If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#52
|
|||
|
|||
spins from coordinated flight
For my conclusion I am fixed in the stall + yaw = spin (where I was to start
with). I appreciate the references to the Transport Canada material as the tendency for the airplane to "go over the top" when snapping over from a climbing turn was a very needed reminder and I intend to experiment with it aggressively next year with the appropriate equipment and circumstances. At Mr. Henriques suggestion I solicited an explaination from Rich Stowell: He is the evangelist for the P-A-R-E recovery acronymn. Power (to idle) Ailerons (to neutral) Rudder (against the spin) Elevator (briskly forward to break the stall). I must say he drafted a very thoughtful response to me in a direct email. The only conclusion I can offer to this essay is to point to his web site, and his book(s): http://www.richstowell.com/ He articulately explained that the inclinometer is not a precise indication of coordinated flight and that some form of yaw is a necessary ingredient to the spin. With this I'll sign off, thanks for the responses. Todd Deckard |
#53
|
|||
|
|||
spins from coordinated flight
Bertie the Bunyip wrote:
Dudley Henriques wrote in : Todd W. Deckard wrote: I have a limited exposure to spins (I've demonstrated spins or received spin instruction in 5 different airplanes on six different occasions). I have a commercial certificate (although you wouldn't think so from my demonstration of a chandelle). Maybe I did have to demonstrate a power on stall while in a climbing 20 degree bank, once. As I recall, we survived it. I return to the original question: if the ball is in the middle will it spin? Becuase I believe snowmobile suits are for snowmobiling and not for flying I won't have a chance to explore it with an aerobatic instructor and an appropriate (but drafty) airplane for a few months -- so I thought I would put the question in a bottle and throw it in the ocean. Regards Todd "Bertie the Bunyip" wrote in message news:f2aea120-c3c7-497c-bf68- ... On Dec 27, 1:42 pm, "Todd W. Deckard" wrote: Can you depart and spin from coordinated flight? Specifically a coordinated climbing turn? And courting disaster doing a chandelle? If you're going to do a commercial ticket you should be familair with spins intimately. An incipient spin shouldn't even make you break a sweat. The answer to the ball question is no. It won't spin. A ball centered airplane in a climbing turn is compensated by rudder and is considered coordinated (in the classic sense). If you introduce a climbing turn stall with the ball centered, you might get a temporary wing drop at the break but unless you introduce a yaw rate as the stall breaks; no yaw rate...no spin! Hm, yeah. I'l have to explore this abit when I get a chance. I was fond of allowing the aiplane to snap over the top and allowing it to enter a spin in thei scenario to demonstrate to students how easy it was to enter a spin from a departure stall. Having said that, it always required unco-ordinated flight, no matter how slight. Lesson was to keep your eye on the airplane and not sit there FDH. Bertie This is normal and many instructors (including myself BTW) use the climbing turn power on stall as an intro to spin entry as a demonstration (after careful verbal preparation with the student). What screws everybody up when dealing with whether the airplane will spin out of this cfg are the variables that are taking place as the airspeed dissipates just before the stall break. I personally don't like relying on the ball as the prime reference for yaw cancellation when entering this regime just before the stall. Between the slipstream forces and engine torque, the ball can be used as a general indicator for correction but is seldom dead on as an indicator that all yaw has been canceled out. The rub is that ther's a chance of discrepency between a centered ball and a true canceling of all yaw from the vertical axis of the airplane. Like most aerobatic instructors, I like visual cues in these situations and teach them constantly even to primary students. The wingtip is a great visual cue as you approach stall. If you stabilize the low wingtip tip visually against the ground then watch the left tip carefully, when the yaw has been compensated for by the correct amount of opposing rudder, that low tip will remain stable. If more rudder is needed, the tip will appear to move back on you. Stabilize that low wingtip and the stall break will be center nose down with little wing drop and little tendency to spin (no yaw...no spin). It's yaw if present, coupled with the other variables present in an uncoordinated cfg as the stall breaks that can cause that severe wing drop. This coupled with SUSTAINED UNCORRECTED YAW is what will produce a pro spin scenario. What confuses people the most about the stall break explanation as relates to wing drop is that even with yaw compensated for, there is still an AOA difference between the wings and possible interference with the high wing at the stall break. This is what causes that over the top scenario so familiar to everyone. There is as well the possibility of a low wing breaking stall under certain conditions of control misuse as the stall is breaking, but over the top is usually what happens. -- Dudley Henriques |
#54
|
|||
|
|||
spins from coordinated flight
Dudley Henriques wrote:
Bertie the Bunyip wrote: Dudley Henriques wrote in : Todd W. Deckard wrote: I have a limited exposure to spins (I've demonstrated spins or received spin instruction in 5 different airplanes on six different occasions). I have a commercial certificate (although you wouldn't think so from my demonstration of a chandelle). Maybe I did have to demonstrate a power on stall while in a climbing 20 degree bank, once. As I recall, we survived it. I return to the original question: if the ball is in the middle will it spin? Becuase I believe snowmobile suits are for snowmobiling and not for flying I won't have a chance to explore it with an aerobatic instructor and an appropriate (but drafty) airplane for a few months -- so I thought I would put the question in a bottle and throw it in the ocean. Regards Todd "Bertie the Bunyip" wrote in message news:f2aea120-c3c7-497c-bf68- ... On Dec 27, 1:42 pm, "Todd W. Deckard" wrote: Can you depart and spin from coordinated flight? Specifically a coordinated climbing turn? And courting disaster doing a chandelle? If you're going to do a commercial ticket you should be familair with spins intimately. An incipient spin shouldn't even make you break a sweat. The answer to the ball question is no. It won't spin. A ball centered airplane in a climbing turn is compensated by rudder and is considered coordinated (in the classic sense). If you introduce a climbing turn stall with the ball centered, you might get a temporary wing drop at the break but unless you introduce a yaw rate as the stall breaks; no yaw rate...no spin! Hm, yeah. I'l have to explore this abit when I get a chance. I was fond of allowing the aiplane to snap over the top and allowing it to enter a spin in thei scenario to demonstrate to students how easy it was to enter a spin from a departure stall. Having said that, it always required unco-ordinated flight, no matter how slight. Lesson was to keep your eye on the airplane and not sit there FDH. Bertie This is normal and many instructors (including myself BTW) use the climbing turn power on stall as an intro to spin entry as a demonstration (after careful verbal preparation with the student). What screws everybody up when dealing with whether the airplane will spin out of this cfg are the variables that are taking place as the airspeed dissipates just before the stall break. I personally don't like relying on the ball as the prime reference for yaw cancellation when entering this regime just before the stall. Between the slipstream forces and engine torque, the ball can be used as a general indicator for correction but is seldom dead on as an indicator that all yaw has been canceled out. The rub is that ther's a chance of discrepency between a centered ball and a true canceling of all yaw from the vertical axis of the airplane. Like most aerobatic instructors, I like visual cues in these situations and teach them constantly even to primary students. The wingtip is a great visual cue as you approach stall. If you stabilize the low wingtip tip visually against the ground then watch the left tip carefully, when the yaw has been compensated for by the correct amount of opposing rudder, that low tip will remain stable. If more rudder is needed, the tip will appear to move back on you. Stabilize that low wingtip and the stall break will be center nose down with little wing drop and little tendency to spin (no yaw...no spin). It's yaw if present, coupled with the other variables present in an uncoordinated cfg as the stall breaks that can cause that severe wing drop. This coupled with SUSTAINED UNCORRECTED YAW is what will produce a pro spin scenario. What confuses people the most about the stall break explanation as relates to wing drop is that even with yaw compensated for, there is still an AOA difference between the wings and possible interference with the high wing at the stall break. This is what causes that over the top scenario so familiar to everyone. There is as well the possibility of a low wing breaking stall under certain conditions of control misuse as the stall is breaking, but over the top is usually what happens. ...should read "watch the LOW tip carefully. I was mentally doing a left climbing turn stall and wrote left instead of low :-)) -- Dudley Henriques |
#55
|
|||
|
|||
spins from coordinated flight
Dudley Henriques wrote in
:= This is normal and many instructors (including myself BTW) use the climbing turn power on stall as an intro to spin entry as a demonstration (after careful verbal preparation with the student). What screws everybody up when dealing with whether the airplane will spin out of this cfg are the variables that are taking place as the airspeed dissipates just before the stall break. I personally don't like relying on the ball as the prime reference for yaw cancellation when entering this regime just before the stall. Between the slipstream forces and engine torque, the ball can be used as a general indicator for correction but is seldom dead on as an indicator that all yaw has been canceled out. The rub is that ther's a chance of discrepency between a centered ball and a true canceling of all yaw from the vertical axis of the airplane. Yeah, OK, I'd go along wiht this. Like most aerobatic instructors, I like visual cues in these situations and teach them constantly even to primary students. The wingtip is a great visual cue as you approach stall. If you stabilize the low wingtip tip visually against the ground then watch the left tip carefully, when the yaw has been compensated for by the correct amount of opposing rudder, that low tip will remain stable. If more rudder is needed, the tip will appear to move back on you. Stabilize that low wingtip and the stall break will be center nose down with little wing drop and little tendency to spin (no yaw...no spin). It's yaw if present, coupled with the other variables present in an uncoordinated cfg as the stall breaks that can cause that severe wing drop. This coupled with SUSTAINED UNCORRECTED YAW is what will produce a pro spin scenario. What confuses people the most about the stall break explanation as relates to wing drop is that even with yaw compensated for, there is still an AOA difference between the wings and possible interference with the high wing at the stall break. This is what causes that over the top scenario so familiar to everyone. There is as well the possibility of a low wing breaking stall under certain conditions of control misuse as the stall is breaking, but over the top is usually what happens. Yeah, OK. jibes with my experince ( I think, been a while). NEver thought of looking at the tip during it. I'll try it and let you know how I get on! Bertie |
#56
|
|||
|
|||
spins from coordinated flight
Bertie the Bunyip wrote:
Dudley Henriques wrote in := This is normal and many instructors (including myself BTW) use the climbing turn power on stall as an intro to spin entry as a demonstration (after careful verbal preparation with the student). What screws everybody up when dealing with whether the airplane will spin out of this cfg are the variables that are taking place as the airspeed dissipates just before the stall break. I personally don't like relying on the ball as the prime reference for yaw cancellation when entering this regime just before the stall. Between the slipstream forces and engine torque, the ball can be used as a general indicator for correction but is seldom dead on as an indicator that all yaw has been canceled out. The rub is that ther's a chance of discrepency between a centered ball and a true canceling of all yaw from the vertical axis of the airplane. Yeah, OK, I'd go along wiht this. Like most aerobatic instructors, I like visual cues in these situations and teach them constantly even to primary students. The wingtip is a great visual cue as you approach stall. If you stabilize the low wingtip tip visually against the ground then watch the left tip carefully, when the yaw has been compensated for by the correct amount of opposing rudder, that low tip will remain stable. If more rudder is needed, the tip will appear to move back on you. Stabilize that low wingtip and the stall break will be center nose down with little wing drop and little tendency to spin (no yaw...no spin). It's yaw if present, coupled with the other variables present in an uncoordinated cfg as the stall breaks that can cause that severe wing drop. This coupled with SUSTAINED UNCORRECTED YAW is what will produce a pro spin scenario. What confuses people the most about the stall break explanation as relates to wing drop is that even with yaw compensated for, there is still an AOA difference between the wings and possible interference with the high wing at the stall break. This is what causes that over the top scenario so familiar to everyone. There is as well the possibility of a low wing breaking stall under certain conditions of control misuse as the stall is breaking, but over the top is usually what happens. Yeah, OK. jibes with my experince ( I think, been a while). NEver thought of looking at the tip during it. I'll try it and let you know how I get on! Bertie Works like a charm in the vertical plane as well...loops....Cubans...etc. -- Dudley Henriques |
#57
|
|||
|
|||
spins from coordinated flight
Dudley Henriques wrote in news:9-qdnZO8Tvdst-
: Yeah, OK. jibes with my experince ( I think, been a while). NEver thought of looking at the tip during it. I'll try it and let you know how I get on! Bertie Works like a charm in the vertical plane as well...loops....Cubans...etc. Well, for that, obviously! I always had problems with reverse cubans though. I never did figure out a way to track my rotation perfecly going up. So, I just avoidd them! Bertie |
#58
|
|||
|
|||
spins from coordinated flight
Bertie the Bunyip wrote:
Dudley Henriques wrote in news:9-qdnZO8Tvdst- : Yeah, OK. jibes with my experince ( I think, been a while). NEver thought of looking at the tip during it. I'll try it and let you know how I get on! Bertie Works like a charm in the vertical plane as well...loops....Cubans...etc. Well, for that, obviously! I always had problems with reverse cubans though. I never did figure out a way to track my rotation perfecly going up. So, I just avoidd them! Bertie A Reverse Cuban or more correctly a 1/2 Reverse Cuban since the complete maneuver is simply two maneuvers done back to back put together :-) is in my opinion one of the hardest maneuvers for a novice to get right. First of all, it requires a high entry speed. For this reason, and as well the slow roll rate of the Citabria and other flat wing light aerobatic trainers, doing a good 1/2 reverse Cuban is not the easiest thing to accomplish. You can do one, but it amounts to a sloppy 1/2 roll at the top followed almost immediately by a Split S. It isn't pretty in these airplanes. To do a 1/2 Reverse Cuban correctly, you need an established 45 degree up line erect, a quick 1/2 slow roll and an inverted 45 degree up line continued as the energy drops down to the 1/2 inside Loop recovery. The timing is critical as is the airspeed at the top gate as the pull is initiated. In an underpowered airplane restricted by a low never exceed speed you are severely hampered in obtaining the energy required to do the maneuver properly. As for visuals; you use the wing tips for establishing BOTH up lines right side up and inverted, but in a Citabria or an Aerobat for example, the low entry speed coupled with the energy lost doing the roll to inverted leave you with little time to even establish an inverted 45 degree up line :-) The result is sort of like doing what I refer to as a 1/2 whale roll and a pull down into a 1/2 loop recovery. You can get a decent 1/2 Reverse Cuban out of a Decathlon but barely :-) Now the Extra, or a Pitts is another matter entirely :-)) But don't feel bad about not getting this one down just right. Actually if you DID get one right within the airspeed and g limits suggested for the Citabria or Aerobat type airplane you happened to be flying, you'd be doing quite well :-) -- Dudley Henriques |
#59
|
|||
|
|||
spins from coordinated flight
Dudley Henriques wrote in
: Bertie the Bunyip wrote: Dudley Henriques wrote in news:9-qdnZO8Tvdst- : Yeah, OK. jibes with my experince ( I think, been a while). NEver thought of looking at the tip during it. I'll try it and let you know how I get on! Bertie Works like a charm in the vertical plane as well...loops....Cubans...etc. Well, for that, obviously! I always had problems with reverse cubans though. I never did figure out a way to track my rotation perfecly going up. So, I just avoidd them! Bertie A Reverse Cuban or more correctly a 1/2 Reverse Cuban since the complete maneuver is simply two maneuvers done back to back put together :-) is in my opinion one of the hardest maneuvers for a novice to get right. First of all, it requires a high entry speed. For this reason, and as well the slow roll rate of the Citabria and other flat wing light aerobatic trainers, doing a good 1/2 reverse Cuban is not the easiest thing to accomplish. You can do one, but it amounts to a sloppy 1/2 roll at the top followed almost immediately by a Split S. It isn't pretty in these airplanes. To do a 1/2 Reverse Cuban correctly, you need an established 45 degree up line erect, a quick 1/2 slow roll and an inverted 45 degree up line continued as the energy drops down to the 1/2 inside Loop recovery. The timing is critical as is the airspeed at the top gate as the pull is initiated. In an underpowered airplane restricted by a low never exceed speed you are severely hampered in obtaining the energy required to do the maneuver properly. As for visuals; you use the wing tips for establishing BOTH up lines right side up and inverted, but in a Citabria or an Aerobat for example, the low entry speed coupled with the energy lost doing the roll to inverted leave you with little time to even establish an inverted 45 degree up line :-) The result is sort of like doing what I refer to as a 1/2 whale roll and a pull down into a 1/2 loop recovery. You can get a decent 1/2 Reverse Cuban out of a Decathlon but barely :-) Now the Extra, or a Pitts is another matter entirely :-)) But don't feel bad about not getting this one down just right. Actually if you DID get one right within the airspeed and g limits suggested for the Citabria or Aerobat type airplane you happened to be flying, you'd be doing quite well :-) I used to od them in the Decathlon and they were OK ish, but certainly not up to competition standards. It was the lack of decent reference, really, not so much the performance or the agility of the airplane. Going vertical was OK since the wingtip would stay at the same place on the way up, but on a 45 I had nothing I could ever get a bead on to maintain the line. They were OK. I didn't end up 90 deg to m entry heading or anything, just not all that tidy. It'll be interesting to see if I can do any better second time around! Bertie |
#60
|
|||
|
|||
spins from coordinated flight
Bertie the Bunyip wrote:
Dudley Henriques wrote in : Bertie the Bunyip wrote: Dudley Henriques wrote in news:9-qdnZO8Tvdst- : Yeah, OK. jibes with my experince ( I think, been a while). NEver thought of looking at the tip during it. I'll try it and let you know how I get on! Bertie Works like a charm in the vertical plane as well...loops....Cubans...etc. Well, for that, obviously! I always had problems with reverse cubans though. I never did figure out a way to track my rotation perfecly going up. So, I just avoidd them! Bertie A Reverse Cuban or more correctly a 1/2 Reverse Cuban since the complete maneuver is simply two maneuvers done back to back put together :-) is in my opinion one of the hardest maneuvers for a novice to get right. First of all, it requires a high entry speed. For this reason, and as well the slow roll rate of the Citabria and other flat wing light aerobatic trainers, doing a good 1/2 reverse Cuban is not the easiest thing to accomplish. You can do one, but it amounts to a sloppy 1/2 roll at the top followed almost immediately by a Split S. It isn't pretty in these airplanes. To do a 1/2 Reverse Cuban correctly, you need an established 45 degree up line erect, a quick 1/2 slow roll and an inverted 45 degree up line continued as the energy drops down to the 1/2 inside Loop recovery. The timing is critical as is the airspeed at the top gate as the pull is initiated. In an underpowered airplane restricted by a low never exceed speed you are severely hampered in obtaining the energy required to do the maneuver properly. As for visuals; you use the wing tips for establishing BOTH up lines right side up and inverted, but in a Citabria or an Aerobat for example, the low entry speed coupled with the energy lost doing the roll to inverted leave you with little time to even establish an inverted 45 degree up line :-) The result is sort of like doing what I refer to as a 1/2 whale roll and a pull down into a 1/2 loop recovery. You can get a decent 1/2 Reverse Cuban out of a Decathlon but barely :-) Now the Extra, or a Pitts is another matter entirely :-)) But don't feel bad about not getting this one down just right. Actually if you DID get one right within the airspeed and g limits suggested for the Citabria or Aerobat type airplane you happened to be flying, you'd be doing quite well :-) I used to od them in the Decathlon and they were OK ish, but certainly not up to competition standards. It was the lack of decent reference, really, not so much the performance or the agility of the airplane. Going vertical was OK since the wingtip would stay at the same place on the way up, but on a 45 I had nothing I could ever get a bead on to maintain the line. They were OK. I didn't end up 90 deg to m entry heading or anything, just not all that tidy. It'll be interesting to see if I can do any better second time around! Bertie I'm sure you will. Generally for practice anyway, you can pick a long road or anything straight in front of you extending a bit into the distance. Do the roll as a slow roll but do it fast. The visuals are easy really in this scenario. Use the left tip and form a 45 with about a 4g pull and set to the angle formed by the wing and the horizon. It isn't nearly as accurate as a metal or FG tip cross attachment but close enough for government work. Do the roll quickly holding in some excessive forward pressure past knife and on into inverted. The Citabria will have a seemingly VERY high inverted nose attitude at the inverted 45 due to the flat wing and angle of attack needed to keep the airplane stable on the 45 inverted up line. As you go past knife edge switch the visual cue directly over the nose and pick up the extended reference and adjust if needed for the vertical maneuver line. Check the wingtip for the inverted 45 up line but be aware that in the Citabria you probably won't have any excess inverted up line time available before you relax the forward pressure and go through the float at the top. You should be just above stall so don't pull down, just relax the forward pressure and let the airplane float on through, then gently pull down as the airspeed starts to increase. Use about a 4g maximum radial g pull on the back side. When you can do this one well in the Citabria, you get the Gold Star for being able to fudge a 1/2 Reverse Cuban and make it look good in a Citabria :-)) -- Dudley Henriques |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Coordinated turns without rudder, and autopilots | Mxsmanic | Piloting | 188 | June 1st 07 07:09 PM |
Coordinated turns and the little ball | Mxsmanic | Piloting | 51 | October 11th 06 10:17 PM |
Is rudder required for coordinated turns? | Mxsmanic | Piloting | 41 | September 24th 06 06:40 PM |
Snap / Flick and spins in flight simulators | [email protected] | Simulators | 1 | September 2nd 06 07:10 AM |
Coordinated turning stall and spins | Chris OCallaghan | Soaring | 20 | November 18th 03 08:46 PM |