GRP, your post makes a lot of sense, thanks. I think I might try your suggested technique the next time I'm doing a cross-country of any distance to see whether I like it in practice!

FFF
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Having thought about this since I posted that, I suspect there is a confusion as to what we mean by our 'primary' means of navigation. For my money saying that GPS is my primary means of navigation means that once I am in the air I use the GPS as the means of determining whether I am on track, rather than using VOR, ADF or dead reckoning. None of this for my money means you should not draw lines on a chart and follow your progress along those lines when you are in the air. I certainly do not mean that I use the GPS map to avoid the need to use a chart! In my case I have an autopilot coupled to the GPS and can have the track error from the GPS displayed on my normal CDI instrument. So the map on the GPS normally displays where I came from, where I am going to and a pink line in between with hopefully a little aeroplane on it sitting on the line pointing somewher in the direction of the line. It also displays the odd airfield en-route if they are large enough for my settings to allow them to show up. Occasionaly you see a wobbly line on it which is a coastline. Sometimes I have the airspace displayed so I can see when I am reaching the FIR over the channel. I can change the detail displayed by repeated pressing of the CLR key. Works for me, and as far as I am aware, minus the autopilot coupling, can all be done with the Pilot III.

Being a cheap-skate, I bought a second-hand Magellan. If I'm flying from A to B, all the GPS will tell me is that I have to turn right or left a bit, I've still got X miles to got, I'm doing Y ground speed & I'll get there in Z minutes.

It won't tell me where I am, which is great because it means I have to look outside and at the map. All it will do it to make sure that I am on track, following the line on the map.

Where you are is probably X miles back along the track you set up and offset by how far it says you are off track! Bit like getting a fix from a VOR and DME I suppose!

BRL,

there are a few pics of my Casio MM setup here

Cheers
EA

Thanks Al... :)

I would like to make one more comment regarding the safest, easiest and best way to fly from A to B.

For me the easiest and most comfortable is to apply take off power and rotate to the correct deck angle as I enter cloud just after lift off. As long as I stay in cloud and follow the clearance issued and read back I am as safe as Aviation will allow. A plus is to have either the Airbus or Boeing PFD and ECAM to make life even easier.

With the foregoing I can toss my sectional map in the back pull out my latest picture book and look at the pictures, until ATC askes me some trivia like squak ident.

So there you all have the easiest way to navigate. ( By the way both Airbus and Boeing use GPS as one of the nav aids being compared against the older methods. )

Cat Driver:

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:D The hardest thing about flying is knowing when to say no.:D

Chaps - can anyone recommend a good WWW site that explains more of how GPS systems work for aviation?

I'm wanting to buy one (love gadgets), but I'm not sure whether to go for an EnglishAl kind of setup (prob an iPaq plus some sort of receiver) or to go for the all in one incl. database kind of thing (Skymap, Pilot III etc.)

For what it's worth on the "why not buy a cheaper civvie GPS unit" question, I have a Garmin GPS II (use it on the m/bike and have all local GATSOs prog'd in as waypoints) this unit actually shuts off at 103mph. Thi is going to make it useless even in a C152! (and on a Fireblade ;) )

Cheers
Hersh

The one thing I'd say about the setup I use is that its very easy to change software, update databases cheaply, customize etc. If you go for a purpose built portable aviation GPS unit then you're stuck with it and its software. Also you're somewhat limited in that database updates are only available from the GPS manafacturer. There is constantly more aviation software becoming available for the PocketPC all the time. For example in the US you can interface the PocketPC with a GPS receiver and also with a receiver which gets weather radar images transmitted from the ground in almost real time and overlays them onto the moving map.

Virtually all moden GPS receivers are the same when it comes to accuracy in the form of position, so a cheap £100 unit will generally give as accurate results as a £1000 unit. I've had a $90 eTrek operate at over 200kts with no problems. If you're planning IFR flight then of course you have to go for a panel mounted IFR certified jobby, and keep the database up to date.

With the iPaq you can get a Compact Flash GPS card which slots into the unit which looks pretty cool. For around £800 inc the iPaq you get something which in my opinion is better than any portable aviation GPS unit.

If anyone is interested, you can find out how GPS works by taking a look at http://www.howstuffworks.com/gps1.htm

Cheers
EA