NAV1/NAV2/GPS--Help me out to clarify

[Doum76]

Greetings all,

With fgrimley32's «package» for the new F/A-18 HUD, and my few last days learing also the Aerosoft F-16 HUD makes me come at a point trying to understand the NAV1/NAV2 Options, even the GPS one.

I rather ask the question here, since lots of people here like Spaz, Microbrewst and Spaz comes out with real life info which is pretty darn good.

At first i thought NAV1 was a setting of the Localizer and Glideslope frequency/course selection for exemple, Waypoint 1, NAV2 for Waypoint 2.
But with the Panel from the HUD settings (SHIFT-2) newly added to the F-18, makes me realised that setting up NAV1 will gives me the
«steer point arrow» which is mostly the same that appears on default F/A-18 HUD when selecting TCN on the HSI. And setting up the NAV2 with the same frequencies and course selection, will add the NAV Steering cue (little circle with the line tail). And there is the GPS on the switch also which i have not a clue what it is for, besides setting up a flying path. My question, what exactly are the NAV1 versus NAV2 and versus GPS.

Clearing this out might help me understand why on the F-16 i cannot get the NAV Steering cue nor the Sterring point on any of the NAV1 or NAV2 switch, only on the GPS switch.

[micro]

Hey, Doum. Thanks for the compliments. What that switch does is allow you to bring up steering information on the HUD from those three different resources. If it showed all three at once that would become very confusing. For example, if you have "Station A" tuned in on NAV1 and "Station B" tuned in on NAV2, and you have NAV2 selected your HUD will display the information for NAV2 only. The same thing goes for GPS. Also, the switch tells the autopilot which resource you want it to use in the "NAV" autopilot mode. So, if you have your flight plan all layed out in your GPS and want the autopilot to track it, you would have to have that switch in "GPS".

So, in short, the way to use that switch at any given time is to ask yourself, "what am I using to navigate?"

Having said that, remember that these "simulations" are becoming rediculously realistic. Just like in the real jet, one switch in the wrong place can screw everything up. That would be my guess as to why you're not getting a steering cue. So, just like in the real jet, know your "switch-ology". 

[Doum76]

Well thanks for the reply,

I rather ask the question here, since lots of people here like Spaz, Microbrewst and Spaz comes out with real life info which is pretty darn good.

I realised i mentionned Spaz two times,  in case his ego gets high a bit, i say first, i intented to mention Jimi in those 3 names  , lots of other people here knows their stuff, but you 3 guys are the ones that post, replies the most.

Well it's tougher to understand specialy since the mod HUD is not fully operation with the F/A-18 from Acceleration, since the Hornet doesn't support more than one NAV on the HSI. For Exemple.

I use 2 airports nearby my home, (CYUL, CYMX) they are pretty much close to each others, has PAPI4 runway, no PAPI runway, it's great for practicing flying using the HSI with Course Selection Bug, Course Selection Deviation arrow to locate the airport, line-up (much easier now with this HUD also), landing with the ILS Bars on a runway w/o the PAPI4, landing w/o ILS Bars on a PAPI4 Runway, etc...

So far only i found to be working good with the added HUD if using a Flight Plan, is for exemple in the Flight Plan select as starting point CYUL, destination CYMX. Once in the a/c, on the HSI i click on the Waypoint OSB, but in order to land and have ILS Bars on the UFC ILS i set up the frequency for CYMX (110.90) on the SHIFT-2 panel for NAV1 knob en enter the Course Selection 113 deg. (since the only knobs that affects the Deviation Arrow on the HSI is the NAV1 knob, i find the knob faster to set than using the swith bellow the bingo/fuel knob) On the SHIFT-2 panel i set the GPS/NAV switch on GPS to be able to use the flight plan. I set the Steer switch on NAV2, for some reason, the only way to get correctly the Deviation Arrow on the HUD and stay there is to select NAV2, which the NAV1 knob seems to act to set up the deviation arrow on the HSI and the NAV2 knob sets the deviation arrow on the HUD. Once ready to land, i click on the SHIFT-2 panel the NAV/GPS switch and set it up on NAV, it makes the ILS bar and Steer point appear (if the ILS switch on the same panel is set on the second position)

Makes me ask you a few questions again, sorry for all those questions, but i gotta admit, aviation is a huge thing. 

First, is the Steer Cue (little circle with the tail) only used for azimuth purpose on landings, if not, how come i don't alway get it, and only appears in certain time. The arrow showing on the HUD, is it a deviation arrow like the HSI supposed to always shows, or is it the TCN arrow, showing on TCN selection and goes away when on ILS bars appear. For exmple with the mentioned destination, the Steer Cue only appears once i passed the emitter or the start of the runway, does it only show when facing the runway and not back or passed it?