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PRB
September 7th, 2009, 10:31
So, I’m watching the “Great Planes” marathon on the Military channel. On now, the F-100 Super Sabre. The host is asking questions of a former F-100 pilot, who says this: “In the pattern, you never moved the stick, you held the stick rock-steady. You used the rudders to maneuver the plane in the pattern.” What?? I’ve never heard of such a crazy thing. Could that be true?
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There was some WIP pics of an F-100 “under construction” by somebody here. They need to see this. When it comes out I’m going to try to fly around the pattern using only the rudders! :icon_lol:

Quicksand
September 7th, 2009, 10:36
Amen! Bring on a Hun for FSX!:medals::icon29::guinness::applause::jump:

Lateral-G
September 7th, 2009, 10:37
So, I’m watching the “Great Planes” marathon on the Military channel. On now, the F-100 Super Sabre. The host is asking questions of a former F-100 pilot, who says this: “In the pattern, you never moved the stick, you held the stick rock-steady. You used the rudders to maneuver the plane in the pattern.” What?? I’ve never heard of such a crazy thing. Could that be true?
<o:p></o:p>
There was some WIP pics of an F-100 “under construction” by somebody here. They need to see this. When it comes out I’m going to try to fly around the pattern using only the rudders! :icon_lol:

Sort of goes against more modern fighters...you don't touch the rudder. You keep your feet planted flat on the floor. Most rudder input is prohibited once you're flying.

-G-

VFR Alexander
September 7th, 2009, 10:50
So, I’m watching the “Great Planes” marathon on the Military channel. On now, the F-100 Super Sabre. The host is asking questions of a former F-100 pilot, who says this: “In the pattern, you never moved the stick, you held the stick rock-steady. You used the rudders to maneuver the plane in the pattern.” What?? I’ve never heard of such a crazy thing. Could that be true?
<o:p></o:p>
There was some WIP pics of an F-100 “under construction” by somebody here. They need to see this. When it comes out I’m going to try to fly around the pattern using only the rudders! :icon_lol:
Probably because it had a tendency to roll easily.

SkippyBing
September 7th, 2009, 11:23
I believe the Phantom was also flown with a lot of pedal input, probably something to do with secondary effects of controls and the early swept wing jets?

VFR Alexander
September 7th, 2009, 13:12
I believe the Phantom was also flown with a lot of pedal input, probably something to do with secondary effects of controls and the early swept wing jets?


Yup, same reason as the Hun, although for the F-4 they just put the dihedral in.

tigisfat
September 7th, 2009, 13:34
I find that hard to believe. There are many pilots and maintainers who are not only full of it, they forget what they're talking about over the years and start telling the legend. It may be true, but it's unlikely. If I tried to could count the number of myths I've heard about B-1s, It'd take years.

I once watched a TV special where a B-52 pilot was being interviewed. He told the cameraman that long sorties in an ACES II ejection seat were like sitting on a 2X4 for 12 hours. I don't know where or why he came up with that one. I sit on an ejection seat every day, and it's nothing like sitting on a 2X4.

From time to time I fly an Aeronca Champ, and I fly it primarily with rudders. I start it leaning over wth the pedals and then I coordinate my turns with the stick. The Champ also has very low wing loading, and the F-100 has extremely high wing loading. High AOA and wing loading in the pattern would always mean that yaw inputs could equal snap-roll like phenomena; the same reason that many modern military jets discourage the use of anything but correcting rudder.

SirBenn21
September 7th, 2009, 13:52
So, I’m watching the “Great Planes” marathon on the Military channel. On now, the F-100 Super Sabre. The host is asking questions of a former F-100 pilot, who says this: “In the pattern, you never moved the stick, you held the stick rock-steady. You used the rudders to maneuver the plane in the pattern.” What?? I’ve never heard of such a crazy thing. Could that be true?
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There was some WIP pics of an F-100 “under construction” by somebody here. They need to see this. When it comes out I’m going to try to fly around the pattern using only the rudders! :icon_lol:

My instructer did a whole circuit in a C172 with only rudder and trim as a demo. I was also amazed, but it's true. I'm not sure about all aircraft, but it should be.
One of my friends said that his mate did the same to prove to his wife that it can be done. He flew from Germany to the UK. She just refused to let him land that way! :)

Ben

Moses03
September 7th, 2009, 14:07
My Uncle owned a Mooney 201 and I remember him telling me that on long flights he would make course corrections with rudder only. Not being a real life pilot I thought that sounded odd but I guess not after reading some replies here.

Moses

Bone
September 7th, 2009, 14:30
With the right amount of skill, you can fly a plane with many unusual control and power inputs. However, using only rudder input to turn a swept wing jet brings you that much closer to an unhappy ending...especially in the pattern. From what I've heard about F-100's and F-4's, it takes very little stick input to initiate a turn. Maybe the person who sandbagged the ride in this story didn't see the stick move much, because the stick didn't need to move much.

SirBenn21
September 7th, 2009, 14:32
Well here is an idea. :iidea:

Start up FSX and have a go and see how possible it is via a Flight Sim.

Ben

Panther_99FS
September 7th, 2009, 14:56
I believe the F-100 WiP pictures were either by AlphaSim or Michael Davies.....

I could be wrong though...:kilroy:

Slug Flyer
September 7th, 2009, 15:03
Mr. Davies is now developing his F-100 for the RAZBAM label.

PRB
September 7th, 2009, 15:09
Well here is an idea. :iidea:

Start up FSX and have a go and see how possible it is via a Flight Sim.

Ben

Ok, I tried it with the Alphasim F-11 Tiger. It’s the closest thing I have in FSX to an F-100. It worked! And it was kind of fun and challenging. I felt like that DC-10 pilot who had to land without hydraulics in Sioux City Iowa some time ago! I had to use the stick for pitch control, but I never touched the ailerons. I don’t know why I would want to do such a thing as a matter of normal procedures. It’s much easier to land the plane if you can use the ailerons! :icon_lol: I’ve heard of using only the rudders (or only ailerons) to make small course corrections on long flights, but this pilot made it sound like he landed this way "normally." Not sure what it prooves, in any case. I think the real planes are a bit harder to land than the ones in FSX...

Bone
September 7th, 2009, 15:32
I don’t know why I would want to do such a thing as a matter of normal procedures.

You wouldn't, so good thinking.

tigisfat
September 7th, 2009, 16:36
With the right amount of skill, you can fly a plane with many unusual control and power inputs.
Exactly.


Maybe the person who sandbagged the ride in this story didn't see the stick move much, because the stick didn't need to move much.


That sounds a lot more likely.

tigisfat
September 7th, 2009, 16:53
re: rudder corrections on long flights;

That's been my technique since I started flying instruments. I'm sure there are aircraft out there that you can't or shouldn't do this in, but it works just fine when only one or two degree corrections are needed. I usually use the rudder to make one or two degree corrections, then I keep the turn indicator zeroed out with rudders. I'm a big fan of power/trim instrument flying. I'm sure it gets harder when you're talking about large aircraft that have a wide range of weights they fly at.

falcon409
September 7th, 2009, 16:58
Mr. Davies is now developing his F-100 for the RAZBAM label.
That's gratifying to know, especially if I live to see the release. Over the past few years, from time to time threads are started asking what aircraft folks would like to see developed. My answer has always been and will continue to be the F-100 Super Saber. The ONLY century aircraft almost totally ignored and every time I suggest that aircraft, it's as though I'm speaking a foreign language as the post is never mentioned and basically ignored, never to be mentioned again. I hope this aircraft gets the attention it so richly deserves.

PRB
September 7th, 2009, 17:28
... Maybe the person who sandbagged the ride in this story didn't see the stick move much, because the stick didn't need to move much.

Well, the person who said all this about the rudders was the pilot. At least there was no question that the "Great Planes" production people told us he was a pilot. 200 combat missions over Vietnam, pulling 6.5 Gs after dropping bombs, using peripheral vision to aim the refueling probe, mounted on the right wing, into the tanker. He said he lands it "just like my Super Decathalon". So, unless the Great Planes people have been had, I would have to say he was the pilot.

It's possible he meant using the rudder for small corrections on final, but even that really makes no sense (to me anyway) if you have a perfectly good control stick. But he did say "in the landing pattern", which implies to me the square shaped pattern over the airport. It's interesting to me that this doesn't make any sense to the pilots here either. I'll bet he was refering to some querk of the F-100, and did it poorly. I wish we had an F-100 pilot here.

fliger747
September 7th, 2009, 19:08
Having a lot of time in swept wing jets.... This seems a bit unlikely, however before high lift augmentation became really effective in more modern aircraft, some of these planes flew approach at pretty high angles of attack, in which area rough handling of the ailerons can cause serious issues! Many modern swept wing incorporate spoilers to assist in roll authority which avoids this issue somewhat. Tactical types are known for rudder induced roll coupling.

Probably an issue of not slamming the stick around, a sin of which most of the fighter jocks I have flown with are guilty of.

Cheers: t

dhazelgrove
September 7th, 2009, 22:24
I believe the Phantom was also flown with a lot of pedal input, probably something to do with secondary effects of controls and the early swept wing jets?

"When she buffets, use your boots!"

Dave

kilo delta
September 8th, 2009, 01:52
Rudder?...what's that?

Bank an' Yank FTW :monkies: :icon_lol:

VFR Alexander
September 8th, 2009, 03:13
Well, the person who said all this about the rudders was the pilot. At least there was no question that the "Great Planes" production people told us he was a pilot. 200 combat missions over Vietnam, pulling 6.5 Gs after dropping bombs, using peripheral vision to aim the refueling probe, mounted on the right wing, into the tanker. He said he lands it "just like my Super Decathalon". So, unless the Great Planes people have been had, I would have to say he was the pilot.

It's possible he meant using the rudder for small corrections on final, but even that really makes no sense (to me anyway) if you have a perfectly good control stick. But he did say "in the landing pattern", which implies to me the square shaped pattern over the airport. It's interesting to me that this doesn't make any sense to the pilots here either. I'll bet he was refering to some querk of the F-100, and did it poorly. I wish we had an F-100 pilot here.


Well, the host of the show is reachable online, although that may be a bit awkward. :monkies:

jmig
September 8th, 2009, 05:43
OK, I am relying on almost 30 year old memories, so I could be mistaken.

1. The B-52 did not use the ACESII seat. I forget the make and model but it was one of the older model seats. It was not comfortable to sit in for long flights (until your butt became so numb you didn't notice it) but it wasn't a 2X4. LOL

2. The reason you didn't have to use the rudder much in the F-4 was because it was connected to the control stick in a manner to provide coordinated turns.

The rudder was used at times to yaw the nose or do barrel rolls, for instance. A little top rudder in a hard turn would keep your nose up. During instrument approaches a slight left or right of course could be corrected with the rudder. The rudder was also used in BFM to keep your nose on the enemy airplane.

3. The F-4, T-38, and if I am not mistaken all sweptwing fighters of that era were pulled through the turn. A normal GA type of wing will automatically gain more lift on the upwing and push it into a turn. Not so the supersonic wings of the Cold War era. If you banked one of these airplanes it would, for the most part, continue to fly straight but banked.

So on the final turn, you rolled off the perch by rolling the airplane into the turn with the control stick, let the nose drop, then pulled the airplane through the descending turn with stick back pressure. Bank would be used to control the turn rate or radius.

I often used a touch of rudder to align the nose with the centerline of the runway on short final.

Bone
September 8th, 2009, 06:31
I often used a touch of rudder to align the nose with the centerline of the runway on short final.

Yep. I do this, and everyone I've ever flown with does this...keeps from side-loading the tires and struts. I have an anecdote about the B-52 ejection seat. My dad flew the B-52D (165 Arc Light missions), and when I was in college I had an opportunity to buy a surplus B-52 ejection seat. I told my dad about it, and that I was going to modify it to be a desk chair. He went off on a tangent about how uncomfortable "that D&mned seat" was, and that I would never graduate from college if I had to sit in it to do homework.

oakfloor
September 8th, 2009, 07:02
Dont belive everything you hear on that program, I have heard a few mistakes here and there.

fliger747
September 8th, 2009, 09:07
T-38? Possibly not a swept wing fighter...

All Aircraft will require up elevator to make a level turn. This is much more apparent in the higher G turns made by high speed aircraft. Even hand flying the 747-400 in a steep turn (45 deg) significant backpressure is required, enough that trimming may be helpful. Even the rather slow Super Cub requires a lot of aft stick in a steep turn. However back stick should always setoff a warning in your head, at some point you are reaching a very high angle of attack and a departure from controled flight can be expected.

I fly with a lot of F4 drivers and will have to ask them about the rudders....

Cheers: t

Bone
September 8th, 2009, 09:42
T-38? Possibly not a swept wing fighter...

All Aircraft will require up elevator to make a level turn. This is much more apparent in the higher G turns made by high speed aircraft. Even hand flying the 747-400 in a steep turn (45 deg) significant backpressure is required, enough that trimming may be helpful. Even the rather slow Super Cub requires a lot of aft stick in a steep turn. However back stick should always setoff a warning in your head, at some point you are reaching a very high angle of attack and a departure from controled flight can be expected.

I fly with a lot of F4 drivers and will have to ask them about the rudders....

Cheers: t

JMIG flew the T-38 and RF-4, but I guess now you have more conversation fodder for one of those circadian rythym killing long hauls, hehe.

jmig
September 8th, 2009, 10:05
T-38? Possibly not a swept wing fighter...

I used swept wing fighter to describe the wing because someone else did. The leading edge of the T-38 is swept rearward. However, the airfoil of the wind is what mostly affects its turning characteristics. Unlike the thick wings of the 747 or Piper Cub the fighter wing uses angle of attack to generate its lift. The positives here are less drag and the ability to fly upside down as well as upright.

A Piper Cub (and I assume 747) wings when banked will generate more lift on the higher wing. This greater lift is what causes the airplane to want to naturally turn in the direction of the lower wing. Not so with the thin fighter wing, or at lease to a much smaller degree.

The aircraft must literally be pulled through the turn. Releasing back pressure during a turn will unload the aircraft, stop the turn and allow it to accelerate, all the while banked.

Cheers: t



...All Aircraft will require up elevator to make a level turn...



This is true. The backpressure compensates for the lost of lift. However, in an aircraft such as the T-38 or F-4. Banking will do nothing much more than roll the aircraft. The sequence was to roll then pull.



...However back stick should always setoff a warning in your head, at some point you are reaching a very high angle of attack and a departure from controled flight can be expected.

Cheers: t

Many early hard wing fighter aircraft, such as the T-38 were actually in a slight buffet during the final turn. I can still remember the slight shaking of the stick. You had to be careful not to depart.

Later leading edge flaps and boundary layer air flow over the wing helped to make the final turn easier and safer.

I lost two friends when the pilot departed control flight at low altitude due to an accelerated stall.


Again, I am relying on my memory of 30 years ago. So, I could be wrong.

dadmod
September 8th, 2009, 18:05
Ah, memories. I was a T-38 IP in the late 60's and can identify with JMIGs recollections. The 38 didn't turn all that well and would buffet easily...actually had to ride the buffet (at times) to be efficient. Buffeting in the final turn was a no-no for students in my day...had to be very careful with that. I was ok with fellow pilots getting a wee burble in a tight pattern but remained alert.
Don't recall using rudder much...ok for minor lateral control in trail, etc. Would demo rudder only clover leafs and a gear down rudder role to point out the increased rudder travel with gear down...again with care not to over stress anything.
And my disclaimer now...relying on my memory of ~40 years ago...:kilroy:
Could be wrong...

tigisfat
September 8th, 2009, 19:53
All Aircraft will require up elevator to make a level turn.


While I definitely respect your aeronautical qualifications and experience as greater than my own, I think that's a little too general of a statement to make.

An aircraft with the right amount of positive dihedral (sometimes tuned to the right amount for a standard-rate turn) will not require any flight control deflection to stay level or be pulled throughout the turn. Varying angles of bank produce different amount and kinds of lift. We must not forget that the horizontal component of lift turns an aircraft, even if you bank to 80 degrees and walk the jet out to 6 g's. There are several aircraft that immediately come to mind that don't require correction; the Beech Staggerwing is one and I know that the average Piper Warrior can turn at standard rate and maintain altitude with no elevator correction.

fsafranek
September 8th, 2009, 22:35
Mr. Davies is now developing his F-100 for the RAZBAM label.

I get the impression from reading in another forum that that fell through.
:ernae:

fliger747
September 8th, 2009, 22:48
Gee whiz.... I have flown a lot of different aircraft, including the Piper Warrior (My dad owned one). A standard rate of turn in a Warrior isn't much of a turn. But if ya want to keep the altitude within 5 feet, ya better compensate for the loss of the verticle component of lift ( I got my instrument ticket in one lo some 37 years ago...). Speaking of dihedral the down turn wing does increase it's lift component, but the up turn one looses some, so there is no resultant compensatory increase in the verticle lift component.......

My mechanic does an annual on a beautiful Staggerwing every Spring. I can see no particular reason why such might be true.

For those that are interested, I suggest "Aerodynamics for Naval Aviators", which includes my Marine compatriots... so it is generally written in English.

You are going to have to explaine to me (equations are fine) just why no compensatory AOA is needed to increase the CL when some of the lift component is diverted to the side to produce a turn, any turn. I did suffer through a lot of physics in under grad and grad school.....

Cheers: t.

DaveQ
September 9th, 2009, 02:20
That's gratifying to know, especially if I live to see the release. Over the past few years, from time to time threads are started asking what aircraft folks would like to see developed. My answer has always been and will continue to be the F-100 Super Saber. The ONLY century aircraft almost totally ignored and every time I suggest that aircraft, it's as though I'm speaking a foreign language as the post is never mentioned and basically ignored, never to be mentioned again. I hope this aircraft gets the attention it so richly deserves.

The other Century series aircraft almost totally ignored is the F-101. Alphasim's version is well past its sell-by date and, although it handles well enough in FSX, the textures are primitive compared to more modern offerings. I for one would like to see an FSX-native One-O-Wonder as well as a Hun before the Grim Reaper comes for me!!:engel016:

DaveQ

PRB
September 9th, 2009, 04:53
Ok, I got the scoop from a former co-worker of mine, Vito Tomasino, who flew F-100s. This is what he said:

"The F-100 pilot was no doubt referring to the final approach phase of the landing pattern where the aircraft is flying at near stall speed and a high angle of attack just prior to touchdown. The pitchout to downwind and the base turn would still require coordinated stick and rudder technique, as would most other flight situations.

However, you are correct in relating it to AOA rather than airspeed. In the F-100, with its highly swept wings, if ailerons are used at high AOA, regardless of the airspeed, it would induce adverse yaw; which, if not immediately corrected, could result in an uncontrollable maneuver and/or spin."

I guess the interviewee pilot on that show just confused everyone, well ok, maybe just me, with the statement “in the landing pattern”, which I assumed included the downwind and base legs.

tigisfat
September 9th, 2009, 07:21
Gee whiz.... I have flown a lot of different aircraft, including the Piper Warrior (My dad owned one). A standard rate of turn in a Warrior isn't much of a turn.Doesn't it take almost 20 degrees of bank at an average maneuvering speed in a 747 to get a 360 degree turn in 2 minutes?




My mechanic does an annual on a beautiful Staggerwing every Spring. I can see no particular reason why such might be true. I wish I knew, I'm not a Staggerwing pilot. I've only heard and read this.



You are going to have to explaine to me (equations are fine) just why no compensatory AOA is needed to increase the CL when some of the lift component is diverted to the side to produce a turn, any turn. I did suffer through a lot of physics in under grad and grad schoolI never attended grad school, I only know my experience with Warriors. I flew them for instrument, commercial and CFI; I'm much more of a Cessna guy. Sure, you're not going to accomplish a steep turn in a warrior without bringing the nose up to compensate for the loss of lift, but at standard rate the down wing makes more lift; in fact enough lift to compensate for the loss of lift on the up wing.

fliger747
September 9th, 2009, 09:42
Urban myth..... Unless some slop in the stabilator is doing something wierd....

Yea, I like Cessna's too, never too fond of the Piper stabalator system feel wise. I always thought the 182 and 185 were about my favorites. Just don't let someone put 900# of beer in one unless you want to find out about negative pitch stability. Though the Supercub is a lighter aircraft, and has a stick (which I like a lot) the control forces are heavier!

True enough that Supersonic thin wings have different handeling charchteristics. Leading edge flaps have helped the high AOA handeling a lot in modern versions, as has the energizing vortex that rolls off the strakes such as in the FA18. The Concorde also depends on a similar vortex to energize the upper surface and reduce the tendency to have flow seperation.

Unfortunatly I don't know anyone who admits to being a Hun driver, though I do know F-4's, F-8's, A6's, A-4's AD's, Vigilante's, F-18's, F-15's.... Trying to think, but I don't have any Tomcat driver that come to mind, though I know a bunch of pilots who are..... Tomcats.

The 747-400 wing is a marvel, but I can't wait to fly the 747-8 when it comes out (hopefully) next year. At Mach numbers around .90 we are into the transonic range and you can see the shockwaves standing up inboard of the winglets. I think that location may have some local acceleration due to the end span effect of the winglet. The dash-8 has a much more gently curved winglet.

My daughter is about to lurch off on aquisition of her instrument rating! That instruction field is where students learn a lot about precision flying!

Cheers: t.

fsafranek
September 9th, 2009, 11:52
Mr. Davies is now developing his F-100 for the RAZBAM label.

I get the impression from reading in another forum that that fell through.
:ernae:
Oops. My apologies for spreading some misinformation on Michael's F-100D.
http://www.throttleback.net/index.php?topic=1149.msg5900#msg5900
:ernae:

Bob.sc
September 9th, 2009, 13:53
Back to the F-100 Slow Speed characteristics...
Yes it is true, in the HUN, at speeds ? below 270kts your AOA increased and thus less Aileron and more Rudder was used. The known term for this is Adverse Yaw. The same Slow speed flight control was used in the F-4. I know that in the F-4, at VERY high AOA moving the stick left or right resulted in a harry departure of controlled flight.
Just study Adverse Yaw and you will gain more understanding.
Cheers,
Bob

PRB
September 9th, 2009, 15:23
...For those that are interested, I suggest "Aerodynamics for Naval Aviators", which includes my Marine compatriots... so it is generally written in English. ...
Ok, that's funny (sorry Mud!) :d



On adverse yaw. Did some “Googling”. Evidently the phenomenon is not limited to swept wing fighters of the 1960s. All airplanes experience it, as an effect of rolling, when the up wing, generating more lift, also produces more induced drag, than the down wing, which causes the nose to yaw in the direction of the up wing. But if you were using the rudder to coordinate your turn, wouldn’t the rudder input, “towards” the down wing, compensate for this? I’ve read that one method airplane designers use to eliminate adverse yaw is to couple the rudder to the aileron, a feature that was built into the Wright Flyer, for this very reason!
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I’m wondering why the effect would be worse at high AOA. Perhaps because at high AOA, the aileron pushing the wing up is at more or a right angle to the wind than it would be at low AOA, which would create more of a drag offset?

jmig
September 9th, 2009, 18:53
Ok, that's funny (sorry Mud!) :d



On adverse yaw. Did some “Googling”. Evidently the phenomenon is not limited to swept wing fighters of the 1960s. All airplanes experience it, as an effect of rolling, when the up wing, generating more lift, also produces more induced drag, than the down wing, which causes the nose to yaw in the direction of the up wing. But if you were using the rudder to coordinate your turn, wouldn’t the rudder input, “towards” the down wing, compensate for this? I’ve read that one method airplane designers use to eliminate adverse yaw is to couple the rudder to the aileron, a feature that was built into the Wright Flyer, for this very reason!
<o:p></o:p>
I’m wondering why the effect would be worse at high AOA. Perhaps because at high AOA, the aileron pushing the wing up is at more or a right angle to the wind than it would be at low AOA, which would create more of a drag offset?

OK Paul, let me see if I can remember correctly. At very high AOA the wing is basically stalled. If I remember correctly, the wing stalls from the fuselage outward. So only the wing tips are holding the airplane up. Now, introduce additional drag by moving the aileron up into the wind and you can imagine what happens.

Modern fighters, i.e., F-16, F-18 have automatic flaps, leading and trailing edge that will deploy in high AOA conditions to provide better performance. that is why the Blue Angels and Thunderbirds can come by at 130 kts with the nose so high. That and ample excess thrust :)

tigisfat
September 9th, 2009, 21:23
Urban myth...

No sir, I can personally vouch for this. It's not a myth. I do it in warriors all the time when doing shallow turns.

What country are you from, if you don't mind my asking?

fliger747
September 9th, 2009, 22:48
Alaska.... The only thing I can figure is that the slight AOA increase might cause a slight blanketing of the Stabilator form the propwash which would decrease the downforce on the tail. At low AOA, bank conditions, extranious factors can creep in. Certainly the lift geometry of the wings does not support such a contention. The second law of thermodynamics creeps in.... A certian amount of energy is required to produce the lift, and a certain amount of energy to produce the turn. If the turn remains level, either power must be added or airspeed will decrease, reaquiring an increased AOA... an on and on.

The first law is summarized as: "ya can't get somth'n for nutt'n".

The second law is: "Ya cann'a break even"....

Still hold pretty true outside of fusion....

Do a vector anaylis on the two wings at any desired bank angle and you will see that they combine to make the combined lift vector acting through the center of lift. Taking the ultimate dihedral of 45 deg... an interesting case applies as the rudder comes in to add some AOA to the down wing to maintain altitude as the up wing provides a turning lift.... All points to the increased energy requirements in a turn to maintain level undeccelerated flight.

In the 747-400 I add about 2 knobs of thrust in a level steep turn (we do those like everyone else). Our wings are flexible and dihedral varieds with fuel loading, so ya never know what ya got exactly.... Adding any thrust? Next trime you go out put on your test pilot hat and figure out what exactly is happening. Something is going on that does not violate the free lunch theorum. I am curious.

Best wishes: t

tigisfat
September 9th, 2009, 23:22
Sure, but the dihedral/anhedral accounts for losses and gains of lift as well, not just AOA. Imagine with me two wings with the same wing area, AOA and dihedral that produce drastically different lift at drastically different speeds. What's the answer? Please humor me.


A certian amount of energy is required to produce the lift, and a certain amount of energy to produce the turn.You're joking, right? The second law of thermodynamics is summed up most commonly as: "the entropy of the universe tends to a maximum" and refers to work obtained from non-equilibrium differences by a heat engine. Going further, you can break even. Opposite forces tend to equalize. You're talking about lift and turning tendencies as if they're something different. Are you just messing with me? You are a 747 pilot, right?

The horizontal component of lift turns an aircraft, bar none. The amount of vertical lift lost when it turns horizontal determines the amount (if at all) of vertical lift needed. This lift can be obtained many ways, not just through increases in backpressure and all that backpressure encompasses.


We also never spoke of increased thrust, we only spoke of a requirement or lack thereof backpressure.

jmig
September 10th, 2009, 04:08
Sure, but the dihedral/anhedral accounts for losses and gains of lift as well, not just AOA. Imagine with me two wings with the same wing area, AOA and dihedral that produce drastically different lift at drastically different speeds. What's the answer? Please humor me.

You're joking, right? The second law of thermodynamics is summed up most commonly as: "the entropy of the universe tends to a maximum" and refers to work obtained from non-equilibrium differences by a heat engine. Going further, you can break even. Opposite forces tend to equalize. You're talking about lift and turning tendencies as if they're something different. Are you just messing with me? You are a 747 pilot, right?

The horizontal component of lift turns an aircraft, bar none. The amount of vertical lift lost when it turns horizontal determines the amount (if at all) of vertical lift needed. This lift can be obtained many ways, not just through increases in backpressure and all that backpressure encompasses.


We also never spoke of increased thrust, we only spoke of a requirement or lack thereof backpressure.

Actually, he is not joking. The 2nd Law of Thermodynamics basically says that it takes an input of energy to keep the status quo. This applies to everything in the universe. So a house left to itself will eventually fall apart. A muscle not exercised will go soft, etc.

You can never break even. That would be perpetual motion in action. Perpetual motion is impossible because of the above law of physics and the universe.

Using the airplane example, turning causes induced drag. This drag will result in lower airspeed and by extension less lift. To evercome entropy a spot of power is added to maintain airspeed and level flight.

Also, I am sure you didn't mean anything by it but, a statement such as,"Are you just messing with me? You are a 747 pilot, right?" can be seen as insulting. I think it is obvious that both you and fliger747 have flying experience and aviation knowledge. Questioning another's competency will only lead to negative things.