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Hotfix 4 and high speeds on final approach

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I have installed Hotfix 4, and I believe I have read somewhere that this will result in the NGX being more slippery/hard to slow down than before. I'm assuming that was done for the sake of realism, but I have noticed on two flights recently that I am having a very hard time keeping the speed in check during final approach, so much so that I am busting flaps speed limitations.I was on approach to KPHL runway 9, and had slowed to 170kts & flaps 5 at the FAF. I started the descent on the glideslope and at the point where I usually drop the gear/flaps 15 at 2000ft AGL, the speed had accelerated to about 180-190kts, and steadily increasing by the second. Hoping to kill off speed, I dropped the gear, but that did little to bleed off speed. I was mindful not to extend more flaps for the sake of adding drag, as they are not really designed to be used as a drag device unless the appropriate speed bug is matched on the PFD. Eventually, I just took manual control as I usually do, but sooner than usual (at 1500 ft, I usually wait until after I'm established with final flaps and at about 1000ft agl). I will have to practice some more landings to see if this is glitch on my end, but I doubt it. I have months of experience with the NGX and the previous hotfixes, and I only noticed this behavior since installing HF4. I can't help but wonder if PMDG, while fixing the nose pitch issue on final approach, somehow broke the aerodynamic model in a way that makes the NGX a little too slippery. See screenshot below.

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Hi, A/T Manual override in Options?Since HF4 the behaviour with this setting has changed. Look at N1. It´s not at idle and speed is high.If you set it to never, the ac will fly like you were used to, At least in my case.It´s not realistc, though. Best. Miquel Egea.

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Guest tonyf38

Try this, flap10, 170 kts..Once glideslope comes alive(not capture) gear down flaps15.. Gear and flap15 should be selected before glideslope capture not while descending..

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Flaps 10 sounds like a good idea, I've been using flap 5 up to capture because I had no idea if flaps 10 was even used IRL.

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Try this, flap10, 170 kts..Once glideslope comes alive(not capture) gear down flaps15.. Gear and flap15 should be selected before glideslope capture not while descending..
Not what all airlines do in real life at all....many won't have gear down till 5/4 dme as it saves a load of fuel. Will be flaps 10 170kts knts till 5dme, then gear down and speed back to vref commanding to landing flap as speed reduces, should be at landing flap and speed 1000/500ft agl.I think in the case of the user above is problem is that of what the other user posted, in that the idle isn't becoming the proper idle. The PMDG since HF4 as some issues in how it manages idle. As the eec command different n1 values the throttles aren't always changing to the lowest of this value sometimes. Either disable this, or at regular periods keep repulling throttles back to idle or pressing f1 to check that the lowest EEC commanded n1 is actually being selected,

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RW, if you're on the G/S, sometimes F5 will keep you on speed. Sometimes the plane will accelerate; it depends on the wind and weight. If I was at F5 maneuvering speed while joining the G/S and the plane starts to accelerate, I go to F10 if I'm a ways out on final. If I'm closer to the FAF, I'll just go gear down/F15. Most pilots don't use F10, but it fills that niche nicely


Matt Cee

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Guest tonyf38

I don't have Hotfix 4, does it make it change the flight dynamics that much?

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I'm using Hotfix 4 and never have any trouble slowing down. This ain't real world guys as many are fond of saying, It's a SIM! Just do whatever it takes to slow down, even if it's not RW! There is obviously some minor fine tuning that needs done for SP1 but it still does not prevent me from getting it in there at any speed I want it to. When I am on final approach and descending I am at Flaps 15 and 175 knots until just before the outter marker. (We do not have co-pilots and have to do everything ourselves, so you have to plan ahead, and do things a little earlier than RW). By time I hit the outter Marker I have VREF Speed set, Gear Down and the speed is slowly bleeding off. Around 160 knots I select Flaps 25 and then finally Flaps 30 or 40 depending on runway length and weight. Because they used the Unreliable Speed tables and the bird is 10 knots hot I use the following forumula. VREF + Half the Wind + All of the Gust and whatever the total is -10. So therefore I am not using the +5 and actually taking -5 knots off. Works just fine for me and I can do a nice graceful flare just like you see in real world videos, rather than coming in hot and near flat or floating. One important thing to note: You should not be using FSUIIPC Calibration Tab for any reason! This was totally screwing things up with auto-throttle when I tried to use it for getting thrust reversers to work on my X52 Pro. The only thing FSUIPC should be used for is assigning buttons, autosave, or wind smoothing. No Calibration or Axis assignments. The NGX uses Simconnect and obviously the two do not get along. Calibrate your controllers using FSX or Game Controllers in Control Panel before leaving the gate every flight. If you have calibrated anything in the past with FSUIPC calibration go back in there on Page 1 and 3 and hit the reload all settings button. Finally for those that do not know, the Thrust Options moved in Hotfix 4 and are in a different location. SETUP - OPTIONS - SIMULATION - PAGE 2. They also do not work like before where you selected one and they changed to Green for Active like the other options do. You have to hit the left FMC key next to the Text to cycle through the availble options. It works this way for both Show Thrust Lever Position and At Throttle Manual Overide.

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Just any update on above. With Flaps 30 -10 is too slow, so using VREF + Half the Winds + All the Gust with no +5.

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Because they used the Unreliable Speed tables and the bird is 10 knots hot .
Actually no, thats not true. The VREF speeds are accurate. What wasn't, was the pitch on approach. However... After hotfix 4, the pitch is now more or less accurate. The correct VREF for the SFP isn't implemented though, so you will have to knock a few knots off to simulate that.

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Actually no, thats not true. The VREF speeds are accurate. What wasn't, was the pitch on approach. However... After hotfix 4, the pitch is now more or less accurate. The correct VREF for the SFP isn't implemented though, so you will have to knock a few knots off to simulate that.
I agree with Martin, I believe the pitch issue has been addressed with HF4 and the user no longer has to compensate for the incorrect pitch attitude by adjusting VREF by subtracting 5 knots (except for the SFP of course). The possibility that HF4 is messing up idle thrust seems plausible, though I was sure I had my hardware throttles at the lowest setting possible even when it was overspeeding, I will have to do some more tests. But this I'm certain, I NEVER had the a/c overspeed the flaps on finals with all the previous hotfixes, and I'm hoping that PMDG is aware of this issue and corrects it for SP1. I am afraid that they took one step forward (fixing the pitch issue on finals) and two steps back with the idle thrust setting.

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Ok, I just completed two approach/landing scenarios without any major hoopla. I feel I should now retract my comments saying that there is a serious glitch in the flight model on finals, it just now appears that there is a much higher potential for the -800 to overspeed if the pilot is not properly prepared at glideslope capture. Namely, that means that once you are at flaps 5 maneuvering speed shortly before the FAF, it would be prudent to keep an eye on the speed before descent. I have heard that sometimes ATC (KPHL particularly) will ask the pilot to maintain 180kts to the OM, which in this case means about 6 nm and 1800ft from the runway threshold. But with 180kts in the 800, it is very very difficult to slow down while descending, hence the issue I was experiencing with busting flaps speeds. Now in hindsight, I will have to "tell" ATC I am unable to do 180kts and that it would be preferable to slow to 170kts BEFORE descent, not at the OM while I'm also descending. The moral of the story, more than ever, stay ahead of the aircraft! I am going to attribute my past overspeed conditions to a lack of understanding of the handling quirks of the -800, and that the reason I didn't see this behavior before is that PMDG only recently tweaked the flight model to make this behavior more noticeable with HF4. However, can a real world pilot with NG experience chime in, is this now more slippery perfomance with HF4 realistic?

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I tried the ngx after HF4 only few times, but experienced same issues related to the final approach.On glide slope path was nearly impossible to slow down, throttles are back, idle speed is "correct", lowering gears does not help too much, I landed 2 times in overspeed with flap 15, one time with brake failure.I was thinking that was my failure... but very strange that is very similar to this one.I'll try again to confirm but before HF4 was simpler to slow down.


Regards

Andrea Daviero

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Thanks for the supporting observation Andrea. I really don't know what to make of this behavior after HF4, on one hand I am guessing this is how the real bird performs, but another part is skeptical and believes it may very well be a glitch or incorrect flight model behavior. I've been well aware that the 800 is a beast to try to slow down, but I thought that was to be expected at the higher speeds and not after I have dropped flaps 5 and have slowed below 180kts. Anyhow, I hope this post has gotten PMDG's attention and we can get some clarification from them or any real world crew.

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