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Speedbyrd

Steep descent angle....

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My DC-10's come in at very steep angle on final approach, especially if using ILS. My other aircraft and real life aircraft come in at a slight 'nose-up' attitude, but these come in almost at a nose dive at 145 kts, then I have to pull up the nose abruptly to get an 'all wheels' level touchdown. It seems the nose wants to come down when the rest of the plane doesn't. Any idea how to correct that? Otherwise, it flies like a dream. Thanks

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Might be helpful if you provided the name of the DC-10 file which displays this problem and where you got it.

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oh sorry, it's SGA payware. They issued a so-called 'upgrade' to the aircraft.cfg and *.air file but I think I liked the original one better.

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>oh sorry, it's SGA payware. They issued a so-called>'upgrade' to the aircraft.cfg and *.air file but I think I>liked the original one better.SGA payware???!!!SGA (also FFX) made freeware and the group no longer exists ... broke up, like, 2-3 years ago. their models (DC10, DC9/MD80, 737 (what else have i missed?)) are available in the avsim library.--

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Make sure your gross landing weight is not over the limit for your approach speed. You also need to make sure your CG is not outside of limits when landing.As the aircraft slows to approach speed the elevator has reduced authority and may not generate enough downward force to lift the nose into the proper attitude.If because of overweight conditions the nose has too be raised too high to maintain speed and rate of descent, then you could also be entering a stall if the angle of attack is high enough.Use your calculated landing gross weight to adjust your speed for the flaps you have selected.

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>>oh sorry, it's SGA payware. They issued a so-called>>'upgrade' to the aircraft.cfg and *.air file but I think I>>liked the original one better.>>SGA payware???!!!>>SGA (also FFX) made freeware and the group no longer exists>... broke up, like, 2-3 years ago. their models (DC10,>DC9/MD80, 737 (what else have i missed?)) are available in the>avsim library.>>>--whatever. I thought I had paid for these. I've had them for some time but just recently installed the 'upgrade' to the fde.

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>Make sure your gross landing weight is not over the limit for>your approach speed. You also need to make sure your CG is not>outside of limits when landing.now we're getting into the area of aircraft design which I know little about. How do I know what the GLW is or should be? and the c of g? how do I know what the settings for this are?>>As the aircraft slows to approach speed the elevator has>reduced authority and may not generate enough downward force>to lift the nose into the proper attitude.>>If because of overweight conditions the nose has too be raised>too high to maintain speed and rate of descent, then you could>also be entering a stall if the angle of attack is high>enough.that happens. If I pull the nose up so that the plane is level, I lose speed very rapidly. >>Use your calculated landing gross weight to adjust your speed>for the flaps you have selected.ok, help?GLW for this aircraft is 575,0000 lbs but I'm no where near that as I only carry like an extra hour of fuel. I usually use flaps 30-35 for a normal landing. The condition seems to worsen as I add flaps.

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Slow down*. If the nose is too low on final approach then you're going too fast.Slow down and you will have to raise the nose to maintain lift and flightpath angle (hopefully 3 degrees in this case).Hope this helps,Ian*Assuming you're not too heavy, the flaps are set correctly and the aircraft is within the correct CofG limits.

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well my approach speed is 145 kts which I think is about right for the D-10. We're coming in with about an hour's worth of fuel, I don't think we're heavy; flaps are at 30. The CofG is where I'm stuck. My other aircraft come in almost perfectly level, so the c of g may be the issue here but that's not something I know how to tamper with.

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Why not experiment? Look under the Aircraft menu and find the Fuel and Payload page. Manually move some weight from the forward part of the aircraft to the rear. Some passengers might complain about having to sit on someone's lap but others will be delighted. Try it and see if you can strike an acceptable balance.R-

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oh, so I could probably recruit new members to the 'mile high' club and this would be a perfect example of multitasking! LOL

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increasing flaps will bring the nose down. if you're not heavy, try less flapscheers

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You're approach speed is too fast.If you are 'guestimating' that 145kts the right speed for your approach are you taking into account the gross landing weight of the aircraft (fuel+passengers+baggage+zfw)?DC-10s and L1011's have a higher AoA at approach speeds than most aircraft so if your speeds are right you will be approaching in a decidely nose up attitude.Airspeeds for a given aircraft for a given weight (V1, Vr V2, Vref, etc) are absolute numbers. If you are incorrect in your calculations then your aircraft will not fly the way you want it to or expect it to. Also, your approach speeds may vary but you need to ensure that you are coming across the fence at Vref, or: 1. you will float down the runway like a baloon when you flare, or, 2. you will have to dive the aircraft into the runway to get it to settle. Both are bad. Also, you should never land an airliner in an 'all wheels touchdown'. The nosegear is not designed to take the stress of the full gross weight of the aircraft upon landing and will collapse which is why you 'flare' to ensure your main gear absorbs the full weight and then gently put the nose down.If you do not have speed charts for your DC10 then you will need to experiement. Try the same approach between 130 - 135kts and see what happens. Additionally, I don't know how good the flight model is for your SWA aircraft so you may have to fudge the numbers. In either case, your current 145kt approach guess is wrong for your given configuration.Basic airmanship: a good approach makes for a good landing.HTH,Mike T.

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>You're approach speed is too fast.>>If you are 'guestimating' that 145kts the right speed for your>approach are you taking into account the gross landing weight>of the aircraft (fuel+passengers+baggage+zfw)?>>DC-10s and L1011's have a higher AoA at approach speeds than>most aircraft so if your speeds are right you will be>approaching in a decidely nose up attitude.>>Airspeeds for a given aircraft for a given weight (V1, Vr V2,>Vref, etc) are absolute numbers. If you are incorrect in your>calculations then your aircraft will not fly the way you want>it to or expect it to. Also, your approach speeds may vary but>you need to ensure that you are coming across the fence at>Vref, or: 1. you will float down the runway like a baloon when>you flare, or, 2. you will have to dive the aircraft into the>runway to get it to settle. Both are bad. >>Also, you should never land an airliner in an 'all wheels>touchdown'. The nosegear is not designed to take the stress>of the full gross weight of the aircraft upon landing and will>collapse which is why you 'flare' to ensure your main gear>absorbs the full weight and then gently put the nose down.>>If you do not have spped charts then you will need to>experiement. Try the same approach between 130 - 135kts and>see what happens. >>Basic airmanship: a good approach makes for a good landing.>>HTH,>>Mike T. I misspoke regarding the 'all wheels' touchdown. What I was trying to say was regarding getting the aircraft to come in level or at a slight 'nose up' with main gear touching first. I'll work on the approach speeds. I got my stats off the Boeing and McDonnel-Douglas; Airbus performance webpages for their various aircraft. I'm also finding that 35 flaps may play into this as I ususally come in fairly light. I normally don't carry a lot of payload and load enough fuel for the flightplan + 1 hr.

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Speed:Please do NOT take the INCORRECT post given about using less flaps. Your problem is not with your flaps its with your speed, it makes no difference whether your light or not. You reduce your speed, NOT your flaps!!! You can be in an empty 737 with just IFR reserves and you will still use flaps 30 (or 40 if you really want to get off the runway fast).Find out what the proper Vref is for your given configuration and then match that with your flaps chart. You ALWAYS want to approach at the slowest available speed for your weight and taking into account the winds (Vref+5 as the speed at which you come over the fence.) Remember, flaps are there to: 1. allow you to increase your rate of descent without increasing airspeed and 2. Increase lift as you decrease airspeed. 3. Decreases the stall speed for a given landing configuration. Decreasing the use of flaps increases the airspeed required for a given weight, decreases the rate at which you can descend because you will increase your airspeed AND increases your stall speed. The less flaps the faster you must go, the faster you must go the steeper the pitch angle required which increases airspeed...you then find yourself back exactly where you are now.HTH,Mike T.

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Flaps add both lift and drag. The effective angle of the wing chord when you add flaps increases upward. This allows the fuselage longitudinal axis to remain fairly level compared to the up angle required without flaps to get the same amount of lift as with no flaps at about the same speed. It is therefore normal once stable to have a lower nose-up attitude with flaps than without at normal flap range speeds.In normal flap design most of the settings except the last one or two add both lift and drag, the last few being mostly drag only.The reference stall speeds at max gross weight are in the aircraft.cfg for each flap setting. Add 30% to these for a V-ref at each setting. Only charts would give you the actual speed based on current weight. The entries only control the stepping of the flaps control but the stall speeds do not have any effect on the aerodynamics.I see in Werner Schott's DC-10 checklist a flat value of 145 is given and that you are using that.One worthy note is that if trying to use an FS8 aircraft in FS9, they tend to be nose heavy due to different dynamics in the FS aerodynamics engine. If this is an FS8 aircraft then there needs to be an edit nade to the .air file with the aired utility. I do not recall the specifics but perhaps you can search the forums. The fix is posted somewhere.Try putting in the FS fuel/load control menu the gas you've got when your landing starts and see where the CG falls on the diagram.The only suggestion I have is to try a few landings carrying some extra speed.If you are using autopilot for landing it is possible the elevator trim as used for A/P control is out of range since you state you can manually pull the nose up. This is just something to check.You do not say what model you are using. You might find another one and see if substituting its .air file helps. Make sure it is an FS9 one.All I can think of at this moment.

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I'm good with all that. I'm using the SGA model (both the older one and so-called 'upgrade'). I'm thinking of trying the dynamics for my MD-11 as the aircraft are fairly similar except for weight. My SMS MD-11 seems to have near perfect flight dynamics so I might make some substitutions of the 'lights' and 'contact point', fix the weight and see if I can duplicate it in my D-10

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