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TiggCJ

What does the NAV button do?

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Hi everyone, This is my first post in the Flight Unlimited Series forum. I have had the sim for about a year now and I have figured out pretty much all of it. But what (you can probably see from the title) does the NAV button do? I know the APR button engages to the ILS and lands for you, that's nice, but is the NAV for the NDB or something? (I have been told before that you can get an auto-pilot to follow an NDB, but I tend to just follow it manually.) And what do you do when the controller says "cleared to transit my airspace at (e.g.) 1500." Do you wait until he says something or when you've reached that altitude can you just change the frequency? (I get a bit annoyed when departing Renton Municiple (RNT) and he tells me to contact Boeing Field Tower not Seattle Approach...!) If anyone can help me I'd be most grateful! Kind regards, TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi, and welcome.Blimey it's quiet here now isn't it?I'm ashamed to admit my FU3 is now in a zip file on a backup drive.The NAV button, if it's working correctly causes the autopilot to fly your plane to or from a VOR on the radial selected for VOR1 on the HSI. Be aware that in the outer terrain at least, the VOR beacons don't necessarily match the locations shown in the in-game map.Fly at 1500' if tower tells you to. He'll hand you on to someone else when you leave his airspace. If you're being handed on to another tower controller rather than back to Seattle Approach it's because two tower airspaces are contiguous. At the end of the chain you'll be back to Seattle Approach.You can ignore him if you like by adding (I wait to be corrected because this is from rusty memory) something like No Tower on Guard to the main config file (fu3.cfg?). I think it may already be in there but //commented out or ;commented out.Kind regards,D

Edited by Dave_Morgan

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Hi there Dave, Very helpful, thanks! Could you explain quickly what HSI, VOR1 and VOR2 are? Also, what has an ADF got to do with VOR's? Just to slightly change the subject for a moment, If anyone out there knows specifically about the Muskrat, I can't figure out rudder on land! Water, absolutely fine, but on land I slam on the rudder pedals and turn the yoke which ever way but it turns ever so slowly or not at all... can anyone help? Back to the VOR thing, is the purpose of a VOR to lead you to the main airport in a certain area?Thanks again ,TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi again.HSI is Horizontal Situation Indicator. That's the compass gauge in the 'big six' main gauges. It usually has two knobs with it...One of them can alter your chosen heading if the autopilot's HDG button is switched on. It moves a small pointer (usually pink or orange) on the rim of the display. You can move the pointer with the knob and in HDG mode the autopilot will fly the plane towards the heading shown by the pointer.The second knob turns the split yellow arrow. Turn the arrow so that it points to the heading of the VOR radial you want to follow. Set the autopilot to NAV mode and the plane will fly over to that radial then follow it. So if you want to fly on a heading of 195° from the VOR at SeaTac tune NAV1 to 116.80 (I think that's the correct frequency) and turn the split arrow to point towards 195° on the HSI. In NAV mode the autopilot will fly across to that radial then follow it.The middle piece of the yellow arrow lines up with the head and the tail when you are on the radial. If you are on R-195 and you turn the knob so that the split arrow points towards 205° you'll see the middle section is misaligned again. Which side it has moved towards will indicate to you whether you need to turn left or right to get onto the new radial.Most big airports have a VOR beacon on the field but you can use NAV1 and the NAV mode to fly towards or away from a VOR beacon. Note that the plane will not distinguish for itself which way you want to fly- either towards or away- but will pick the direction that requires least adjustment, so you'll have to be going in approximately the right direction to begin with.We're all taught in Scouts or Cadets to fix our position by taking a bearing from say a church steeple and another from a prominent hill top, and drawing the bearings backwards on a map to see where they cross. You can do a similar thing with NAV1 and NAV2 to fix your position by finding the bearing from two different nearby VOR beacons.ADF is another navigation aid. It's something like Automatic Direction Finder. It is a gauge that uses a simpler type of beacon, the NDB. That's Non-Directional Beacon and so called because all you can do is fly towards or away from it- you can't choose a radial and expect the autopilot to find and follow that radial. You can do it yourself but it takes a bit of thought.As I recall, the Learjet has all four indicators (heading bug, split arrow, second VOR arrow and ADF) all on the HSI. Other planes may have them split between several gauges.ILS, instrument landing system, beacons use the VOR1 receiver and either show up on the split arrow on the HSI, with a small marker on the side of the HSI to show whether you are too high or too low, or show on a separate gauge on which you have to keep two crossed white lines centered.I couldn't tell you about steering the Muskie- that was never one of my favourites. I found lots of much nicer planes and repaints in the library here. Does steering with the rudder while taxiing work ok for you with other planes?Cheers,D

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Hi again Dave, Very interesting! Thank you!I will practice that VOR thing and have a play around. I thought it was the double blue arrow for VOR's? When you say the split arrow, do you mean the double blue arrow (on an HSI)? I will also practice the white line thing. When they are both centered, will the little icons at the side both say 'on'? I gather that the ADF just works with the NDB then? Thanks again, TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi.

I thought it was the double blue arrow for VOR's? When you say the split arrow, do you mean the double blue arrow (on an HSI)?
As with a lot of stuff, a picture is much better...http://en.wikipedia.org/wiki/File:Horizontal_situation_indicator-en.svgAlong with Google, Wikipedia is your best friend. The split arrow, in the picture in the link, is part white and part yellow. It's labelled 'Course Select Pointer' and Course Deviation Bar (CDI)'.For ILS, you could do worse than to read this:http://www.navfltsm.addr.com/ils.htmor at least to look at the pictures.Cheers,D

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Thanks Dave! I recognize the split arrow now from light aircraft, but on the Beechjet and bigger aircraft, is there a different instrument or a section of the HSI that you can see for a VOR? And what is the difference between VOR1 and VOR2? Cheers, TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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I've had a go and it seems that a blue double lined arrow represents VOR2. There is another arrow that's green. Is this VOR1 or the ILS direction? Also there is another button called VS. This turns on automatically when the APR button is on. What does the VS do then? Thanks, TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi.From memory (remember I don't use FU3 any more) the split pointer for VOR1 is green, VOR2 is the double blue arrow and the ADF uses the red arrow. The functions are replicated in the two green glass-tube gauges on the left. You can switch their displays between NAV1, NAV2 and ADF (ADF is the gauge that responds to a NDB).You use NAV1 for VOR1 and ILS, and NAV2 for VOR2. That means VOR1 and ILS will show on the split arrow, and VOR2 will show on the blue.VS is the vertical speed hold on the autopilot. In approach mode (APR), when it's following a localiser and glide slope, the autopilot has to control the vertical speed to keep the aircraft on the glideslope so it switches that on automatically. You can use it yourself in a climb or descent but be careful not to let it go on too long if you are climbing. As the plane reaches its ceiling it won't be able to climb that well but the autopilot will still try to maintain that VS by trimming more and more nose up... until the plane stalls.Regards,D

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Dear Dave, Cheers!So how do you get between NAV1 and NAV2? Thanks,TiggCJSorry, one more thing (I'm full of questions!!) if you want to fly the ILS manually, you would obviously tune to VOR1 to get the green arrow, OK. But where does it give you Glide Slope information? TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi.I'm not sure what you mean by 'between NAV1 and NAV2' but you can have two different VOR beacons tuned (in the Beechjet you tune with the push-buttons by the side for the frequency display. I think either Tab or Enter cycles between them too. I also think you can just click directly on the frequency display. It's been a long time. On the Beechjet's green gauges, I think there were click-spots on the lower corners of the gauge.Glide slope info is shown by the Dual Glideslope Indicators in the picture I linked above. A similar thing shows on the side of the Beechjet gauge (tiny white arrow-head slides up or down a short line of white dots, as I recall). I think maybe the glideslope beacon (same frequency as the localiser, and both picked up together by NAV1) has a shorter range than the localiser. It won't register until you are within a few miles of the threshold, while the localiser registers from about 20 miles. As a rule of thumb, pick up the localiser at about 20 miles out, and unless terrain is going to get in your way, try to be at 2500 - 3000 feet above threshold elevation at 10 miles out, and already in line with the runway. If you're already lined up a long way out it makes holding the approach much easier.I have a vague memory of a few outer terrain airports having different ILS to the frequencies shown on the in-game map, which caused me no end of confusion in my early days...I might drag my installation out of the archive tonight, just for old time's sake.Cheers,D

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Hi Dave, Thanks again! Yes you're correct, there are buttons on the lower corners of the Beechjet's green dial. That's probably where you switch then! Does VOR1 take you towards the specific airport and VOR2 take you away from it? Is that why there are two VOR's? If that's not it, then why the two VOR's? Cheers, TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi.Lol. Stop thinking about airports. The beacons could be anywhere...I knocked the following up for you last night.The frequencies on the radio tuner, sort of bottom left of the screenie, from top to bottom are comms, NAV1, NAV2, ADF and transponder. Click on one of the numbers and it becomes editable. Hit Enter or Carriage Return when you're done.We're lined up with, and approaching runway 27. That's confirmed by the HSI, which shows the plane heading about 274° (just past 'W').From the bottom of the radio tuner working upward...We're not being told where to fly by any ATC, just flying around, so the transponder is set to 1200, the standard code for a VFR flight. If we had filed a flight plan, or wanted a flight following service, we'd have been told to '...squawk XXXX...' and we would enter the number XXXX in the transponder so ATC could identify us.The ADF is tuned to a nearby NDB, frequency 371 MHz, that I placed at the outer end of the glideslope a couple of years ago so I could fly directly onto the glideslope. The beacon is about 10 miles from the airport, and is 8 or 9 miles behind us, as you can see on the GPS. The red arrow on the HSI points towards the NDB, directly behind.NAV2 is tuned to a nearby VOR beacon, frequency 116.00 MHz, and is shown on the HSI by the double blue arrow. The blue arrow is pointing towards 064°, the direction of the VOR beacon. The beacon is not very far away, as you can see on the GPS. There's a small fault with the GPS in that beacons show up with magnetic headings, and airports with US national grid headings. It always took me a moment or two to work out which way to turn...The ADF and NAV2 information is repeated in the DME (distance measuring equipment), the green gauge to the left of the HSI. I've set the single arrow to ADF, and it shows the direction of the NDB, about 091°. I've set the double arrow to VOR2, and it shows the direction of the VOR beacon to which NAV2 is tuned. In the middle of the gauge are four numbers: 1 & 8, and 2 & 2. They show the beacon on DME 1 (ADF in this case) is 8 miles away, and the beacon on DME2 (VOR2 in this case) is 2 miles away. The round buttons in the bottom corners of that gauge are the click spots and will switch between ADF & VOR1, and VOR1 & VOR2.NAV1 is tuned to the ILS RY27, frequency 110.10 MHz, and is shown on the HSI by the split green arrow. I've aligned the arrow with the runway. You do this by left click-and-dragging the CDI button just beneath the HSI. The centre section of the arrow is slightly off centre to the left, showing we need to be just a tad further to the left to be aligned properly.We're not using the autopilot to follow a heading so I've turned the red heading bug round to 315° out of the way by dragging the HDG button. The heading I set is shown in red just above the HSI. The green information relates to NAV1, in this case the ILS. It shows I've turned the arrow to point to 273°, the runway heading, and it shows we are 1.5 nautical miles from the beacon.Immediately right of the HSI is the Vertical Speed Indicator. Here we're descending rather fast as our vertical speed is -1.4, which is to say 1400 feet per minute downward.The whole glass tube gauge, of which the HSI is a part, is called the Primary Flight Display. In the Beechjet it's a combination of HSI, VSI and the following:Attitude indicator (AI), the brown and blue squareAirspeed indicator (ASI), the scroll on the left currently showing a very fast approach speed of 176 knotsAltimeter, the scroll on the right currently showing 1360 feet above sea levelGlideslope indicator, the green diamond on the right edge of the AI. The diamond shows the ideal position for the plane. It's above centre in this case, showing we are too low.RA and DH above are radar altitude, 277 feet above the ground, and Decision Height, turned off because we're flying in good weather.On the whole I'd prefer to go around and to try again as we're very low, very fast and descending much too rapidly but the picture illustrates some of the things you've asked about.Don't take the following as patronising; you might have 30 seconds' fun with it...In the second picture we are 19 nm from the VOR 116.80 at SeaTac on a heading of 260°. That's shown by the split arrow in the HSI. The small white triangle at one end of the arrow points towards the beacon (or at least to the half of the compass in which the beacon lies). We are also within range of another VOR, 109.60 MHz, to which NAV2 is tuned. That beacon is at McChord AFB. Its direction is shown by the double green arrow and is about 131°. Our Mooney is pointing pretty well 015°, is not moving and is at about 450 feet ASL. From that you should know where we are... the in-game map is adequate.I hope this has helped a little.D

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Hi Dave, Yes, it's helped a lot, cheers!! I guess you still enjoy FU3 then? Was the airport in the Beechjet Yakima Air Terminal by any chance? If so, how did you get that airport? I don't have it...Talking about the RA and DH, how do you turn them on? Or are they automatic? Also the GS diamonds, I guess it's opposite, so if it's the higher two you're too low and the lower two you're too high, right? Thanks again, most appreciated!TiggCJ


Why are graphics so important? They've made me crash... or is it just my computer? ^_^

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Hi.I don't use FU3 any more. I had a good modded copy zipped up on my external hard drive. I just took it out briefly last night to make a couple of pictures.Good guess. Yes, the airport is Yakima. It's in the library here. You'll need a complete installation of FU3 with the full outer terrain already installed in order to use it. It works best if you also use a few other packages from the library. Instructions are in the readme for each download.Radar altitude is always on. It helps a lot when you are trying for very smooth landings.Decision Height is something you set as a reminder when you are making an ILS approach in poor visibility. It gives a warning when you are at the set height above the ground. That will be the point at which you decide whether or not to land, based on how clearly you can see the runway. The height that you set is taken from the relevant approach plate for the airport.You're right about the glideslope indicator. It shows, like the CDI on the NAV1 display, where you ought to be.Have you worked out where I took the second screenie?D

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