The rubbish taught by flying instructors.
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There's an interesting article in the Flight Safety Australia mag that mentions this in their cover story "17 Aviation Myths Dispelled". Here's the whole article (it's a PDF so you'll need Adobe Acrobat Reader) but I'll quote a few paragraphs from it here;
Myth 9: Attitude controls airspeed
.. So, what really is the technique that should be used? Easy – the flight controls manage the aircraft’s flight path and the thrust controls the aircraft’s speed.
The technique applies to all phases of flight, not just the ILS, where one datum is not a fixed value, like thrust may be in some circumstances such as a climb. It applies in the visual circuit where the base turn point should be the extension of a visual 3 degree glide path from the runway turned through 180 degrees.
Flying a precise visual circuit is more demanding and requires higher skill levels than flying an ILS because the electronic cues are not there to guide you. A visual circuit requires you to determine the base turn point, configure the aircraft for the base/final approach, fly the aircraft at a constant descent rate as a function of ground speed (five times the ground speed for the descent rate) and achieve the desired airspeed schedule with power.
The CASA assessment guide in the day VFR syllabus requires “co-ordinated use of power and nose attitude are applied to approach path angle speed”.
Where did this idea of attitude controlling airspeed come from? It probably had it’s genesis during World War 2 when intensive training had to be conducted over short periods; and when – irrespective of aircraft type or performance – the aerodynamic characteristics of most aircraft were similar.
.. So, what really is the technique that should be used? Easy – the flight controls manage the aircraft’s flight path and the thrust controls the aircraft’s speed.
The technique applies to all phases of flight, not just the ILS, where one datum is not a fixed value, like thrust may be in some circumstances such as a climb. It applies in the visual circuit where the base turn point should be the extension of a visual 3 degree glide path from the runway turned through 180 degrees.
Flying a precise visual circuit is more demanding and requires higher skill levels than flying an ILS because the electronic cues are not there to guide you. A visual circuit requires you to determine the base turn point, configure the aircraft for the base/final approach, fly the aircraft at a constant descent rate as a function of ground speed (five times the ground speed for the descent rate) and achieve the desired airspeed schedule with power.
The CASA assessment guide in the day VFR syllabus requires “co-ordinated use of power and nose attitude are applied to approach path angle speed”.
Where did this idea of attitude controlling airspeed come from? It probably had it’s genesis during World War 2 when intensive training had to be conducted over short periods; and when – irrespective of aircraft type or performance – the aerodynamic characteristics of most aircraft were similar.
Thread Starter
Where did this idea of attitude controlling airspeed come from
Service Pilot's Notes for most of the wartime types gave approach speeds for both glide and powered landing approaches - the glide approach being slightly faster to allow for the greater inertia during the flare. In these cases airspeed was controlled by elevator. As of course is climb speed given a set climb power setting. With advanced trainers such as the Harvard and Wirraway, the glide approach became much more demanding than for Moths due to higher rate of descent and more pronounced flare and so powered approaches became the recommended procedure. Now a combination of power and elevator was used to control the speed and rate of descent rather like flying an ILS or VASIS.
The big problem with a power off glide as in the early aero club training (which in turn came from Service instructors), was the sudden reduction in airspeed near the ground due to wind gradient -if the wind was gusty. This could either be resolved by lowering the nose to regain lost airspeed or introduce power to recover the energy. Lowering the nose was fine unless you were close to the deck when you might not have the height in hand to get back to the original speed. So you had to fall back on power to recover lost speed.
On the other hand if during the glide approach it was obvious on early final you were not going to get in because you had cocked up your judgement, you then applied cruise power and flew level until you intercepted the ideal glide angle - then you simply re-closed the throttle and resumed the glide again. Very simple and efficient.
Powered approaches in early aircraft such as the Moths, Austers and Chipmunks were conducted by first full closing the throttle in level flight early on base leg and a glide commenced (airspeed controlled by elevator) then at some point on final when it was clear an undershoot was occurring, the power was re-introduced and lo and behold there was your powered approach.
Different technique to nowadays where depending on the whims or experience of the instructor, the student pulls on carb heat on early base which drops the rpm a bit - then reduces power to something like 1500rpm causing reduction in speed in level flight - then sticks down a bit of flap- then pulls back the airspeed a bit more - then a bit more flap - then take a bit of power off - then carb heat to cold which increases the rpm a bit - then aim at yet another airspeed until it all comes together around 300 ft on final if you are lucky. Much more complicated than it needs to be compared with the original glide approach technique.
I really do go on, don't I??
Last edited by Centaurus; 17th Dec 2006 at 10:57.
Grandpa Aerotart
The corollary of what Centuarus is saying is the way I was taught to fly a lighty and they way I do to this day when in my Bonanza...I make one power reduction on late downwind and then fly attitude for flight path and add drag, gear+flaps, to control speed (rate of decay) down to a point on very short finals where I might make a few small power changes to control my speed while still using attitude to control my flight path...if I jag it all perfectly though I make just two power changes, one on downwind, back to about 15in MP, and another one, all the way off, as I begin round out.
The CASA assessment guide in the day VFR syllabus requires “co-ordinated use of power and nose attitude are applied to approach path angle speed”.
Co-ordinated use of power and nose attitude. Words to live by newbies.
To me, this speed/attitude thing appears to be a pointless argument. I was taught attitude for airspeed and power for profile and it seemed to work just fine in a C150, Warrior and so on. Since there are two variables attitude and power at work to determine flight path at once, it makes sense to hold one constant and then play with the other. I can imagine in a large jet its better to hold a constant attitude.
Smaller aircraft change their speed quite readily with a change of attitude and I was taught to trim the aircraft on base at somewhere between 70-90 knots with two stages of flaps and about 1700 rpm or 15 in MAP or suchlike and in most aircraft this gives an ROD of no more than 500fpm although more is available.
Power was increased if necessary to slow ROD and remain at a constant speed by raising the nose very slightly to ensure the turn to final was completed by 500 ft AGL.
On final, usually the third stage of flaps and maintain constant speed by lowering the nose a bit. If we are undershooting, add power and raise the nose slightly to maintain constant speed. If overshooting reduce power and lower the nose to maintain constant speed.
300 ft AGL is my decsiion point and I commit to land if the approach and all else is OK. PUF, carb heat or whatever, I always tell a passenger that if I screw it up I'll go around and that this is a normal manouvre since nobody's perfect.
From there the nose comes up slightly and power is reduced to get the aircraft to slow up to whatever target Vref is to be used. If necessary juggle power to maintain aimpoint but keep speed constant at Vref. At fifty feet start bringing back the power to whatever depending on aircraft type and Bob's your uncle.
In other words, for a constant approach speed, attitude and power are inextricably linked. Add more power and your approach must get shallower if you are to maintain that constant sped. Reduce power and your approach must get steeper if you are to maintain that constant speed.
At least thats the way this twisted person sees it, and it seems to work for me. I'm sure there are plenty of other ways of doing it, some quite dramatic, but I'd prefer to save those for emergencies.
OK, tear me to shreds.
Smaller aircraft change their speed quite readily with a change of attitude and I was taught to trim the aircraft on base at somewhere between 70-90 knots with two stages of flaps and about 1700 rpm or 15 in MAP or suchlike and in most aircraft this gives an ROD of no more than 500fpm although more is available.
Power was increased if necessary to slow ROD and remain at a constant speed by raising the nose very slightly to ensure the turn to final was completed by 500 ft AGL.
On final, usually the third stage of flaps and maintain constant speed by lowering the nose a bit. If we are undershooting, add power and raise the nose slightly to maintain constant speed. If overshooting reduce power and lower the nose to maintain constant speed.
300 ft AGL is my decsiion point and I commit to land if the approach and all else is OK. PUF, carb heat or whatever, I always tell a passenger that if I screw it up I'll go around and that this is a normal manouvre since nobody's perfect.
From there the nose comes up slightly and power is reduced to get the aircraft to slow up to whatever target Vref is to be used. If necessary juggle power to maintain aimpoint but keep speed constant at Vref. At fifty feet start bringing back the power to whatever depending on aircraft type and Bob's your uncle.
In other words, for a constant approach speed, attitude and power are inextricably linked. Add more power and your approach must get shallower if you are to maintain that constant sped. Reduce power and your approach must get steeper if you are to maintain that constant speed.
At least thats the way this twisted person sees it, and it seems to work for me. I'm sure there are plenty of other ways of doing it, some quite dramatic, but I'd prefer to save those for emergencies.
OK, tear me to shreds.
Last edited by Sunfish; 17th Dec 2006 at 22:14.
When you live....
Guys,
I think there is some confusion as to what is taught to ab-initio students, 'heavy' pilots and how the world actually works.
Attitude for airspeed, power for height is exactly the right thing to teach a newbie - it allows them to diagnose a problem (speed or height) and select an approptiate response (attitude or power). This method provides continuity of logic with how they climb - too fast, pull up, too slow, push down.
I'm just being introduced to the 'heavy' concept of attitude as described by others for use in a/c as small as a P32, Bo, C210 etc and find it works equally as well (if not better for me). Chimbu and others indicate that this is the right approach as the a/c get bigger and bigger but there is nothing wrong with flying your 150 this way either - there is just a disconnect between how your head works in the approach as opposed to the climb.
But the way the plane actually needs to be flown is of course via "the coordinated use of power and attitude" (attitude + power = performance) and as you get more experience and whichever of power or attitude you lead with, the other will follow instinctively and immediately to compensate for the known impending secondary effects.
Recognise the "attitude for ...... blah blah" sayings for what they are - a guide to get you making a positive identification of your situation and acting on it - and not as a strict instruction on how to fly the thing! This thread is becoming another great example of how to overcomplicate things!
Rant over,
UTR.
I think there is some confusion as to what is taught to ab-initio students, 'heavy' pilots and how the world actually works.
Attitude for airspeed, power for height is exactly the right thing to teach a newbie - it allows them to diagnose a problem (speed or height) and select an approptiate response (attitude or power). This method provides continuity of logic with how they climb - too fast, pull up, too slow, push down.
I'm just being introduced to the 'heavy' concept of attitude as described by others for use in a/c as small as a P32, Bo, C210 etc and find it works equally as well (if not better for me). Chimbu and others indicate that this is the right approach as the a/c get bigger and bigger but there is nothing wrong with flying your 150 this way either - there is just a disconnect between how your head works in the approach as opposed to the climb.
But the way the plane actually needs to be flown is of course via "the coordinated use of power and attitude" (attitude + power = performance) and as you get more experience and whichever of power or attitude you lead with, the other will follow instinctively and immediately to compensate for the known impending secondary effects.
Recognise the "attitude for ...... blah blah" sayings for what they are - a guide to get you making a positive identification of your situation and acting on it - and not as a strict instruction on how to fly the thing! This thread is becoming another great example of how to overcomplicate things!
Rant over,
UTR.
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Confusion
Unless you change POWER to vary the climb (Vx, Vy) then I would have to say that ATTITUDE controls AIRSPEED.
In S&L a reduction in POWER requires a corresponding increase in ATTITUDE resulting in a reduction in SPEED. Some would say ‘co-ordinated use of power and nose attitude’.
A student is taught to descend at a selected ATTITUDE to maintain SPEED and adjust the POWER to control the RATE.
A glide is very close to the straight and level ATTITUDE with recovery to S&L effected by holding the ATTITUDE and increasing the POWER to arrest the rate of descent. In a glide there is no alternative but to recover SPEED with ATTITUDE.
Flying ATTITUDE’s is the basis of controlling the aeroplane and is first taught at O & E C.
Navy pilots and STOL operators flying at minimum-control speeds have no excess airspeed to trade for altitude. Power is the only option to reduce rate of descent.
The ‘ballistic’ approach (for want of a better name) will work on any aircraft that has power available and is carrying a margin of speed above the stall, BUT it must be brought to the students attention that we are applying a different technique lest the student come to grief in a STOL or glide situation.
Schools teach the ‘ballistic’ approach if their students are airline cadets or under some belief that it will achieve solo earlier. That’s OK but the student should have a solid grasp of the ATTITUDE –v- SPEED relationship first. He/she should be able to demonstrate that if ROD is high prior to touchdown POWER will be applied to either CONTROL the descent or go-around.
If you must teach the ‘ballistic’ approach in a trainer why not teach the standard method all the way around the circuit until established on final and then say “We are now adopting the ‘ballistic’ approach technique. Hold the aiming point constant in the windscreen and adjust your speed with power.”
Both are valid techniques but shouldn’t be allowed to complicate issues with students - or STOL pilots for that matter.
In S&L a reduction in POWER requires a corresponding increase in ATTITUDE resulting in a reduction in SPEED. Some would say ‘co-ordinated use of power and nose attitude’.
A student is taught to descend at a selected ATTITUDE to maintain SPEED and adjust the POWER to control the RATE.
A glide is very close to the straight and level ATTITUDE with recovery to S&L effected by holding the ATTITUDE and increasing the POWER to arrest the rate of descent. In a glide there is no alternative but to recover SPEED with ATTITUDE.
Flying ATTITUDE’s is the basis of controlling the aeroplane and is first taught at O & E C.
Navy pilots and STOL operators flying at minimum-control speeds have no excess airspeed to trade for altitude. Power is the only option to reduce rate of descent.
The ‘ballistic’ approach (for want of a better name) will work on any aircraft that has power available and is carrying a margin of speed above the stall, BUT it must be brought to the students attention that we are applying a different technique lest the student come to grief in a STOL or glide situation.
Schools teach the ‘ballistic’ approach if their students are airline cadets or under some belief that it will achieve solo earlier. That’s OK but the student should have a solid grasp of the ATTITUDE –v- SPEED relationship first. He/she should be able to demonstrate that if ROD is high prior to touchdown POWER will be applied to either CONTROL the descent or go-around.
If you must teach the ‘ballistic’ approach in a trainer why not teach the standard method all the way around the circuit until established on final and then say “We are now adopting the ‘ballistic’ approach technique. Hold the aiming point constant in the windscreen and adjust your speed with power.”
Both are valid techniques but shouldn’t be allowed to complicate issues with students - or STOL pilots for that matter.
Thread Starter
A glide is very close to the straight and level ATTITUDE
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But try a glide, flaps up and holding best glide speed (about 60 knots) in the same aircraft and see how close the nose attitude is to S & L. In the same aircraft you will find that to hold the glide speed will require full back trim (or close to it) if my memory serves, and a subsequent application of power to 2300 RPM will result in much forward pressure and little or no change of attitude to achieve level flight and cruise speed.
One doesn't normally glide with full flap if one is attempting to achieve best gliding range, one 'approaches' with full flap!
(Sigh) Centaurus, by "decision point" and "committing to land", I mean that at this point (300 feet) I again ask myself if my approach is stable, at the correct speed and attitude, on the correct runway(don't laugh), aircraft configured correctly (PUF), aimpoint correctly selected, traffic sorted, passenger briefed, no animals or other stuff on the runway and mentally in control of the situation (ie: Happy).
If the answer to all this is "yes' I press on, otherwise I go around. My experience of systemic failures in various non aviation situations strongly suggests to me that if everything isn't "sorted" by 300 feet then I am an accident waiting to happen. I want nothing on my mind from 300 feet other than performing a suitable landing, taxiing to the appropriate location and shutting down. Surely you agree?
I always take care to avoid inadvertantly putting myself under pressure and making use of conscious decision points is a good way of doing it in my humble opinion. The times I have really screwed up in an aircraft is when I have been indecisive and haven't mentally planned ahead.
P.S. I sometimes go around anyway just for the practice.
If the answer to all this is "yes' I press on, otherwise I go around. My experience of systemic failures in various non aviation situations strongly suggests to me that if everything isn't "sorted" by 300 feet then I am an accident waiting to happen. I want nothing on my mind from 300 feet other than performing a suitable landing, taxiing to the appropriate location and shutting down. Surely you agree?
I always take care to avoid inadvertantly putting myself under pressure and making use of conscious decision points is a good way of doing it in my humble opinion. The times I have really screwed up in an aircraft is when I have been indecisive and haven't mentally planned ahead.
P.S. I sometimes go around anyway just for the practice.
Dont upgrade you FCL to a CPL and fly charter then sunny, you will still be smoking along at 300 ft and be doing everything between 50-100feet
A go around? almost unheard of up here, if someone hasnt cleared off the runway in front of you, you conduct an orbit short finals or if there is enough room to land, land anyway
I again ask myself if my approach is stable, at the correct speed and attitude, on the correct runway (don't laugh), aircraft configured correctly (PUF), aimpoint correctly selected, traffic sorted, passenger briefed, no animals or other stuff on the runway and mentally in control of the situation (ie: Happy).
If your approach is already stabilised, then what else needs to be done? Just fly the the fecking thing. Why is it this complicated? It's a C152 for god sake.
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My bad 4SPOOLED. My reading of your post was your conduct orbits at 300' if the runway is not clear.
Firstly I am not sure who mention a C152 at all, but everyone has their own personal minima. I am sure that even those who fly up north and have there decision height as 5' did not start that way.
I think Sunfish is doing a good thing that he even considers that stuff at all. Too many people don't for whatever reason. How low you go really depends on how comfortable you are with your aircraft, how current/recent you are on type, weather, etc etc. Also familiarity of the airfield, traffic and perhaps knowing the other pilots should also all influence where you make your decisions. As a charter pilot, I would like to think that if it was all going pear shaped you would elect to go around higher than zot feet.
I recently was a pax on board a 738 into Perth that conducted a go around due windshear and heard people around me speculate on all sorts of things. Perhaps the gear wasn't down, maybe it wasn't really the runway etc etc. I just think its better to fix it earlier than give them a thrill ride to the deck and then conducting a GA.
As to how you operate by yourself, again it comes back to what you're comfortable with.
Firstly I am not sure who mention a C152 at all, but everyone has their own personal minima. I am sure that even those who fly up north and have there decision height as 5' did not start that way.
I think Sunfish is doing a good thing that he even considers that stuff at all. Too many people don't for whatever reason. How low you go really depends on how comfortable you are with your aircraft, how current/recent you are on type, weather, etc etc. Also familiarity of the airfield, traffic and perhaps knowing the other pilots should also all influence where you make your decisions. As a charter pilot, I would like to think that if it was all going pear shaped you would elect to go around higher than zot feet.
I recently was a pax on board a 738 into Perth that conducted a go around due windshear and heard people around me speculate on all sorts of things. Perhaps the gear wasn't down, maybe it wasn't really the runway etc etc. I just think its better to fix it earlier than give them a thrill ride to the deck and then conducting a GA.
As to how you operate by yourself, again it comes back to what you're comfortable with.
Bugsmasherdriverandjediknite
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As or assuming that we fly around at 300ft pffffft even a GFPT student knows you dont below 500agl except under stress of weather, and even then the pucker factor is maxed out.
Christ on a push bike!!. use what ya need and don't use what ya don't need.
Take flap when you require it..... not when your at a predetermined point in the circuit, put your gear down when its required, open your cowl flaps when they need to be opened, leave your mags the **** alone (they were working a second ago and give plenty of notice when they stop working) pretty easy really.
(my own personal thoughts on making people check gear down and locked on a fixed gear aircraft, is it teaches them complacency and also prompts one to use the check, but not actually check........... because we all know the gear will be there).
As a charter pilot, I would like to think that if it was all going pear shaped you would elect to go around higher than zot feet.
Yes I know that. I meant if its crap at 200' are you going to wait to you hit 50' to do something about it?
I give up do whatever makes you happy.
I give up do whatever makes you happy.
leave your mags the **** alone (they were working a second ago and give plenty of notice when they stop working
my own personal thoughts on making people check gear down and locked on a fixed gear aircraft, is it teaches them complacency and also prompts one to use the check, but not actually check........... because we all know the gear will be there
ing point?Might as well add "disarm doors" in the after landing check too
