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GSalden

MD-11 flying faster than set ?

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Hi all,When flying slower at lower altitudes the speed seems correct.However at higher altitues the speed that is set gets different form the speed the aircraft is flying.Am I doing something wrong here ?See the attached screenshot. Gerard

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Gerard,Make sure you have Indicated Air Speed set in FS settingsHope it helps,

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Hi all,When flying slower at lower altitudes the speed seems correct.However at higher altitues the speed that is set gets different form the speed the aircraft is flying.Am I doing something wrong here ?See the attached screenshot. Gerard
I do not think that the problem related to indicated air speed.There are several other problems in your picutre:1. engines are off as indicated ?! (No N1, EGT, N2)2. Your current speed in the overspeed range ????Something definitely wrong here.Matyas Majzik

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Your panel is a mess. You read the manuals at all?? No FMS speed or NAV modes engaged. Landing altitude not set (FMS not programmed). TCAS off, CLB thrust at cruise. 29.83 baro at FL330? What are you doing???

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Your panel is a mess. You read the manuals at all?? No FMS speed or NAV modes engaged. Landing altitude not set (FMS not programmed). TCAS off, CLB thrust at cruise. 29.83 baro at FL330? What are you doing???
Because I am beta testing groundtextured at lots of places I am just flying and not making paricular fights.Therefor I do not use the fmc, just the autopilot.When the speedindicator is showing knots it is all correct.Only with Mach they are different.I thought it had to be the same even when not using the fmc.

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Without digging too deep into your observation, I strongly suspect that what you are seeing is the MD11's alpha protection (stall protection) system trying to save you. The MD11's wing is basically a DC10-10 wing with minor modifications. In other words, the wing is on the smallish size for the weight of the aircraft. As a result the speeds are higher to generate the needed lift. Clean speed, with flaps and slats fully retracted can be over 244 KIAS at some weights. You can use 200KIAS as a safe speed with slats extended, 0 flaps.The stall protection system will first use autothrottles to try to maintain your minimum speed, then extend the slats to try to save you, before stick shaker and pusher activation. Try sticking slats out and see if the autothrottles hold commanded speed better. In the real world autothrottles are nice, but not perfect. I see them get 10 knots fast, or slow. Consider the effect of winds. If you have a 80 knot tail wind and change heading into the wind, the total change on the jet is 160 KIAS. At FL 350 the effect of the wind shift is 272 knots ground speed. Sometimes we forget what we are asking autothrottles to accomplish on a half million pounds of airplane with enormous engines that require time to react.

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Haha very funny.
Yes indeed HAHAHAHA, at least some of us know a joke when we see one!
Am I doing something wrong here ?Gerard
HAHA yes, veeeery funny.....Carl

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The aircraft is flying to fast for stalling as I can see when using Shift + Z.This sounds very plausable : thanks for th explanation.In the real world autothrottles are nice, but not perfect. I see them get 10 knots fast, or slow. Consider the effect of winds. If you have a 80 knot tail wind and change heading into the wind, the total change on the jet is 160 KIAS. At FL 350 the effect of the wind shift is 272 knots ground speed. Sometimes we forget what we are asking autothrottles to accomplish on a half million pounds of airplane with enormous engines that require time to reactQUOTE (VIPERGTSR01 @ Apr 26 2009, 09:45 AM) Haha very funny.Yes indeed HAHAHAHA, at least some of us know a joke when we see one!QUOTE (GSalden @ Apr 26 2009, 06:51 AM) Am I doing something wrong here ?GerardHAHA yes, veeeery funny.....CarlI suggest these are just small children who do not even had a clue why exactly the issue appeared....Gerard

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Because I am beta testing groundtextured at lots of places I am just flying and not making paricular fights.
Then pick another much simpler aircraft for your testing ... as others suggested your panel is a total mess and your engines seem to be completely out. If you don't want to learn how to fly MD-11 properly (yes, you can fly it without FMC) - give it up, this is not a Micky Mouse simulation that you can pick up in 5 minutes. :(

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The aircraft is flying to fast for stalling as I can see when using Shift + Z.This sounds very plausable : thanks for th explanation.In the real world autothrottles are nice, but not perfect. I see them get 10 knots fast, or slow. Consider the effect of winds. If you have a 80 knot tail wind and change heading into the wind, the total change on the jet is 160 KIAS. At FL 350 the effect of the wind shift is 272 knots ground speed. Sometimes we forget what we are asking autothrottles to accomplish on a half million pounds of airplane with enormous engines that require time to reactQUOTE (VIPERGTSR01 @ Apr 26 2009, 09:45 AM) Haha very funny.Yes indeed HAHAHAHA, at least some of us know a joke when we see one!QUOTE (GSalden @ Apr 26 2009, 06:51 AM) Am I doing something wrong here ?GerardHAHA yes, veeeery funny.....CarlI suggest these are just small children who do not even had a clue why exactly the issue appeared....Gerard
As a student pilot in the real world I would like to tell you that you can stall at any speed. It all depends on angle of attack so to speak.

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I suggest these are just small children who do not even had a clue why exactly the issue appeared....Gerard
Hey the aircraft is setup so wrong, so far into red tape I thought this was a joke, I wouldn't expect the aircrafts autopilot to do what it's told while in the red. Maybe try it in a correctly setup aircraft and see if it still does it.

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Something is totally off.No engine indication but Fuel Flow? Did you modify the .air file of the aircraft or do you use some non-PMDG external tool to change the payload and fuel?As someone has already mentioned your angle of attack is too high. Notice the magenta indicators at ca. 2 deg up. Your nose should not go any higher than that.How long have you been in the cruise in this screenshot? Your CoG looks a bit far to the aft for me.Maybe as a result of that elevator trim is a bit off, too. I usually get something like 0.2 ANU when I am in cruise. But this is just guessing from my side.If you give us your payload and fuel info someone could try to recreate your problem.Regards

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Hi Folks, it's a joke ! Don't you see it !It is a late 1. of April joke !Tka a look at the picture, VC cockpit with missing details, odd angle to the panel. Who would care to first use something like active camera in order to provide us with a picture to show this kind of problem.It would be much better and easier to capture the picture in 2d panel. No N1, wrong QNH and so on.......No one would have called other people childish if not for the purpose of exalate the whole joke when the issue is that way off. Who buy a PMDG MD11 and put such a topic to the forum . common folks - it's a joke !Carl

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For me I guess that you have to turn on the Anti Ice, the TAT is -32Regards.
Hey Ibrahim, you may want to read up on the use of Anti Ice, a TAT of -32 does not mean you need to use Anti Ice. Anyway from the screenshots that's the least of his worries.CheersRob

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At FL330 this is a normal temperature and anti ice is not required unless there are signs of icing or moisture.

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Because I am beta testing groundtextured at lots of places I am just flying and not making paricular fights.Therefor I do not use the fmc, just the autopilot.When the speedindicator is showing knots it is all correct.Only with Mach they are different.I thought it had to be the same even when not using the fmc.
Gerard,Just a hint:If you want to beta test something, test it within the FS environment, using a default FS airplane that suites your speed.In the same way I exclude all add-ons when charlie (=customer) testing the MD11.Hope it helps.Harry

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No.. more than likely this a pirated fs9 version of the MD11.Peter Osborn

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Gerard,Quite frankly this is not the aircraft for you if you aren't going to read the tutorial flight at the very least and attempt to learn how to fly it correctly. Real aircraft do not function like the Microsoft default aircraft and simpler addons you're probably used to. You need to configure the FMS, pay attention to your weights and maximum altitudes etc. I really have no idea how your engines are showing 0% N1 in this screen shot tho, can you explain that please?

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No.. more than likely this a pirated fs9 version of the MD11.Peter Osborn
Incredible , you are allmighty ! :( At PMDG they can see that I have an official version.I need good input and not those hollow phrases.If you want to beta test something, test it within the FS environment, using a default FS airplane that suites your speed.Normally that is correct, but at the same time I am modifying land/lakes /sea/autogen and building custom scenery for certain area.Because I want to be able to fly very detailed scenery with the MD-11 I am flying around with the MD-11.if I can fly there witth the MD-11 I can fly eveywhereToday I was flying over Tunesia and yes I did start the aircraft as it should.However I did not intend to fly with the FMS for those short flights, so I use the autopilot.Immediately when returning to the airport I remarked the following;When setting the speed below 220 knots the aircraft remained at 220 knots. The airaft was filled up with fuel about 1/3.If , in a real situation, the FMS in a MD-11 would not function properly it should be possible to use the autopilot I thougt.Here a screenshot.Now I need someone serious who can explain this. ( When the scenery is ready I will upload it and then I will read the whole aircraft manual , ok ? )

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When setting the speed below 220 knots the aircraft remained at 220 knots. The airaft was filled up with fuel about 1/3.If , in a real situation, the FMS in a MD-11 would not function properly it should be possible to use the autopilot I thougt.
This is just because the speed you selected is below the minimum speed for your flap/slat setting, MD-11 will never allow you to decelerate to a speed that is under manouvering speed for the selected flap setting. Increase your flap and you will reach 200kts.... I suggest you to read the manuals if you want to fly this bird, even if you just want to fly around....RegardsStefano

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As someone else already said: I think the stall protection system is saving you. You want to fly ay 200 kts but as you can see on the PFD that speed is in the amber (yellow) zone! it is too slow for your current configuration. Your speed has to stay above the amber zone and since you don't do that yourself, the plane does it for you, keeping you at 228. I guess somehow somewhere your systems aren't setup right. Anyway, if you want to continue flying without this apparent difference in speed, set the speed to something like 240. Or add slats or flaps 15: that will probably lower the amber line, bringing 200 kts in the safe zone.EDIT:Darn, geckuz beat me to it... :(

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