Flight computer and navigation
The Original Whirly
Join Date: Feb 1999
Location: Belper, Derbyshire, UK
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What I use depends on what sort of flying I'm doing. For a local bimble, I'll draw a line on the chart, maybe, and measure it, and that's about it. For something a bit longer, in light winds, I'll draw the line and do an approximate estimate of drift for the wind. If crossing France, with few ground features, I'll still draw my line, but I'll use VORs and GPS. But for a long trip in the UK, I'll use my whizzwheel. Why not? Once you're really in practise, it's as quick or quicker to use this than any of the approximations. It only seems complicated at the beginning. When you're used to it, it's fast, accurate, easy to carry around, doesn't need batteries, and doesn't go wrong. Those who disagree probably never learned to be that comfortable with it in the first place.
Fixed+Rotary (aircraft, not washing lines)
Join Date: Jan 2005
Location: Peak District, Yorkshire, UK
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I use www.goflying.org to get a plan for my route - it is a free service provided by another PPrNer.
BUT - as all these services have disclaimers about accuracy and reliability I also double check the results with my whizzwheel - it takes literally seconds and as Whirlybird points out it is always there, no batteries, accurate etc.
I too found the whizzwheel quite difficult to get to grips with. Different lines representing different parts of a triangle etc. until an instructor showed me a short cut which I only promised to use once I understood the principles and could use the 'standard' method.
e.g. following the example in Trevor T. Navigation, page 74.
TAS 97, W/V 320/25, TR 295
Take your CRP-1 or other...
1. Set the blue circle over the TAS (97)
2. Turn the inner circle so that 320 (Wind dir) is aligned with INDEX at the top
3. Mark a dot 25 (Wind vel) units BELOW the blue circle. I.e. a dot on the vertical centre line at 72.
4. Turn the inner circle so that 295 (TR) is aligned with INDEX at the top.
Your dot should now be on the 75 speed line, and 8 degrees to the LEFT of the centre line.
5. Move the 295 marker at the top to the LEFT so it is aligned with 8 on the drift scale.
Your dot should now be on the 73 speed line, and about 5.5 degrees LEFT.
6. Move the 295 marker on the inner circle so it is aligned with 5.5 on the LEFT hand drift scale
Your dot should now be on the 74 speed line, and about 6 degrees LEFT.
7. Move the 295 marker on the inner circle so it is aligned with 6 on the LEFT hand drift scale
Your dot should now be on the 74 speed line, and about 6 degrees LEFT.
You have reached your destination, the dot and the drift offset are the same.
8. Read off the heading below the INDEX mark: 301
9. Read off the speed on the speed line: 74
OK. So Trevor T. gets 301 and 73 but I'll allow the 1 knot due to the fatness of the dot on the CRP-1.
Basically - you are making smaller and smaller changes until the the two offset numbers meet. Remember that if the dot moves to the right side initially then work with the RIGHT drift scale. No lines, no triangles, nice and simple.
Using this method a HDG and GS calculation can be made in seconds which is mainly what you will need. Since the exam I've never had to worry about calculating W/V etc. in the air.
Saying all that - I'm now learning to use VORs and GPS much more and I make more use of them in future I guess.
BUT - as all these services have disclaimers about accuracy and reliability I also double check the results with my whizzwheel - it takes literally seconds and as Whirlybird points out it is always there, no batteries, accurate etc.
I too found the whizzwheel quite difficult to get to grips with. Different lines representing different parts of a triangle etc. until an instructor showed me a short cut which I only promised to use once I understood the principles and could use the 'standard' method.
e.g. following the example in Trevor T. Navigation, page 74.
TAS 97, W/V 320/25, TR 295
Take your CRP-1 or other...
1. Set the blue circle over the TAS (97)
2. Turn the inner circle so that 320 (Wind dir) is aligned with INDEX at the top
3. Mark a dot 25 (Wind vel) units BELOW the blue circle. I.e. a dot on the vertical centre line at 72.
4. Turn the inner circle so that 295 (TR) is aligned with INDEX at the top.
Your dot should now be on the 75 speed line, and 8 degrees to the LEFT of the centre line.
5. Move the 295 marker at the top to the LEFT so it is aligned with 8 on the drift scale.
Your dot should now be on the 73 speed line, and about 5.5 degrees LEFT.
6. Move the 295 marker on the inner circle so it is aligned with 5.5 on the LEFT hand drift scale
Your dot should now be on the 74 speed line, and about 6 degrees LEFT.
7. Move the 295 marker on the inner circle so it is aligned with 6 on the LEFT hand drift scale
Your dot should now be on the 74 speed line, and about 6 degrees LEFT.
You have reached your destination, the dot and the drift offset are the same.
8. Read off the heading below the INDEX mark: 301
9. Read off the speed on the speed line: 74
OK. So Trevor T. gets 301 and 73 but I'll allow the 1 knot due to the fatness of the dot on the CRP-1.
Basically - you are making smaller and smaller changes until the the two offset numbers meet. Remember that if the dot moves to the right side initially then work with the RIGHT drift scale. No lines, no triangles, nice and simple.
Using this method a HDG and GS calculation can be made in seconds which is mainly what you will need. Since the exam I've never had to worry about calculating W/V etc. in the air.
Saying all that - I'm now learning to use VORs and GPS much more and I make more use of them in future I guess.
After flying my first nav exercise yesterday, I'd say that using a wizz-wheel is much easier than flying the headings that you've calculated!
Hopefully it will get better (and the viz was really poor, but that's making excuses!)
A
Hopefully it will get better (and the viz was really poor, but that's making excuses!)
A
Join Date: Sep 2002
Location: Savannah GA & Portsmouth UK
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Coodem
I use a Garmin 196. The way I do it is:-
1. Plan the route on the chart to avoid things that are best avoided.
2. Stick the route into ProPlan - it'll remember it so you can use it again in the future.
3. Get the wind off the Met Ofifce site and NOTAM from AIS
4. Stick the wind into ProPlan and print a detailed PLOG
5 Upload the route to the Garmin (if it's not in there already)
6. Print the en-route frequency list from ProPlan
7. Go Fly!
I subscribe to the ProPlan updates.
I use a Garmin 196. The way I do it is:-
1. Plan the route on the chart to avoid things that are best avoided.
2. Stick the route into ProPlan - it'll remember it so you can use it again in the future.
3. Get the wind off the Met Ofifce site and NOTAM from AIS
4. Stick the wind into ProPlan and print a detailed PLOG
5 Upload the route to the Garmin (if it's not in there already)
6. Print the en-route frequency list from ProPlan
7. Go Fly!
I subscribe to the ProPlan updates.
The Original Whirly
Join Date: Feb 1999
Location: Belper, Derbyshire, UK
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Hopefully it will get better (and the viz was really poor, but that's making excuses!)
Join Date: Nov 2001
Location: UK
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I confess I have no idea where my whizz wheel is. I go with IO540, though I always draw a line on my chart, take my 10nm thumb with me and a stop watch. I also note headings on my PLOG though not usually times since unless I loose all the electrics and the spare handheld GPS I've usually got that readily to hand.
Crude knowledge of the wind, drift angle and speed together with a 10 mile thumb will give you a quick approximation to times on the fly if push comes to shove anyway.
Crude knowledge of the wind, drift angle and speed together with a 10 mile thumb will give you a quick approximation to times on the fly if push comes to shove anyway.
Join Date: Jun 2003
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For VFR, I draw a line on the chart too - may as well since already using it for controlled airspace and terrain planning.
Unless one is able to print out sections of the actual VFR chart, showing the route, which is possible (very expensively) with Jeppesen Flitestar ...
"And then, IMHO, is the time to use VOR and GPS and anything else you've got as a back-up."
Better to use the GPS as primary, with anything else you have as a backup. GPS is the best device by far. Otherwise, it's like travelling somewhere, on a bike, with a motorbike on a trailer in case the bike breaks. Aviation tradition says that the bike is the "proper airmanship" way to do it. Outside aviation, nobody would bother to make their life deliberately harder. Of course, these comments make instructors really mad.
Unless one is able to print out sections of the actual VFR chart, showing the route, which is possible (very expensively) with Jeppesen Flitestar ...
"And then, IMHO, is the time to use VOR and GPS and anything else you've got as a back-up."
Better to use the GPS as primary, with anything else you have as a backup. GPS is the best device by far. Otherwise, it's like travelling somewhere, on a bike, with a motorbike on a trailer in case the bike breaks. Aviation tradition says that the bike is the "proper airmanship" way to do it. Outside aviation, nobody would bother to make their life deliberately harder. Of course, these comments make instructors really mad.
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I'm a bit behind the time on this and referring to IO540's earlier post, I do enjoy reading his various diatribes 
The usefulness and functionality of a device is not inversely proportional to its longevity, often the opposite! Nobody in their right mind would use a whizz-wheel in the cockpit, it is only a planning tool. Rules of thumb technique are necessary/essential knowlegde and I've never met an instructor who disagrees with this. Rules of thumb augment any navigation method be it VFR, IFR, GPS, RNAV, DR, etc.
My observation is that learning to use a whizz-wheel is really part of the process of ingraining the notion that you need to be vigilent with regards to the various metrics and conversions required in the flight planning process. I would argue that the use of one universally capable metrics tool in the training process helps structure and standardise the corresponding processes, rather than having to use this piece of software for this and that calculator for that, etc.
The usefulness and functionality of a device is not inversely proportional to its longevity, often the opposite! Nobody in their right mind would use a whizz-wheel in the cockpit, it is only a planning tool. Rules of thumb technique are necessary/essential knowlegde and I've never met an instructor who disagrees with this. Rules of thumb augment any navigation method be it VFR, IFR, GPS, RNAV, DR, etc.
My observation is that learning to use a whizz-wheel is really part of the process of ingraining the notion that you need to be vigilent with regards to the various metrics and conversions required in the flight planning process. I would argue that the use of one universally capable metrics tool in the training process helps structure and standardise the corresponding processes, rather than having to use this piece of software for this and that calculator for that, etc.
Join Date: Jan 2006
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Given that my last post (see "where the .... am I) was a tale about how I got confused about my position I almost hesitate to comment here, but here goes. I think that the whizz-wheel is a good tool for pre-flight planning if you are still pursuing the 'steam-driven' approach and also a good device for helping to teach the principles of navigation. I still do my pre-flight planning using one and, as long as the wind forecasts are reasonably accurate, is an enjoyable and satisfying process.
Arguably, one of the reasons I found my self in the ordure was that I hadn't done any planning and simply relied on my knowledge of an area I know well.
However, I seriously doubt that I could use a CRP-1 in the air with any degree of confidence - too much like riding a uni-cycle, blindfolded, around the rim of the pit of doom whilst reciting one's times tables.
Arguably, one of the reasons I found my self in the ordure was that I hadn't done any planning and simply relied on my knowledge of an area I know well.
However, I seriously doubt that I could use a CRP-1 in the air with any degree of confidence - too much like riding a uni-cycle, blindfolded, around the rim of the pit of doom whilst reciting one's times tables.
Why do it if it's not fun?
Join Date: Jul 2001
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Whirlybird said:
All very true. It's not impossible to fly visually in very poor viz (even down to 3km or less), but the whiz wheel and traditional ded-reckoning techniques are definitely not the way to go. In this kind of viz, use line features - the bigger the better. Follow the line features until you reach good position fixes on those line features, e.g. follow a motorway until it reaches the town, then follow the edge of the town to the destination airport.
If you're starting somewhere other than a line feature, then find a line feature to follow, and fly to it - but fly to one side of your first position fix. E.g. fly to the south of your position fix, then turn north to follow your line feature - that way you know that your first position fix will be in the direction you are going.
Definitely not the kind of navigation for student pilots or low-hours pilots to be attempting un-aided, but certainly not impossible, and (like a lot of difficult things) very rewarding when it goes right! And if the weather is that bad, you'll probably be using up some of your capacity simply keeping the aircraft the right way up and maintaining VMC, too.....
Alternatively, follow Whirly's suggestion and use any nav-aids available!
FFF
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Once the vis is down to 7 or 8km (it doesn't have to be really bad) it's much harder, and you really have to be on the ball to notice if your heading isn't working. That may be because the wind has changed or whatever, not because you're not flying accurately. And then, IMHO, is the time to use VOR and GPS and anything else you've got as a back-up
If you're starting somewhere other than a line feature, then find a line feature to follow, and fly to it - but fly to one side of your first position fix. E.g. fly to the south of your position fix, then turn north to follow your line feature - that way you know that your first position fix will be in the direction you are going.
Definitely not the kind of navigation for student pilots or low-hours pilots to be attempting un-aided, but certainly not impossible, and (like a lot of difficult things) very rewarding when it goes right! And if the weather is that bad, you'll probably be using up some of your capacity simply keeping the aircraft the right way up and maintaining VMC, too.....
Alternatively, follow Whirly's suggestion and use any nav-aids available!
FFF
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Join Date: Mar 2004
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The Whizwheel is a good tool you would be surprised how many commercial pilots use them. Until recently many North Sea helicopter flights were planned using the whizwheel and they are still used for fuel planning long range SAR sorties.
Join Date: Sep 2003
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biggest pile of pap going and more prone to errors than an ADF on a stormy night........
Managed to fly 1500hrs without one and the to do the JAR IR had to learn to use a VFR flight tool again. Still hate it and if I passed the last exams really will throw it in the bin or put iton eBay this time.
ASA Electronic calculator for me and guess what you can actually use that one in the air assuming that I had a total electric failure and the backup batteries on the GNS430 and the 296 both failed........ Of ocurse of the batteries went flat on the ASA as well, I really would be having a bad day.....
Managed to fly 1500hrs without one and the to do the JAR IR had to learn to use a VFR flight tool again. Still hate it and if I passed the last exams really will throw it in the bin or put iton eBay this time.
ASA Electronic calculator for me and guess what you can actually use that one in the air assuming that I had a total electric failure and the backup batteries on the GNS430 and the 296 both failed........ Of ocurse of the batteries went flat on the ASA as well, I really would be having a bad day.....
