That's what I thought. Though impressive, the entire stab is not gone like with the airbusses. There is still just enough there to prevent catastrophe. Kudos to Boeing. Unless someone can show official proof otherwise, I still say the loss of the ENTIRE vertical stab will cause a crash, and I provided the NTSB link twice showing a very high profile example. I can't believe we're still debating this.
Unless you loose an engine or you tackle a cross wind landing, when do you use rudders??
In normal conditions (and re-trimming ) an airplane should fly just fine without that appendix.
The 380 is the one the other girls say has "beautiful eyes and great personality"
Man is THAT ever correct. I taxied past one the other day in Narita. It showed me why that airplane is never photographed directly from the side. It is one ugly airplane.
Yeah, but she can keep you up all night long, for whatever that's worth
Unless you loose an engine or you tackle a cross wind landing, when do you use rudders??
In normal conditions (and re-trimming ) an airplane should fly just fine without that appendix.
But you are using your vert stab the entire flight! By the way, I don't know what aircraft you fly, but if it has yaw dampers you are using the rudders the entire flight.
Even without a rudder, when the nose starts to yaw left or right the side of the aircraft starts to become exposed to the relative slipstream. The tendency of the aircraft to return to a non-yaw state depends on how much surface area behind the CG is exposed to the slipstream compared the area front. The bigger the difference, the stronger the natural tendency to return to a non-yaw state. Even if only a portion of the stab is remaining, such as the stab on the B-52 that is still a large amount of surface area, it is still increasing the difference between area forward and aft of the CG. Don't compare the remaining vert stab to the original vert-stab, the original vert stab was sized to provide yaw control in a worst-case engine failure, not to provide simple yaw control to a symmetric aircraft.
Since most aircraft have more fuselage side-area aft of the CG than forward, there is some natural tendency to return to neutral. However, it isn't a very strong tendency and small items such as the adverse yaw of aileron displacement can overcome that tendency. So you have a swept-wing aircraft lose its entire vert stab, it has a slight natural tendency to tend back to neutral; any aileron input will have a tendency to cause yaw, any yaw will cause a resultant roll into the yaw as the opposite wing (left yaw / right wing) starts to produce more lift than the other, the pilot is required to make a corresponding aileron input, the corresponding aileron input causes adverse yaw again, as the nose transits to neutral the lack of a strong tendency to neutral causes it to overshoot neutral, repeat. Even slight differential thrust due to increasing or decreasing power can cause the same chain of events. Add turbulence or any other complicating factor and the resultant PIO will likely lead to disaster. For those of you who acknowledge how strong the dutch-roll tendency is on some aircraft with a full vert-stab, imagine it with little or no vert-stab - the nose transients would be even greater.
But you are using your vert stab the entire flight! By the way, I don't know what aircraft you fly, but if it has yaw dampers you are using the rudders the entire flight.
Even without a rudder, when the nose starts to yaw left or right the side of the aircraft starts to become exposed to the relative slipstream. The tendency of the aircraft to return to a non-yaw state depends on how much surface area behind the CG is exposed to the slipstream compared the area front. The bigger the difference, the stronger the natural tendency to return to a non-yaw state. Even if only a portion of the stab is remaining, such as the stab on the B-52 that is still a large amount of surface area, it is still increasing the difference between area forward and aft of the CG. Don't compare the remaining vert stab to the original vert-stab, the original vert stab was sized to provide yaw control in a worst-case engine failure, not to provide simple yaw control to a symmetric aircraft.
Since most aircraft have more fuselage side-area aft of the CG than forward, there is some natural tendency to return to neutral. However, it isn't a very strong tendency and small items such as the adverse yaw of aileron displacement can overcome that tendency. So you have a swept-wing aircraft lose its entire vert stab, it has a slight natural tendency to tend back to neutral; any aileron input will have a tendency to cause yaw, any yaw will cause a resultant roll into the yaw as the opposite wing (left yaw / right wing) starts to produce more lift than the other, the pilot is required to make a corresponding aileron input, the corresponding aileron input causes adverse yaw again, as the nose transits to neutral the lack of a strong tendency to neutral causes it to overshoot neutral, repeat. Even slight differential thrust due to increasing or decreasing power can cause the same chain of events. Add turbulence or any other complicating factor and the resultant PIO will likely lead to disaster. For those of you who acknowledge how strong the dutch-roll tendency is on some aircraft with a full vert-stab, imagine it with little or no vert-stab - the nose transients would be even greater.
Agreed but I doubt that in he case of that b52 there was any use left for that portion of rudder.
The rest of your description fits the dc 10 "landing' in Sioux City.
However it seems that the new trend is to build aircrafts without what we call conventional rudder.
If I remember correctly, the B-52 crew lowered the aft gear for additional stability, delaying the fwd gear until set up on a long final. Of course, they also had chase planes, Boeing engineers on the line, and ejection seats!
There was a short AF film titled "Flight Without a Fin", if anyone can find it.
Agreed but I doubt that in he case of that b52 there was any use left for that portion of rudder.
I think I was pretty clear in describing how a vert stab without a rudder adds to yaw stability. Kind of like an arrow with fins is more stable than one without.
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