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Epikk

[MD-11] Windshear alert and guidance system simulated?

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Hi, I have posted this question already in the MD-11 question thread, but there is it quickly going out of view, so there is a seperate thread. MD-11 FCOM: "The windshear alert and guidance system (WAGS) provides detection, alerting,and guidance through windshear.On takeoff the WAGS is available from 80 KTS to 1500 feet RA. On landingWAGS is available from 1500 feet RA to 50 feet RA.The WAGS is part of the AFS and gets data from the two central air datacomputers (CADC), the inertial reference system (IRS), and other AFScomponents. The CADC and the IRS can sense windshear conditions and willsend this data to the WAGS. The WAGS will then provide visual warnings onthe PFD and FMA and aural warnings through the CAWS. FD and AP areprovided through the AFS.""The CAWS generates a tone and TAILWIND SHEAR (or HEADWINDSHEAR) voice warning. Windshear modes are also annunciated on the FMA.""When windshear is detected and guidance is active, the system provides FDand/or AP guidance during takeoff and go-around. The system commands a 1degree flight path angle until appropriate airspeed is achieved. The system thencommands pitch guidance to maintain this speed. For takeoff this speed isV2+30. For go-around this speed is GA reference speed +20."Another Addon, the Maddog MD80 from Leonardo simulates this system very well. Here is a short video which shows a TAILWIND SHEAR after take off: http://www.flythemaddog.com/download/video/windshear.wmvJan-Paul

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Hi,the windshear callout is also available at the Freeware MD-11 from Alain Capt www.acsoft.ch When there are sudden airspeed changes during windshifts below 1500 radar altitude, the windshear alert comes active when the speed drops by 15 knots in 1 sec. This has nothing to do with a weather radar, this one can't be simulated due to the lack of weather informations. GPWS Mode 7 description: www.aircraftmech.com/egpws.html#mode7mode7a.jpgSo it is not a problem to simulate this system, because you have the rate of change/direction change from the wind. Jan-Paul

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No, we did not simulate this system and for good reason:FSX's famous and highly unrealistic "wind shifts" do not in any way represent what happens with real world windshear and there is no accurate simulation of it available within the FSX weather system. This would lead to quite frequent windshear warnings which we determined would probably confuse the great majority of our customers into thinking that either 1. they did something to cause it, or 2. they should do something when the warning happens, which isn't true because of how unrealistic the FSX weather is.So just to put to rest any conspiracy theories - yes, we could very easily do this, but as with the wx radar requests, we'd be simulating something that can't actually be simulated accurately due to how FS itself works, and that's not something we're going to do.

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>Yeah, weather radar is another of those "gamy" things having>zero to do with any weather realism in FS. Now you know how>realistic this windshear guidance is.>>Michael J.Yet, I bet you don't even own the product do you? Its very easy to setup a realistic "vanilla" windshear encounter in both FS9 and FSX. There's nothing terribly complex about having winds aloft at 1000ft of 50-60kt and surface winds of only 10-20.A microburst is certainly possible in FSX by creating thermals with negative lift. Whether it would accurately simulate the increasing/decreasing performance resulting from the outflow at the surface, i do not know.The system logic (if done properly) would prevent nuisance warnings associated with wind shifts at altitude. The system is only armed during in certain gear/flap configurations and below threshold RA values. There shouldn't be any spurious windshear alerts at cruise altitude.Nonetheless, the LSH Maddog contains the proper logic for detecting, annunciating, and providing escape guidance for windshear encounters. Thats a fact.And as far as the radar being "gamy"... at least they did what they could within the confines of FS. Lower the tilt, and you can actually paint mountainous terrain (with proper shadowing), rivers and shorelines. Run the tilt upwards, and you get a radar picture thats actually representative of what you see out the windscreen. You won't see thunderstorms on the radar if there aren't any out there.Not to mention the fully simulated EGPWS with TAD display, PEAKS format and worldwide terrain database. You should probably learn a bit more about the LSH product before bashing it so readily. The Maddog has a lot of features I've not seen anywhere else, like working circuit breakers, a huge number of unique failures, and (coming soon) the ability to defer equipment prior to departure. Regards,Nick

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>No, we did not simulate this system and for good reason:>>FSX's famous and highly unrealistic "wind shifts" do not in>any way represent what happens with real world windshear and>there is no accurate simulation of it available within the FSX>weather system. This would lead to quite frequent windshear>warnings which we determined would probably confuse the great>majority of our customers into thinking that either 1. they>did something to cause it, or 2. they should do something when>the warning happens, which isn't true because of how>unrealistic the FSX weather is.>>So just to put to rest any conspiracy theories - yes, we could>very easily do this, but as with the wx radar requests, we'd>be simulating something that can't actually be simulated>accurately due to how FS itself works, and that's not>something we're going to do.Ryan, don't you think that the purchasers of the MD-11 would also be owners of one of the excellent weather add-on products the gets around FSX and FS9 poor weather simulation? These add-on's can pretty well depict current, actual weather pattern and flight anomalies like wind shears, wake turbulence, etc. Do any of your beta testers not have a weather add-on? As you state, it's easy for you to do, but you assume that most of your users will be using default FS weather. I hope you have another look at both WX Radar and wind shear systems. You seem to do a pretty good job of simulating non existent air molecules flowing over simulated wings to create simulated lift in this simulator! Surly you could do the same with rain drop's.Steve Park

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>These add-on's can pretty well depict current, actual weather>pattern and flight anomalies like wind shears, wake>turbulence, etc. Frankly I don't believe it for a second. As of know there isn't even a single weather add-on (yes, I do have them) that is capable of overcoming FSX's basic problems with atmospherics like discontinuities in winds, pressure, visibility, etc. Of all the components in FSX weather is probably in its earliest infancy. Whatever someone claims to deliver in the future .. we have to wait and see but I would not hold my breath.Michael J.http://img142.imageshack.us/img142/9320/apollo17vf7.jpg

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Maybe someone would like to quell this:Did the weather system in FSX actually get built from scratch, or is it a modified FS9 weather engine, with a few new extras?I keep reading about how bad the FSX weather system is - it reads like it is totally new and totally broken compared with FS9.There are a lot of neat little utils for FS9 that simulate things the default weather system can't do, and it works well.IMHO, just because FS weather is not realistic, does not mean that features such as weather RADAR and winshear couldn't be implemented.FS can quite easily be set up to simulate wind shear (I suggest you study what it actually is), and there are a couple of add-ons out there that already have wind-shear warnings (DF 727 and LSH MD2006), and model it well. I don't get wind-shear warnings in the cruise, either.With default weather I've encountered wind-shear, and with the likes of AS this seems to be improved.I think it's a shame PMDG didn't do this TBH. "It's not realistic" doesn't cut it. I could pull FS apart quite easily on that score. ;) The same goes for weather RADAR - so long as the equipment can be operated something like realistic, I couldn't care frankly. All it has to do is draw something resembling what's out the virtual window. Reality-XP did a fantastic job in this regard, and LSH did well, too. The lack of weather RADAR is less realistic than one that tries. :)Best regards,Robin.

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>Where do you get the "Mad Dog" from? I'd like to check it>out, have a look at it.Have a look here: www.flythemaddog.com Jan-Paul

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Gents-I've had the good/bad fortune of experiencing windshear in an airplane (twice), in the full motion sim (dozens and dozens of times //sigh//) and of course I've tried to replicate it in FS using a myriad of weather products.To add my $0.03 (comes out to

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What about just a weather radar? It's quite unrealistic to see the ND plain and black.Ice

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>Where do you get the "Mad Dog" from? I'd like to check it>out, have a look at it.IMHO the Coolsky "MadDog" is much better. Plus they have the classic analog version as well as the modern FMC version.Excellent systems, modeling and FPS!You can find it here...http://www.coolsky.no/

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>What about just a weather radar? It's quite unrealistic to>see the ND plain and black.If there is no precipitation that's what you are going to see - plain and black, so hardly unrealistic :-eekOn the subject of weather radar - I suggest you search for threads that have "weather radar" in their titles - the subject has been beaten to death.Michael J.http://img142.imageshack.us/img142/9320/apollo17vf7.jpg

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>If there is no precipitation that's what you are going to see>- plain and black, so hardly unrealistic :-eek>>Michael J.>http://img142.imageshack.us/img142/9320/apollo17vf7.jpgAnd what you see on your ND when there IS precipitation is much more realistic I guess...oh that right you see nothing too! The LSH and PSS radar simulations do a pretty good job, but if you like looking at nothing, then stick with the PMDG modeled WX radar. It's MEL'd.Steve

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The way it was explained to me (regarding winds in FSX) is that you tell the sim you want 330/45 kts and the sim outputs 260/22 kts.Things like that.The band-aids that HiFi and Pete Dowson have done are wonderful but the bottom line is paragraph #1, above, which is the way it was explained to me once.RhettFS box: E8500 (@ 3.80 ghz), AC Freezer 7 Pro, ASUS P5E3 Premium, BFG 8800GTX 756 (nVidia 169 WHQL), 4gb DDR3 1600 Patriot Cas7 7-7-7-20 (2T), PC Power 750, WD 150gb 10000rpm Raptor, Seagate 500gb, Silverstone TJ09 case, Vista Ultimate 64ASX Client: AMD 3700+ (@ 2.6 ghz), 7800GT

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>IMHO the Coolsky "MadDog" is much better. Plus they have the>classic analog version as well as the modern FMC version.>>Excellent systems, modeling and FPS!>>You can find it here...>http://www.coolsky.no/Yeah right... I'll just pretend I didn't read this...

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