High speed stall
Genghis the Engineer
I don't think reading the POH is very common among PPL students. It was never even mentioned to me, nor to anyone else I know.
I have a few pilots names on my plane; I photocopied the POH and ensured all of them bought a copy. But I know this is pretty rare.
Possibly a factor in why the POH is not often referenced is that it tends to be very generic and bear little relation to what is actually fitted to the aircraft.
G
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I can certainly confirm that in all schools I've ever taught in, students HAVE to read the POH. All instructors I know go through it to make sure that it is understood where information can be found.
This is essential in many ways, not least in that many FE's go through the POH with a fine toothcomb when they are on the Q and A section of the test, let alone making sure that students know as much about the a/c as possible.
I can't speak for every school obviously, but I can't imagine why somebody would not allow a student access to all the information that is required?
This is essential in many ways, not least in that many FE's go through the POH with a fine toothcomb when they are on the Q and A section of the test, let alone making sure that students know as much about the a/c as possible.
I can't speak for every school obviously, but I can't imagine why somebody would not allow a student access to all the information that is required?
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DFC
I also am having problems with your assertion that
If you are at 60 deg bank in a level banked turn the vertical component of the lift from the wing has to equal the weight of the aircraft. (assuming you are not cheating by applying some yaw to gain lift from the fuselage)
It's a long time since I did physics at school but if you are going to apply a force 60 degrees off the vertical that has a vertical component equal to the aircraft's weight then that force is going to be a heck of a lot more than 1.01 times the weight of the aircraft.
No doubt someone younger will be able to resolve the triangle of forces and tell us exactly how much G you would be pulling. I suspect it's 2g.
Mike
I also am having problems with your assertion that
It is possible to complete a 60deg bank turn at 1.01 G.......it will have a very big radius though.
It's a long time since I did physics at school but if you are going to apply a force 60 degrees off the vertical that has a vertical component equal to the aircraft's weight then that force is going to be a heck of a lot more than 1.01 times the weight of the aircraft.
No doubt someone younger will be able to resolve the triangle of forces and tell us exactly how much G you would be pulling. I suspect it's 2g.
Mike
The POH is part of the certification of the aircraft. If you have an accident while operating outside the POH, you have operated outside the certification of that aircraft and invalidated the insurance.
I always refer my students to the POH.
I always refer my students to the POH.
Mike - yes, it's 2G and stall speed is (sq rt 2 x basic stall speed) at 60 deg bank, i.e. 1.414 x basic stall speed.
Surely most FIs are able to deduce this from a triangle of forces? Or at least know that stalling speed increases with the square root of the load factor? Or am I wrong? Judging by the number of blank expressions I saw at the last FI seminar, perhaps I am indeed wrong....
Surely most FIs are able to deduce this from a triangle of forces? Or at least know that stalling speed increases with the square root of the load factor? Or am I wrong? Judging by the number of blank expressions I saw at the last FI seminar, perhaps I am indeed wrong....
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Say again slowly, there are a great many stall/spin accidents. I looked back in the bulletins and the first I came to was 5/2003. It is a fact that most light aircraft fatalities come from "Loss of control" which invariably follows some other event, leaving the pilot maxed out or at least attention diverted. Many come from low level turns on finals when either descending to land or climbing on a missed aproach. If you stall in a descending turn, the a/c is likely to flick into the turn, or in a climbing turn , flick out of the turn. I have talked many pilots (at a safe height) into this situation, and about 75% immediatley try to correct with aileron, result, stall/ spin. The reason for the flick is that in a climbing turn the outside wing is at a higher angle of attack than the inner wing, and vice versa in a descending turn. I have also noted in a high workload overshoot event many people only apply partial power. I have heard many pilots say " We never let our a/c get near these situations". Well, people do, when the workload gets too high. One answer in my opinion is to get some good quality instruction in aeros, to get to understand the envelope of the aircraft. It is all part of our armoury of self preservation.
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Dan said
I'm impressed by his ability to give a legal interpretation of a contract he hasn't seen according to the laws of a jurisdiction that has not been specified.
Might a better argument be that the POH contains information that will help you to avoid killing yourself and others?
Or have we become so materialistic that a posthumous insurance payout is valued more than life itself?
Yours, tongue in cheek
Mike
The POH is part of the certification of the aircraft. If you have an accident while operating outside the POH, you have operated outside the certification of that aircraft and invalidated the insurance.
Might a better argument be that the POH contains information that will help you to avoid killing yourself and others?
Or have we become so materialistic that a posthumous insurance payout is valued more than life itself?
Yours, tongue in cheek
Mike
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Croqueteer,
You are absolutely correct, I had a good think and trawl throught tha AAIB website and found quite a few 'loss of controls'. Knocks my assertation on the head! You've still got to try incredibly hard to spin a cessna however, amazing that people are able to do it, even under times of stress.
I am however quite happy that we no longer have to teach spinning as a matter of course, if it is done all the time, it may be too easy to treat a spinning sortie in the same manner as any flight. Just get in and go as such rather than being a bit more circumspect, especially in regard to weight and balance.
I'll definately agree about pilots using aileron to counteract a wing drop. This is highlighted on most Biennial revalidation flights with the vast majority of pilots not having practised a stall since the last time they were 'forced into it'. The stress levels in he cockpit usually go up ten fold when I mention stalling!
An aeros course is the best way of improving handling skills and confidence in as short a time as possible. Tens hours of aeros is worth fifty hours of straight and level bimbling and I wish it was made mandatory after licence issue.
You are absolutely correct, I had a good think and trawl throught tha AAIB website and found quite a few 'loss of controls'. Knocks my assertation on the head! You've still got to try incredibly hard to spin a cessna however, amazing that people are able to do it, even under times of stress.
I am however quite happy that we no longer have to teach spinning as a matter of course, if it is done all the time, it may be too easy to treat a spinning sortie in the same manner as any flight. Just get in and go as such rather than being a bit more circumspect, especially in regard to weight and balance.
I'll definately agree about pilots using aileron to counteract a wing drop. This is highlighted on most Biennial revalidation flights with the vast majority of pilots not having practised a stall since the last time they were 'forced into it'. The stress levels in he cockpit usually go up ten fold when I mention stalling!
An aeros course is the best way of improving handling skills and confidence in as short a time as possible. Tens hours of aeros is worth fifty hours of straight and level bimbling and I wish it was made mandatory after licence issue.
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An aeros course is the best way of improving handling skills and confidence in as short a time as possible. Tens hours of aeros is worth fifty hours of straight and level bimbling...
...and I wish it was made mandatory after licence issue.
At some point you've got to let the pilot get on with it. What i'd like to see is encouragement to do a few hours of instrument training and some unusual attitude training post-PPL, so even if you don't go on and do an IMC or aeros you can get yourself out of situations that your aeroplane can get itself into (with or without your help).
Greater availability of experienced instructors and suitable aeroplanes for aeros would help too (just because it can be spun doesn't mean that it is ideal, e.g. the PA28-140). They can be found, but a lot of Piper/Cessna type schools just aren't geared up for this sort of thing.
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A good point Evo, I would only like it made mandatory so that I can do more aero's rather than spending a large part of my life bashing around the circuit. Selfish reasons only I'm afraid!
A decent course in UA's(or UP's as they used to be known) would be a good idea, whilst we do it to a certain degree now, it doesn't really go into the depth I would like. It might get more people interested in aerobatics as well! Aero's in a PA28-140!! no thanks, give me a CAP 10 anyday!
Not sure I agree about a limited amount of instrument training however, it may lead to people putting themselves in situations that they haven't got the skills to deal with, but think they might since they did a few hours of instrument work. If you want to do instrument training, do the full IMC course. I'm not particlarily happy about the instrument training involved in the PPL as is.
A decent course in UA's(or UP's as they used to be known) would be a good idea, whilst we do it to a certain degree now, it doesn't really go into the depth I would like. It might get more people interested in aerobatics as well! Aero's in a PA28-140!! no thanks, give me a CAP 10 anyday!
Not sure I agree about a limited amount of instrument training however, it may lead to people putting themselves in situations that they haven't got the skills to deal with, but think they might since they did a few hours of instrument work. If you want to do instrument training, do the full IMC course. I'm not particlarily happy about the instrument training involved in the PPL as is.
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and of course there are those pilots who will never be able to perform aeros as the act of doing them incapicates them!!
Not everyone is blessed with being resistant to motion sickness. I know of many oustanding pilots who can't fly aeros for this reason but are perfectly in control of the aircraft.
I would suggest being totally proficient at the basic recovery skills is far better than believing everyone should fly aeros is the answer.
Aeros are not everyones cup of tea, same as the guy who insists on towing his house behind him on a bloody diesal escort and the guy who drives the 350HP nutty car dont understand each other but they are competant drivers.
Not everyone is blessed with being resistant to motion sickness. I know of many oustanding pilots who can't fly aeros for this reason but are perfectly in control of the aircraft.
I would suggest being totally proficient at the basic recovery skills is far better than believing everyone should fly aeros is the answer.
Aeros are not everyones cup of tea, same as the guy who insists on towing his house behind him on a bloody diesal escort and the guy who drives the 350HP nutty car dont understand each other but they are competant drivers.
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Not sure I agree about a limited amount of instrument training however, it may lead to people putting themselves in situations that they haven't got the skills to deal with, but think they might since they did a few hours of instrument work. If you want to do instrument training, do the full IMC course. I'm not particlarily happy about the instrument training involved in the PPL as is.
That's what i'm getting at. I guess "people putting themselves in situations that they haven't got the skills to deal with" could easily apply to the IMC rating as well
At risk of being pedantic it is possible to fly at 60° of bank and 1g. What's not possible is to fly a balanced level turn at 1g.
To turn you need more than 1g, and a lift vector pointed to one side of the flightpath. It happens that we prefer to do this by a level banked turn, in which case the g loading is 1/cos(bank angle).
Introduce sideslip, climb, descent, etc. and the whole thing gets much complex - and by and large we prefer not to fly like that.
G
To turn you need more than 1g, and a lift vector pointed to one side of the flightpath. It happens that we prefer to do this by a level banked turn, in which case the g loading is 1/cos(bank angle).
Introduce sideslip, climb, descent, etc. and the whole thing gets much complex - and by and large we prefer not to fly like that.
G
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Ghengis
At the risk of being pedantic, that's an oxymoron
Mmm... come to think of it, set up a descent, the rate of which increases at 32 feet per second per second and you should be able to do a perfectly balanced turn with 90 degrees angle of bank. Wouldn't be able to keep it up for long though.
Mike
it is possible to fly at 60° of bank and 1g.
To turn you need more than 1g
Mmm... come to think of it, set up a descent, the rate of which increases at 32 feet per second per second and you should be able to do a perfectly balanced turn with 90 degrees angle of bank. Wouldn't be able to keep it up for long though.
Mike
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In a level turn, g=1/Cos(angle of bank)
So at 60° AoB, g=1/cos(60) =1/½ = 2
At 75° you're puling 3.8g, so nearing structural max for most GA aircraft (but I'm sure you all knew this anyway)
Easy, no messing with triangles.
So at 60° AoB, g=1/cos(60) =1/½ = 2
At 75° you're puling 3.8g, so nearing structural max for most GA aircraft (but I'm sure you all knew this anyway)
Easy, no messing with triangles.
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Point taken, but I think (if my memory is still working) that if the a/c is legally loaded, the green band will always be within max manoeuvering. Anyway, the point of this thread is to keep things easy, and reduce the workload, which contributes greatly to flight safety.
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I agree, keep things simple !
On the subject of Va, Va actually (normally) decreases with a lighter aircraft, so say two up in a 172, Va will be around 95-99kts, where as at max all up weight it'll be around 110kts. The green band probably stretches to 130ish kts in a 172, so lightly loaded you run more risk of causing structural damage by control inputs....
Any maneuvre, such as steep turns, lazy 8's etc., should be entered at or below Va for the configuration to ensure no structural damage can occour.
Cheers
EA
On the subject of Va, Va actually (normally) decreases with a lighter aircraft, so say two up in a 172, Va will be around 95-99kts, where as at max all up weight it'll be around 110kts. The green band probably stretches to 130ish kts in a 172, so lightly loaded you run more risk of causing structural damage by control inputs....
Any maneuvre, such as steep turns, lazy 8's etc., should be entered at or below Va for the configuration to ensure no structural damage can occour.
Cheers
EA