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#1
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Bob -
Yes, I misquoted the soft-field procedure, i'm sorry (I don't have the book in front of me). Could you elaborate more on your 'no' for the procedure I mentioned? I'm more interested in why one particular talkoff procedure over another... This is about increasing my personal understanding more than it is about simply being told 'what the book says' so to speak. Brian- Thanks for your input, some quick responses- True, But not a very smooth takeoff as you have pitch up, pitch down and then pitch back up. Done 'correctly' (again, I'm not 100% sure I'm correct, but the old timers at my club swear by it), the pitch down after attaining ground effect is very subtle... I do have to say that it "feels" really smooth. False in most cases on a paved runway, In fact I watched a Commache Crash doing this. Fully loaded he was off the ground in 1500 feet in ground affect nose high. He flew off the end of the 5000 foot runway still nose high and only 4 feet off the ground before he aborted the take off. He never was able to reach his best climb speed in the nose high, high drag configuration. Hmm... that's interesting, my initial sophomoric instinct suggests that perhaps he didn't release enough of the back-pressure to accelerate enough... but as I said - purely sophomoric judgement there. True, But good crosswind rudder and aileron control input will usually let you take off without having to do so. (Raise the downwind wing and keep straight with the rudder) A slip is still a slip though, isn't it? even if you're correctly downwind-wing-high and on your upwind gear, the wind is still striking the fuselage at an angle. False, See response to #2 DA was a significant factor in that accident, But if proper short field technique had been used I believe they would not have had an issue. I have no experience with higher DA yet, so I am completely un-qualified to comment I suppose - I am merely quoting what i have been told ![]() Did you mean Soft Field? yes |
#2
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![]() Could you elaborate more on your 'no' for the procedure I mentioned? I'm more interested in why one particular talkoff procedure over another... This is about increasing my personal understanding more than it is about simply being told 'what the book says' so to speak. Sure, True, But not a very smooth takeoff as you have pitch up, pitch down and then pitch back up. Done 'correctly' (again, I'm not 100% sure I'm correct, but the old timers at my club swear by it), the pitch down after attaining ground effect is very subtle... I do have to say that it "feels" really smooth. It can be done very smoothly but this is normally done by not lifting off at minimum airspeed (full up elevator) but rather just raising the nose to about the normal climb attitude. Doing this the aircraft will lift off at a lower than normal climb speed float in the ground affect until reaching the normal climb speed and then climb out. You will have to adjust the elevator as the aircraft accelerates but the attitude will not change. I often teach this to new students because it is simple and works really well and you don't have to look at the ASI at all to do so. Just let the airplane accelerate until you just before you think it is ready to fly, Pull back to raise the nose of the aircraft until the top of the spinner is just below the Horizon (will vary some with different aircraft and pilots) and hold it there. You can try this by starting out with full elevator and as soon a the attitude reaches your nomal climb attitude hold it there. This is often done on gravel runways to raise the propeller as high off the ground as possible. This disadvantage to this technique is that the high angle of attack while still on the ground extends the ground run due to the extra drag caused by the high angle of attack. False in most cases on a paved runway, In fact I watched a Commache Crash doing this. Fully loaded he was off the ground in 1500 feet in ground affect nose high. He flew off the end of the 5000 foot runway still nose high and only 4 feet off the ground before he aborted the take off. He never was able to reach his best climb speed in the nose high, high drag configuration. Hmm... that's interesting, my initial sophomoric instinct suggests that perhaps he didn't release enough of the back-pressure to accelerate enough... but as I said - purely sophomoric judgement there. The biggest issue he had was he was using a modified soft feild technique when he should have been using a short field technique due to the high DA and Gross weight. I suspect he always took off this way and in a 250HP high performance aircraft it didn't occur to him that he should have been using a short feild. It did not occur to him to lower the nose because doing so in this situation would have caused him to settle back onto the runway. True, But good crosswind rudder and aileron control input will usually let you take off without having to do so. (Raise the downwind wing and keep straight with the rudder) A slip is still a slip though, isn't it? even if you're correctly downwind-wing-high and on your upwind gear, the wind is still striking the fuselage at an angle. Yes it is a slip, but having a little extra speed after lift off will prevent you from settling back on the runway and it is better to be aligned with the runway if you do settle back onto the runway. Once a positive rate of climb is established then release the rudder pressure to a normal climb setting and let the aircraft Crab into the wind for maximum climb rate or angle. ----- Perhaps I didn't respond correctly to your 1st post. It just got my attention because I have seen an accident caused by this technique. But the accident was probably caused more by the fact that this was not the technique to use in that situation. You were asking more about Normal Take off's and landing. The technique your instructor recommends will work just fine for normal takes-offs. Here are my points on it remembering these are normal takes offs. 1 Plus, Helps protect the Prop from Debris. 2. Minus, Longer take off roll due to high angle of attack while stilling rolling 3. Minus, Slight less control lifting off at minimum flying speed, some chance of settling back onto runway. 4, Slight Plus, Less wear and tear on tires and struts (minimual difference in my opinion) Hope this helps Brian CFIIG/ASEL |
#3
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![]() Could you elaborate more on your 'no' for the procedure I mentioned? I'm more interested in why one particular talkoff procedure over another... This is about increasing my personal understanding more than it is about simply being told 'what the book says' so to speak. Sure, True, But not a very smooth takeoff as you have pitch up, pitch down and then pitch back up. Done 'correctly' (again, I'm not 100% sure I'm correct, but the old timers at my club swear by it), the pitch down after attaining ground effect is very subtle... I do have to say that it "feels" really smooth. It can be done very smoothly but this is normally done by not lifting off at minimum airspeed (full up elevator) but rather just raising the nose to about the normal climb attitude. Doing this the aircraft will lift off at a lower than normal climb speed float in the ground affect until reaching the normal climb speed and then climb out. You will have to adjust the elevator as the aircraft accelerates but the attitude will not change. I often teach this to new students because it is simple and works really well and you don't have to look at the ASI at all to do so. Just let the airplane accelerate until you just before you think it is ready to fly, Pull back to raise the nose of the aircraft until the top of the spinner is just below the Horizon (will vary some with different aircraft and pilots) and hold it there. You can try this by starting out with full elevator and as soon a the attitude reaches your nomal climb attitude hold it there. This is often done on gravel runways to raise the propeller as high off the ground as possible. This disadvantage to this technique is that the high angle of attack while still on the ground extends the ground run due to the extra drag caused by the high angle of attack. False in most cases on a paved runway, In fact I watched a Commache Crash doing this. Fully loaded he was off the ground in 1500 feet in ground affect nose high. He flew off the end of the 5000 foot runway still nose high and only 4 feet off the ground before he aborted the take off. He never was able to reach his best climb speed in the nose high, high drag configuration. Hmm... that's interesting, my initial sophomoric instinct suggests that perhaps he didn't release enough of the back-pressure to accelerate enough... but as I said - purely sophomoric judgement there. The biggest issue he had was he was using a modified soft feild technique when he should have been using a short field technique due to the high DA and Gross weight. I suspect he always took off this way and in a 250HP high performance aircraft it didn't occur to him that he should have been using a short feild. It did not occur to him to lower the nose because doing so in this situation would have caused him to settle back onto the runway. True, But good crosswind rudder and aileron control input will usually let you take off without having to do so. (Raise the downwind wing and keep straight with the rudder) A slip is still a slip though, isn't it? even if you're correctly downwind-wing-high and on your upwind gear, the wind is still striking the fuselage at an angle. Yes it is a slip, but having a little extra speed after lift off will prevent you from settling back on the runway and it is better to be aligned with the runway if you do settle back onto the runway. Once a positive rate of climb is established then release the rudder pressure to a normal climb setting and let the aircraft Crab into the wind for maximum climb rate or angle. ----- Perhaps I didn't respond correctly to your 1st post. It just got my attention because I have seen an accident caused by this technique. But the accident was probably caused more by the fact that this was not the technique to use in that situation. You were asking more about Normal Take off's and landing. The technique your instructor recommends will work just fine for normal takes-offs. Here are my points on it remembering these are normal takes offs. 1 Plus, Helps protect the Prop from Debris. 2. Minus, Longer take off roll due to high angle of attack while stilling rolling 3. Minus, Slight less control lifting off at minimum flying speed, some chance of settling back onto runway. 4, Slight Plus, Less wear and tear on tires and struts (minimual difference in my opinion) Hope this helps Brian CFIIG/ASEL |
#4
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![]() Could you elaborate more on your 'no' for the procedure I mentioned? I'm more interested in why one particular talkoff procedure over another... This is about increasing my personal understanding more than it is about simply being told 'what the book says' so to speak. Sure, True, But not a very smooth takeoff as you have pitch up, pitch down and then pitch back up. Done 'correctly' (again, I'm not 100% sure I'm correct, but the old timers at my club swear by it), the pitch down after attaining ground effect is very subtle... I do have to say that it "feels" really smooth. It can be done very smoothly but this is normally done by not lifting off at minimum airspeed (full up elevator) but rather just raising the nose to about the normal climb attitude. Doing this the aircraft will lift off at a lower than normal climb speed float in the ground affect until reaching the normal climb speed and then climb out. You will have to adjust the elevator as the aircraft accelerates but the attitude will not change. I often teach this to new students because it is simple and works really well and you don't have to look at the ASI at all to do so. Just let the airplane accelerate until you just before you think it is ready to fly, Pull back to raise the nose of the aircraft until the top of the spinner is just below the Horizon (will vary some with different aircraft and pilots) and hold it there. You can try this by starting out with full elevator and as soon a the attitude reaches your nomal climb attitude hold it there. This is often done on gravel runways to raise the propeller as high off the ground as possible. This disadvantage to this technique is that the high angle of attack while still on the ground extends the ground run due to the extra drag caused by the high angle of attack. False in most cases on a paved runway, In fact I watched a Commache Crash doing this. Fully loaded he was off the ground in 1500 feet in ground affect nose high. He flew off the end of the 5000 foot runway still nose high and only 4 feet off the ground before he aborted the take off. He never was able to reach his best climb speed in the nose high, high drag configuration. Hmm... that's interesting, my initial sophomoric instinct suggests that perhaps he didn't release enough of the back-pressure to accelerate enough... but as I said - purely sophomoric judgement there. The biggest issue he had was he was using a modified soft feild technique when he should have been using a short field technique due to the high DA and Gross weight. I suspect he always took off this way and in a 250HP high performance aircraft it didn't occur to him that he should have been using a short feild. It did not occur to him to lower the nose because doing so in this situation would have caused him to settle back onto the runway. True, But good crosswind rudder and aileron control input will usually let you take off without having to do so. (Raise the downwind wing and keep straight with the rudder) A slip is still a slip though, isn't it? even if you're correctly downwind-wing-high and on your upwind gear, the wind is still striking the fuselage at an angle. Yes it is a slip, but having a little extra speed after lift off will prevent you from settling back on the runway and it is better to be aligned with the runway if you do settle back onto the runway. Once a positive rate of climb is established then release the rudder pressure to a normal climb setting and let the aircraft Crab into the wind for maximum climb rate or angle. ----- Perhaps I didn't respond correctly to your 1st post. It just got my attention because I have seen an accident caused by this technique. But the accident was probably caused more by the fact that this was not the technique to use in that situation. You were asking more about Normal Take off's and landing. The technique your instructor recommends will work just fine for normal takes-offs. Here are my points on it remembering these are normal takes offs. 1 Plus, Helps protect the Prop from Debris. 2. Minus, Longer take off roll due to high angle of attack while stilling rolling 3. Minus, Slight less control lifting off at minimum flying speed, some chance of settling back onto runway. 4, Slight Plus, Less wear and tear on tires and struts (minimual difference in my opinion) Hope this helps Brian CFIIG/ASEL |
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