A GPS Question

[Thief13x]

Hi, i'm almost ready to take my practical test, and i'm planning on buying myself a present afterwards...a GPS:D

I was pricing them, and obviously they're all pretty expensive, which doesn't bother me, i know it will be worth it...or will it?

On to my question. I was looking at a GPS that displays cities, roads, airspace and railroads and i just had one question. If they display all that, how do you update them as things change? obviously they update sectional charts every few months, and there must be a reason for that, the fact is that things change. What good is a GPS that displays false information? The airspace is the biggest variable in my mind, what if somthing changes? maybe a Class B airspace is expanded and you forget about it while looking at this outdated GPS that shows somthing different. How does all this work...anyone?

Dave

[Final 3 Greens]

Hi Dave

Basically you buy updates that are downloaded into the GPS, thus bringing it back up to date.

[pbloore]

The only GPS I've used a lot is the Garmin GPS III pilot which has a fixed land basemap (ie: cannot be updated) and a Jeppesen aviation database. The latter can be updated by one off updates valid for one month or by taking out a 12 month subscription giving you monthly updates.

For myself I purchase updates about once every six months. Because I don't use the GPS for primary navigation this is quite sufficient for my needs.

The GPS III has the great advantage for me that it will sit in a pocket or my flight bag taking up very little space and if I get stuck I can switch it on and it's up and running in a couple of minutes from a cold start.

All of the portable Garmin aviation units use the same databases and I think the same applies for most of the others .
The Garmin 196 is very good with a big clear display but still protable, the colour 296 is very sexy with topgraphical info also (but at a price). In the past I've use a SkyMap which was excellant and I know others swear by the Magellan range.

Best policy is to go to a dealer where they're all on demo and give them a try. A good tip is to see if you can drive a unit without using the instructions.

In short a portable unit is invaluable as a backup aid.

[Thief13x]

Hmm, thanks guys. Are updates relativly cheap?

[bfato]

USD35 for one, or USD295 for 13 consecutive.

All info is on the Garmin site (http://shop.garmin.com/aviation/databases/)

[bar shaker]

Pbloore

Having a GPS in a bag, switched off but ready to be turned on when you get lost is, probably the biggest thing that scares NATS/CAA about GPS use.

If you have one, leave it in the car or turn it on before take off so its ready for you to look at, if you need a second opinion on postition.

Thief13x

Airspace upgrades are from Jeppersens database, via Garmin's website and cost about £20 a go or roughly £200 for 13. The land (road) map is in low res but you can load on hi res maps from Mapsource. These go on your data card and you need approx 64k for the whole of the UK. The detail is very high, including petrol stations and all sorts of other info. You can turn much of this off and can declutter the screen too. The manual says that it doesn't like being a road nivigator with Mapsource enabled, but it works pretty well, only getting lost if the low res road is some way away from thetrue position.

196 are about £550 and are very good. The 296 has coloured terrain maps, but I always fly VFR so don't need this function.

[Fly Stimulator]

Thief,

Some translations of terms in Bar Shaker's post which may be unfamiliar to you:

£ - the symbol for 'pounds', the currency we use in the absence of the dollar on this side of the Atlantic.

UK - England, plus some outlying areas you don't need to bother with. No longer includes the USA, though if you can find a Garmin UK database from the early eighteenth century it may include your local area.

Petrol - similar to gas, but much more expensive.

;)

[bar shaker]

LOL at Fly Stim :D

Sorry about that Thief, I didn't check your location before replying. In fact I even did the mental arithmatic to convert $ (quoted by Garmin) to our Pounds.

Everything FS says is true.

[Pronto]

Just a couple of points to add - one piece of advice and a general observation for you to consider.

I have a GPS which I use as a backup only. This is a non aviation one, which cost just under £100 when bought new about 3 years ago. (That's about $180 at current rates of exchange). No moving map at all. Bar Shakers advice regarding turning it on before you fly is good. I once did a 45 minute flight with the unit sat atop the glareshield and not managing to acquire the satellites at all. I'd forgotten to turn it on before I took off. (That was in a tired old Warrior cruising at 95kts). To be fair, an instructor who has an identical GPS tells me that he's been able to turn his on and acquire the satellites in flight, no problem and that in a faster aircraft. The lesson may well be to try out your set and see whether it'll reliably acquire in flight. If not, turn it on before you go.

One of the other aircraft I fly has a full moving map display. The refresh rate with this is such that I find it more of a distraction than a help. Also, the way this is set up doesn't much help either, as the mapping turns to give the direction of travel at the top. Accordingly, if you're going south, then south is to the top of the display which I find disconcerting. As it's a hired aircraft used by many, I can't really play with the settings without inconveniencing others.

It may be worthwhile borrowing a GPS from a friend and see how you get on with it rather than pay a large sum of money and find you'd have been better off with a much cheaper, non aviation GPS, which will tell you where you are, what direction you're going in and how fast.


P

[pbloore]

Hi there,

I carry a backup kit in my flying bag in case things go wrong which includes the GPS II Pilot I mentioned, an ICOM handheld (with VOR), torch etc. As a general rule I don't use any of these while flying but rely on the (legally required) map. Having said all that I now have a panel mount GPS which provides a handy backup as well as a full nav panel.

The GPS III will start up from cold out of my flying bag and will usually locate itself within a minute and has never taken more than two in my experience so is a good backup. I sincerely hope than I will be able to realise I'm loosing my positional awareness well enough in advance to switch it on before I get really 'unsure of position'.

I have resorted to using the ICOM and for that matter the GPS when we had a generator failure and I flew the plane for maintenance with the master off (once started of course) so they have come in useful.

I still find the GPS III a very easy unit to use - I haven't got my head around the panel mount one yet apart from simple gotos and routes. For some reason it doesn't seem so intuitive.

[bar shaker]

To me not turning it on seems like going out on a rowing boat and taking arm bands as your bouyancy aids... but not blowing them up first.

Its in the bag, its not turned on, you are becoming less sure of position. You are straight and level at 2300, 130kts. After another look at the map and the countryside you decide to turn on the GPS and because there's a few CBs around it takes 2 mins to locate itself.

From the start of that paragraph, to the end, has put you over half way across the Stansted zone.

Finally, its a machine. Unless its on and working properly, in front of your eyes, it is Sod's 43 law that it will fail at the time when you will be most strongly relying on it to work. If its working and stops working, you know that your dead reckoning is now your only nav option.

PB, I can understand leaving it off if you have a nice panel mount. And the Pilot III is a superb bit of kit for almost no money, if you can still find one.

[SR20flyDoc]

If you really want a good present, I have one for free for you ( meaning € 0,00 , don't know about any local currencies on this side of the pond := )

You can download it at www.garmin.com and it's a Garmin 430 / 530 simulator. If you practice, you will never want to fly anything without the real stuff again. Plus you can plan all your trips on the ground with it. :cool:

If you do want to get portable, I recommend the Skyforce ( now Bendix/Honeywell ) Skymap IIIc for color and terrain Good point; the basemap is the whole world, unlike the portable Garmins which has no update for the basemap, only works in either the U.S. or this side of the pond . Big and bright. If you are on a budget , get the Lowrance 100. Jepp database cost the same as for Garmin, but DOES have obstacles in the database.