GPS -v- MAP

[J170 Owner]

not that you should ever not use maps, but to play the devils advocate (bare in mind my very limited experience) surely there is a huge difference between using a car gps and an aviation gps?

Hi. I use a car GPS as a backup for my navigation while flying. I enjoy using a map and compass and doing the times/speed/distance calculations as all good pilots should do. I consider it to be 'what flying is about'. However, my Garman Nuvi GPS in off road mode is just great. I enter my destination and way points and it draws a pink line joining them, as I fly a blue line shows my track and I can easily see if I am keeping to my intended track. After a flight I can load the resulting GPX file into Google Earth and display it as well as play it back.

 

 

[MarcK]

With vehicle GPS the error Old Man saw would have probably been caused by software not the GPS itself. Modern car gps is quite intelligent to the point if you drive through a tunnel it will "forecast" your location in the tunnel until you pop out the other side based on your current speed etc. This software in most cases will have the posted speed for a given area stored with its maps. The problem with these is they are quite often wrong and don't account for traffic road works weather and my tendency to sit a couple of KPH over the speed limit. I think on my last drive to North QLD from Brisbane my car GPS (Tom Tom) overestimated the trip by 3 or so hours.

 

I have no real exposure to aviation GPS as yet but it would be my assumption that all its calculations would be made real time keeping the data given to you quite accurate based on your current situation.

 

But I am not sure how many people remember what GPS was like in Australia during the Gulf War i spent alot of time on the water during that period one minute your gps would show your location accurately and 30 seconds later it would have you 5 miles inland . I would never bet my life on GPS alone.

 

Still a great toy

 

Marc

 

 

[fly_tornado]

has there been no development of GPS systems since 1991?

 

 

[facthunter]

I have flown with a navigator using sun moon or stars , used drift meters, 3 x inertial , GPS, and done a lot of relying on good compass adherence to track. time keeping and ded. reckoning There are no roads in the sea and no roads in the sky The GPS looks like the greatest thing since sliced bread. One day when I was legal for visability but not by a lot, the screen says. "failed to acquire satellites". what would have a stress free ride suddenly got harder. Never take it for granted and it is not a substitute for proper planning. I expect as time goes on it will be harder to get this message across. On instrument using ground aids you never rely on just one where the situation is critical. To do an autoland you have two autopilots and they have to agree.

 

Ships would have the latest in duplicated technology but they still end up on reefs frequently. Utilise everything you have. don't get me wrong. I love my GPS's, but don't let them make you lazy or complacent. Nev

 

 

[dazza 38]

I must be lucky because I have never had a car GPS say "failed to acquire satellites" and I have been using them for about 8 years. I cannot comment on aircraft Gps systems because I dont own one or use one.

 

 

[fly_tornado]

GPS reminds me of that Internet thing that everyone was hyping a few years ago, it won't last.

 

 

[facthunter]

The aviation ones have the better database (obviously). Perhaps they are more critical of satellite coverage. Mine was a Garmin 296 ( which I like). GPS will be around for a while, and get better and cheaper. Best use is to find where you parked your car. Nev

 

 

[Sapphire]

Yenn said: "I am Borg-I never get lost" Sapphire, I don't understand this quotation, maybe you can enlighten me. My name is Borg and I can't say that I have never been lost

 

Watch Star Trek. If you are Borg you have artificial implants when you were "assimilated" Borg are part of the "collective" which means they think as one. Do you qualify? [probably do if you are married]

 

 

[motzartmerv]

Seeing as this thread is in the student section I will try and be pretty black and white. Unless your GPS is Tso'd 145 (or what ever it is)and your logbook is stamped good to go on that type, then it can NOT be used as a primary means of navigation.

 

Your maps sitting in the back or in your pocket while you blunder along using your ipad or any other non tsod navigation device, does not make it legal. The rules are changing (i believe) but havnt yet as far as Im aware. So map up people, sure run your gps to lighten the load, but maps are it for the time being..

 

 

[Gnarly Gnu]

GPS isn't so trendy any more it seems. Next, fresh interest in the sextant?

 

What's a hit with hip young travelers? Fold-up maps

 

 

[Guest Howard Hughes]

Not aviation related, but relevant to the topic.

 

Three years ago I visted my Mother and Father in Melbourne, where we were off to Clarendon St, South Melbourne for lunch on the tram restaurant. My father had his brand new GPS which he was keen to impress me with. Keeping in mind my father had driven trucks around Melbourne for over 40 years, we set off on our journey. I was sitting in the back and thought the route being taken seemed a little odd (I had also driven both trucks and taxis around Melbourne), but not wanting to dampen my fathers delight with his new toy, said nothing. Finally the GPS announces "you have reached your destination". When we look around there is no tram restaurant to be found and it turns out we are in Clarendon St EAST MELBOURNE!

 

After some discussion it would seem my father had entered the wrong suburb. I asked him "didn't the route seem a little strange to you?", to which he replied, "yes, but I thought the GPS new better".

 

From this incident there are three important things to remember:

 

1. GPS's are machines and are only as good as the information entered by the operator (ie: crap in, crap out)

 

2. If your experience is telling you that something is not quite right, listen to it!

 

3. If you are ever a passenger and something doesn't look right, SPEAK UP!

 

Although the only outcome for our trip was being a little late, in aviation the consequences are magnified.

 

PS: In the Kingair we still carry the latest WAC charts. I often get them out and practice my map reading skills, it's amazing how accurate you can be with your times!

 

 

[fly_tornado]

old people + technology = fail

 

 

[Sapphire]

All my car gps's have failings. One always tried to take me off the hwy at the same place every time and another time went north instead of south. Another got completly lost in the country.That is rare and an inconvenience unless you are flying.

 

 

[Guest Howard Hughes]

old people + technology = fail

I think it's a little more complicated than that FT!

 

 

[Sapphire]

I think it's a little more complicated than that FT!

 

 

Lets make it more complicated [standard procedure] technilogically challenged people + technology=failure

 

 

[Guest Howard Hughes]

To further elaborate, despite their age neither of my parents are 'technologically challenged', in fact quite the opposite. I was pointing more towards the 'human factors' elements of using technology. I have watched on as pilots with tens of thousands of hours enter erroneous information into an FMS (which is for all intents and purposes a fancy GPS) and then proceeded to follow erroneous information. Without cross referencing (checking) all the technology in the World is useless!

 

 

[cscotthendry]

I look at it this way:If they only ever taught you to do arithmetic using calculators at school, what would you do if there wasn't one handy, the battery went flat or it was just plain old broken?

 

As for using the GPS as the primary source of nav? Again, I'm of the opinion that if you're able to track your position on the map in parallel with the GPS, why not use the little purple line for all it's worth. After all, if I've got to do some arithmetic and I have a calculator handy, why would I go the pencil and paper route?

 

 

[peter]

Sextant used during daytime (sun fix) produces a line of position, not a fix. To get a fix you must add DR, total accuracy from a small platform, lucky to get within 5nm. Running fix using map and compass from an aircraft, probably several nautical miles, direct map to ground immediately over a known feature, probably a mile. GPS accurate to 30 metres. I'll take the GPS thanks.

 

Map to ground gives you an indication what cross wind you have been flying in, glance at GPS and you get real time information, I'll take that thanks.

 

to get accuratE chart fix needs head focused inside cockpit, accurate GPS fix occurs with my head focused outside the cockpit, I'll take that thanks.

 

Flying down final, quick comparison between IAS and GPS ground speed then glance at windsock and you have a guide to expected wind sheer , I'll take that thanks.

 

Do I carry charts, you bet, I love them, they are fabulous for getting an overall perspective. Do I use my GPS, you bet.

 

which one is "primary", who cares! I use both.

 

peter

 

 

[Sapphire]

Do I carry two gps's-I'll take that thanks. Can I ever get lost, you bet. Who cares,me

 

 

[Jabiru7252]

not that you should ever not use maps, but to play the devils advocate (bare in mind my very limited experience) surely there is a huge difference between using a car gps and an aviation gps?

I use a car GPS (Garmin Nuvi 255W) in off road mode. Works a treat. Draws a pink line from A to B and as I fly, I leave a little blue line. I can see at a glance if I am on track, how far to the next waypoint and my speed etc. (albeit in kph). A great little backup system, I use the map and compass as my primary navigation and can only blame myself if that lets me down. By the way, the GPS track can be loaded into Google Earth after a flight and played back, quite neat.

 

 

[motzartmerv]

Do I carry two gps's-I'll take that thanks. Can I ever get lost, you bet. Who cares,me

Do I ask myself questions and then answer them...Sometimes....hehehehe

 

 

[johnmon]

Ok so what G.P.S. would you all go for. Say up to $1000.

 

 

[cscotthendry]

Ok so what G.P.S. would you all go for. Say up to $1000.

For that money, I reckon you can't go past an iPad 3G mini with OzRunways. You get a GPS and a lot more for the $$$.

 

 

[metalman]

I always have a map, and a GPS ,,,and an iPad with ozrunways,,,,the map has never failed me,,not even once ( although I have failed the map ) the garmin 495 has never failed me ,although I look at the little basta2d with distrust , the iPad with ozrunways is a toy and nothing more, I have it and I look at in flight but it freezes up regularly and needs a restart often enough to be considered as a novelty and nothing more,,,,,in my opinion

 

 

[cscotthendry]

Mm:

 

Interesting comment on the iPad. Mine hasn't frozen...yet. I also carry maps (primary) and a Garmin 495. In any case, my reccomendation should have carried the obvious caveat that an electronic device of Any kind should Never be the primary nav reference. But for $1,000 for a 'backup' nav device, the iPad is far better value than the Garmin.