Best Single Engine Glider?
Power can only achieve lift through thrust.
"an airplane with a windmilling propeller glides farther and differently than an airplane with a stopped propeller"
With respect to the glide ratio of the airplane and it's L/D ratio, while in perfect theory the two may be considered mathematically identical, they're not. An airplane in a power off condition which provides a given glide ratio does not provide an equivilent indication of the drag to be overcome in a powered situation, considering the windmiling propeller. A windmilling prop will generate drag in excess of a plywood disc out there, of the same diameter as the prop...that's a lot of drag. To attempt to make a comparison between a gliding airplane with a wind milling prop, and the power required to sustain flight is not the same, and not comparable (is not identical) to the drag incurred in a power-off, windmilling glide.
As an example of a worse-case scenario in a light single, I flew a polish M18 Dromader for about seven years, with several different types of powerplants. These were turbine, but piston vs. turbine is really irrelevant here. With a TPE-331-10 powered airplane, retarding the power to idle produced a glide ratio of approximately 1-2:1; from level flight the airplane could slow down so quickly it would throw me forward in the harness and required application of full forward stick to keep from stalling. It was a useful characteristic for the type of flying we were doing, which involved high angle descents into terain, etc. (not a desireable characeristic in a typical light pleasure airplane).
Despite such a dismal glide ratio, the airplane had excellent performance with the power pushed up. The drag which caused the poor glide ratio was due to the propeller at idle, in a windmilling state. (it wasn't particularly impressive in a failed windmilling state either as I can attest from experience). To equate the glide ratio with the power required to fly the airplane would be a highly incongruous. The L/D ratio in a glide isn't comparable to the L/D ratio under power...and one cannot simply say that an airplane with a small powerplant and a poor glide ratio can't be made to fly on that small power...because the power required to fly isn't the same as the power to overcome the drag in the glide. There's less drag in a powered condition. Glide ratio doesn't necessarily equate to a powered state.
Another airplane which I used to fly, which is no longer in service, was a large four engine airplane with radial piston power. One engine at idle, not feathered, could prevent sustained level flight on the remaining three. While most here aren't going to be flying that kind of an airplane, it's an example of a situation in which only one quarter of the available propellers are producing windmilling drag and yet the airplane is still in a highly impaired state...with three more identical engines still functioning perfectly, attempting to sustain flight. The windmilling prop can produce substantial drag which isn't present during a powered state when the engine is driving the prop...to suggest that the power required to sustain flight is comparable to the drag produced in a windmilling glide is incorrect, and that applies to a light single as much as a large four engine recip.
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"Power doesn't achieve lift"
Try telling that to a helicopter pilot.
It does not directly achieve lift. However lift cannot be produced without power, and power produces lift by causing net airflow over the wings. This is achieved in various fashions (I can think of 4 off the top of my head), although for now we are talking about by its use to produce thrust to overcome drag and keep the aircraft with fixed wings moving through the air.
Unless you really are not keeping up with the physics here you are quite aware that my words were short hand. Do I really need to go into detailed, pedantic description, like the previous paragraph, of every idea every time I mention it, even when I have already explained it before?
Yes a windmilling prop provides prop drag. However an engine has to overcome prop drag in order to provide thrust, that is one of the inefficiencies we both alluded to. Therefore it is on both sides of the equation and cancels out (in fact it saps thrust in the powered aircraft by more than the increase of drag after engine failure, as the prop is driven faster).
However all this proves is that you are over complicating the matter. I was never making any attempt to precisely calculate thrust or maximum lift. I was using figures of the correct order of magnitude but deliberately conservative assumptions to simplify the problem to prove that there is no way that an aircraft with typical power to weight ratio of light aircraft could fly level if its glide ratio was 3:1. This I have adequately shown. You are simply nitpicking, and have not addressed the central point.
Using a back-of-the-envelope calculation, simplified but with either conservative or realistic assumptions to either constrain or approximate the answer to a problem is a common technique in physics (conservative assumptions to constrain, realistic assumptions to approximate). I remember at university for example being shown that you could work out in a few seconds how long it takes to boil an egg, from basic priciples and the properties of the egg. It is not meant to be an accurate representation of heat flow in an ovoid shape and does not even attempt to model the denaturing of albumen proteins. However it comes up with about the right figure (I think we got 5 minutes).
What is the relevance of an M18 Dromader to "most light aircraft" that you first posted about? That is a piece of drag-inducing ironwork with a huge engine on the front and a massive prop. It doesn't have the power to weight ratio of a Cessna 172, so of course my scratch calculation is not relevant.
Likewise how is a "large four engine airplane with radial piston power" relevant to most light aircraft?
Try telling that to a helicopter pilot.
It does not directly achieve lift. However lift cannot be produced without power, and power produces lift by causing net airflow over the wings. This is achieved in various fashions (I can think of 4 off the top of my head), although for now we are talking about by its use to produce thrust to overcome drag and keep the aircraft with fixed wings moving through the air.
Unless you really are not keeping up with the physics here you are quite aware that my words were short hand. Do I really need to go into detailed, pedantic description, like the previous paragraph, of every idea every time I mention it, even when I have already explained it before?
Yes a windmilling prop provides prop drag. However an engine has to overcome prop drag in order to provide thrust, that is one of the inefficiencies we both alluded to. Therefore it is on both sides of the equation and cancels out (in fact it saps thrust in the powered aircraft by more than the increase of drag after engine failure, as the prop is driven faster).
However all this proves is that you are over complicating the matter. I was never making any attempt to precisely calculate thrust or maximum lift. I was using figures of the correct order of magnitude but deliberately conservative assumptions to simplify the problem to prove that there is no way that an aircraft with typical power to weight ratio of light aircraft could fly level if its glide ratio was 3:1. This I have adequately shown. You are simply nitpicking, and have not addressed the central point.
Using a back-of-the-envelope calculation, simplified but with either conservative or realistic assumptions to either constrain or approximate the answer to a problem is a common technique in physics (conservative assumptions to constrain, realistic assumptions to approximate). I remember at university for example being shown that you could work out in a few seconds how long it takes to boil an egg, from basic priciples and the properties of the egg. It is not meant to be an accurate representation of heat flow in an ovoid shape and does not even attempt to model the denaturing of albumen proteins. However it comes up with about the right figure (I think we got 5 minutes).
What is the relevance of an M18 Dromader to "most light aircraft" that you first posted about? That is a piece of drag-inducing ironwork with a huge engine on the front and a massive prop. It doesn't have the power to weight ratio of a Cessna 172, so of course my scratch calculation is not relevant.
Likewise how is a "large four engine airplane with radial piston power" relevant to most light aircraft?
"Power doesn't achieve lift"
Try telling that to a helicopter pilot.
Try telling that to a helicopter pilot.
However lift cannot be produced without power, and power produces lift by causing net airflow over the wings.
Yes a windmilling prop provides prop drag. However an engine has to overcome prop drag in order to provide thrust, that is one of the inefficiencies we both alluded to. Therefore it is on both sides of the equation and cancels out (in fact it saps thrust in the powered aircraft by more than the increase of drag after engine failure, as the prop is driven faster).
However all this proves is that you are over complicating the matter. I was never making any attempt to precisely calculate thrust or maximum lift. I was using figures of the correct order of magnitude but deliberately conservative assumptions to simplify the problem to prove that there is no way that an aircraft with typical power to weight ratio of light aircraft could fly level if its glide ratio was 3:1. This I have adequately shown. You are simply nitpicking, and have not addressed the central point.
What is the relevance of an M18 Dromader to "most light aircraft" that you first posted about? That is a piece of drag-inducing ironwork with a huge engine on the front and a massive prop. It doesn't have the power to weight ratio of a Cessna 172, so of course my scratch calculation is not relevant.
Likewise how is a "large four engine airplane with radial piston power" relevant to most light aircraft?
You seem to miss the point, or even make light of it by suggesting that the drag which causes the low glide ratio has an identical effect in robbing engine performance such that the glide and the powered level flight or climb are handicapped in the same manner. This is simply not true.
For the original poster, again, the fact remains that the glide ratio is really unimportant; it's the landing at the end which counts, and once more, this is entirely within the purview of the pilot.
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How does one produce lift without power?
Power is required for autorotation, otherwise one could autorotate and remain level. I suggest you find a physics text book and look up the meaning of the word power. I can assure you it will talk about conversion of energy. Energy can be in the form of potential energy or in the form of chemical energy before its conversion, but power is by definition simply a rate of conversion of energy.
To try and simplify things for you we'll take a glide speed of 70 kts. At a glide ratio of 3:1 that means a rate of descent of 2363 feet per minute. That is not a rate i would like to see in a light aircraft.
Perhaps you could, instead of trying to nitpick minor factors in a calculation that was never meant to be accurate, factors that are overwhelmed by the scale of extra thrust needed to lift your 3:1 L:D ratio aircraft, you could suggest one that has that ratio.
I have looked up the C152 again, and the estimate I found was 8.75:1 (pretty close to the 9:1 I mentioned earlier). So where are your examples of "most" light aircraft at 6:1? Where is the normal light aircraft, relevant to private flying, with a 3:1 lift to drag ratio?
Power is required for autorotation, otherwise one could autorotate and remain level. I suggest you find a physics text book and look up the meaning of the word power. I can assure you it will talk about conversion of energy. Energy can be in the form of potential energy or in the form of chemical energy before its conversion, but power is by definition simply a rate of conversion of energy.
To try and simplify things for you we'll take a glide speed of 70 kts. At a glide ratio of 3:1 that means a rate of descent of 2363 feet per minute. That is not a rate i would like to see in a light aircraft.
Perhaps you could, instead of trying to nitpick minor factors in a calculation that was never meant to be accurate, factors that are overwhelmed by the scale of extra thrust needed to lift your 3:1 L:D ratio aircraft, you could suggest one that has that ratio.
I have looked up the C152 again, and the estimate I found was 8.75:1 (pretty close to the 9:1 I mentioned earlier). So where are your examples of "most" light aircraft at 6:1? Where is the normal light aircraft, relevant to private flying, with a 3:1 lift to drag ratio?
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LMS / SN3
Admittedly some of what you are saying are slightly over and above my little head, but as long as the conversation is conducted in a good and friendly spirit then it's terrific reading which I'm trying to understand.
As for my original question, SN3's answer was more than sufficient as he managed to put my mind at ease with a detailed explanation and some 1st hand experience examples.
Thanks.
Admittedly some of what you are saying are slightly over and above my little head, but as long as the conversation is conducted in a good and friendly spirit then it's terrific reading which I'm trying to understand.
As for my original question, SN3's answer was more than sufficient as he managed to put my mind at ease with a detailed explanation and some 1st hand experience examples.
Thanks.
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Only his answer is wrong, Vabsie. The examples he gives are not relevant, as they are not typical light aircraft. I am not sure why he mentions single-seat agricultural plane I have never heard of in 20 years involvement in a variety of sides of aviation to a question in private flying.
Typical light aircraft have a much better glide ratio than he suggests, which is important to people who are planning flights, especially if there are areas where an engine failure would lead to a difficult landing - over water, woodland, mountains or other rough terrain. I have a friend who managed to glide just clear of the rough moorland hillside he had an engine failure over. Poor glide ration would have meant he could not have made the glide off the hills, and had he thought like that he would have concentrated on the wrong thing, minimising impact in a poor location, rather than achieving a safe landing in a good one.
SN3 also concentrates on prop drag, which is a problem that can be overcome but is also not as dominant as he suggests. Stopping a propellor cancels out 95% of prop drag, and can be achieved in a light aircraft. However a decision has to be made to do that or concentrate on the glide. Shutting down an engine in a light twin all commercial pilots train in at some point is far more relevant as a demonstration of the prop drag of a light single (similar power per engine) than one of four large radials in a big aircraft. Prop drag is important, but really ain't as much as he suggests. If it was it would be really important to stop the propellor in the glide, but except in marginal conditions it is not.
SN3
Forgot to mention that with that large prop the airflow is much slower than the little prop on a normal light single, so the sum changes giving more thrust under power as well as more drag when windmilling. In fact airflow is something I reckon, on further consideration, I over-estimated in my original equation so the thrust limit is higher than I had guessed. However not by enough to actually let the aircraft fly in practice! In fact a scratch calculation which takes that into account, using just pure Newtonian mechanics of energy and momentum brings in some fundamental physical limitations to efficiency due to speed of airflow. Through a typical 78" diameter prop this gives an even lower thrust limit, around 2,200 N. So actual thrust must be well under 2000 N.
Worked with a larger prop the force gets higher of course (because energy relates to velocity squared, momentum only to velocity, so the same energy produces less change of momentum if the speed change is higher. Force equates to rate of change of momentum), and with a helicopter rotor diameter much higher still, which is how it can fly.
Typical light aircraft have a much better glide ratio than he suggests, which is important to people who are planning flights, especially if there are areas where an engine failure would lead to a difficult landing - over water, woodland, mountains or other rough terrain. I have a friend who managed to glide just clear of the rough moorland hillside he had an engine failure over. Poor glide ration would have meant he could not have made the glide off the hills, and had he thought like that he would have concentrated on the wrong thing, minimising impact in a poor location, rather than achieving a safe landing in a good one.
SN3 also concentrates on prop drag, which is a problem that can be overcome but is also not as dominant as he suggests. Stopping a propellor cancels out 95% of prop drag, and can be achieved in a light aircraft. However a decision has to be made to do that or concentrate on the glide. Shutting down an engine in a light twin all commercial pilots train in at some point is far more relevant as a demonstration of the prop drag of a light single (similar power per engine) than one of four large radials in a big aircraft. Prop drag is important, but really ain't as much as he suggests. If it was it would be really important to stop the propellor in the glide, but except in marginal conditions it is not.
SN3
Forgot to mention that with that large prop the airflow is much slower than the little prop on a normal light single, so the sum changes giving more thrust under power as well as more drag when windmilling. In fact airflow is something I reckon, on further consideration, I over-estimated in my original equation so the thrust limit is higher than I had guessed. However not by enough to actually let the aircraft fly in practice! In fact a scratch calculation which takes that into account, using just pure Newtonian mechanics of energy and momentum brings in some fundamental physical limitations to efficiency due to speed of airflow. Through a typical 78" diameter prop this gives an even lower thrust limit, around 2,200 N. So actual thrust must be well under 2000 N.
Worked with a larger prop the force gets higher of course (because energy relates to velocity squared, momentum only to velocity, so the same energy produces less change of momentum if the speed change is higher. Force equates to rate of change of momentum), and with a helicopter rotor diameter much higher still, which is how it can fly.
Only his answer is wrong, Vabsie. The examples he gives are not relevant, as they are not typical light aircraft. I am not sure why he mentions single-seat agricultural plane I have never heard of in 20 years involvement in a variety of sides of aviation to a question in private flying.
SN3 also concentrates on prop drag, which is a problem that can be overcome but is also not as dominant as he suggests. Stopping a propellor cancels out 95% of prop drag, and can be achieved in a light aircraft. However a decision has to be made to do that or concentrate on the glide. Shutting down an engine in a light twin all commercial pilots train in at some point is far more relevant as a demonstration of the prop drag of a light single (similar power per engine) than one of four large radials in a big aircraft. Prop drag is important, but really ain't as much as he suggests. If it was it would be really important to stop the propellor in the glide, but except in marginal conditions it is not.
What you have dragged into the conversation, needlessly and incorrectly, is the assertion that an airplane with a low glide ratio and the power to weight ratio of a typical light airplane couldn't fly...and that's not true. The fact is that the glide ratio of the airplane with a windmilling propeller has no bearing on the capability of the airplane to fly when under it's own power. It doesn't.
That's the point of the Dromader, in fact....used because it's a light single with a very low glide ratio under certain installations (as previously repeatedly described), the same power to weight ratio as the Cessna 172 you invoked, yet flies very well under it's own power...because the glide ratio has no bearing on the way it flies under it's own power.
Most light airplanes do well without power, because power doesn't create lift, contrary to your own assertions, and can easily trade altitude for airspeed (and thus lift) without any benifit of engine power or thrust, and even in the presence of propeller drag.
There's a reason why some propellers are featherable...because drag is so high.
Point being, your original assertions are incorrect, in the parallel you attempted to draw between powered flight and a windmilling glide. Most light airplane glide ratios are provided given a windmilling glide...and any references to stopped propellers are thus irrelevant to the discussion. You attempted to state that an airplane with a low glide ratio simply can't fly given the power a typical light airplane has...and clearly you're wrong....just as you're incorrect regarding the amount of drag a windmilling propeller creates and the energy it absorbs...again, in excess of the equivilent flat-plate area of the prop disc in many cases.
Forgot to mention that with that large prop the airflow is much slower than the little prop on a normal light single, so the sum changes giving more thrust under power as well as more drag when windmilling.
Shutting down an engine in a light twin all commercial pilots train in at some point is far more relevant as a demonstration of the prop drag of a light single (similar power per engine) than one of four large radials in a big aircraft.
You're not going to try to invoke rotor-wing flight again, are you?
Typical light aircraft have a much better glide ratio than he suggests, which is important to people who are planning flights, especially if there are areas where an engine failure would lead to a difficult landing - over water, woodland, mountains or other rough terrain. I have a friend who managed to glide just clear of the rough moorland hillside he had an engine failure over. Poor glide ration would have meant he could not have made the glide off the hills, and had he thought like that he would have concentrated on the wrong thing, minimising impact in a poor location, rather than achieving a safe landing in a good one.
Worked with a larger prop the force gets higher of course (because energy relates to velocity squared, momentum only to velocity, so the same energy produces less change of momentum if the speed change is higher. Force equates to rate of change of momentum), and with a helicopter rotor diameter much higher still, which is how it can fly.
That aside, your last paragraph makes no sense. Try it again.
How does one produce lift without power?
Have you ever flown an airplane?
Have you ever seen a sailplane? Ever flown one? Ever shut off the engine in a light airplane and glided for a while? Lift is still produced, even with no power. Even with no engine. Imagine that. Airplanes even go back up, even perform entire aerobatic routines with full control, and plenty of lift...all with no power. Does this dazzle your mind? It really shouldn't.
Power is required for autorotation, otherwise one could autorotate and remain level. I suggest you find a physics text book and look up the meaning of the word power. I can assure you it will talk about conversion of energy. Energy can be in the form of potential energy or in the form of chemical energy before its conversion, but power is by definition simply a rate of conversion of energy.
I really have to question if you have any experience or training or education in flying an airplane at all. You don't seem to have a clue what you're talking about. I'll help you out, and then I think it's time to dismiss you as a troll and move on. A helicopter under autorotation is operating with the transmission clutch disengaged; the rotor is not under engine power or the influence of engine power at all. When we speak of powered flight, we speak of various types of internal combustion engines (in most cases) producing power to drive a propeller or rotor, or to produce jet thrust. A helicopter descending in an autorotative state is not doing so under an engine driven rotor, and is not in a powered state. This appears to be a new concept to you, or perhaps you're just overly arguementative...but your arguements have left the realm of rational discussion, relevant discussion, and now you're talking stupidly.
The only exception to powered autorotative flight is the autogryo, or gyroplane, in which the aircraft operates continuously in an autorotative state under power, despite the fact that the rotor itself isn't powered. That's far afield from the original poster's question, and as he's already stated that he's received the answer he desired, I'll end my discussions with you now, and leave you to your ramblings.
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SN3
Ag planes are rarely if ever used in the countries where I fly most. I have no interest in ag flying. Why should I have heard of such a plane? Why does it have any relevance to private flying? What proportion of private pilots fly them?
There is one comment you make that proves you misunderstood all the relevant physics, therefore this is a bit of a pointless conversation. It is the response to my query about how to produce lift without power, by saying "airspeed".
Of course it is impossible to achieve any airspeed (above windspeed), or sustain airspeed against drag, without converting energy. Conversion of energy is power.
A sailplane uses the power in converting potential energy to kinetic energy to produce airflow and thus lift, and takes kinetic energy out of rising air to convert to potential energy and to kinetic energy in another direction. To a physicist that is still power. Power is just rate of conversion of energy. Without power a sailplane cannot fly.
I introduced the helicopter as an extreme example in the consideration of energy used to produce given thrust. The same power producing slower airflow has to move more air and will provide higher thrust. Large props produce low speeds of flow, and note that speed of airflow comes into all the calculations, so large props behave differently. It is standard physics, the same reason a high-bypass turbofan is more efficient than a turbojet. I was talking specifically about propellors, and in physical terms a rotor is a very large propellor, so it was relevant. It should be obvious that an R44 produces far more thrust from its 205 hp than an Arrow does from 200 hp, or the later would be able to hover on its prop.
Helicopters are also relevant if you start to make wild statements like "power doesn't achieve lift". It is a more direct example of power doing just that.
Note I never denied that a prop creates drag, but nor was I trying to make an accurate calculation, as the data are not easily available. In fact I pointed out that it always produces drag. However prop drag is related strongly to prop diameter as is thrust produced by a given power. That is why power of an aircraft with a large prop diameter and poor glide ratio is irrelevant to consideration of something like a PA28 or a 172, with a tiny prop which has a small, although measurable effect on glide ratio (or so I am told by someone who stopped it in the glide, cutting out 95% of prop drag, and made it a little further than otherwise, critically over the airfield fence).
You still haven't come up with any typical GA aircraft with a glide ratio less than 7:1. So what is the point of arguing the case for an ag plane that is irrelevant?
Ag planes are rarely if ever used in the countries where I fly most. I have no interest in ag flying. Why should I have heard of such a plane? Why does it have any relevance to private flying? What proportion of private pilots fly them?
There is one comment you make that proves you misunderstood all the relevant physics, therefore this is a bit of a pointless conversation. It is the response to my query about how to produce lift without power, by saying "airspeed".
Of course it is impossible to achieve any airspeed (above windspeed), or sustain airspeed against drag, without converting energy. Conversion of energy is power.
A sailplane uses the power in converting potential energy to kinetic energy to produce airflow and thus lift, and takes kinetic energy out of rising air to convert to potential energy and to kinetic energy in another direction. To a physicist that is still power. Power is just rate of conversion of energy. Without power a sailplane cannot fly.
I introduced the helicopter as an extreme example in the consideration of energy used to produce given thrust. The same power producing slower airflow has to move more air and will provide higher thrust. Large props produce low speeds of flow, and note that speed of airflow comes into all the calculations, so large props behave differently. It is standard physics, the same reason a high-bypass turbofan is more efficient than a turbojet. I was talking specifically about propellors, and in physical terms a rotor is a very large propellor, so it was relevant. It should be obvious that an R44 produces far more thrust from its 205 hp than an Arrow does from 200 hp, or the later would be able to hover on its prop.
Helicopters are also relevant if you start to make wild statements like "power doesn't achieve lift". It is a more direct example of power doing just that.
Note I never denied that a prop creates drag, but nor was I trying to make an accurate calculation, as the data are not easily available. In fact I pointed out that it always produces drag. However prop drag is related strongly to prop diameter as is thrust produced by a given power. That is why power of an aircraft with a large prop diameter and poor glide ratio is irrelevant to consideration of something like a PA28 or a 172, with a tiny prop which has a small, although measurable effect on glide ratio (or so I am told by someone who stopped it in the glide, cutting out 95% of prop drag, and made it a little further than otherwise, critically over the airfield fence).
You still haven't come up with any typical GA aircraft with a glide ratio less than 7:1. So what is the point of arguing the case for an ag plane that is irrelevant?
Last edited by Lost man standing; 30th Aug 2008 at 16:52.
Lange Aviation - Antares 20E - Intro
ASH 30 Mi
Both about 60:1 I believe.
And to the folks talking about a low aerotow launch failure, a low winch launch failure is also horribly entertaining for the few seconds it takes to get back on the ground.
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SNS3Guppy said:
I've come late to this discussion, so will merely observe that SNS3's observation is wildly inaccurate.
The vast majority of light aeroplanes actually have best-glide ratios in the range 9:1 to 12:1 (just over 10:1 in the case of my A36 Bonanza), although a small number of examples can be found either side of these boundaries. Modern jet airliners do somewhat better at >15:1, and high performance sailplanes can be up around 60:1.
Most light airplanes have a glide ration which approximates about a 6:1 ratio or so, though some as little as 3:1.
The vast majority of light aeroplanes actually have best-glide ratios in the range 9:1 to 12:1 (just over 10:1 in the case of my A36 Bonanza), although a small number of examples can be found either side of these boundaries. Modern jet airliners do somewhat better at >15:1, and high performance sailplanes can be up around 60:1.
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From my Beech C23 (Sundowner) POH:
"Glide distance is approximately 1.7 nautical miles per 1000 ft of altitude above the terrain".
Doing the math, that gives a 10.3:1 glide ratio.
Beech
"Glide distance is approximately 1.7 nautical miles per 1000 ft of altitude above the terrain".
Doing the math, that gives a 10.3:1 glide ratio.
Beech
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Glide ratio 747
Just to throw this into your discussion...
The glide ratio of a 747 is close to 18:1 -
My answer to those who say "a jetliner glides like a brick" -
My opinion - lightplanes glide like bricks.
xxx
Often played the game of IDLE descents from FL390 to 1000 ft AGL/MSL -
Gliding distance is generally 110/120 NM (no wind factor) -
xxx
Oh sure... I admit there is residual thrust of the 4 engines...
We do not shutdown the motors at TOD and relight at outer marker to impress you further.
xxx
Now ready to be accused of reckless flying -
Trouble is, among the many who practiced similar games were... chief pilots.
Yes yes, I know - with YOUR airline, you are professionals and do not indulge in such.
xxx
Happy contrails
The glide ratio of a 747 is close to 18:1 -
My answer to those who say "a jetliner glides like a brick" -
My opinion - lightplanes glide like bricks.
xxx
Often played the game of IDLE descents from FL390 to 1000 ft AGL/MSL -
Gliding distance is generally 110/120 NM (no wind factor) -
xxx
Oh sure... I admit there is residual thrust of the 4 engines...
We do not shutdown the motors at TOD and relight at outer marker to impress you further.
xxx
Now ready to be accused of reckless flying -
Trouble is, among the many who practiced similar games were... chief pilots.
Yes yes, I know - with YOUR airline, you are professionals and do not indulge in such.
xxx
Happy contrails
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In my experience (Math(s) aside), 10:1 is realistic for most light aeroplanes.
The main thing is that they normally don't drop like a brick. The pilot often messes up the emergency landing though, but that is another story. I see on the BBC website today (31.08) someone in Devon made a sucessful emergency landing into a marsh / boggy land or all places. Good one
The main thing is that they normally don't drop like a brick. The pilot often messes up the emergency landing though, but that is another story. I see on the BBC website today (31.08) someone in Devon made a sucessful emergency landing into a marsh / boggy land or all places. Good one
Not a Stemme S-10, although it's a good compromise between an aircraft capable of touring and an adequate performance glider. I offended an owner by suggesting after flying one that it was almost as good as having a glider................
Currently either the Eta or the Binder EB-28, both of which are self launching 2-seater sailplanes with a best glide (engine off and retracted) in excess of 60:1
EB28. The 28 is for wingspan in metres.
However, while that answers the original question,I don't think it's whet the thread starter meant.
Currently either the Eta or the Binder EB-28, both of which are self launching 2-seater sailplanes with a best glide (engine off and retracted) in excess of 60:1
EB28. The 28 is for wingspan in metres.
However, while that answers the original question,I don't think it's whet the thread starter meant.
Last edited by Fitter2; 31st Aug 2008 at 20:24.
I introduced the helicopter as an extreme example in the consideration of energy used to produce given thrust. The same power producing slower airflow has to move more air and will provide higher thrust.
We manage it in a turboprop engine at substantially slower speeds, but the RPM isn't relevant...the size of the prop and the design of the blades, as well as the angle of attack coupled with a greater torque capacity mean that more air can be moved. Light single engine piston propeller driven airpalnes have limited RPM ranges, limited propeller options, and are really no comparison to a helicopter...so introducing the helicopter is a ridiculous example.
Large props produce low speeds of flow, and note that speed of airflow comes into all the calculations, so large props behave differently. It is standard physics, the same reason a high-bypass turbofan is more efficient than a turbojet.
I was talking specifically about propellors, and in physical terms a rotor is a very large propellor, so it was relevant. It should be obvious that an R44 produces far more thrust from its 205 hp than an Arrow does from 200 hp, or the later would be able to hover on its prop.
You're simply confusing the topic with ridiculous comparisons...such as the introduction of a helicopter into a discussion of glides in a fixed wing airplane.
Helicopters are also relevant if you start to make wild statements like "power doesn't achieve lift". It is a more direct example of power doing just that.
A better comparison might be an autogyro with a propeller being driven by an engine, and a rotor producing lift in a state of autorotation. The difference between a state of auto-rotation and a driven rotor state is two-fold. The obvious difference is the motive force to turn the rotor, but the clear difference is the direction of airflow through the rotor plane.
Of course, you seem to have trouble understanding how the introduction of a light single engine piston powered general aviation airplane relates to a conversation involving light single engine piston powered general aviation airplanes...so it's no surprise that you're confused.
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Lost Man standing, my hat is off to you attempting to discuss flying with SNS3Guppy.
There was a time when I was tempted to but decided the effort was not worth it because it would not really change the way the world evolves, you see SNS3Guppy has done it all and none of us unwashed mortals know anything about flying.
This bit I clipped out says it all.
Quote:
SNS3Guppy said:
Quote:
Most light airplanes have a glide ration which approximates about a 6:1 ratio or so, though some as little as 3:1.
Quote from Islander2:
I've come late to this discussion, so will merely observe that SNS3's observation is wildly inaccurate.
For sure it is entertaining non the less.
There was a time when I was tempted to but decided the effort was not worth it because it would not really change the way the world evolves, you see SNS3Guppy has done it all and none of us unwashed mortals know anything about flying.
This bit I clipped out says it all.
Quote:
SNS3Guppy said:
Quote:
Most light airplanes have a glide ration which approximates about a 6:1 ratio or so, though some as little as 3:1.
Quote from Islander2:
I've come late to this discussion, so will merely observe that SNS3's observation is wildly inaccurate.
For sure it is entertaining non the less.
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Cheers Chuck.
It's fun though, and ever since school and my degree physics has been a kind of hobby with me, so it is interesting to go through the processes SN3's misunderstandings of basic physics force upon me.
SN3
Still no actual, relevant examples?
If you move more air (say by using a larger prop) with the same power then it moves more slowly than moving a small amount of air with the same power. However because there is more mass flow the thrust is actually higher. Thus the size of prop is critical in understanding the issue we are talking about (note that I never mentioned propellor speed at all. I am not sure where you got that from).
That is why the helicopter rotor is relevant. It is nothing to do with the forward component of lift causing the forward motion of as helicopter, that really is irrelevant and I have no idea why you brought it in. It is to do with how a large prop compares with a small prop in terms of producing thrust from a given power. A helicopter rotor moves a larger amount of air than an aircraft prop, at a lower speed given the same power. The helicopter is straight-forward proof of this. An R44 rotor can produce thrust greater than its own max all-up weight in order to hover using only 205 hp. An Arrow with only 5 hp less could not hover on its prop even with only a pilot on board and a small amount of fuel, when it would be lighter than the R44.
Just because you say it ain't so doesn't mean it isn't, or a lot of 777s with their nice high-bypass turbofans would have started crashing just as you said it!
I can prove it with a few equations if necessary, but it is rather irrelevant if you are unable to understand those equations. If you could understand them they should be irrelevant, if I give the following description.
Energy is 1/2mv^2 and momentum is mv. Power is rate of change of energy, and force is rate of change of momentum (thrust is a force). So take m to be the mass of air passing in a second, v its change of velocity, mv is then momentum change in a second, i.e thrust and 1/2mv^2 is energy conversion in a second, i.e. power.
So increasing the mass flow by a factor of x at the same power reduces the velocity by a factor √x. The thrust is proportional to the mass flow and velocity, so is multiplied by a factor of x/√x. This is √x. So at the same power, reducing the speed of the airflow increases the thrust, as I said in the first place! Double the mass flow you have 41% more static thrust.
How does a rotor achieve relative motion without power?
Autorotation requires power. The rotors require power to start moving and to overcome drag and friction in all its various forms. The power in autorotation is the conversion of potential to kinetic energy. It's still power, even if it doesn't involve chemical energy!
You really don't understand what power is, do you? I say again: power is the rate of conversion or transfer of energy. Nothing more, nothing less. It does not require machinery. It can come from the burning of fossil fuel, the falling of a weight or the differential heating of the Earth's surface. It's still power!
An autogyro is not a better example. I wanted a more direct example of motive, mechanical power (i.e. what you already accepted as power, as I didn't at the time feel the need to teach you basic physics) producing lift than a fixed-wing aircraft, which does it by producing thrust, which moves the aircraft, which causes airflow across the wing which then produces lift. The helicopter just uses power to movement of a wing that produces lift. You then come up with an autogyro, which does use power to produce lift but in an even more roundabout way than a fixed-wing aircraft!
Have you ever actually read the title of the forum? Do you know what "Private Flying" is? Have you noticed that there is a separate forum for "Biz Jets, Ag planes GA etc." flying, in which an answer including an ag plane might indeed have been relevant?
The matching number of engines and the power plant type are beside the point, as is the fact that it is a GA aircraft. The fact that it is not used for "Private Flying", the entire purpose of this forum, means it is irrelevant to the discussion.
It's fun though, and ever since school and my degree physics has been a kind of hobby with me, so it is interesting to go through the processes SN3's misunderstandings of basic physics force upon me.
SN3
Still no actual, relevant examples?
If you move more air (say by using a larger prop) with the same power then it moves more slowly than moving a small amount of air with the same power. However because there is more mass flow the thrust is actually higher. Thus the size of prop is critical in understanding the issue we are talking about (note that I never mentioned propellor speed at all. I am not sure where you got that from).
That is why the helicopter rotor is relevant. It is nothing to do with the forward component of lift causing the forward motion of as helicopter, that really is irrelevant and I have no idea why you brought it in. It is to do with how a large prop compares with a small prop in terms of producing thrust from a given power. A helicopter rotor moves a larger amount of air than an aircraft prop, at a lower speed given the same power. The helicopter is straight-forward proof of this. An R44 rotor can produce thrust greater than its own max all-up weight in order to hover using only 205 hp. An Arrow with only 5 hp less could not hover on its prop even with only a pilot on board and a small amount of fuel, when it would be lighter than the R44.
Just because you say it ain't so doesn't mean it isn't, or a lot of 777s with their nice high-bypass turbofans would have started crashing just as you said it!
I can prove it with a few equations if necessary, but it is rather irrelevant if you are unable to understand those equations. If you could understand them they should be irrelevant, if I give the following description.
Energy is 1/2mv^2 and momentum is mv. Power is rate of change of energy, and force is rate of change of momentum (thrust is a force). So take m to be the mass of air passing in a second, v its change of velocity, mv is then momentum change in a second, i.e thrust and 1/2mv^2 is energy conversion in a second, i.e. power.
So increasing the mass flow by a factor of x at the same power reduces the velocity by a factor √x. The thrust is proportional to the mass flow and velocity, so is multiplied by a factor of x/√x. This is √x. So at the same power, reducing the speed of the airflow increases the thrust, as I said in the first place! Double the mass flow you have 41% more static thrust.
Power does not achieve lift. In the case of a helicopter, you're confused between the relative motion of the rotor...which will turn with or without power (visit autorotation)
Autorotation requires power. The rotors require power to start moving and to overcome drag and friction in all its various forms. The power in autorotation is the conversion of potential to kinetic energy. It's still power, even if it doesn't involve chemical energy!
You really don't understand what power is, do you? I say again: power is the rate of conversion or transfer of energy. Nothing more, nothing less. It does not require machinery. It can come from the burning of fossil fuel, the falling of a weight or the differential heating of the Earth's surface. It's still power!
An autogyro is not a better example. I wanted a more direct example of motive, mechanical power (i.e. what you already accepted as power, as I didn't at the time feel the need to teach you basic physics) producing lift than a fixed-wing aircraft, which does it by producing thrust, which moves the aircraft, which causes airflow across the wing which then produces lift. The helicopter just uses power to movement of a wing that produces lift. You then come up with an autogyro, which does use power to produce lift but in an even more roundabout way than a fixed-wing aircraft!
Of course, you seem to have trouble understanding how the introduction of a light single engine piston powered general aviation airplane relates to a conversation involving light single engine piston powered general aviation airplanes...so it's no surprise that you're confused.
The matching number of engines and the power plant type are beside the point, as is the fact that it is a GA aircraft. The fact that it is not used for "Private Flying", the entire purpose of this forum, means it is irrelevant to the discussion.
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Lost man Standing, I am not anywhere near educated enough to understand the math behind the physics of flying as I am a mere pilot who was fortunate to have worked at many different types of flying during my career, SNS3Guppy has brought Ag Flying into the mix and it brought back fond memories of years long passed......
...seeing as this is a private pilot forum I am attaching a story I wrote about my first flying job.....if it bores people they can just skip it, if they like it then there was nothing lost by posting it.
************************************************************
The Tobacco Fields - By Chuck Ellsworth
For generations the farmers of southern Ontario have planted cared for harvested and cured tobacco in a small area on the northern shores of lake Erie. Our part in this very lucrative cash crop was aerial application of fertilizers and pesticides better known as crop dusting.
At the end of the twentieth century this form of farming is slowly dying due to the ever-increasing movement of the anti-smoking segment of society. Although few would argue the health risks of smoking it is interesting that our government actively supports both sides of this social problem. Several times in the past ten or so years I have rented a car and driven back to the tobacco farming area of Southern Ontario, where over forty years ago I was part of that unique group of pilots who earned their living flying the crop dusting planes.
The narrow old highways are still there, but like the tobacco farms they are slowly fading into history as newer and more modern freeways are built. The easiest way of finding tobacco country is to drive highway 3, during the nineteen forties and early fifties this winding narrow road was the main route from Windsor through the heart of tobacco country and on to the Niagara district. Soon after leaving the modern multi lane 401 to highway 3 you will begin to realize that although it was only a short drive you have drifted back a long way in time. Driving through the small villages and towns very little has changed and life seems to be as it was in the boom days of tobacco farming, when transients came from all over the continent for the harvest. They came by the hundreds to towns like Aylmer, Tillsonberg, Deli and Simcoe, these towns that were synonymous with tobacco have changed so little it is like going back in time.
Several of the airfields we flew our Cubs, Super Cubs and Stearmans out of in the fifties and early sixties are still there. Just outside of Simcoe highway 3 runs right past the airport and even before turning into the driveway to the field I can see that after all these years nothing seems to have changed. I could be in a time warp and can imagine a Stearman or Cub landing and one of my old flying friends getting out of his airplane after another morning killing tobacco horn worms, and saying come on Chuck lets walk down to the restaurant and have breakfast. The tobacco hornworm was a perennial pest and our most important and profitable source of income. Most of my old companion's names have faded from memory as the years have passed and we went our different ways but some of them are easy to recall.
Like Lorne Beacroft a really great cropduster and Stearman pilot. Lorne and I shared many exciting adventures in our airplanes working together from the row crop farms in Southern Ontario to conifer release spraying all over Northern Ontario for the big pulp and paper companies. Little did we know then that many years later I would pick up a newspaper thousands of miles away and read about Lorne being Canadas first successful heart transplant. I wonder where he is today and what he is doing?
There are others, Tom Martindale whom I talked to just last year after over forty years, now retired having flown a long career with Trans Canada Airlines, now named Air Canada. Then there was Howard Zimmerman who went on to run his own helicopter company and still in the aerial applicating business last I heard of him. And who could forget Bud Boughner another character that just disappeared probably still out there somewhere flying for someone.
I have been back to St. Thomas, another tobacco farming town on highway 3 twice in the last several years to pick up airplanes to move for people in my ferry business. The airport has changed very little over the years. The hangar where I first learned to fly cropdusters is still there with the same smell of chemicals that no Ag. Pilot can ever forget. It is now the home of Hicks and Lawrence who were in the business in the fifties and still at it, only the airplanes have changed.
My first flying job started in that hangar, right from a brand new commercial license to the greatest flying job that any pilot could ever want. There were twenty-three of us who started the crop dusting course early that spring, in the end only three were hired and I was fortunate to have been one of them.
With the grand total of 252 hours in my log book I started my training with an old duster pilot named George Walker. Right from the start he let me know that I was either going to fly this damned thing right on its limits and be absolutely perfect in flying crop spraying patterns or the training wouldn't last long. It was fantastic not only to learn how to really fly unusual attitudes but do it right at ground level.
To become a good crop duster pilot required that you accurately fly the airplane to evenly apply the chemicals over the field being treated. We really had to be careful with our flying when applying fertilizers in early spring as any error was there for all to see as the crop started growing. This was achieved by starting on one side of the field maintaining a constant height, airspeed and track over the crop. Just prior to reaching the end of your run full power was applied, and at the last moment the spray booms were shut off and at the same time a forty-five degree climb was initiated. As soon as you were clear of obstructions a turn right or left was made using forty five to sixty degrees of bank. After approximately three seconds a very quick turn in the opposite direction was entered until a complete one hundred and eighty degree change of direction had been completed. If done properly you were now lined up exactly forty-five feet right or left of the track you had just flown down the field.
From that point a forty-five degree dive was entered and with the use of power recovery to level flight was made at the exact height above the crop and the exact airspeed required for the next run down the field in the opposite direction to your last pass. Speed was maintained from that point by reducing power.
To finish the course and be one of the three finally hired was really hard to believe. To be paid to do this was beyond belief. When the season began we were each assigned an airplane, a crash helmet, a tent and sleeping bag and sent off to set up what was to be our summer home on some farmers field. Mine was near Langdon just a few miles from lake Erie.
Last year I tried without success to find the field where my Cub and I spent a lot of that first summer. Time and change linked with my memory of its location being from flying into it rather than driving to it worked against me and I was unable to find it. Remembering it however is easy, how could one forget crawling out of my tent just before sunrise to mix the chemicals? Then pump it into the spray tank and hand start the cub. Then to be in the air just as it was getting light enough to see safely and get in as many acres as possible before the wind came up and shut down our flying until evening. Then with luck the wind would go down enough to allow us to resume work before darkness would shut us down for the day. The company had a very good method for assuring we would spray the correct field.
Each new job was given to us by the salesman who after selling the farmer drew a map for the pilots with the location of the farm and each building and its color plus all the different crops were written on the map drawn to scale. As well as the buildings all trees, fences and power lines were drawn to scale. It was very easy for us to find and positively identify our field to be sprayed and I can not remember us making any errors in that regard.
Sadly there were to many flying errors made and during the first three years that I crop-dusted eight pilots died in this very demanding type of flying in our area. Most of the accidents were due to stalling in turns or hitting power lines, fences or trees.
One new pilot who had only been with us for two weeks died while doing a low level stall turn and spinning in, he was just to low to recover from the loss of control. He had been on his way back from a spraying mission when he decided to put on an airshow at the farm of his girlfriend of the moment. This particular accident was to be the last for a long time as those of us who were flying for the different companies in that area had by that time figured out what the limits were that we could not go beyond.
Even though there were a lot of accidents in the early years they at least gave the industry the motivation to keep improving on flying safety, which made a great difference in the frequency of pilot error accidents. Agricultural flying has improved in other areas as well especially in the use of toxic chemicals.
In 1961 Rachel Carson wrote a book called "The silent spring. " This book was the beginning of public awareness to the danger of the wide area spraying of chemicals especially the use of D.D.T. to control Mosquitoes and black flies.
For years all over the world we had been using this chemical not really aware that it had a very long-term residual life. When Rachels book pointed out that D.D.T. had began to build up in the food chain in nature, she also showed that as a result many of the birds and other species were in danger of being wiped out due to D.D.T. Her book became a best seller and we in the aerial application business were worried that it would drastically affect our business, and it did.
The government agency in Ontario that regulated pesticides and their use called a series of meetings with the industry. From these meetings new laws were passed requiring us to attend Guelph agricultural college and receive a diploma in toxicology and entomology. I attended these classes and in the spring of 1962 passed the exams and received Pest Control License Class 3 - Aerial Applicator.
My license number was 001. Now if nothing else I can say that I may not have been the best but I was the first. Without doubt the knowledge and understanding of the relationship of these chemicals to the environment more than made up for all the work that went into getting the license. From that point on the industry went to great length to find and use chemicals less toxic to our animal life and also to humans.
It would be easy to just keep right on writing about aerial application and all the exciting and sometimes boring experiences we had, however I will sum it all up with the observation that crop dusting was not only my first flying job it was without doubt the best. I flew seven seasons' crop dusting and I often think of someday giving it another go, at least for a short time.
...seeing as this is a private pilot forum I am attaching a story I wrote about my first flying job.....if it bores people they can just skip it, if they like it then there was nothing lost by posting it.
************************************************************
The Tobacco Fields - By Chuck Ellsworth
For generations the farmers of southern Ontario have planted cared for harvested and cured tobacco in a small area on the northern shores of lake Erie. Our part in this very lucrative cash crop was aerial application of fertilizers and pesticides better known as crop dusting.
At the end of the twentieth century this form of farming is slowly dying due to the ever-increasing movement of the anti-smoking segment of society. Although few would argue the health risks of smoking it is interesting that our government actively supports both sides of this social problem. Several times in the past ten or so years I have rented a car and driven back to the tobacco farming area of Southern Ontario, where over forty years ago I was part of that unique group of pilots who earned their living flying the crop dusting planes.
The narrow old highways are still there, but like the tobacco farms they are slowly fading into history as newer and more modern freeways are built. The easiest way of finding tobacco country is to drive highway 3, during the nineteen forties and early fifties this winding narrow road was the main route from Windsor through the heart of tobacco country and on to the Niagara district. Soon after leaving the modern multi lane 401 to highway 3 you will begin to realize that although it was only a short drive you have drifted back a long way in time. Driving through the small villages and towns very little has changed and life seems to be as it was in the boom days of tobacco farming, when transients came from all over the continent for the harvest. They came by the hundreds to towns like Aylmer, Tillsonberg, Deli and Simcoe, these towns that were synonymous with tobacco have changed so little it is like going back in time.
Several of the airfields we flew our Cubs, Super Cubs and Stearmans out of in the fifties and early sixties are still there. Just outside of Simcoe highway 3 runs right past the airport and even before turning into the driveway to the field I can see that after all these years nothing seems to have changed. I could be in a time warp and can imagine a Stearman or Cub landing and one of my old flying friends getting out of his airplane after another morning killing tobacco horn worms, and saying come on Chuck lets walk down to the restaurant and have breakfast. The tobacco hornworm was a perennial pest and our most important and profitable source of income. Most of my old companion's names have faded from memory as the years have passed and we went our different ways but some of them are easy to recall.
Like Lorne Beacroft a really great cropduster and Stearman pilot. Lorne and I shared many exciting adventures in our airplanes working together from the row crop farms in Southern Ontario to conifer release spraying all over Northern Ontario for the big pulp and paper companies. Little did we know then that many years later I would pick up a newspaper thousands of miles away and read about Lorne being Canadas first successful heart transplant. I wonder where he is today and what he is doing?
There are others, Tom Martindale whom I talked to just last year after over forty years, now retired having flown a long career with Trans Canada Airlines, now named Air Canada. Then there was Howard Zimmerman who went on to run his own helicopter company and still in the aerial applicating business last I heard of him. And who could forget Bud Boughner another character that just disappeared probably still out there somewhere flying for someone.
I have been back to St. Thomas, another tobacco farming town on highway 3 twice in the last several years to pick up airplanes to move for people in my ferry business. The airport has changed very little over the years. The hangar where I first learned to fly cropdusters is still there with the same smell of chemicals that no Ag. Pilot can ever forget. It is now the home of Hicks and Lawrence who were in the business in the fifties and still at it, only the airplanes have changed.
My first flying job started in that hangar, right from a brand new commercial license to the greatest flying job that any pilot could ever want. There were twenty-three of us who started the crop dusting course early that spring, in the end only three were hired and I was fortunate to have been one of them.
With the grand total of 252 hours in my log book I started my training with an old duster pilot named George Walker. Right from the start he let me know that I was either going to fly this damned thing right on its limits and be absolutely perfect in flying crop spraying patterns or the training wouldn't last long. It was fantastic not only to learn how to really fly unusual attitudes but do it right at ground level.
To become a good crop duster pilot required that you accurately fly the airplane to evenly apply the chemicals over the field being treated. We really had to be careful with our flying when applying fertilizers in early spring as any error was there for all to see as the crop started growing. This was achieved by starting on one side of the field maintaining a constant height, airspeed and track over the crop. Just prior to reaching the end of your run full power was applied, and at the last moment the spray booms were shut off and at the same time a forty-five degree climb was initiated. As soon as you were clear of obstructions a turn right or left was made using forty five to sixty degrees of bank. After approximately three seconds a very quick turn in the opposite direction was entered until a complete one hundred and eighty degree change of direction had been completed. If done properly you were now lined up exactly forty-five feet right or left of the track you had just flown down the field.
From that point a forty-five degree dive was entered and with the use of power recovery to level flight was made at the exact height above the crop and the exact airspeed required for the next run down the field in the opposite direction to your last pass. Speed was maintained from that point by reducing power.
To finish the course and be one of the three finally hired was really hard to believe. To be paid to do this was beyond belief. When the season began we were each assigned an airplane, a crash helmet, a tent and sleeping bag and sent off to set up what was to be our summer home on some farmers field. Mine was near Langdon just a few miles from lake Erie.
Last year I tried without success to find the field where my Cub and I spent a lot of that first summer. Time and change linked with my memory of its location being from flying into it rather than driving to it worked against me and I was unable to find it. Remembering it however is easy, how could one forget crawling out of my tent just before sunrise to mix the chemicals? Then pump it into the spray tank and hand start the cub. Then to be in the air just as it was getting light enough to see safely and get in as many acres as possible before the wind came up and shut down our flying until evening. Then with luck the wind would go down enough to allow us to resume work before darkness would shut us down for the day. The company had a very good method for assuring we would spray the correct field.
Each new job was given to us by the salesman who after selling the farmer drew a map for the pilots with the location of the farm and each building and its color plus all the different crops were written on the map drawn to scale. As well as the buildings all trees, fences and power lines were drawn to scale. It was very easy for us to find and positively identify our field to be sprayed and I can not remember us making any errors in that regard.
Sadly there were to many flying errors made and during the first three years that I crop-dusted eight pilots died in this very demanding type of flying in our area. Most of the accidents were due to stalling in turns or hitting power lines, fences or trees.
One new pilot who had only been with us for two weeks died while doing a low level stall turn and spinning in, he was just to low to recover from the loss of control. He had been on his way back from a spraying mission when he decided to put on an airshow at the farm of his girlfriend of the moment. This particular accident was to be the last for a long time as those of us who were flying for the different companies in that area had by that time figured out what the limits were that we could not go beyond.
Even though there were a lot of accidents in the early years they at least gave the industry the motivation to keep improving on flying safety, which made a great difference in the frequency of pilot error accidents. Agricultural flying has improved in other areas as well especially in the use of toxic chemicals.
In 1961 Rachel Carson wrote a book called "The silent spring. " This book was the beginning of public awareness to the danger of the wide area spraying of chemicals especially the use of D.D.T. to control Mosquitoes and black flies.
For years all over the world we had been using this chemical not really aware that it had a very long-term residual life. When Rachels book pointed out that D.D.T. had began to build up in the food chain in nature, she also showed that as a result many of the birds and other species were in danger of being wiped out due to D.D.T. Her book became a best seller and we in the aerial application business were worried that it would drastically affect our business, and it did.
The government agency in Ontario that regulated pesticides and their use called a series of meetings with the industry. From these meetings new laws were passed requiring us to attend Guelph agricultural college and receive a diploma in toxicology and entomology. I attended these classes and in the spring of 1962 passed the exams and received Pest Control License Class 3 - Aerial Applicator.
My license number was 001. Now if nothing else I can say that I may not have been the best but I was the first. Without doubt the knowledge and understanding of the relationship of these chemicals to the environment more than made up for all the work that went into getting the license. From that point on the industry went to great length to find and use chemicals less toxic to our animal life and also to humans.
It would be easy to just keep right on writing about aerial application and all the exciting and sometimes boring experiences we had, however I will sum it all up with the observation that crop dusting was not only my first flying job it was without doubt the best. I flew seven seasons' crop dusting and I often think of someday giving it another go, at least for a short time.
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best engined glider
OK, so I had the pleasure of flying a Stemme S10 recently, what a joy, a ratio of 50-1, side by side seating and an engine that can push you along at
100 mph. A great aircraft, but, at what a cost, over £150000. So if you cant afford that try popping over to Enstone (Chipping Norton)and try out their lovely Super Dimona, it has an excellent glide ratio, so if the engine fails you should have enough time to sort out a suitable landing zone. It has great air brakes which make it reasonably easy to get into most fields.
100 mph. A great aircraft, but, at what a cost, over £150000. So if you cant afford that try popping over to Enstone (Chipping Norton)and try out their lovely Super Dimona, it has an excellent glide ratio, so if the engine fails you should have enough time to sort out a suitable landing zone. It has great air brakes which make it reasonably easy to get into most fields.