The Wizwheel, time to say good bye?
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The Wizwheel, time to say good bye?
Some bad points:
1.) Extremely difficult to use in the air, when work load is high.
2.) Navigation side impossible to use without a pencil (and pencils do like getting lost)
3.) Incredibly difficult to learn for new generation of (computer savvy) students who have never seen anything so archaic.
4.) Innaccurate.
5.) Too big in some cases.
Things I've often heard:
1.) The navigation side helps you to "see the triangle problem much more clearly" - So do some electronic devices.
2.) It's the only thing that can help you when your batteries run out or the electronic computer stops working - I can buy an additional battery, I can buy two electronic computers. I've never had an electronic handheld device fail on me. Ever.
3.) An electronic flight computer makes you lazy - It does not make you lazy, it reduces the work load which is key to safety and learning other aspects of flying.
The wizwheel (analogue flight computer) is an outdated, over rated navigation/calculation tool which is only used these days due to cob wridden oldies not understanding the benefit/ease of use of newer electronic devices.
Discuss.
(Sorry didn't mean to be rude, just extemely passionate about this subject. Thanks
)
1.) Extremely difficult to use in the air, when work load is high.
2.) Navigation side impossible to use without a pencil (and pencils do like getting lost)
3.) Incredibly difficult to learn for new generation of (computer savvy) students who have never seen anything so archaic.
4.) Innaccurate.
5.) Too big in some cases.
Things I've often heard:
1.) The navigation side helps you to "see the triangle problem much more clearly" - So do some electronic devices.
2.) It's the only thing that can help you when your batteries run out or the electronic computer stops working - I can buy an additional battery, I can buy two electronic computers. I've never had an electronic handheld device fail on me. Ever.
3.) An electronic flight computer makes you lazy - It does not make you lazy, it reduces the work load which is key to safety and learning other aspects of flying.
The wizwheel (analogue flight computer) is an outdated, over rated navigation/calculation tool which is only used these days due to cob wridden oldies not understanding the benefit/ease of use of newer electronic devices.
Discuss.
(Sorry didn't mean to be rude, just extemely passionate about this subject. Thanks
)
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Originally Posted by Superpilot
Some bad points:
1.) Extremely difficult to use in the air, when work load is high.
2.) Navigation side impossible to use without a pencil (and pencils do like getting lost)
3.) Incredibly difficult to learn for new generation of (computer savvy) students who have never seen anything so archaic.
4.) Innaccurate.
5.) Too big in some cases.
1.) Extremely difficult to use in the air, when work load is high.
2.) Navigation side impossible to use without a pencil (and pencils do like getting lost)
3.) Incredibly difficult to learn for new generation of (computer savvy) students who have never seen anything so archaic.
4.) Innaccurate.
5.) Too big in some cases.
2. Not the case at all. I use the Jeppesen circular CRPs and they do not need a pencil mark. It does help though. Yes pencils and pens get lost but if you can't draw a line on your map then you are probably not going to need the CRP anyway.
You will need to draw a line on your map for an unplanned diversion as well as noting down various times, frequencies etc enroute so the lack of any writing device at planning stage does not bode well for the navigation exercise.
3. Easy to use and easy to learn if not too lazy and the instructor knows what they are talking about. Practice is all that is required.
4. Is easily accurate to +/- 2 degrees. You can not fly as accurate as that and the metoffice can not predict the winds as accurate as that.
5. Get yourself a small one. The Jeppesen circular CRPs come in various sizes and the smaller one fits in the plam of your hand.
With practice, one can complete the drift and groundspeed calculations in your head. That also requires practice and it not for the lazy.
Regards,
DFC
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Ah, the old CRP-5. Completely invalueable for the Gen Nav ATPL exam, completely useless afterwards. It's an archaic throwback to the olden days when pilots where called aviators, had fantastic moustaches, smoked pipes and referred to their aircraft as crates.
draw a line on your chart, work out your max drift, then apply the clock code to work out how much drift you need to offset. work out your groundspeed and bingo, flight planning complete. no faffing about with some overpriced piece of plastic. and as for electronic calculators, they are even worse. anything that has an instruction manual greater than 4 pages is not going to make your life any easier.
draw a line on your chart, work out your max drift, then apply the clock code to work out how much drift you need to offset. work out your groundspeed and bingo, flight planning complete. no faffing about with some overpriced piece of plastic. and as for electronic calculators, they are even worse. anything that has an instruction manual greater than 4 pages is not going to make your life any easier.
Except that most people then fail to calculate their groundspeed properly from MDR - and cannot then work out the time at fixes accordingly.
MDR is excellent for unplanned diversions. But it is emphatically not an acceptable substitute for proper pre-flight planning. Whether you use a Dalton, an electronic calculator or an on-line method is immaterial. But the flight does require proper planning.
Incidentally, putting the groundpseed against the '60', then reading off time at waypoint distances along a leg is a classic example of the advantage of analogue versus digital computation in some circumstances.
Now waggle your ears and do some bunnyhops!
MDR is excellent for unplanned diversions. But it is emphatically not an acceptable substitute for proper pre-flight planning. Whether you use a Dalton, an electronic calculator or an on-line method is immaterial. But the flight does require proper planning.
Incidentally, putting the groundpseed against the '60', then reading off time at waypoint distances along a leg is a classic example of the advantage of analogue versus digital computation in some circumstances.
Now waggle your ears and do some bunnyhops!
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au contraire
in my humble opinion, using the max drift method is proper planning. you have assessed your flight and corrected for the wind. if people make mistakes, then it is down to unfamiliarity and a lack of practice, not indicative of the method being flawed. if you use familiar, you will find using it for real in flight will be doddle.
if you are not convinced with the method, try a few examples, they are within a degree or two and a few knots of groundspeed. close enough for the accuracy of your average PPL student and wind forecast by our friends in bracknell (or is it exeter).
batteries run out on electronic calcs, people lose whizzwheels, but you can't forget your brain. although some students do try and prove me wrong.
and you only get bunnyhops if it's your birthday!
in my humble opinion, using the max drift method is proper planning. you have assessed your flight and corrected for the wind. if people make mistakes, then it is down to unfamiliarity and a lack of practice, not indicative of the method being flawed. if you use familiar, you will find using it for real in flight will be doddle.
if you are not convinced with the method, try a few examples, they are within a degree or two and a few knots of groundspeed. close enough for the accuracy of your average PPL student and wind forecast by our friends in bracknell (or is it exeter).
batteries run out on electronic calcs, people lose whizzwheels, but you can't forget your brain. although some students do try and prove me wrong.
and you only get bunnyhops if it's your birthday!
Why do it if it's not fun?
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I assume we are talking about real-world flying, rather than training?
If that's the case, the first thing to point out is that the majority of real-world flying is done using some form of nav-aid (ground based or satelite). In this case, only a very rought idea of wind is needed, since the navaids can be used to ensure the correct track during flight.
Real world flying over reasonable distances without navaids, though, definitely requires proper planning. Doesn't really matter what method is used, but I can't see any problem with the whiz-wheel, for the reasons DFC gives. Likewise, I can't see any real problem with electronic planning tools. Once you've learnt to use it properly, I don't think the whiz-wheel is necessarily any more difficult to use.
FFF
---------------
If that's the case, the first thing to point out is that the majority of real-world flying is done using some form of nav-aid (ground based or satelite). In this case, only a very rought idea of wind is needed, since the navaids can be used to ensure the correct track during flight.
Real world flying over reasonable distances without navaids, though, definitely requires proper planning. Doesn't really matter what method is used, but I can't see any problem with the whiz-wheel, for the reasons DFC gives. Likewise, I can't see any real problem with electronic planning tools. Once you've learnt to use it properly, I don't think the whiz-wheel is necessarily any more difficult to use.
FFF
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Replying to the points made by Superpilot
1)Difficult to use in the air. Yes. Answer. Make the triangle of velocities simpler, by only using the information relevant to the particular plane you’re flying in and making it bigger and clearer. See my solution at Navok.co.uk.
2) No pencils are used for any calculation but I consider that pencil and paper are essential items.
Where you were and when you were there is the most important information you can acquire.
What sort of information or calculation do you want to do in the air? Just do a thorough preflight plan and it’ll all be in the notes. Won’t it?
No. It’s that annoying stuff called wind. It doesn’t always do what it’s supposed to do, and quite often, all the times and headings have to be re-adjusted as the flight proceeds. Using my device I can get an up- to-date wind vector in 2-3 seconds and then use MDR(mental dead reckoning) to get the time and heading for the next leg of the course. The times of pinpoints are logged. I know the distance between them and that gives me the ground speed and I note the average WCA and in 2-3 secs I’ve got the latest wind vector.
This updating is not of much value for local bimbles but I have found it invaluable on longer flights of 50-400mls. A change of wind strength and direction gives an early warning of change in weather or acts as a confirmation to the suspicion that a new set of conditions is on the way.
Calculation of heading and groundspeed is amenable to mental calculation via the 1:60 rule, but there is no reasonably accurate method of calculating the wind strength and direction. It can be inferred from headwind and crosswind components, but tangents are not amenable to mental calculation in the way that sines and the 1:60 rule is. A graphic model is easy,quick and accurate.
3)Incredibly difficult to learn for those reared in the computer age—and the decimal system and a generation or two, let down by poor quality teaching. Generations that did not have the essential template of fractions, multiplication tables, and the tricks of mental arithmetic burned into their brains at an early age. That’s the price you pay for making learning fun.
I like the “archaic” observation. The idea presumably is that because it is old it is valueless. It is not. It’s an ingenious bit of kit that provides so much information in a small space, but you need to know a bit about numbers and have some knowledge and appreciation of the use of logarithms, otherwise mistakes can be made. The chances of that are much reduced if you have the ability to anticipate the answer. The design of the machine is such that it assumes that the user is already well-practised in mental arithmetic. Those who are deficient in this respect, are forced to think in a different way and become resentful and return to their comfort zone of digital electronic gadgetry. Which incidentally I find uncomfortable, feeling much more at ease in the analogue world where geometry and numbers are combined. The retention of analogue displays on watches and cockpit instrumentation displays suggests that I am not alone in this.
And it’s not that old. It’s only about seventy years old and nothing else was there to take it’s place until the mid-eighties.
4) Inaccurate.
We are presumably talking about aircraft navigation and not guiding Voyager Two past Neptune by a hairsbreadth(in astronomical terms). Great accuracy is not a requirement and never has been. If anything, a reasonable criticism of the wind side of the instrument is that it is too accurate. 5 degree divisions round the compass would be fine, the individual degrees just add to the clutter.
5) Too big. Yes it’s not readily pocketable. I wouldn’t take one with me on the aircraft. I’d just use it for pre-flight planning. So it’s size doesn’t matter.
Taking your other points:-
1)The wind side helps you see the triangle more clearly. I don’t think so. It’s too cluttered and the scale is too small. Fine for the pre-flight on the ground, but too small for serious use in the air, especially in turbulence. Compare that clutter with the Navok design. The triangle of velocities is in your face, in colour, that guides the eye to the correct places.
2) You make a good point about the reliability of electronics. By and large my experience too. But one or two points. The displays have to be improved and more thought given to the size and number of buttons/switches, waterproofing and the provision of a facility to guard or lock the controls. Greater protection by way of design for use outdoors rather than an office environment would be highly desirable. A recall of the input figures, like a printout calculator, would be another good feature.
3) Flight computers make you lazy. Yes they do. Well they make me lazy. That is why I do all my calculations by mental arithmetic. If you don’t use it you lose it. Not only that but the more you practice the faster you get. So much so that I could get the figures for a flight in the time it takes you to go to your flight bag and get your calculator out.
Re-the thing being outdated and much beloved by oldies that don’t know about the ease of use etc of electronics.
That may be true to a degree but it is only fairly recently that electronics have become so reliable and cheap. Prior to the late eighties such devices were very, very expensive, heavy and bulky and unreliable. The old codgers were right not to place too much reliance on the new-fangled devices and often had to revert to the old techniques in the event of frequent failures and encounters with new, little-understood phenomena. We stand on the backs of those who have gone before. A little respect is in order.
When I was a boy in the fifties, the radio or wireless was a major item of furniture, the size of a fridge, that dominated the living room and took five minutes to warm up. Now, I believe you could get instant reception from one that could be fitted into a wrist watch.
Electronics do a lot but not everything. Take your GPS. Nothing affects a flight more than the wind, yet it doesn’t give you a wind vector as it doesn’t know the orientation of the aircraft’s axis. You have to go to the E6b page and input the heading and it will give you the wind vector. Mine doesn’t remember this , neither can it apply it to the rest of the route. All times given for the rest of the route are based on the current groundspeed. How daft is that?
Every pilot has to know the elements of navigation as a fall back and to check that everything is working as it should. We’re almost there, but not quite at the stage where lives or multi-million pound investments can be entrusted to electronics. Until then you’ll just have to get to grips with the maths and geometry of navigation, with the whiz-wheel being employed as a teaching aid. Get that information into your personal, portable computer--- the brain. If it(your brain) has an opinion it can criticise the output of the instrumentation. If it doesn’t have an opinion it is a slave to the instrumentation.
Whether the whiz wheel is the best aid in teaching the maths and geometry of navigation is perhaps open to question but the triangle of velocities, speed, time and distance have to be thoroughly understood. The current electronics may be easy to use and give (unnecessarily) accurate results, but they do not give understanding. I think that has been the reason why the whiz-wheel has not been dropped.
1)Difficult to use in the air. Yes. Answer. Make the triangle of velocities simpler, by only using the information relevant to the particular plane you’re flying in and making it bigger and clearer. See my solution at Navok.co.uk.
2) No pencils are used for any calculation but I consider that pencil and paper are essential items.
Where you were and when you were there is the most important information you can acquire.
What sort of information or calculation do you want to do in the air? Just do a thorough preflight plan and it’ll all be in the notes. Won’t it?
No. It’s that annoying stuff called wind. It doesn’t always do what it’s supposed to do, and quite often, all the times and headings have to be re-adjusted as the flight proceeds. Using my device I can get an up- to-date wind vector in 2-3 seconds and then use MDR(mental dead reckoning) to get the time and heading for the next leg of the course. The times of pinpoints are logged. I know the distance between them and that gives me the ground speed and I note the average WCA and in 2-3 secs I’ve got the latest wind vector.
This updating is not of much value for local bimbles but I have found it invaluable on longer flights of 50-400mls. A change of wind strength and direction gives an early warning of change in weather or acts as a confirmation to the suspicion that a new set of conditions is on the way.
Calculation of heading and groundspeed is amenable to mental calculation via the 1:60 rule, but there is no reasonably accurate method of calculating the wind strength and direction. It can be inferred from headwind and crosswind components, but tangents are not amenable to mental calculation in the way that sines and the 1:60 rule is. A graphic model is easy,quick and accurate.
3)Incredibly difficult to learn for those reared in the computer age—and the decimal system and a generation or two, let down by poor quality teaching. Generations that did not have the essential template of fractions, multiplication tables, and the tricks of mental arithmetic burned into their brains at an early age. That’s the price you pay for making learning fun.
I like the “archaic” observation. The idea presumably is that because it is old it is valueless. It is not. It’s an ingenious bit of kit that provides so much information in a small space, but you need to know a bit about numbers and have some knowledge and appreciation of the use of logarithms, otherwise mistakes can be made. The chances of that are much reduced if you have the ability to anticipate the answer. The design of the machine is such that it assumes that the user is already well-practised in mental arithmetic. Those who are deficient in this respect, are forced to think in a different way and become resentful and return to their comfort zone of digital electronic gadgetry. Which incidentally I find uncomfortable, feeling much more at ease in the analogue world where geometry and numbers are combined. The retention of analogue displays on watches and cockpit instrumentation displays suggests that I am not alone in this.
And it’s not that old. It’s only about seventy years old and nothing else was there to take it’s place until the mid-eighties.
4) Inaccurate.
We are presumably talking about aircraft navigation and not guiding Voyager Two past Neptune by a hairsbreadth(in astronomical terms). Great accuracy is not a requirement and never has been. If anything, a reasonable criticism of the wind side of the instrument is that it is too accurate. 5 degree divisions round the compass would be fine, the individual degrees just add to the clutter.
5) Too big. Yes it’s not readily pocketable. I wouldn’t take one with me on the aircraft. I’d just use it for pre-flight planning. So it’s size doesn’t matter.
Taking your other points:-
1)The wind side helps you see the triangle more clearly. I don’t think so. It’s too cluttered and the scale is too small. Fine for the pre-flight on the ground, but too small for serious use in the air, especially in turbulence. Compare that clutter with the Navok design. The triangle of velocities is in your face, in colour, that guides the eye to the correct places.
2) You make a good point about the reliability of electronics. By and large my experience too. But one or two points. The displays have to be improved and more thought given to the size and number of buttons/switches, waterproofing and the provision of a facility to guard or lock the controls. Greater protection by way of design for use outdoors rather than an office environment would be highly desirable. A recall of the input figures, like a printout calculator, would be another good feature.
3) Flight computers make you lazy. Yes they do. Well they make me lazy. That is why I do all my calculations by mental arithmetic. If you don’t use it you lose it. Not only that but the more you practice the faster you get. So much so that I could get the figures for a flight in the time it takes you to go to your flight bag and get your calculator out.
Re-the thing being outdated and much beloved by oldies that don’t know about the ease of use etc of electronics.
That may be true to a degree but it is only fairly recently that electronics have become so reliable and cheap. Prior to the late eighties such devices were very, very expensive, heavy and bulky and unreliable. The old codgers were right not to place too much reliance on the new-fangled devices and often had to revert to the old techniques in the event of frequent failures and encounters with new, little-understood phenomena. We stand on the backs of those who have gone before. A little respect is in order.
When I was a boy in the fifties, the radio or wireless was a major item of furniture, the size of a fridge, that dominated the living room and took five minutes to warm up. Now, I believe you could get instant reception from one that could be fitted into a wrist watch.
Electronics do a lot but not everything. Take your GPS. Nothing affects a flight more than the wind, yet it doesn’t give you a wind vector as it doesn’t know the orientation of the aircraft’s axis. You have to go to the E6b page and input the heading and it will give you the wind vector. Mine doesn’t remember this , neither can it apply it to the rest of the route. All times given for the rest of the route are based on the current groundspeed. How daft is that?
Every pilot has to know the elements of navigation as a fall back and to check that everything is working as it should. We’re almost there, but not quite at the stage where lives or multi-million pound investments can be entrusted to electronics. Until then you’ll just have to get to grips with the maths and geometry of navigation, with the whiz-wheel being employed as a teaching aid. Get that information into your personal, portable computer--- the brain. If it(your brain) has an opinion it can criticise the output of the instrumentation. If it doesn’t have an opinion it is a slave to the instrumentation.
Whether the whiz wheel is the best aid in teaching the maths and geometry of navigation is perhaps open to question but the triangle of velocities, speed, time and distance have to be thoroughly understood. The current electronics may be easy to use and give (unnecessarily) accurate results, but they do not give understanding. I think that has been the reason why the whiz-wheel has not been dropped.
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Agree with DFC:
Had one for over 20 years (same one) - does the wind & ground speed etc in the same way as the Max Drift and Clock method - just much more accurately. I can do the calcs using one hand too once I've got the wind dot done. Totally magic and it never fails to amuse/impress the studes!
5. Get yourself a small one. The Jeppesen circular CRPs come in various sizes and the smaller one fits in the palm of your hand.
2.) It's the only thing that can help you when your batteries run out or the electronic computer stops working - I can buy an additional battery, I can buy two electronic computers. I've never had an electronic handheld device fail on me. Ever.
Dont put to much trust in your little handheld device, electric or otherwise.
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I do the drift bit in my head but have used the back of the CRP for years and it has served me well. Fuel, TAS when in airways in smaller aircraft, conversions etc. I am not a dinosaur, I just find it much easier to use than an electronic navcomputer. It becomes easy with regular use.
Gus - is the smile on your face caused by where Fern has had her hand?
Max drift is fine for heading calculations, but it is much more difficult to use for groundspeed calculation. Let's say that at 2000 ft and ISA, the wind is 50 deg off at 20 kts, that means a headwind component of 2/3 x 20 = 13 and a bit, call it 15 kts. If your IAS is 90, then that's a GS of 75. Now, the first fix on track is after 21 miles, so that'll take (21/75) x 60 = err, umm .....well, at 90 it would have taken 2/3 of 21 which is 14 minutes and we're doing 5/6 of 90 so it'll take, err..6/5 of 14 which is 12/10 x 14, so that's 120 plus 48 divided by 10 = 16.8 minutes.
Fine - but what a faff pre-flight. Yes, clever folks can do it, but why bother? It's within a minute of the correct value - but it seems more trouble than its worth to me!
Now can Gus please turn out the lights?
Max drift is fine for heading calculations, but it is much more difficult to use for groundspeed calculation. Let's say that at 2000 ft and ISA, the wind is 50 deg off at 20 kts, that means a headwind component of 2/3 x 20 = 13 and a bit, call it 15 kts. If your IAS is 90, then that's a GS of 75. Now, the first fix on track is after 21 miles, so that'll take (21/75) x 60 = err, umm .....well, at 90 it would have taken 2/3 of 21 which is 14 minutes and we're doing 5/6 of 90 so it'll take, err..6/5 of 14 which is 12/10 x 14, so that's 120 plus 48 divided by 10 = 16.8 minutes.
Fine - but what a faff pre-flight. Yes, clever folks can do it, but why bother? It's within a minute of the correct value - but it seems more trouble than its worth to me!
Now can Gus please turn out the lights?
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BEagle,
If the groundspeed is 60 knots then 21nm will take 21 minutes.
If the groundspeed is 70 knots then it will take 6/7 of the time i.e. 18 minutes
If the groundspeed is 80 knots then it will take 6/8 (3/4) of the time.
If it is 75 knots then it is half way between.
Regards,
DFC
If the groundspeed is 60 knots then 21nm will take 21 minutes.
If the groundspeed is 70 knots then it will take 6/7 of the time i.e. 18 minutes
If the groundspeed is 80 knots then it will take 6/8 (3/4) of the time.
If it is 75 knots then it is half way between.
Regards,
DFC
So working out a rough estimate twice and averaging the result is the way to go, huh?
OK - this time the GS is 83 KIAS. Work it out at 90, then at 80, then add a third of the difference to the 80 KIAS figure?
Still a stupid amount of work, compared to doing it accurately once!
OK - this time the GS is 83 KIAS. Work it out at 90, then at 80, then add a third of the difference to the 80 KIAS figure?
Still a stupid amount of work, compared to doing it accurately once!
Err, the simple way is surely to work out the still air times then change them by whatever percentage the head/tail wind is of your TAS.
TAS 90kts = 2/3nm/min so 15 miles = 10 mins
HWC = 12 kts so about 13% increase on still air time, = 11.3 mins
Or if you prefer, just use 10% of g/s in 6 mins. GS=75kts gives 7.5nm in 6 minutes. 21nm is just less than 3 lots of 6 minutes.
Personally I like using the DI to solve all my drift and H/TWC sums "on the fly" - just look at it, find the wind and use ratios to do the MDR assessments - trivially simple, totally accurate, no gadgets needed and no maths.
HFD
TAS 90kts = 2/3nm/min so 15 miles = 10 mins
HWC = 12 kts so about 13% increase on still air time, = 11.3 mins
Or if you prefer, just use 10% of g/s in 6 mins. GS=75kts gives 7.5nm in 6 minutes. 21nm is just less than 3 lots of 6 minutes.
Personally I like using the DI to solve all my drift and H/TWC sums "on the fly" - just look at it, find the wind and use ratios to do the MDR assessments - trivially simple, totally accurate, no gadgets needed and no maths.
HFD
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Or you could try this:- “Factor” for 75kts is 0.8(time taken in minutes to complete 1nml)
The factors for each groundspeed are printed on the Airspeed /Groundspeed plate of the NavOK equipment.
21×0.8=21-21×0.2=21-4.2=21-4=17-0.2=16.8mins. But the windspeed was overestimated therefore the groundspeed is a little faster than 75kts. 16-16.5 mins will do me. I’ll be looking out for the target at 10-12mins.
The factors for each groundspeed are printed on the Airspeed /Groundspeed plate of the NavOK equipment.
21×0.8=21-21×0.2=21-4.2=21-4=17-0.2=16.8mins. But the windspeed was overestimated therefore the groundspeed is a little faster than 75kts. 16-16.5 mins will do me. I’ll be looking out for the target at 10-12mins.
I advocate the simple percentage method for MDR when calculating the time for an unplanned diversion as has been described.
But for pre-flight planning, I expect the student to use a computer of some form, not MDR.
And as for the organisation which teaches people to use still air planning at medium level if the wind is 'less than about 10 kts'.... That's just laziness; fair enough if the wind is 'light and variable', but if you start out with such a 10-12% error in groundspeed, then on a typical 50 mile leg you'll be outside the PPL Skill Test limits before even taking off.
But for pre-flight planning, I expect the student to use a computer of some form, not MDR.
And as for the organisation which teaches people to use still air planning at medium level if the wind is 'less than about 10 kts'.... That's just laziness; fair enough if the wind is 'light and variable', but if you start out with such a 10-12% error in groundspeed, then on a typical 50 mile leg you'll be outside the PPL Skill Test limits before even taking off.
The whizzwheel won me a heart for the night many many years back when I was a callow PPL youth. It was in my top pocket and while chatting up a young lady I convinced her I was an aerodynamicist because I showed her my "circular slide rule." I mumbled something about lift formulae of her boobs quoting Lift = CL half row something V squared alpha and showed her how to work the whiz wheel and Bob's yer Uncle...
BEagle:
who's teaching people to use still air planning at medium level if the wind is 'less than about 10 kts'?
The advantage of using MDR for pre-flight planning is that the techniques are then fresh if you need to plan a diversion. How many non-mil pilots have you flown with on refreshers or LST/LPCs who pre-plan with a wizzwheel and can still plan and fly a diversion properly?
AWL:
I wish you success selling your gadgets but they really aren't necessary. Anyone with a circular DI (or any other compass rose) can do all the drift/gs planning just by calculating MD (WSx60/TAS) and then visually using the DI to estimate the drift and T/HWC on any heading. It takes less than 30 seconds.
Having said that, one gadget which people who struggle with 2+2 find very useful for estimating durations is a scale with distance/time for different GS - Transair sell one but it's simple to make one.
HFD
who's teaching people to use still air planning at medium level if the wind is 'less than about 10 kts'?
The advantage of using MDR for pre-flight planning is that the techniques are then fresh if you need to plan a diversion. How many non-mil pilots have you flown with on refreshers or LST/LPCs who pre-plan with a wizzwheel and can still plan and fly a diversion properly?
AWL:
I wish you success selling your gadgets but they really aren't necessary. Anyone with a circular DI (or any other compass rose) can do all the drift/gs planning just by calculating MD (WSx60/TAS) and then visually using the DI to estimate the drift and T/HWC on any heading. It takes less than 30 seconds.
Having said that, one gadget which people who struggle with 2+2 find very useful for estimating durations is a scale with distance/time for different GS - Transair sell one but it's simple to make one.
HFD
If it worked for your dad...
I teach my cadets to try and do everything with circular computers. It freaks them out how easily, and accurately most things can be calculated on the Whizz.
Recently I held an informal briefing on the lost art of 'Whizzing'. Taught how to calculate the cost of each can of beer (6pack vs carton), exchange rates and how fast your car goes (percentage Mach).
Personally, I have recently discovered how to calculate head/cross wind components using the SIN/COS feature on the wind calc side. All you need to know is the difference between track and wind origin, and wind strength. Set COS 0 (the top) to wind strength on outside scale. Then decide if you want to calc crosswind or headwind.
Want to know wind on your SIDE? Use SIN. - X wind
Want to know wind on you COCK? Use COS. - Head/Tail wind.
Being really crude helps me remember, so sorry about writing cock.
If you wanted to get really technical, you could calculate 'ETAS', or effective tas reduced by wind drift... Don't worry, blame the slower performance on your crate.
Back to the whole point, people far smarter than use designed an incredibly intimidating device, which is really very easy to use. The Jeppesen CR series are the only way to go, the sliders do not have enough functions and get out-grown. I'm sure every one of use would love an original Brietling Navitimer with authentic slide ruler in the bezel...
And chicks won't steal the batteries from it to put into remotes.
Recently I held an informal briefing on the lost art of 'Whizzing'. Taught how to calculate the cost of each can of beer (6pack vs carton), exchange rates and how fast your car goes (percentage Mach).
Personally, I have recently discovered how to calculate head/cross wind components using the SIN/COS feature on the wind calc side. All you need to know is the difference between track and wind origin, and wind strength. Set COS 0 (the top) to wind strength on outside scale. Then decide if you want to calc crosswind or headwind.
Want to know wind on your SIDE? Use SIN. - X wind
Want to know wind on you COCK? Use COS. - Head/Tail wind.
Being really crude helps me remember, so sorry about writing cock.
If you wanted to get really technical, you could calculate 'ETAS', or effective tas reduced by wind drift... Don't worry, blame the slower performance on your crate.
Back to the whole point, people far smarter than use designed an incredibly intimidating device, which is really very easy to use. The Jeppesen CR series are the only way to go, the sliders do not have enough functions and get out-grown. I'm sure every one of use would love an original Brietling Navitimer with authentic slide ruler in the bezel...
And chicks won't steal the batteries from it to put into remotes.