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hi alli listen to my scanner sometimes and i have heard ATC tell aircraft different approaches the three i have heard are1/ Expect ILS approach to runway 012/ Expect VOR/DME approach to runway 013/ Expect Visual approach to runway 01can anyone tell me what the main differences are between 2 and 3, i pretty much know what 1 meansthanks!

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Hi,ILS stands for Instrument Landing System. An ILS will give the pilot lateral (horizotal) guidance as well as vertical guidance. This combination is known as a 'precision approach'.To get lateral guidance a localizer (also known as LOC), which is a transmitter, usually positioned at the centerline of the opposite runway end, sends two beams horizontally in line with the landing runway. An indicator in the cockpit with a vertical needle, which moves left or right tells the pilot which way he should fly. When the needle is centered, the aircraft is on the extended runway centerline. If the needle is deflected, say to the left, the pilot should also alter his course to the left until the needle is centered again.In addition to provide vertical guidance a glideslope (G/S)is used on an ILS. The glideslope transmitter is usually located on the side of the runway at the touchdown zone. About 1000 ft from the threshold. The glideslope normally will provide a 3 degree descent path to a horizontal needle in the cockpit, which will move up or down. Again, if the aircraft is, say too low, the needle wil deflect upwards, telling the pilot to fly upwards until the needle is centered again. Note that the glideslope is usually captured from below. This means that the aircraft should fly level at a given altitude until it intercepts the glideslope. It should then commence a decent which should guide it down towards the runway.Now for VOR/DME. VOR stations are normally used for enroute navigation. (airways) Sometimes a VOR at or near an airport can be used for lateral guidance during an approach in a similar fashion as a localizer. However VOR will never provide vertical guidance. Hence the term 'non-precision approach'. DME stands for Distance Measuring Equipment and is just that. DME will give you the distance in nautical miles from its station. Usually DME can be co-located with VOR or LOC transmitters.A visual approach is flown by looking out the cockpit and aligning the aircraft for landing by eyesight.Hope this helps.

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This brings up one of my wish lists for FS2004.It would seem microsoft could easily incorporate ASR and PAR IAP's into the ATC bundle.If you do not know, a ASR approach is where ATC directs the airplane through the approach (i.e. turn 5 deg left, right, etc). A PAR is pretty much the same thing, but incorporates vertical guidance also.Anyone else interested in this? Anyone ever done a PAR in real life (I've done numerous ASR's but no PAR's)?

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Guest CYOW_pilot

ChickenHawk, I've done hundreds (or more) of PARs in real life (as a military pilot) but on any given day I would much rather shoot an ILS for various reasons (especially if the the weather is crap). A PAR adds another element that can go wrong (ie the controller having a bad day, controller skills can be quite variable depending on what country and even what service such as Air Force or Navy, or the weather affecting the quality of the radar picture). On an ILS, I can see any deviations from the GS and LOC immediately and make a correction based on the size of the deviation. On a PAR I have to wait for the controller to notice the deviation then transmit a correction and then wait for them to tell me how the correction is working. On in all, it is much easier and faster for me to follow the ILS signals. Besides, pilots are control freaks and why give someone else control if you don't have to ;-)PAR is most likely on the way out, at least up here in Canada, except for some training and deployed military operations to austere fields. All our aircraft (the Canadian Air Force) have ILS equipment. The ground based ILS equipment is cheaper to maintain than a radar and you don't have maintain a large pool of expensive radar controllers.IMO, I don't think adding a PAR capability to FS?? would be an worthwhile investment of time and effort. Then again, I am one of those guys that never flies (in FS2K) with the ATC turned on and have no desire to fly with VATSIM. ATC can be a pain in the butt in real life (but very necessary, I know, I know) so when I get a chance to fly around in FS2K without ATC and provide my own vectors and clearances (no delay expected, cleared direct!)I go for it.Cheers,Kevin in CYOW

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KevinThank heavens for PARI was low on fuel with a jammed fuel selector and unforecast fog covering an extensive area.I was talked down into a military base which was colour code red with 400 metres vis and an overcast cloudbase just above the hangers at around 80 feet.The base was Shawbury in the UK and the controllers were brilliant continuing intensive corrections below the minima of 200 feet.Seeing those runway lights was a reliefIt was that or run out of fuel ;-)Peter

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hi cmaa i live at calamvale in brisbane (near sunnybank hills) and i am under the path of the ILS for runway 01, they fly right over my roof and turn to intercept for final at Archerfield ADF, but what i have found interesting, is that when the winds are from the north, and 01 is in use, at around 7pm onwards on sunday night **always** i hear the aircraft doing the Moovi 3 arrival which is the STAR for runway 01 with a/c coming from the south (sydney) and southwest (melbourne) i am puzzled to why during the day in excellent weather they do visual approaches to 01 and then after around 7pm sometimes 6pm, they fly over my house doing ILS to 01, the weather is still fineregardsClayton

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Hi Clayton,Right under the approach path, nice place to live hey? I used to live next to the OM for RWY16R at Sydney and it was plane-watchers paradise. (Now in 'Sunny' Melbourne)The reason for the ILS at night may be due to visibility reasons as it approaches last light, so they follow the ILS approach till they are well an truly visual with the runway approach lighting system. When flying at night it's very easy to confuse the lights of the city with the airport, especially if one is not familiar with the area such as in the case of the international arrivals.Cheers,Fermin - fsadventures.net][/b

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ah ha i seewell its a humid sticky day here in brisbane today, as i type this a Qantas 737 is flying over my house ILS 01!

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Guest artl

The posters have more or less covered it, but here is one additional point. The VOR approach, because it does not have glideslope assistance, is normally flown by descending "quickly" to the minimum altitude (after passing the published final approach fix), then flying more or less level at minimum until the runway is visible... using a timed interval ( or a DME, if available) . If the runway is not visible at the end of that period, it is time for a missed approach.Minimum altitudes are higher because it is not known how fast you are going to get "down" , and they have to be sure that you clear ALL of the obstacles to the runway.Art.

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It could be depending on the operating procedures of the airline. Generally it would be flown via AP inputs and the LOC can be used to track the VOR radial down to the minimum. Don't quote me though...Fermin - fsadventures.net][/b

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Several years ago we could practice PAR's at MacDill AFB on Sundays with our corporate jet. We would be advised at least twice that it would be a low approach ONLY, runway is CLOSED. try lifting the hood at 100 ft. and looking at a 500 ft. wide runway compared to a 200 ft. runway and you will swear that you are a submarine. :-)

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