GPS/NAV Switch

[ardypilot]

Am I right in thinking that by simply flicking the GPS/NAV Switch over to GPS, then hitting NAV on the autopilot panel, that the autopilot system will follow the GPS flight route programmed into the default flightplan?

Also, what does the number in the blue box I have highlighted represent? It dosn't appear to be a heading of any sort?

[Dan]

You are right. I've always thought that this was Microsoft's answer to complex RNAV systems so simmers could use it with out too much fustration - until I was show a new Cessna 182 with a similar feature.

[ZK-KAG]

Yep you are correct.

That blue number is the distance to run to the next way point as far as I know

[Kelburn]

Just what I was gonna say pitty there is no NM beside it.

[ardypilot]

Sweet as, this is going to make long distance flights compleatly do-able now!

I know this will be slightly unrealistic, but I now can do some real long haul flights across the globe without having to change heading manually

[SUBS17]

Theres nothing unrealistic about it as thats what they do IRL but it isn't accurate enough to use for an approach as I found out yesterday with Quito approach on FSX. Auto pilot rocks in FSX.

[benwynn]

you could always buy some payware Trolly

[Timmo]

It certainly is easy....and that is why it isnt used as the primary navigation tool. Its far too easy to indavertently input a wrong coordinate etc and get totally lost (but still know exatcly where you are )

At least for real world VFR flying, GPS should only be used to confirm your own navigation....Im fairly sure its the same for IFR- It is not a tool that is relied apon.

[SUBS17]

Thats because GPS is quite unreliable but the new European/Russian GPS systems will be better if they get enough sattelites in the air you are less likely to find the system deliberately made inaccurate in times of conflict.

[Timmo]

GPS is actually very reliable- more so when you have some altitude. Innacuracy and loss of signal comes about from interference from hills, vegetation (although many of the newer receivers run an upgraded receiver chip which is far less suceptible to this), multipath errors (the signal bouncing off buildings etc- this can be minimised with software algorithms) and atmospheric differences (this is the main source of GPS innacuracy and is usually reduced by using real time or post processed differential correction)

Deliberate reduction of the signal (termed selective avaliability) was turned off after the first Gulf war- Back then the whole constellation was degraded resulting in all GPS location information being degraded. The US military actually uses their own GPS constellation now AFAIK but can also degrade the accuracy for civil GPS just over a particular area...ahem...ie The Middle East.

Higher end airborne and car navigation systems are also tied into an intertial navigation system as well so if the signal is lost, for example in a tunnel, the position can still be calculated with a fair degree of accuracy.

I think most of the problems are users thinking 'Ive got a GPS- Ill always be able to get home' regardless of weather etc and then promptly flying into a hill or running out of fuel etc

[ardypilot]

Ah well, it seems to be working for me

I set up took off from Amsterdam at lunchtime, went out with my mates, just got back and am currently 1125 nm out of St Maarten at 35,000 feet above the Atlantic. Only 2 hours and 20 minutes left!

[ZK-Brock]

Yip, it's basically doing what they do in airlines, where they have a route programmed into the FMS and have the autopilot follow that track via the waypoints.

[victor_alpha_charlie]

They don't just do it in long-haul airliners, I know for a fact that it is done in VAC. I did notice it said RNAV on the EFIS screen while we were doing it, so know I know what it means! It's a handy thing to know on FS!

[cowpatz]

GPS is fully approved a a primary means of navigation and you will see many aerodromes that utilise it for approaches.
Cheers
Steve

[scon]

I came back from Whakatane in our (Auckland Aero Club's) Cirrus SR20 and used the GPS/Autopilot all the way home untill about 15NM out of AR

[Finatic]

I've found getting the hang of navigating via the gps and using AP to be a god send!

I've only been using it for the past week or so... Before that I was only flying very short distance flights and circuits, because I was getting extremely frustrated trying to get the correct trim and power settings to attain level flight. I'm still practising manual flying though because where's all the fun in flying AP all over the place?

Was great flying Auckland to Nadi, Fiji using AP assistance... until I crashed on landing that is. LOL (Mind you, it was my first attempt in a 747)

[G-HEVN]

One RW flight in G-HEVN, I was trying to get a bearing against a VOR on the RMI, and even though I'd tuned and idented it, I just couldn't centre the needle... until I discovered the Nav/GPS switch was set to GPS! (I didn't have a plan loaded into the KLN94 GPS). That was a TB200 Tobago.

[ardypilot]

QUOTE

Was great flying Auckland to Nadi, Fiji using AP assistance... until I crashed on landing that is. LOL (Mind you, it was my first attempt in a 747)[/quote]
It happens to us all mate- the 747 is especially deceptive with its cockpit height off the ground and it took me a lot of practice untill I got the hang of it!

Seeing that you are only just figuring out how to use autopilot, I'm not sure if you are familer with ILS approaches or not but it may help you to read this thread: http://nzff.org/forum/viewtopic.php?t=1029