Crab, slips, and crossed controls

"Stealth Pilot" wrote in message
...
| On Mon, 22 Sep 2008 14:10:50 GMT, Robert Moore
| wrote:
|
| Stealth Pilot wrote
| Sideslips are a very useful tool because they allow you to
| substantially increase the drag, which makes you descent like a
| plumbers toolbag, but doesnt change the forward speed. so you have no
| increased risk of stalling as you wash off the height.
|
| What you have described is the "forward slip". Although control usage
| is the same in both, a "side slip" is used to correct for a crosswind,
| and a "forward slip" is used to descend more rapidly on final without
| having the airspeed increase. If one is not landing, I suppose that it
| would just be a "slip".
|
| Airliners normally do not use either because of the increased discomfort
| caused the passengers....both being uncoordinated flight.
|
| Amine wrote:
| PS: I have read about many cases of jetliners that had to make
| emergency descents at abnormally high speeds, but the AC143 seems the
| only one to have used the sideslip.
|
| AC 143 was constrained by "touchdown speed" runway length. An "emergency
| descent" has no such constraint and therefore is able to use the
| aircraft's maximum certificated speed for the descent...far in excess of
| what would be possible in an approach/landing situation.
|
| In an engine failure situation, keep it as high as possible for as long
| as possible to insure that the field can be reached, and then slip as
| much as required to lose the excess altitude without gaining airspeed.
|
| Bob Moore
| Flight Instructor ASE-IA
| ATP B-707 B-727
| PanAm (retired)
|
| in my country the manouver I describe is always called a side slip.
|
| side slips are used as I indicate to dirty up the aircraft
| aerodynamically.
| they can be used to counter a crosswind but the crabbed approach is
| preferred because it doesnt change the approach profile.
|
| it is a side slip.
|
| youalls mileage may vary :-)
|
| Stealth Pilot

Yeah, but you're a dumb ass.

"Mick" #$$#@%%%.^^^ wrote in :


"Stealth Pilot" wrote in message
...
| On Mon, 22 Sep 2008 14:10:50 GMT, Robert Moore
| wrote:
|
| Stealth Pilot wrote
| Sideslips are a very useful tool because they allow you to
| substantially increase the drag, which makes you descent like a
| plumbers toolbag, but doesnt change the forward speed. so you have
| no increased risk of stalling as you wash off the height.
|
| What you have described is the "forward slip". Although control
| usage is the same in both, a "side slip" is used to correct for a
| crosswind, and a "forward slip" is used to descend more rapidly on
| final without having the airspeed increase. If one is not landing, I
| suppose that it would just be a "slip".
|
| Airliners normally do not use either because of the increased
| discomfort caused the passengers....both being uncoordinated flight.
|
| Amine wrote:
| PS: I have read about many cases of jetliners that had to make
| emergency descents at abnormally high speeds, but the AC143 seems
| the only one to have used the sideslip.
|
| AC 143 was constrained by "touchdown speed" runway length. An
| "emergency descent" has no such constraint and therefore is able to
| use the aircraft's maximum certificated speed for the descent...far
| in excess of what would be possible in an approach/landing
| situation.
|
| In an engine failure situation, keep it as high as possible for as
| long as possible to insure that the field can be reached, and then
| slip as much as required to lose the excess altitude without gaining
| airspeed.
|
| Bob Moore
| Flight Instructor ASE-IA
| ATP B-707 B-727
| PanAm (retired)
|
| in my country the manouver I describe is always called a side slip.
|
| side slips are used as I indicate to dirty up the aircraft
| aerodynamically.
| they can be used to counter a crosswind but the crabbed approach is
| preferred because it doesnt change the approach profile.
|
| it is a side slip.
|
| youalls mileage may vary :-)
|
| Stealth Pilot

Yeah, but you're a dumb ass.




Nope


Bertie

On Sep 22, 7:10*am, Amine wrote:
Hey,

Some of you may have heard of Air Canada 143 [http://www.youtube.com/
watch?v=dfJIpA2gv1g] which ran out of fuel in mid air and had to make
an emergency descent at velocities way above the normal limits. The
pilot's makeshift technique was to engage a sideslip to decelerate the
aircraft (which by then had no flaps, and only minimal hydraulics).

Now I thought that sideslips (and crabs--whatever the difference
between the two is...) were only to be used to handle crosswinds. I
didn't read anywhere that they could be used to bleed excessive speed,
although it makes sense from an aerodynamics perspective. Anyone out
there used sideslips for anything other than crosswind approaches?

PS: I have read about many cases of jetliners that had to make
emergency descents at abnormally high speeds, but the AC143 seems the
only one to have used the sideslip.

Slips were in common use for bringing an aircraft down in the days
before flaps, and were taught for that purpose when learned to fly in
the 70's. They work very well. Is that no longer being taught?
--
Gene Seibel
Gene & Sue's Flying Machine - http://pad39a.com/gene/
Because we fly, we envy no one.

Gene Seibel wrote:
On Sep 22, 7:10?am, Amine wrote:
Hey,

Some of you may have heard of Air Canada 143 [http://www.youtube.com/
watch?v=dfJIpA2gv1g] which ran out of fuel in mid air and had to make
an emergency descent at velocities way above the normal limits. The
pilot's makeshift technique was to engage a sideslip to decelerate the
aircraft (which by then had no flaps, and only minimal hydraulics).

Now I thought that sideslips (and crabs--whatever the difference
between the two is...) were only to be used to handle crosswinds. I
didn't read anywhere that they could be used to bleed excessive speed,
although it makes sense from an aerodynamics perspective. Anyone out
there used sideslips for anything other than crosswind approaches?

PS: I have read about many cases of jetliners that had to make
emergency descents at abnormally high speeds, but the AC143 seems the
only one to have used the sideslip.

Slips were in common use for bringing an aircraft down in the days
before flaps, and were taught for that purpose when learned to fly in
the 70's. They work very well. Is that no longer being taught?

Sure they are still being taught, though the emphasis these days
is in crosswind landings. I think I only did one or two to lose
altitude while a student, the instructors comment being if you
plan properly you seldom need to do this in an airplane with flaps.


--
Jim Pennino

Remove .spam.sux to reply.

wrote:
Gene Seibel wrote:
On Sep 22, 7:10?am, Amine wrote:
Hey,

Some of you may have heard of Air Canada 143 [http://www.youtube.com/
watch?v=dfJIpA2gv1g] which ran out of fuel in mid air and had to make
an emergency descent at velocities way above the normal limits. The
pilot's makeshift technique was to engage a sideslip to decelerate the
aircraft (which by then had no flaps, and only minimal hydraulics).

Now I thought that sideslips (and crabs--whatever the difference
between the two is...) were only to be used to handle crosswinds. I
didn't read anywhere that they could be used to bleed excessive speed,
although it makes sense from an aerodynamics perspective. Anyone out
there used sideslips for anything other than crosswind approaches?

PS: I have read about many cases of jetliners that had to make
emergency descents at abnormally high speeds, but the AC143 seems the
only one to have used the sideslip.
Slips were in common use for bringing an aircraft down in the days
before flaps, and were taught for that purpose when learned to fly in
the 70's. They work very well. Is that no longer being taught?

Sure they are still being taught, though the emphasis these days
is in crosswind landings. I think I only did one or two to lose
altitude while a student, the instructors comment being if you
plan properly you seldom need to do this in an airplane with flaps.



In the mid to late 80's I was doing the first BFR away from my
home-drome and with a CFI I didn't really know and who was younger than
I was (he couldn't have been over 20). I hadn't flown much while at
college and had never landed at the airport where I was getting review.
During my first pattern I was on final and realized I was high and put
the plane into a slip to loose about 100-150'. From the reaction of the
CFI you would have thought I'd just told him his sister was great in
bed. He took over the plane and called a go around. He babbled for a
while about uncoordinated flight and then I realized he had never been
taught to slip for altitude. I told him I'd not ever do it again and we
finished the BFR.

Once we were back on the ground and with his boss close by I left him
reading about them in the FAA Airplane Flying Handbook they had in the
office.

Gig 601Xl Builder wrote in
m:

Once we were back on the ground and with his boss close by I left
him reading about them in the FAA Airplane Flying Handbook they
had in the office.

That's incredible. When I took my CFI Ride, I had to demonstrate a
maximum effort forward slip on final. Kicked out when I was over the
fence and hit the numbers. Seems as if your instructor didn't know the
difference between a slip and a skid.

--

On Sep 23, 8:17 am, John Godwin wrote:

That's incredible. When I took my CFI Ride, I had to demonstrate a
maximum effort forward slip on final. Kicked out when I was over the
fence and hit the numbers. Seems as if your instructor didn't know the
difference between a slip and a skid.

A number of aircraft that I've flown do not have flaps and the
sideslip was an everyday common maneuver .
I found the practice was frowned upon in the modern aircraft as there
were claims that the elevators were shielded and all manner of
problems could develop

John Godwin wrote:
Gig 601Xl Builder wrote in
m:

Once we were back on the ground and with his boss close by I left
him reading about them in the FAA Airplane Flying Handbook they
had in the office.

That's incredible. When I took my CFI Ride, I had to demonstrate a
maximum effort forward slip on final. Kicked out when I was over the
fence and hit the numbers. Seems as if your instructor didn't know the
difference between a slip and a skid.


Since this was over 20 years ago I often wonder if this guy is sitting
in the left seat of a 747 somewhere. It kind of scares me.

wrote:
Sure they are still being taught, though the emphasis these days
is in crosswind landings. I think I only did one or two to lose
altitude while a student, the instructors comment being if you
plan properly you seldom need to do this in an airplane with flaps.

Exactly. My instructor's comment was that we were practicing it in case
the flaps failed. And because it's in the PTS, of course.

.... Alan
--
Alan Gerber
PP-ASEL
gerber AT panix DOT com

Alan Gerber wrote in news:gb9s8n$ngu$1
@reader1.panix.com:

wrote:
Sure they are still being taught, though the emphasis these days
is in crosswind landings. I think I only did one or two to lose
altitude while a student, the instructors comment being if you
plan properly you seldom need to do this in an airplane with flaps.

Exactly. My instructor's comment was that we were practicing it in case
the flaps failed. And because it's in the PTS, of course.

There's value in that, but they're also more useful than flaps in the event
of an engine failure. You get better glide control with them and you can
always use the flaps at the end of the glide..


Bertie