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 |
|
#1
|
|||
|
|||
spins from coordinated flight
"Dudley Henriques" wrote in message ... 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 ... 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! My thought is that we're splitting hairs in this thread. If the airplane is in coordinated flight and stalls straight ahead (no wing drop), a spin can't happen. But on most aircraft, one wing will drop first even if the ball is centered. This wing drop creates a yaw, opening up the possibility for a spin. -- Dudley Henriques |
#2
|
|||
|
|||
spins from coordinated flight
"Kyle Boatright" wrote in message My thought is that we're splitting hairs in this thread. If the airplane is in coordinated flight and stalls straight ahead (no wing drop), a spin can't happen. But on most aircraft, one wing will drop first even if the ball is centered. This wing drop creates a yaw, opening up the possibility for a spin. But the links that Dan_Thomas sent me indicated that the airplane would not stall "straight ahead" if you were in a climbing turn. The outside wing has a higher AoA which diverges even further as it initially drops. It was intriging to me as our vacation strip demands a short field takeoff into a hedgerow of trees and you'd want to be mindful of this if you stumbled into a maximum performance evasive manuever thru errors in planning or execution. |
#3
|
|||
|
|||
spins from coordinated flight
Kyle Boatright wrote:
"Dudley Henriques" wrote in message ... 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 ... 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! My thought is that we're splitting hairs in this thread. If the airplane is in coordinated flight and stalls straight ahead (no wing drop), a spin can't happen. But on most aircraft, one wing will drop first even if the ball is centered. This wing drop creates a yaw, opening up the possibility for a spin. -- Dudley Henriques The wing drop at a 1g stall is on the roll axis not the yaw axis . You need rudder to induce the yaw rate at the stall necessary to cause entry into auto rotation. -- Dudley Henriques |
#4
|
|||
|
|||
spins from coordinated flight
99% of the pilots will never have the ball centered all the way to a stall
break, it might look good 1/4 of a second before the break, but most pilots stop actively flying when they start to feel the onset of the buffet. The skilled pilot never stops making control adjustments. I'll cite a comment made by a DPE after he had passed a student I sent him for the private pilot practical test... "That airplane is out of rig, everybody spins it doing accelerated stalls, but your student didn't." "Kyle Boatright" wrote in message . .. | My thought is that we're splitting hairs in this thread. If the airplane is in coordinated flight and stalls straight ahead (no wing drop), a spin can't happen. But on most aircraft, one wing will drop first even if the ball is centered. This wing drop creates a yaw, opening up the possibility for a spin. |
#5
|
|||
|
|||
spins from coordinated flight
Thanks for this, this is consistent with what I believe (however I would be
eager to be rebutted). Todd "Dudley Henriques" wrote in message 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! -- Dudley Henriques |
#6
|
|||
|
|||
spins from coordinated flight
Dudley Henriques wrote: Todd W. Deckard wrote: I return to the original question: if the ball is in the middle will it spin? 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! There is a possibility that a flip to the outside can occur in a low speed but large bank climbing turn, since the angle of attack of the outboard wing is greater than that of the inboard wing. Thus, in a left climbing turn of 30 degrees or maore bank, the right wing experiences a higher angle of attack, and will stall first if the airspeed drops low enough, and especially if an accelerated stall is induced. I have had this demonstrated tome in a C150. The result is dramatic. The craft flips to the right, as in a half snap roll, ends up upside down, and one is obliged to recover by certain mens. My instructor then practiced much back stick to get back to right side up, managing the zoom safely. It's a bit more of a thrill and happens quicker than a conventional spin. It can be done in both directions, plenty of altitude, please.... NOTE: If you analyze angles of attacks in urns, level, descending, climbing, using a spiral helical surface as reference, you will see that in turning descent, the inner wing experiences a greater angle of attack and will fall safely to the inside of the turn, but when climbing the oppsite wing stalls first. Te flip to upside down is a total surprise. Hence in climbing steeply out of a takeoff, the speed, turn rate and bank must all be carefully managed. Usually, the less the turn rate, the better, the ball must alwys be kept centered and the airspeed must be kept always at least 1.2 Vso or more. A further hint is that in a cross-wind condition, especially when higher level winds are of a changing direction (usually rotates to the right on ascent in the northern hemisphere), it is best to make the first turn into the wind; If you take off of RY270 and the surface wind is from 300, the wind at 200 feet AGL will be from 310 and that at 400 feet AGL will be at 320 degrees, and likely of a higher wind speed. A gradual right turn (10 degrees bank) will present you with increasing airspeed and a more rapid rate of climb; wery safe and very efficient. On descent to landing, opposite things happen. As you descend, the head wind speed diminshes, and in the northern heispere it shifts a bit to the left. Here in Ohio, if there is any significant surface wind, I usually keep about 10 knots extra on early final (if Vso is 60 kts, I carry 70 or 80 kts. When about a half mile from touchdown, I often see a 5 to 10 konot drop in airspeed with no action on my part. Crosswind components accordingly dimiish in speed and shift a bit to the left. A crab angle serves on the first part of final descent. If any significant crosswind remains below 200 feet, a shift into a side slip, where fuselage is aligned with the runway while the upwing wing is down is best for touchdown, often on one wheel for a moment. Angelo Campanella |
#7
|
|||
|
|||
spins from coordinated flight
Dudley Henriques wrote: Todd W. Deckard wrote: I return to the original question: if the ball is in the middle will it spin? 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! There is a possibility that a flip to the outside can occur in a low speed but large bank climbing turn, since the angle of attack of the outboard wing is greater than that of the inboard wing. Thus, in a left climbing turn of 30 degrees or maore bank, the right wing experiences a higher angle of attack, and will stall first if the airspeed drops low enough, and especially if an accelerated stall is induced. I have had this demonstrated tome in a C150. The result is dramatic. The craft flips to the right, as in a half snap roll, ends up upside down, and one is obliged to recover by certain mens. My instructor then practiced much back stick to get back to right side up, managing the zoom safely. It's a bit more of a thrill and happens quicker than a conventional spin. It can be done in both directions, plenty of altitude, please.... NOTE: If you analyze angles of attacks in urns, level, descending, climbing, using a spiral helical surface as reference, you will see that in turning descent, the inner wing experiences a greater angle of attack and will fall safely to the inside of the turn, but when climbing the oppsite wing stalls first. Te flip to upside down is a total surprise. Hence in climbing steeply out of a takeoff, the speed, turn rate and bank must all be carefully managed. Usually, the less the turn rate, the better, the ball must alwys be kept centered and the airspeed must be kept always at least 1.2 Vso or more. A further hint is that in a cross-wind condition, especially when higher level winds are of a changing direction (usually rotates to the right on ascent in the northern hemisphere), it is best to make the first turn into the wind; If you take off of RY270 and the surface wind is from 300, the wind at 200 feet AGL will be from 310 and that at 400 feet AGL will be at 320 degrees, and likely of a higher wind speed. A gradual right turn (10 degrees bank) will present you with increasing airspeed and a more rapid rate of climb; wery safe and very efficient. On descent to landing, opposite things happen. As you descend, the head wind speed diminshes, and in the northern heispere it shifts a bit to the left. Here in Ohio, if there is any significant surface wind, I usually keep about 10 knots extra on early final (if Vso is 60 kts, I carry 70 or 80 kts. When about a half mile from touchdown, I often see a 5 to 10 konot drop in airspeed with no action on my part. Crosswind components accordingly dimiish in speed and shift a bit to the left. A crab angle serves on the first part of final descent. If any significant crosswind remains below 200 feet, a shift into a side slip, where fuselage is aligned with the runway while the upwing wing is down is best for touchdown, often on one wheel for a moment. Angelo Campanella |
#8
|
|||
|
|||
spins from coordinated flight
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).
Ok, now I'm confused again. If "stall plus yaw" is all that's necessary, and all (normal) turns involve yaw, then why won't it spin? Do I have the wrong definition of "yaw"? Jose -- You can choose whom to befriend, but you cannot choose whom to love. for Email, make the obvious change in the address. |
#9
|
|||
|
|||
spins from coordinated flight
Jose wrote:
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). Ok, now I'm confused again. If "stall plus yaw" is all that's necessary, and all (normal) turns involve yaw, then why won't it spin? Do I have the wrong definition of "yaw"? Jose A "normal" turn is accomplished by splitting the lift vector, NOT by holding in yaw. Yaw should only be present in the turn dynamic during the entry into the turn and exit from the turn. Once stabilized in the turn, there should be no yaw present. There could be however if the turn was a slipping turn or a skidding turn. -- Dudley Henriques |
#10
|
|||
|
|||
spins from coordinated flight
Recently, Bertie the Bunyip posted:
BTW, stalls in a climbing turn are pretty much standard standard stuff even for Private pilots. Standard, and _required_ for the practical. I had to do both climbing and descending turning stalls for my checkride. Possibly because I chose to do my checkride in the middle of winter with an 18 kt. breeze and the examiner didn't want to die... ;-) Neil |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
spins from coordinated flight | Todd W. Deckard | Piloting | 61 | December 29th 07 01:28 AM |
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 |