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Stall Speeds Won't Save You - AoA Will


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Best angle of climb occurs at maximal S, which is at an angle and speed where thrust minus drag (thrust available) is maximised.

Yep.Simple pilot theory is far from true in real life. Neither speed for best angle of climb nor best rate of climb occur at a "fixed angle of attack"! Refer: http://cospilot.com/documents/Why%20Vx%20and%20Vy%20Change%20with%20Altitude.pdf

 

 

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Yep.Simple pilot theory is far from true in real life. Neither speed for best angle of climb nor best rate of climb occur at a "fixed angle of attack"! Refer: http://cospilot.com/documents/Why Vx and Vy Change with Altitude.pdf

Ah, I see where the misunderstanding between Ada and I is, I am talking angles, Ada is talking speed (ie. The thing I wanted to stop talking about).

In a glider, the max climb rate is naturally going to be the Max L/D which is a fixed AoA, this is also the case for any airfoil. In a powered aircraft it will be the Max L/D + thrust.

 

As a side note, don't forget the Lift Formula, make CL the subject and you'll be halfway there.

 

 

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In a glider, the max climb rate is naturally going to be the Max L/D which is a fixed AoA, this is also the case for any airfoil. In a powered aircraft it will be the Max L/D + thrust.

I don't think this is actually true.

 

Max L/D gives you best glide ratio, but doesn't give you lowest RoD. If you look at a typical glider polar, max L/D is the tangent to the polar; lowest RoD is the top of the polar.

 

 

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Watching training and other vids on youtube I am amazed by the amont of awfull flying. Every time you touch a control it creates drag. Even on a nice day some guys cannot stop pumping the pole. Final approach and hold off are even worse. No wonder an aircraft wants to stall and get revenge. Chas

 

 

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I realise from all this high falutin theory that I know absolutely nothing about flying. I wonder how I have survived for 47 years as a pilot without knowing my angle of attack. I do know that it appears awesome when I pull the stick hard back, with full throttle and go up. The wing appears to be at about 45 deg to the horizon and I still keep going up until the CHT gets too high.

I know how you feel, Yen. My education in things aeronautical leaves much to be desired too and now I even keep forgetting what I learned along the way...thank goodness my old Auster has had a bit of practice or I don't know what I'd do. 053_no.gif.1b075e917db98e3e6efb5417cfec8882.gif

 

Kaz

 

 

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Try this recovery method in a stall turn in a Pitts, you'll find yourself in an inverted spin 9 out of 10 times. You need to install the wings, which may require back stick.

I would never get caught with that one because I have no interest in flying a Pitts and if I did, my instructor would explain it to me.012_thumb_up.gif.cb3bc51429685855e5e23c55d661406e.gif

 

Alan.

 

ps As you say I would also need to 'install the wings' before I went flying in the first place.

 

 

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Try this recovery method in a stall turn in a Pitts, you'll find yourself in an inverted spin 9 out of 10 times. You need to install the wings, which may require back stick.

Huh? The top of a stall turn is flown at about zero angle of attack if you do it properly, as opposed to "air show style". In fact, you are as far away from a stall as it is possible to be, during the yaw at the top.

 

 

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Try this recovery method in a stall turn in a Pitts, you'll find yourself in an inverted spin 9 out of 10 times. You need to install the wings, which may require back stick.

Huh? The top of a stall turn is flown at about zero angle of attack if you do it properly, as opposed to "air show style". In fact, you are as far away from a stall as it is possible to be, during the yaw at the top.

 

 

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Huh? The top of a stall turn is flown at about zero angle of attack if you do it properly, as opposed to "air show style". In fact, you are as far away from a stall as it is possible to be, during the yaw at the top.

The Pitts, Yaks 50,52,55 all have a tendency to "fall on their back" due to gyroscopic effect as the aircraft yaws through 180 degrees from the up line to the down line. (ie to the left in the Pitts or right in the Yaks). They also tend to roll in the same direction as the yaw, so in a Pitts you'd have full left rudder, right aileron and forward stick. Once the aircraft starts to accelerate it now has the correct control inputs for an inverted spin entry, which often occurs early on in conversion training if these control inputs are held for too long. Pilots who aerobat aircraft like the Tiger, Chippy, C150/152, Citabria tend to be taught to reduce power as the nose of the aircraft approaches the horizon and therefore don't experience this. When I was instructing in the Pitts S2A / Yak 52 I spent a great deal of time training people in recovery from inverted spins entered from a stall turn, the entry often occurred unintentionally.

 

 

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Huh? The top of a stall turn is flown at about zero angle of attack if you do it properly, as opposed to "air show style". In fact, you are as far away from a stall as it is possible to be, during the yaw at the top.

The Pitts, Yaks 50,52,55 all have a tendency to "fall on their back" due to gyroscopic effect as the aircraft yaws through 180 degrees from the up line to the down line. (ie to the left in the Pitts or right in the Yaks). They also tend to roll in the same direction as the yaw, so in a Pitts you'd have full left rudder, right aileron and forward stick. Once the aircraft starts to accelerate it now has the correct control inputs for an inverted spin entry, which often occurs early on in conversion training if these control inputs are held for too long. Pilots who aerobat aircraft like the Tiger, Chippy, C150/152, Citabria tend to be taught to reduce power as the nose of the aircraft approaches the horizon and therefore don't experience this. When I was instructing in the Pitts S2A / Yak 52 I spent a great deal of time training people in recovery from inverted spins entered from a stall turn, the entry often occurred unintentionally.

 

 

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That would make you sit up and look. Looks like we need a nice geared radial where the prop goes the other way. I have never experienced any marked tendency to react to gyroscopic forces in the DH 82 or DHC-1, but I always reduced power before the nose was level with the horizon because it would make the manoeuver less compact (more speed) You are not in any way stalled but I guess if you misjudged it and got too slow the rudder wouldn't be very effective with power off. so you would be in strife then. The weather cocking of the rudder helps once you are horizontal and the nose just drops. Have you done any with power off? Nev

 

 

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That would make you sit up and look. Looks like we need a nice geared radial where the prop goes the other way. I have never experienced any marked tendency to react to gyroscopic forces in the DH 82 or DHC-1, but I always reduced power before the nose was level with the horizon because it would make the manoeuver less compact (more speed) You are not in any way stalled but I guess if you misjudged it and got too slow the rudder wouldn't be very effective with power off. so you would be in strife then. The weather cocking of the rudder helps once you are horizontal and the nose just drops. Have you done any with power off? Nev

 

 

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The nice big rudder in the Blanik was all that was needed to do "power-off" stall turns when I was gliding 30 years ago.

 

Actually, the Warrior 161 did it quite nicely to the left, too. Pat Schip caught me out when he suddenly pulled WHA into an almost vertical climb and announced "your aircraft!" I instinctively kicked the rudder hard over...

 

Later, he then showed me how I should have just applied power and flown it away without losing height. Silly me .

 

Kaz. 025_blush.gif.9304aaf8465a2b6ab5171f41c5565775.gif

 

 

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The nice big rudder in the Blanik was all that was needed to do "power-off" stall turns when I was gliding 30 years ago.

 

Actually, the Warrior 161 did it quite nicely to the left, too. Pat Schip caught me out when he suddenly pulled WHA into an almost vertical climb and announced "your aircraft!" I instinctively kicked the rudder hard over...

 

Later, he then showed me how I should have just applied power and flown it away without losing height. Silly me .

 

Kaz. 025_blush.gif.9304aaf8465a2b6ab5171f41c5565775.gif

 

 

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