.. when performing an
outside loop maneuver,
| is the nose being pushed around the loop because the
elevator is creating
| less "lift" or because the elevator is forcing the nose
around.
|
| Why would a tricycle gear airplane behave any differently
than a tail wheel
| as far as elevator effectiveness. Other than possible
physical limits
| allowed to elevator travel.
|
| In the only Piper POH I have avalible to be right now, On
landing... ""After
| ground contract hold the nose wheel off as long as
possible. Braking is most
| effective when back pressure is applied to the control
wheel. In high wind
| conditions, particularly in strong crosswinds, it may be
desirable to
| approach the ground at highter than normal speeds with
partial or no flaps."
|
| Funny, it says nothing about pushing forward on the stick
for directional
| control.
|
| B
|
| "Dan" > wrote in message
|
ups.com...
| > Ok, this is a followup to the previous discussion about
forward control
| > pressure during the landing rollout. Can someone tell
me if the
| > elevator/stabilator can actually generate an _upward_
force, or does it
| > simply generate a downward force for climbing and less
downward force
| > for a decent?
| >
| > Does the nose fall due to the CG being forward of the
center of lift,
| > or does the elevator actually push the tail up?
| >
| > We are talking about tricycle gear planes, not
taildraggers... The PA28
| > series specifically.
| >
| > --Dan
| >
|
|

[Peter Duniho]

"Dan" > wrote in message
ups.com...
> [...]
> We are talking about tricycle gear planes, not taildraggers... The PA28
> series specifically.

Where the landing gear is mounted has nothing to do with the forces that the
elevator creates. Several designs are basically identical, except for the
position of the landing gear (Pacer and Tri-Pacer, for example).

And yes, the elevator can create an upward force.

[[email protected]]

I'm kind of alarmed to hear that an instructor didn't explain to you
that the elevator generates lift.

[Peter Duniho]

> wrote in message
ps.com...
> I'm kind of alarmed to hear that an instructor didn't explain to you
> that the elevator generates lift.

To whom are you replying? If me, I have no idea what you're talking about.
Your reply has nothing to do with what I wrote.

If you're not replying to me, then I suggest you learn how to reply to the
message to which you intend to reply, or at a minimum learn how to *quote*
the text to which you're replying, so that people can tell what the heck
you're talking about.

Pete

[[email protected]]

Peter Duniho wrote:
> > wrote in message
> ps.com...
> > I'm kind of alarmed to hear that an instructor didn't explain to you
> > that the elevator generates lift.
>
> To whom are you replying? If me, I have no idea what you're talking about.
> Your reply has nothing to do with what I wrote.
>
> If you're not replying to me, then I suggest you learn how to reply to the
> message to which you intend to reply, or at a minimum learn how to *quote*
> the text to which you're replying, so that people can tell what the heck
> you're talking about.
>
> Pete

Not you... Dan.

[[email protected]]

wrote:
> Peter Duniho wrote:
> > > wrote in message
> > ps.com...
> > > I'm kind of alarmed to hear that an instructor didn't explain to you
> > > that the elevator generates lift.
> >
> > To whom are you replying? If me, I have no idea what you're talking about.
> > Your reply has nothing to do with what I wrote.
> >
> > If you're not replying to me, then I suggest you learn how to reply to the
> > message to which you intend to reply, or at a minimum learn how to *quote*
> > the text to which you're replying, so that people can tell what the heck
> > you're talking about.
> >
> > Pete
>
> Not you... Dan.

Plus I'm pretty sure my statement was pretty odvious in it's direction
to the original author... just like you said... your post had nothing
to do with it. Sorry if I've caused irrperable offense.

[Bob Noel]

In article m>,
" > wrote:

> Plus I'm pretty sure my statement was pretty odvious in it's direction
> to the original author

fwiw - no, your intended direction was not all obvious.

--
Bob Noel
Looking for a sig the
lawyers will hate

[Allen[_1_]]

"Dan" > wrote in message
ups.com...
> Ok, this is a followup to the previous discussion about forward control
> pressure during the landing rollout. Can someone tell me if the
> elevator/stabilator can actually generate an _upward_ force, or does it
> simply generate a downward force for climbing and less downward force
> for a decent?
>
> Does the nose fall due to the CG being forward of the center of lift,
> or does the elevator actually push the tail up?
>
> We are talking about tricycle gear planes, not taildraggers... The PA28
> series specifically.
>
> --Dan

I once saw a pair of mechanics doing a full power run-up in a Maule. They
were holding brakes on and forward elevator, the tail was about six feet in
the air standing still. So yes. Why do you separate the nosewheel from
the tailwheel? They both fly with the same principles.

Allen

[[email protected]]

Allen wrote:

> I once saw a pair of mechanics doing a full power run-up in a Maule. They
> were holding brakes on and forward elevator, the tail was about six feet in
> the air standing still. So yes. Why do you separate the nosewheel from
> the tailwheel? They both fly with the same principles.
>
> Allen

Aha, but you have to allow for the thrust line being so far
above the drag line, which in this case is the ground where the wheels
are locked. That thrust produces a pitching couple that raises the tail
much more effectively than the down-elevator. If the pilot holds full
forward elevator at the start of the takeoff roll, the tails of most
taildraggers won't come up until some considerable forward speed is
attained, and then the tail is rising mostly because the centre of
pressure of the wing, being behind the mains, is lifting it. Using
forward elevator will lift the tail sooner but it sure is not entirely
responsible for the rise.
Wheelbarrowing is also mostly caused by too-fast landing
speeds, not just forward elevator. It's worse with flaps down because
the wing's CP is ahead of the mains and is raising the tail.
Down-elevator isn't even necessary at high-enough speeds. The
nosewheels of most trikes is closer to the ground than the mains in
level flight attitude, and will contact first with the high airspeed
reducing AOA.

Dan (Instructor in taildraggers and trikes and a mechanic too)

[Dan[_1_]]

Yes, the elevetor generates lift, negative lift, 99.9% of the time, in
stable flight. If you look at most diagrams of aircraft forces, you
will see the CG with a force vector down, then behind that the center
of lift with a force vector upwards. Finally, the elevator is usually
drawn with a force vector downwards as well.

I would say there is a distinction between tailwheels and tricycle gear
aircraft. On a tailwheel, the CG is behind the main gear, on a
tricycle gear plane the CG is in front of the main gear.

Thanks for the example of the outside loop, I understand now. While
observing the range of stabilator deflection on a PA28, it seems to be
able to generate a _heck_ of a lot more downward force than upward
force, but apparently upward force is possible as well.


--Dan




wrote:
> I'm kind of alarmed to hear that an instructor didn't explain to you
> that the elevator generates lift.

[Capt. Geoffrey Thorpe]

"Dan" > wrote in message
ups.com...
> Ok, this is a followup to the previous discussion about forward control
> pressure during the landing rollout. Can someone tell me if the
> elevator/stabilator can actually generate an _upward_ force, or does it
> simply generate a downward force for climbing and less downward force
> for a decent?
>
> Does the nose fall due to the CG being forward of the center of lift,
> or does the elevator actually push the tail up?
>
> We are talking about tricycle gear planes, not taildraggers... The PA28
> series specifically.
>
> --Dan
>

Take the seat belt off the yoke of your PA28 and measure the angle between :
horizontal and the airfoil chord ( a line from the leading edge of the
stabalizer and the trailing edge of the elevator). You can use a yardstick
and protractor to get close enough. This will approximate the angle of
attack of the tail feathers with the aircraft in a level flight when full
forward stick is applied - right?. I suspect that it will be, what, 10 - 15
degrees? So, if the tail foil has a significant positive angle of attack,
how could it not be generating postitive lift?

--
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.

[Allen[_1_]]

> wrote in message
ups.com...
>
> Allen wrote:
>
>> I once saw a pair of mechanics doing a full power run-up in a Maule.
>> They
>> were holding brakes on and forward elevator, the tail was about six feet
>> in
>> the air standing still. So yes. Why do you separate the nosewheel from
>> the tailwheel? They both fly with the same principles.
>>
>> Allen
>
> Aha, but you have to allow for the thrust line being so far
> above the drag line, which in this case is the ground where the wheels
> are locked. That thrust produces a pitching couple that raises the tail
> much more effectively than the down-elevator. If the pilot holds full
> forward elevator at the start of the takeoff roll, the tails of most
> taildraggers won't come up until some considerable forward speed is
> attained, and then the tail is rising mostly because the centre of
> pressure of the wing, being behind the mains, is lifting it. Using
> forward elevator will lift the tail sooner but it sure is not entirely
> responsible for the rise.
> Wheelbarrowing is also mostly caused by too-fast landing
> speeds, not just forward elevator. It's worse with flaps down because
> the wing's CP is ahead of the mains and is raising the tail.
> Down-elevator isn't even necessary at high-enough speeds. The
> nosewheels of most trikes is closer to the ground than the mains in
> level flight attitude, and will contact first with the high airspeed
> reducing AOA.
>
> Dan (Instructor in taildraggers and trikes and a mechanic too)

I have seen a Super Cub land with a 40 knot (or so) headwind and come to a
complete stop, then raise the tail off the ground with the engine at idle.
I see you point about the thrust affecting pitch though, used that all the
time landing the Lear, as you bring the power levers to idle the nose
pitches up and automatically puts you into the flare.
Allen

[[email protected]]

Allen wrote:
> > wrote in message
> ups.com...
> >
> > Allen wrote:
> >
> >> I once saw a pair of mechanics doing a full power run-up in a Maule.
> >> They
> >> were holding brakes on and forward elevator, the tail was about six feet
> >> in
> >> the air standing still. So yes. Why do you separate the nosewheel from
> >> the tailwheel? They both fly with the same principles.
> >>
> >> Allen
> >
> > Aha, but you have to allow for the thrust line being so far
> > above the drag line, which in this case is the ground where the wheels
> > are locked. That thrust produces a pitching couple that raises the tail
> > much more effectively than the down-elevator. If the pilot holds full
> > forward elevator at the start of the takeoff roll, the tails of most
> > taildraggers won't come up until some considerable forward speed is
> > attained, and then the tail is rising mostly because the centre of
> > pressure of the wing, being behind the mains, is lifting it. Using
> > forward elevator will lift the tail sooner but it sure is not entirely
> > responsible for the rise.
> > Wheelbarrowing is also mostly caused by too-fast landing
> > speeds, not just forward elevator. It's worse with flaps down because
> > the wing's CP is ahead of the mains and is raising the tail.
> > Down-elevator isn't even necessary at high-enough speeds. The
> > nosewheels of most trikes is closer to the ground than the mains in
> > level flight attitude, and will contact first with the high airspeed
> > reducing AOA.
> >
> > Dan (Instructor in taildraggers and trikes and a mechanic too)
>
> I have seen a Super Cub land with a 40 knot (or so) headwind and come to a
> complete stop, then raise the tail off the ground with the engine at idle.
> I see you point about the thrust affecting pitch though, used that all the
> time landing the Lear, as you bring the power levers to idle the nose
> pitches up and automatically puts you into the flare.
> Allen

But that 40-knot headwind is still lifting the wing, even with
the airplane motionless, making it very easy for the elevator to lift
the tail. The airplane is almost flying.

Dan

[Allen[_1_]]

> wrote in message
oups.com...
>
> Allen wrote:
> > > wrote in message
> > ups.com...
> > >
> > > Allen wrote:
> > >
> > >> I once saw a pair of mechanics doing a full power run-up in a Maule.
> > >> They
> > >> were holding brakes on and forward elevator, the tail was about six
feet
> > >> in
> > >> the air standing still. So yes. Why do you separate the nosewheel
from
> > >> the tailwheel? They both fly with the same principles.
> > >>
> > >> Allen
> > >
> > > Aha, but you have to allow for the thrust line being so far
> > > above the drag line, which in this case is the ground where the wheels
> > > are locked. That thrust produces a pitching couple that raises the
tail
> > > much more effectively than the down-elevator. If the pilot holds full
> > > forward elevator at the start of the takeoff roll, the tails of most
> > > taildraggers won't come up until some considerable forward speed is
> > > attained, and then the tail is rising mostly because the centre of
> > > pressure of the wing, being behind the mains, is lifting it. Using
> > > forward elevator will lift the tail sooner but it sure is not entirely
> > > responsible for the rise.
> > > Wheelbarrowing is also mostly caused by too-fast landing
> > > speeds, not just forward elevator. It's worse with flaps down because
> > > the wing's CP is ahead of the mains and is raising the tail.
> > > Down-elevator isn't even necessary at high-enough speeds. The
> > > nosewheels of most trikes is closer to the ground than the mains in
> > > level flight attitude, and will contact first with the high airspeed
> > > reducing AOA.
> > >
> > > Dan (Instructor in taildraggers and trikes and a mechanic too)
> >
> > I have seen a Super Cub land with a 40 knot (or so) headwind and come to
a
> > complete stop, then raise the tail off the ground with the engine at
idle.
> > I see you point about the thrust affecting pitch though, used that all
the
> > time landing the Lear, as you bring the power levers to idle the nose
> > pitches up and automatically puts you into the flare.
> > Allen
>
> But that 40-knot headwind is still lifting the wing, even with
> the airplane motionless, making it very easy for the elevator to LIFT THE
TAIL. The airplane is almost flying.
>
> Dan
>
Ah ha, the answer to the OP's question.

Allen

[Peter Duniho]

> wrote in message
ps.com...
> Plus I'm pretty sure my statement was pretty odvious in it's direction
> to the original author... just like you said... your post had nothing
> to do with it. Sorry if I've caused irrperable offense.

It should be apparent by my reply that it was *not* obvious. You replied to
my post, rather than the one to which you were commenting, which made it
look very much like you were addressing my post (even though you weren't).

As far as your apology goes...there's no irreparable offense to apologize
for, but you could instead simply apologize for not quoting, and posting in
reply to the wrong post, causing confusion.

Thanks,
Pete

[Peter Duniho]

"Dan" > wrote in message
ups.com...
> Yes, the elevetor generates lift, negative lift, 99.9% of the time, in
> stable flight. If you look at most diagrams of aircraft forces, you
> will see the CG with a force vector down, then behind that the center
> of lift with a force vector upwards. Finally, the elevator is usually
> drawn with a force vector downwards as well.

In straight and level flight on most airplane designs, the elevator *does*
provide a downward-directed force. So that's what is put in diagrams of
aircraft forces by default. That doesn't mean that's what the elevator
always does.

> I would say there is a distinction between tailwheels and tricycle gear
> aircraft. On a tailwheel, the CG is behind the main gear, on a
> tricycle gear plane the CG is in front of the main gear.

In the air, the location of the CG relative to the main gear is entirely
irrelevant. Even on the ground, the location of the CG relative to the main
gear has nothing to do with what aerodynamic forces the elevator can
generate.

> Thanks for the example of the outside loop, I understand now. While
> observing the range of stabilator deflection on a PA28, it seems to be
> able to generate a _heck_ of a lot more downward force than upward
> force, but apparently upward force is possible as well.

I haven't looked closely, but I'm pretty sure that a typical design for a
horizontal stabilizer is to give it an angle of incidence that provides for
some preferred amount of downward force in straight and level cruise flight.
Assuming symmetrical deflection of the elevator up or down, this would limit
the upward force to something less than the downward force. Of course, this
design restriction could be avoided by providing greater downward deflection
by the elevator than upward.

Pete

[[email protected]]

Allen wrote:
> > wrote in message
> oups.com...
> >
> > Allen wrote:
> > > > wrote in message
> > > ups.com...
> > > >
> > > > Allen wrote:
> > > >
> > > >> I once saw a pair of mechanics doing a full power run-up in a Maule.
> > > >> They
> > > >> were holding brakes on and forward elevator, the tail was about six
> feet
> > > >> in
> > > >> the air standing still. So yes. Why do you separate the nosewheel
> from
> > > >> the tailwheel? They both fly with the same principles.
> > > >>
> > > >> Allen
> > > >
> > > > Aha, but you have to allow for the thrust line being so far
> > > > above the drag line, which in this case is the ground where the wheels
> > > > are locked. That thrust produces a pitching couple that raises the
> tail
> > > > much more effectively than the down-elevator. If the pilot holds full
> > > > forward elevator at the start of the takeoff roll, the tails of most
> > > > taildraggers won't come up until some considerable forward speed is
> > > > attained, and then the tail is rising mostly because the centre of
> > > > pressure of the wing, being behind the mains, is lifting it. Using
> > > > forward elevator will lift the tail sooner but it sure is not entirely
> > > > responsible for the rise.
> > > > Wheelbarrowing is also mostly caused by too-fast landing
> > > > speeds, not just forward elevator. It's worse with flaps down because
> > > > the wing's CP is ahead of the mains and is raising the tail.
> > > > Down-elevator isn't even necessary at high-enough speeds. The
> > > > nosewheels of most trikes is closer to the ground than the mains in
> > > > level flight attitude, and will contact first with the high airspeed
> > > > reducing AOA.
> > > >
> > > > Dan (Instructor in taildraggers and trikes and a mechanic too)
> > >
> > > I have seen a Super Cub land with a 40 knot (or so) headwind and come to
> a
> > > complete stop, then raise the tail off the ground with the engine at
> idle.
> > > I see you point about the thrust affecting pitch though, used that all
> the
> > > time landing the Lear, as you bring the power levers to idle the nose
> > > pitches up and automatically puts you into the flare.
> > > Allen
> >
> > But that 40-knot headwind is still lifting the wing, even with
> > the airplane motionless, making it very easy for the elevator to LIFT THE
> TAIL. The airplane is almost flying.
> >
> > Dan
> >
> Ah ha, the answer to the OP's question.
>
> Allen

Sort of. But when flying a taildragger, you soon learn that
the elevator's tail-raising ability isn't very strong at all. When we
teach normal takeoffs in the Citabria, we accelerate with the elevator
neutral (wherever it wants to be) until the tail rises about four
inches off the pavement, then begin applying back pressure to keep it
from coming up any more. By the time it flies off, you have
considerable up-elevator in just to keep the tail down in climb
attitude, and that force will be required, with reduction as speed
increases, until climb speed is reached and stabilized. At that time
the stabilizer's downforce will be strong enough to keep the airplane
in climb attitude.
If we applied no backpressure during takeoff, the tail would
rise alarmingly to level flight attitude all on its own. If solo, the
nose could get pretty low. The wing is lifting, and since the airplane
is designed to go nose-down when speed is low, it will do just that as
the wings take the weight off the wheels. When we do tail-high
takeoffs, we apply full forward stick to get the tail up much sooner,
but as speed builds backpressure will be needed at some point to
control the attitude.
Can't blame all the attitude changes on the elevator. The
wing's lift as opposed to the wheels placement also has a huge effect.
We have balanced airplane models we use to demonstrate these things to
the students. They can see the tail come up when we lift the wing at CP
with our fingers and wheels leave the table.


Dan