Using the 'printed Skydemon PLOG'...
 

Tagged this on to the back of a 'Skydemon thread' but didn't get much joy.. More for my own information purposes really.

I flew over to Cambridge last week Tuesday and was carrying my "first passenger". I planned the flight manually using the CRP-5, Wind Corrected and noted it all down on a Pooleys VFR PLOG.

As a precaution I also took out a sub to SkyDemon to run on my Android Phone - only to find that you are able to "plan and print the PLOG" also and use this for your flying. The only time I needed to use SkyDemon was to confirm I was actually overhead Chedburg turning en route to Cambridge.

Having it on my lap gave me the piece of mind that should I not know where I am I can always look at the Sky Demon.

I had my half mil chart with track over the Ground with half way points and drift lines marked.. One thing I noticed when comparing both SD PLOG and my Manual PLOG was that in my Manual planning - I didn't "interpolate" the Wind at 2000ft for each leg according to Lat/Long - and used the 2000ft wind at my home airfield for the whole journey.

I found that the headings from SkyDemon/Wind was different to my "Manual Calculations".. only by +/- 1 to +/- 3 degrees. I still got to Cambridge flying my manual PLOG and then experienced "flying only GPS" for the journey back to base. Again I noticed how my much mental capacity was released to fly the plane - when doing things by GPS only.

However, I would always like to know where I am visually also - by reference to towns/rivers/railways etc.

How "accurate" is the PLOG on SD and if using such navigational tools, should one also do everything manually or just print off the PLOG from SkyDemon?

Also when doing a manual plan - vs - skydemon PLOG - I normally only use the 2000ft wind at my base destination... but SD 'interpolates' the wind across the flying zone.

Should this be done manually also? If so how?

I am just thinking time wise - I could have saved myself the planning time but of course I am trying to do everything the way I was taught manually. Though the arguments by some instructors are also - we teach you to fly manually but wouldn't blame you if you were to fly via using a GPS later due to controlled airspace restrictions.

Ta!

Scoobster

I use the SD plog, I give it the once over to make sure it doesn't have any spectacular errors and use it. It's about as accurate as using the whizz wheel in my experience. It just saves time, plus if you ever saw my handwriting you would know why a printed plog is so much better.

I always mark a map up; as I've said before it helps to get the route into my head so that when I look at the pink string it's just confirming that I'm where I think I am. Plus your GPS can always go u/s and if you're flying blindly on it you will be in a world of, if not trouble, embarrassment as you call your local ATC unit for a steer. Having said that you should never be embarrassed about asking for a steer but the reason you ask for one might be embarrassing to you personally.

I'm am trying to do as I was taught and that wasn't with GPS - whilst I am learning anyway or for hours building etc. It will be back up tool.

What I am trying to establish is how accurate the PLOG is etc and if it is OK to print it off and use that from a planning perspective?

I suspect it may be slightly more accurate unless you interpolate the forecast winds, at each waypoint in your manual planning.

Sort of like take the good parts of SD (which seems to be interpolation of winds, tracks etc) and incorporate it into Manual Flying and Manual VFR PLOGS with Pen - PLOG.

Do you mean with track over the ground? I have heard of 2 different terms on here.. "Track Up" and "North Up" - What is the difference from a planning perspective?

I mean I was taught the half mil chart is "North Up" and we just mark the "track over the ground" and use that as a basis to see if we veer off course and for drift calculations etc.

Scoobster

Can you maintain a heading to within 3 degrees?
What you did was sensible, prepare both plogs and compare them, any large discrepancies would indicate an error somewhere. As for interpolating winds, remember they are forecasts so by definition are a guess by someone, try not to over analyze the big picture.

Happy flying

Very true! I will shut up now :}

Scoobster

Never be afraid to ask advice, but always consider some advice is good, some may not be so useful.
Track up/north up probably refers to how you hold your chart. Some people always leave north at the top, some orientate the chart so that the track on the chart is pointed in the direction you are going. Either is fine, use which works for you.

Yes you mark a map up with desired track over the ground...I hope that you were taught this during your nav phase?

There's no difference in planning perspective between north up and track up. It's whatever you prefer. I can't do track up, some people can't do north up. Depends how the old grey matter works I think.

I fully agree with Bingo, don't over egg it. As you get more hours under your belt the 'I need to alter course a degree' will go out of the window and 'There's that power station that's my next waypoint 30 miles in front, am I heading towards it with a rough guestimate for drift added in, yes, then all is well with the world' will start to seep in.

Edit: One of our milk runs is to take our aircraft up to Sherburn for servicing, about 45 miles as the crow flies. On a reasonable vis day you can see Sherburn when you climb out of the circuit at my home base. You don't actually see Sherburn, you see Eggborough power staion which is where Sherburn is as near as damn it. How do I know it's Eggborough? Because it's sits in the middle of Drax and Ferrybridge power stations. Job done, no map required, no GPS required, just a crossing of Donny zone to negotiate and sit back and relax.

Yes. This is what I do as standard.. Was just confused with the "track up"..thought it was a replacement for the "map facing north".

I always mark a chart with the track over the ground but hold the map "facing North" - with North side upwards.

Thanks for the input.

Scoobster

Just to clarify, the lines on the map are exactly the same, there is no difference in how you mark the chart, well actually there is, if you turn the chart until the track line you drew is pointing in the direction you are flying, you might want to write any notes or numbers so that you can read them with the chart rotated on your knee to 'track up'.

It is not a different planning technique, it just refers to how you hold your chart in the aeroplane.

Ah, good man! We ought to start a North Up club.

I always use a PLOG for all but a local flight in very well known territory (and even then, probably have the PLOG sheet on my kneeboard to write down useful numbers).

I've used the SD PLOG a few times. It works, but I find it a bit sub-optimal.


Here's the trick I worked out a lot of years ago. I have a computer, it has a word processor on it. Design your own, to suit the way you like to write stuff down. Make sure it's compatible with SD, or any other software package you use - but if you designed it, it'll be right.

Printing out half a dozen to keep in your flight bag is easy, copying the critical numbers from your software is also easy. Drawing a line on a chart's not a bad idea either.


Yes the SD plog works, yes it's not a bad idea having stuff on paper in addition to anything electronic. No, it won't work as well as a PLOG you designed that suits your style of flying.

My PLOG is at probably its 10th revision in 15 years since I realised I could do it that way, and each one gets that tiny bit closer to personal perfection.


As for winds, they're never what the Met Office forecast, and your interpolation is always a best guess. Also, few aeroplanes fly quite at the speed in the POH (came across one the other day that actually went faster!). So, don't get too hung up on how exactly you use the numbers off the forecast, as they'll be a bit out anyhow.

GPS is great - use it. But integrate it with old fashioned methods: don't use it to replace them.

G

There's one already:O

National Luddites Association... how may I help you?" - Cartoon Poster Print by Mick Stevens at the Condé Nast Collection

Magenta line and North up
 

There's a case for a map to be used North up - makes it easier to read the writing printed on it.
I once had to hand-fly an aircraft, form the right seat, over ocean for 3 hours with the GPS set to North up. The problem was, the track was due South. Nearly did my head in, making opposite corrections to stay on track. OK, OK I was setting a heading to fly then referencing the GPS, but ever since then, I've been 'track up' with the GPS. After all, it's default mode in the car...
TOO

I find it discouraging how many still bleat on about the horrors of using the GPS and are proud of the fact that they deliberately reject using the benefits of modern technology to increase flight safety and efficiency.

The PLOG was invented to overcome the navigational problem that existed prior to the advent of GPS, namely there was no way to instantaneously and continuously update your present position. To overcome this various strategies where methods, most derived from nautical navigation techniques, are used to predict where you would be in the future, and to correct track errors when you could again fix you your position.

The underlying raison d'etre of traditional navigation doesn't exist with GPS because you always know exactly where you are and will always have up to date numbers for all the values you used to have to calculate or infer, like ETE/ETA. Ground Speed, Track, Track deviation etc etc

So does that mean should there is no value in traditional nav ? Absolutely not but it should be now used in a more holistic way. The problem with GPS is that it will do exactly what you tell it to do. If you tell it the wrong thing than it will take you where you did not want it to go. So how to protect yourself ?

I teach my students to use GPS accuracy backed up by a mental TLAR ( That Looks About Right), check. So if you flew from A to B and the track was 225 and now you are flying back to A and the GPS say the track is 017 you should immediately say "Hey that doesn't look right !"

So double check the numbers from the magic box before you take off, Keep your finger moving along the paper map, no lines needed :ok: as you fly, use the GS and ETE values to update you fuel at destination calculation, TLAR any changes., and enjoy a better, safer flying experience.:)

Finally, make sure you know and understand the GPS database and "nearest" feature. When the chips are down getting a pointer to the nearest airport with track, distance and time instantaneously displayed, all with a few button pushes, could literally be a lifesaver.

I totally agree that GPS flying with TLAR is a good thing, but you need to remember that GPS can fail and you need a backup of some sort. If you only have other GPS as backup then those would be useless if the satellites themselves stop working.

Anyway, if you always know where you are with the TLAR picture, then creating a new flight plan on the spot when GPS fails is as simple as a diversion practise during flight training. We're here, let's go there.

The chance of all GPS to fail is very low, and multiple redundant GPS devices backed up with a good old paper map is very sufficient in my opinion.