aro Posted September 2, 2017 Posted September 2, 2017 I would say that is very unlikely without banking the aircraft and changing the direction of the lift vector. 1
facthunter Posted September 2, 2017 Posted September 2, 2017 In a near vertical bank it does particularly, but is the concept helpful unless well qualified as to the particular circumstances? Tilting the lift vector from the wings provides the side force to make the plane deviate from a straight line. No lift no turn. To hold height and turn you need more lift, so the stick comes back a bit and you add power to stop the plane losing speed due extra drag associated with the extra lift. You may even need more power to maintain a safe airspeed margin OR you can descend to achieve the same airspeed situation if you are power limited or gliding. You can use the aircrafts keel surface and just turn flat with rudder alone if you are patient and like to be awkward and very different, same as you can fly on the fuselage alone with wings near vertical if the plane goes fast enough to get lift that way. None of this is "normal" ,but possible. If you are vertical UP or vertical DOWN you can also change direction by rolling, 180 degrees for course reversal in the extreme. Nev
djpacro Posted September 2, 2017 Posted September 2, 2017 I would say that is very unlikely without banking the aircraft and changing the direction of the lift vector. Put elevator to neutral and see if it turns while banked. 2
gandalph Posted September 2, 2017 Posted September 2, 2017 This thread seems to have drifted somewhat off topic into a more interesting and relevant area of discussion. Worth a separate thread in my opinion Can the Mods help with that?
facthunter Posted September 2, 2017 Posted September 2, 2017 It's only got value if people can put their mind in the particular situation and work out if it all makes sense at least. . It's a mind game not a flying instruction format, so recognise that fact and don't try it I reality, unless you have the right instructor /plane, plenty of height and have briefed it thoroughly.. Don't be afraid to question stuff. It can sort out some basic misconceptions, possibly. Nev
djpacro Posted September 2, 2017 Posted September 2, 2017 Perhaps start with the full description of how to turn from the FAA's Airplane Flying Handbook page 3-7: • The ailerons bank the wings and so determine the rate of turn at any given airspeed. • The elevator moves the nose of the airplane up or down in relation to the pilot, and perpendicular to the wings. Doing that, it both sets the pitch attitude in the turn and “pulls” the nose of the airplane around the turn. • The throttle provides thrust which may be used for airspeed to tighten the turn. • The rudder offsets any yaw effects developed by the other controls. The rudder does not turn the airplane. "The elevator .... pulls the nose of the airplane around in a turn" seems pretty close to "the elevator turns the airplane" to me.
facthunter Posted September 2, 2017 Posted September 2, 2017 IF you want to be literal, #3 is erroneous . The tightest turn is done at the slowest airspeed possible. The safe airspeed margin is a different matter, which is probably what they are alluding to. But they didn't SAY that. Nev 1
djpacro Posted September 2, 2017 Posted September 2, 2017 The tightest turn is done at the slowest airspeed possible. Really! And how do you turn at all at the slowest airspeed possible?Refer Aerodynamics of Naval Aviators pages 178-180: "The maneuver speed is the minimum speed necessary to develop aerodynamically the limit load factor and it produces the minimum turn radius within aerodynamic and structural limitations."
facthunter Posted September 2, 2017 Posted September 2, 2017 By being very familiar with the type and aware of what it's like to fly that particular plane just above the stall. It's usually full throttle with "best lift" flap extended and maximum bank without losing height. None of that contradicts what your reference says but it's written in your reference in quite complex terms. In the situation I describe, It's always slow enough in practice to confidently say the plane will stall before being structurally limited as it might well be if the manoeuver was initiated at higher than optimum speed. Gliders stay in tight thermals the same way. Nev
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 Something that has been mentioned in the past, as to current younger pilots learning to fly in real hardware, so just a curious question, not a criticism ..How many hours do you have on FSX or the like? Thanks None.
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 Your advice (born of ignorance) to use shallow bank angles in the circuit, is deadly when mis-applied. Thousands have died, and that includes plenty of instructors who thought it was a great idea to limit bank angle.Maybe you could test your instructor by asking him/her to explain the practical limitations and deadly temptations of "turning flat". Given how learned my audience is, a coordinated turn is assumed. If you mean that people turned flat, their turn was was not co-ordinated, drag increased and the inside wing was shielded from the airflow and stalled, then I already know that. 1
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 How much do you think the stall speed is increased by on a 30° "descending" base turn.Might be worth a visit to your flying school and brush up a bit of theory before suggesting everyone needs a AH for VFR flying. Get an instructor to take you up with the AH & T&B covered up - it might surprise you. Given how learned my audience is, a coordinated turn is assumed. The stall speed is higher turning with a 30 degree bank, co-ordinated turn, than descending at the same rate with wings level and not turning. To answer your question, sir, I believe that the stall speed increases by 7%. To remove any doubt, I am comparing two aircraft descending at the same rate, just one turning (coordinated, okay!), and one flying straight and not turning. If my theory needs brushing up, perhaps you would be so generous as to save me the trip to the flight school. 1 1
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 And certainly won't get to be an expert on it by looking it up.What people are saying to you here is that training and experience will teach you how to fly without those instruments. Many planes do not have them and simply do not need them. The only way to learn is to do it with an instructor sitting beside you. IMHO the more time that your eyes are outside the cockpit on base and final the safer you will be. So, how do you know if you are banked at 15 degrees and not 20 degrees without an AH? Plenty of people here saying that I don't know too much. Not so many answering my questions or correcting my statements and giving specific reasons. 1
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 Actually, bank does not increase G-forces! The elevator control is the only thing that can increase G-forces.My competition aerobatic students are judged on their angle of bank in a steep turn of 60 deg bank. 1 point off out of 10 for each 5 deg error (downgrades for other factors too) - they get top marks. Competition aerobatics is precision flying, try it sometime. Given the quality of the audience, a coordinated turn was assumed. What other sort of turn would someone fly when they turn from base on to final?
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 Yes, bank in itself does not increase "G" forces which would then affect the speed at which the wing stalls.. Stick makes the wing "work" by changing AoA. Stall is not a speed either and in equilibrium level flight, weight becomes the modifier. More weight ,more lift required so more speed to provide the lift without reaching dangerous angles of attack. Dynamic loading is the same as extra weight as far as the lift provider ( the wing) is concerned. You pull "G" and the wing must work harder. That means more speed or more AoA.If we put out an edict that we shouldn't exceed 30 degrees of bank more people will skid the plane around the turn. if they see the need to tighten the turn. If you don't know how important having balanced flight (skid ball in centre) is at high angles of attack you should not be allowed in an aeroplane that is off the ground. An AH does what a visual out the window to the front does. Allows you to easily place the plane in a particular attitude (pitch and roll) It's a help if you go into cloud but it won't save you if you don't do a few other things very right. Basic panel needs ONE gyro instrument and it's a rate turn needle. NO pilot can fly in IMC without it. Basic panel is part of IMC training. Nev Given the quality of the audience, a coordinated turn is assumed. If you can't line up with the runway with a shallow, coordinated turn, you should go round. The idea that I was advocating skidding turns beggars belief.
facthunter Posted September 2, 2017 Posted September 2, 2017 Just to put the record straight on your last post, I am in no way saying YOU do skidding turns but some people will if there's a stated limit, at say 30 degrees.. What might appear to be a safety improvement could have unintended consequences. If you wish to climb on many low powered planes or on a hot day you either climb or turn but often not both at the same time. Nev 1
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 Perhaps start with the full description of how to turn from the FAA's Airplane Flying Handbook page 3-7:"The elevator .... pulls the nose of the airplane around in a turn" seems pretty close to "the elevator turns the airplane" to me. Wrong. The elevator does not turn the airplane, the wings turn the airplane. The elevator's role is to increase the angle of attack of the wings. (If you call that turning the aircraft, well, so be it, I won't argue with you. It depends on where you go in the chain of events. It is also true to say that the pilot turns the airplane). Here is the proof that it is not the elevators that turn the aircraft: if you are gently turning right, the elevators are pushing slightly to the left! That is because elevators lift is down, in the opposite direction to the wing's lift. The wings turn the aircraft because they provide the lift, and with the airplane banked, a component of the lift is used to turn (accelerate, actually) the aircraft. The other component of the lift is used to overcome gravity. (Which is one way of looking at how come turning increases the stall speed. The wings have to accelerate the aircraft towards the centre of the turn AND continue to provide lift to keep the airplane slowly descending (or whatever you are doing)).
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 Just to put the record straight on your last post, I am in no way saying YOU do skidding turns but some people will if there's a stated limit, at say 30 degrees.. What might appear to be a safety improvement could have unintended consequences. If you wish to climb on many low powered planes or on a hot day you either climb or turn but often not both at the same time. Nev Physics say there is a limit on the angle of turns turning onto base. If you routinely do steep turns turning onto final, you will die. To clarify: you will die by stalling in said steep turn and crashing. If don't skid and don't do steep turns is a difficult message, don't blame me. 1
facthunter Posted September 2, 2017 Posted September 2, 2017 There's a communication problem there somewhere.. Nev 1
Geoff13 Posted September 2, 2017 Posted September 2, 2017 So, how do you know if you are banked at 15 degrees and not 20 degrees without an AH? Plenty of people here saying that I don't know too much. Not so many answering my questions or correcting my statements and giving specific reasons. Experience Not that a difference of 5 degrees matters. 1
kasper Posted September 2, 2017 Posted September 2, 2017 Wrong. The elevator does not turn the airplane, the wings turn the airplane. The elevator's role is to increase the angle of attack of the wings. (If you call that turning the aircraft, well, so be it, I won't argue with you. It depends on where you go in the chain of events. It is also true to say that the pilot turns the airplane). Here is the proof that it is not the elevators that turn the aircraft: if you are gently turning right, the elevators are pushing slightly to the left! That is because elevators lift is down, in the opposite direction to the wing's lift.The wings turn the aircraft because they provide the lift, and with the airplane banked, a component of the lift is used to turn (accelerate, actually) the aircraft. The other component of the lift is used to overcome gravity. (Which is one way of looking at how come turning increases the stall speed. The wings have to accelerate the aircraft towards the centre of the turn AND continue to provide lift to keep the airplane slowly descending (or whatever you are doing)). I suggest you go out and try the following 1 roll wings with aileron to around 20-30 deg. Then neutral aileron 2 pull the elevator back What I suggest will happen is When you roll in step 1 you will have wings rolling with a small heading change towards the high wing due to what is called adverse yaw When you pull back on the stick your heading will change towards the low wing Afraid this simple example - used by instructors since adam was a lad - will show that djpacro is correct. It's the elevator that principally turns your heading in conjection with roll. Rudder balanced it all but it's the roll and elevator that does the major turning work. 1
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 ExperienceNot that a difference of 5 degrees matters. That is not an answer. Try again.
APenNameAndThatA Posted September 2, 2017 Author Posted September 2, 2017 I suggest you go out and try the following1 roll wings with aileron to around 20-30 deg. Then neutral aileron 2 pull the elevator back What I suggest will happen is When you roll in step 1 you will have wings rolling with a small heading change towards the high wing due to what is called adverse yaw When you pull back on the stick your heading will change towards the low wing Afraid this simple example - used by instructors since adam was a lad - will show that djpacro is correct. It's the elevator that principally turns your heading in conjection with roll. Rudder balanced it all but it's the roll and elevator that does the major turning work. If you read my post, you will see that I AGREE with you. The elevator changes the angle of attack. That does not change the fact that it is the wings that actually turn the aircraft. The elevator changes the angle of attack of the wing, increases the lift, and it is the wing that pulls the aircraft around. Just because you move the elevator does not mean that it is the elevator that is turning the aircraft! When you pull back on the stick, the elevators go up, right, well if they go up, you are using the controls to, relatively speaking, push the tail in the OPPOSITE direction of the turn. If you move the empennage in the opposite direction to the turn, well, something else must be moving the aircraft, must it not. If you bank, then increase the wing's lift by adding flaps, you will also turn, will you not? If the elevator turns the aircraft, how can you turn the aircraft by adding lift by adding flaps? Hmm? 1
SDQDI Posted September 2, 2017 Posted September 2, 2017 Physics say there is a limit on the angle of turns turning onto base. If you routinely do steep turns turning onto final, you will die. To clarify: you will die by stalling in said steep turn and crashing.If don't skid and don't do steep turns is a difficult message, don't blame me. Doing a steep or skidding turn is in no way a prerequisite for stalling and crashing on a turn to base or final.
kasper Posted September 2, 2017 Posted September 2, 2017 Oh and if you do not believe me start chatting Cessna drivers. They are rebound through the lands as people who have no idea about rudder ... because there so so little need for it on them ... they just turn the wheel and pull back to turn corners.
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