Turn to Final - Keeping Ball Centered

Why does no one distinguish between a level turn (constant acceleration into
the center of the arc, which increases load factor) and the load factor in
which the same angle of bank exists in a descent? When descending you are
moving away from the center of the in the vertical direction which means
less acceleration towards the center in the original plane (geometric).

You can feel the load factor difference in the seat of your pants when
descending, compared to maintaining level flight in a steep bank. I don't
understand how people can claim the load factor is the same descending and
turning for example in a 600 fpm descent.

It is no different than twirling a weight at the end of a string. Takes
more energy to maintain the string at a higher horizontal angle.



2. The stall speed goes up as the square root of the secant (1/cosine)
of the angle of bank.

At:
30 deg: 1.07
45 deg: 1.19
60 deg: 1.41
75 deg: 1.97

writes:
Why does no one distinguish between a level turn (constant acceleration into
the center of the arc, which increases load factor) and the load factor in
which the same angle of bank exists in a descent? When descending you are
moving away from the center of the in the vertical direction which means
less acceleration towards the center in the original plane (geometric).

The center just becomes a line in that case, doesn't it? You end up
with the same centripetal force needed towards that center line in
order to turn.

You can feel the load factor difference in the seat of your pants when
descending, compared to maintaining level flight in a steep bank. I don't
understand how people can claim the load factor is the same descending and
turning for example in a 600 fpm descent.

Nosing over into a descent does temporarily reduce load factor, but as
soon as you're established in a constant descent, you're back at the
same 1g load. Gravity is *acceleration*, not *velocity*.

--
James Carlson, Solaris Networking
Sun Microsystems / 35 Network Drive 71.232W Vox +1 781 442 2084
MS UBUR02-212 / Burlington MA 01803-2757 42.496N Fax +1 781 442 1677

I am sorry to belabor this point, but hopefully I will understand it better
if you have the patience to help me.

I understand that gravity's acceleration is indistinguishable from any other
acceleration in a frame of reference, and that it is 1g in a constant
descent or climb. I also understand that a turn is accelerating to the
center of the arc whether it is descending, level, or climbing.

Are you saying the force vector sums are equivalent when comparing level
turns at the same bank angle to constant rate descent? In other words, that
a 2g load factor occurs in a 60 degree bank regardless of whether remaining
level or a constant rate of descent and that the stall speeds are identical?
The engine power required is plainly different.

Thanks.



The center just becomes a line in that case, doesn't it? You end up
with the same centripetal force needed towards that center line in
order to turn.

Nosing over into a descent does temporarily reduce load factor, but as
soon as you're established in a constant descent, you're back at the
same 1g load. Gravity is *acceleration*, not *velocity*.

--
James Carlson, Solaris Networking

This is bugging me so much, I am going to climb to altitude and test it
myself next time I fly.

It will be good practice anyway. The problem will be that the airspeed
indicator isn't that accurate at those slow speeds but it should be
equivalent in both level and descending flight stall breaks. The hard part
will be maintaining a constant descent rate while in a steep bank and not
letting it wander up and down.

I believe you guys are correct, I just can't understand the reason behind
it. Nothing like a real experiment to prove the theory if I can't
understand the physics behind it.

wrote in news:mrTBj.72580$yE1.11316@attbi_s21:

Why does no one distinguish between a level turn (constant
acceleration into the center of the arc, which increases load factor)
and the load factor in which the same angle of bank exists in a
descent?

Because it's negligable.


Bertie

skym wrote:
While making a turn to base and final recently, I was aware that I was
going to be wide with my normal turn from downwind through base to
final, so I banked more to keep as close to the runway centerline as
possible. I kept thinking about the infamous and usually fatal stall/
spin by some pilots in this situation, I kept thinking that if I keep
the ball centered, even with a very steep bank, that I would be ok and
not auger in. Some of you instructors and old pros...is this correct?
(Not that I intend to make it a practice.)

I hesitate to add to this discussion because
I'm not an instructor, just a rather slow
student who's not qualified to give advice
that might kill someone.

My instructor carefully pointed out the difference
between a stall on final as opposed to a snap
spin. A stall might be recoverable with no more
damage than a looseness of the bowels whereas
a spin could really fsk up your day.

The gist of his advice was that if you keep the
turn coordinated or even add a little extra
aileron, the up wing will have to come all the
way down through level before it will spin,
giving you time get the nose down and level the
wings before that spin can develop.

OTOH, a flat turn to final can quickly develop
into a spin before you can get it under control.

Jim Stewart wrote:
skym wrote:
While making a turn to base and final recently, I was aware that I was
going to be wide with my normal turn from downwind through base to
final, so I banked more to keep as close to the runway centerline as
possible. I kept thinking about the infamous and usually fatal stall/
spin by some pilots in this situation, I kept thinking that if I keep
the ball centered, even with a very steep bank, that I would be ok and
not auger in. Some of you instructors and old pros...is this correct?
(Not that I intend to make it a practice.)

I hesitate to add to this discussion because
I'm not an instructor, just a rather slow
student who's not qualified to give advice
that might kill someone.

My instructor carefully pointed out the difference
between a stall on final as opposed to a snap
spin. A stall might be recoverable with no more
damage than a looseness of the bowels whereas
a spin could really fsk up your day.

The gist of his advice was that if you keep the
turn coordinated or even add a little extra
aileron, the up wing will have to come all the
way down through level before it will spin,
giving you time get the nose down and level the
wings before that spin can develop.

OTOH, a flat turn to final can quickly develop
into a spin before you can get it under control.

Any stall in the pattern can be a serious problem. You need stall and
yaw rate to induce spin. Of all the possible scenarios to have if you
manage to be ham handed enough to get into a stall in the pattern, a
stall from a slip is the most anti-spin. Then comes a coordinated stall
with no yaw induced at the break, and finally the worst condition is a
stall from a skidding turn. No matter which scenario, angle of attack
MUST be lowered, and any yaw rate MUST be neutralized IMMEDIATELY!


--
Dudley Henriques

Dudley Henriques wrote:
Jim Stewart wrote:
skym wrote:
While making a turn to base and final recently, I was aware that I was
going to be wide with my normal turn from downwind through base to
final, so I banked more to keep as close to the runway centerline as
possible. I kept thinking about the infamous and usually fatal stall/
spin by some pilots in this situation, I kept thinking that if I keep
the ball centered, even with a very steep bank, that I would be ok and
not auger in. Some of you instructors and old pros...is this correct?
(Not that I intend to make it a practice.)

I hesitate to add to this discussion because
I'm not an instructor, just a rather slow
student who's not qualified to give advice
that might kill someone.

My instructor carefully pointed out the difference
between a stall on final as opposed to a snap
spin. A stall might be recoverable with no more
damage than a looseness of the bowels whereas
a spin could really fsk up your day.

The gist of his advice was that if you keep the
turn coordinated or even add a little extra
aileron, the up wing will have to come all the
way down through level before it will spin,
giving you time get the nose down and level the
wings before that spin can develop.

OTOH, a flat turn to final can quickly develop
into a spin before you can get it under control.

Any stall in the pattern can be a serious problem. You need stall and
yaw rate to induce spin. Of all the possible scenarios to have if you
manage to be ham handed enough to get into a stall in the pattern, a
stall from a slip is the most anti-spin. Then comes a coordinated stall
with no yaw induced at the break, and finally the worst condition is a
stall from a skidding turn. No matter which scenario, angle of attack
MUST be lowered, and any yaw rate MUST be neutralized IMMEDIATELY!

You put it better than I could. Thanks.

"Dudley Henriques" wrote in message
...
Any stall in the pattern can be a serious problem. You need stall and yaw
rate to induce spin. Of all the possible scenarios to have if you manage
to be ham handed enough to get into a stall in the pattern, a stall from a
slip is the most anti-spin. Then comes a coordinated stall with no yaw
induced at the break, and finally the worst condition is a stall from a
skidding turn. No matter which scenario, angle of attack MUST be lowered,
and any yaw rate MUST be neutralized IMMEDIATELY!


--
Dudley Henriques

Can you please elaborate on the stall from a slip condition.

I am fond of the bush pilot style pattern, using180 degree constant slipping
turn to final and would also be interested in your thoughts on these.

TIA
Happy landings,

Private wrote:
"Dudley Henriques" wrote in message
...
Any stall in the pattern can be a serious problem. You need stall and yaw
rate to induce spin. Of all the possible scenarios to have if you manage
to be ham handed enough to get into a stall in the pattern, a stall from a
slip is the most anti-spin. Then comes a coordinated stall with no yaw
induced at the break, and finally the worst condition is a stall from a
skidding turn. No matter which scenario, angle of attack MUST be lowered,
and any yaw rate MUST be neutralized IMMEDIATELY!


--
Dudley Henriques

Can you please elaborate on the stall from a slip condition.

I am fond of the bush pilot style pattern, using180 degree constant slipping
turn to final and would also be interested in your thoughts on these.

TIA
Happy landings,


I see no problems at all with a constant slipping turn approach, and in
fact favor this type myself when flying prop fighters such as the P51
and the F8F and even the Pitts Spcial due to the better visibility
during these approaces over the nose and ahead and inside the turn as
the approach is flown.

Slips are basically anti spin. You can actually increase the angle of
attack available in front of your critical angle of attack as you deepen
a slip. The ultimate example of this would be knife edge flight where
forward stick pressure is required to reduce angle of attack to near the
0 lift point on the wing.
Of course you won't be doing any knife edge flight on a slipping
approach, but the slip you are in is still anti spin.
Even if you stall the airplane in a slip, the likely result will be a
break over the top, which is a much better stall break than a skidding
stall break which will usually break under the bottom. You have much
more time to recover from a slipping stall entry than you do from a skid
entry.

The bottom line is that it's quite safe to fly a slipping approach if
you are aware, flying properly and watching what you are doing.

--
Dudley Henriques