=4c=Nikola Posted February 22, 2011 Posted February 22, 2011 (edited) The message you have entered is too short. Please lengthen your message to at least 1 characters. Edited June 15, 2014 by =4c=Nikola 1 Do not expect fairness. The times of chivalry and fair competition are long gone.
MadTommy Posted February 22, 2011 Posted February 22, 2011 ^^ +1 Also it would also be nice to get the QFE before you are on the runway, maybe at start up or taxi communication. i5-3570K @ 4.5 Ghz, Asus P8Z77-V, 8 GB DDR3, 1.5GB GTX 480 (EVGA, superclocked), SSD, 2 x 1680x1050, x-fi extreme music. TM Warthog, Saitek combat pro pedals, TrackIR 4
aaron886 Posted February 22, 2011 Posted February 22, 2011 A military air traffic controller from here in the states would say something like, "Hog 11, cleared to land Runway 09, winds 159 at 9. Check gear down." (Or at least, that's what the last military airport I flew an approach at said.) Altimeter settings in the US are always what you call "QNH," giving altitude above sea level once corrected. If they gave the altimeter with a clearance, which isn't going to happen because we use things like ATIS, they would read it as inches of Mercury preceded by the term "altimeter" for clarity... so a standard day altimeter would be read, "Altimeter two-niner-niner-two." (29.92 In. Hg.) You'll never hear a controller in the US say "QFE" or "QNH..." just "altimeter." It's assumed to be inches of mercury.
AlphaOneSix Posted February 22, 2011 Posted February 22, 2011 You'll never hear a controller in the US say "QFE" or "QNH..." just "altimeter." It's assumed to be inches of mercury. International airports (or where I am now, at lovely Kandahar airport), you get both values from ATIS...i.e. ATIS will say "QNH one-zero-one-three, altimeter two-niner-niner-two" for example. It seems to me that if the word preceding the value is "QNH", then the value is assumed to be in hPa/millibars and if the word preceding the value is "altimeter" then the value is assumed to be in inches of mercury. I have never ever heard QNH followed by a value in inHg.
effte Posted February 22, 2011 Posted February 22, 2011 International airports which are not frequented by a lot of US military traffic will typically only give QNH, and expect inHg accustomed pile-its to put that expensive training to good use figuring it out. "USAir 123, descend 4000 feet, QNH 1002" "Uuuuh... could you give us that in inches, 123" "Sure thing. USAir 123, descend 48000 inches, QNH 1002" ;) QNH is short for altimeter setting, referenced to MSL, dating back to the good old days of using morse code to get messages across. Theoretically you could give inches HG, mmHG or hPa interchangeably as a QNH. That's not the way FAA phraseology is set up, obviously - and just as well. Reduces the potential for confusion! FAA order 7110: c. Issue the altimeter setting: ... 3. TERMINAL. To arriving aircraft on initial contact or as soon as possible thereafter. The tower may omit the altimeter if the aircraft is sequenced or vectored to the airport by the approach control having jurisdiction at that facility. ... 3-10-1. LANDING INFORMATION Provide current landing information, as appropriate, to arriving aircraft. Landing information contained in the ATIS broadcast may be omitted if the pilot states the appropriate ATIS code. Runway, wind, and altimeter may be omitted if a pilot uses the phrase “have numbers.” When clearing an aircraft from a level to an altitude, the altimeter setting has to be given along with the clearance. I expect that to be a lot less common in the US though, with the TA all the way up there at 18,000. Cannot seem to find a solid reference in the FAA order, so I guess the issue about how it is done on the wrong side of the Pond is still up for debate. :) ----- Introduction to UTM/MGRS - Trying to get your head around what trim is, how it works and how to use it? - DCS helos vs the real world.
aaron886 Posted February 22, 2011 Posted February 22, 2011 (edited) "Sure thing. USAir 123, descend 48000 inches, QNH 1002" Rep! :megalol: When clearing an aircraft from a level to an altitude, the altimeter setting has to be given along with the clearance. That's as I understand it... although I don't do any flying in the flight levels. (Yet.) As you suggested, the only time I know of a controller giving an altimeter setting is by request, or for high altitude traffic that have set their altimeter to 2992. Edited February 22, 2011 by aaron886
effte Posted February 22, 2011 Posted February 22, 2011 You get an altimeter setting when the pressure changes, when handed over to a new controller with another pressure and when cleared down from the levels (even if you can apparently waive it in the US by acknowledging ATIS). About GA and levels... I've been cleared destination, "FL70 or below", plodding along in a puny little C172... with an hour and a half to go. Densely populated area with loads of traffic it wasn't. :D ----- Introduction to UTM/MGRS - Trying to get your head around what trim is, how it works and how to use it? - DCS helos vs the real world.
aaron886 Posted February 22, 2011 Posted February 22, 2011 "FL70 or below" Well that just ain't right... :huh: :D
effte Posted February 22, 2011 Posted February 22, 2011 I do not really see benefit of QFE when you have radar altimeter onboard. Terrain under the approach, RF emissions... radalt isn't the end-all, be-all. ----- Introduction to UTM/MGRS - Trying to get your head around what trim is, how it works and how to use it? - DCS helos vs the real world.
effte Posted February 22, 2011 Posted February 22, 2011 Well that just ain't right... :huh: :D Jeaaaaalooooouuuus! :D ----- Introduction to UTM/MGRS - Trying to get your head around what trim is, how it works and how to use it? - DCS helos vs the real world.
aaron886 Posted February 22, 2011 Posted February 22, 2011 I've taken off at airports higher than your altitude restriction. :D
eedenn Posted March 14, 2011 Posted March 14, 2011 (edited) to answer some questions QNH, or "altimeter setting" is what is used by the military in states. Is there a plan to change the voice comms in DCS to match this? it does affect terrain clearance, level deconfliction from other traffic and altitudes to climb to when trying to hook up with the tanker. Unless ofcourse everyone else is flying off the QFE at YOUR departure point. (unlikely) The altitude you set QNE/ standard/ 29.92 inHg (or whatever you wish to call the transition altitude/level) is mainly for terrain considerations, and sometimes airspace. Spot heights on the charts are based on QNH which is the local altimeter setting corrected to sea level. So it is safe to say that you would need that to know where you are in elevation in relation to the terrain, and whether or not you are above MSA (minimum safe altitude), MEA, MORA, MOCA or whatever is depicted on your chart. Although at times some of the above are given in flight levels. The reason why the transition altitude is 18,000 in the states has somewhat due to the terrain in the mid west. They would rather have a uniform transition for the entire continent vs having one change from region to region, re: europe! QNH in millibars or hPa, not a problem on jets as the altimeter scale has both hPa and in Hg. as for us going to moscow or somewhere in china, we have tables for feet to metric conversion (one for China/North Korea, and one for Russia/Mongolia, as their RVSM levels differ somewhat) but for SIDs (or DP's) and STARS there is a metric to feet conversion on the Jeppessen plates. However we do not base our descent and approach on QFE, we request QNH from ATC. QFE vs radar altimeter: QFE is referenced to a point on the airfield, and therefore indicates your elevation above (or below) that reference only. The radar altimeter however will bounce up and down depending on what is below you. including buildings, trees, birds, other planes or whatever solid strays under the radalt transmitter! You would lose all sense or where the airfield was in relation to you, after you do some maneuvering. hope that answers some questions Edited March 14, 2011 by eedenn Intel i7-980X 6GB 2000MHz DDR3 Windows 7 Home premium 64bit GTX560TI 1GB DDR5 Single Monitor
doright Posted March 14, 2011 Posted March 14, 2011 The number given after the QFE is the .## 29.## or 30.## is assumed. So you would just turn your dial till the last two numbers are what they QFE numbers are. High QFE numbers use 29 low use 30. But yes ATC isn't too accurate. I just set it so altimeter shows field alt. That is what should happen using ATC's numbers. Don't you think air pressure that ATC gives you is not precise at all. I mean, QFE 28, or 29 is useless. For one inch of Hg change, there is almost 1000ft altitude change. This is just suggestion for ED to consider making QFE readings with 2 decimal places (29.92 in Hg for example)...
Bahger Posted March 14, 2011 Posted March 14, 2011 Best M.O. is to note the exact MSL elevation of the airfield you are launching from and set that altitude value in the altimeter before startup. That way you know you have the right altitude setting for the location/pressure conditions. And anyway, does DCS A-10 model variable pressure conditions?
GGTharos Posted March 14, 2011 Posted March 14, 2011 Yes, pressure can change if you use dynamic weather. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
GGTharos Posted March 30, 2011 Posted March 30, 2011 Known bug. So, there is no way to make ATC to read correct pressure with two decimal places like in real aviation? [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
Check6 Posted April 3, 2011 Posted April 3, 2011 Millibars A military air traffic controller from here in the states would say something like, "Hog 11, cleared to land Runway 09, winds 159 at 9. Check gear down." (Or at least, that's what the last military airport I flew an approach at said.) Altimeter settings in the US are always what you call "QNH," giving altitude above sea level once corrected. If they gave the altimeter with a clearance, which isn't going to happen because we use things like ATIS, they would read it as inches of Mercury preceded by the term "altimeter" for clarity... so a standard day altimeter would be read, "Altimeter two-niner-niner-two." (29.92 In. Hg.) You'll never hear a controller in the US say "QFE" or "QNH..." just "altimeter." It's assumed to be inches of mercury. We use HG not millibars as a rule , but some places where foreign crews are training (Red Flag etc) we will issue both . Our standard call on initial contact would be Runway Wind Altimeter Report. So "Hog 11, Runway 27, Wind 240 at 6, Altimeter 2993 , Report 4 mile initial" The gear check is only required by military controllers not civilian controllers to military aircraft. So, as an example I'm FAA now and we control Charleston AFB , we do not say check wheels down.
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