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teopereira

Getting "too high" for the final approach

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For me the approach all goes well untill intercepting the GS. I normally pick it up from below but the ROD is minimal 1100 ft at 180 kt between 2000 and 3000ft (when airport is at sea level or adding the elev of the airport). 1100 ft or 1200 ft is way to steep which means I have to land manually all the time which is fine but shouldn't be mandatory. With all other PMDG aircraft (MD11, 747 and T7 no problem and all smooth... 

 

How to solve this ROD at short final with the NGX?

 

Regards,

John

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How to solve this ROD at short final with the NGX?

 

At idle throttle with the flaps and gear out, you should have absolutely no problem at all. In fact, in the landing config, the throttles are usually somewhere about 50% if I recall correctly.

 

Sounds like you're just not properly configured.


Kyle Rodgers

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Sounds like your airspeed is too high, at approach speeds you should be descending at about 800-850 fpm.  This plane is sweet to fly on final, at glideslope intercept I drop gear and flap schedule kinda depends on situation.


Dan Downs KCRP

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Thx for the answers.

 

I know from KLM and Transavia they go normally to flap 15 and gear down between 1800 and 2000ft. With the PMDG when you keep the speed even at flap 15 speed it runs away even when the wind is calm. Trottle is Always at 37% in AT and when disconnect it goes to 32%. Didn't use the override function for my throttle.

 

On the other hand, in TO and you set the AP on above 400ft it pitches even up to 10 anu and corrects itself. And trust me, I follow the needle and trim is set as told in the FMC. With tha as mentioned before, with all other PMDG addons, no problem.

 

I'm using ASN and FSUIPC (paid). Maybe there is something I missed?

 

Kind regards,

John

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Maybe there is something I missed?

 

Apart from poor technique, I don't see what else it could be, honestly. Calm wind isn't going to affect your airspeed (which leads me to my earlier assumption - technique). While, sure, it affects groundspeed, which then affects your descent angle, the wind shouldn't be too relevant to this issue.

 

Have you flown the tutorial flights?

 

Also, full names in the forum, please. I've been pretty lenient after the announcement that we're supposed to be removing posts and issuing warnings. That will be ending soon enough.


Kyle Rodgers

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I know this isn't popular, but if it quacks like a duck . . .

 

The RW configured N1 settings should be 57% at F30 and 62% at F40. Calm winds in a smooth morning, you can almost set that and leave the TLs alone until 30ft.

 

If you're on the GS and can't maintain target airspeed with those very closely, then there is a problem with the model.


Matt Cee

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@Kyle, please elaborate me. When you're on AP picking up the GS at 180 kt 2000ft, flap 5 and the speed runs away... How do you mean "poor technique"? I'm in this since FS4, multiple hours on the real (KLM) sim so if you don't know the answer don't answer it because you just insult people with it.

 

@Spin

When picking up the glide I'm gaining about 20kt... It's just a nose dive! Did in the real sim a hot and high approach and was stable at 1000ft, fun to do. Not sure if it's a model problem because I'm just one of a few who's having this problem I guess.

 

Regards,

John

Rossie (hope you're happy now Kyle)

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Matt C is an experienced 737 jock who is a regular contributor to the forum... I'd take his comments serious.

 

Gaining 20 kts on glideslope intercept, nose dive, all these point to a problem with your approach airspeed before intercept. You're too fast or you've too much tailwind. Slow her down to flaps 15 before glideslope intercept and drop the gear and rest of flaps at glideslope intercept and see how that works out for ya.


Dan Downs KCRP

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@Dan

I took his comment serious! Was glad with his reply.

I'm not landing with tailwind only when no other option is available. Even when speed for flap 15 my ROD is about 1200 ft when picking up the GS which is way too much. I've flown a zillions times with the 738 and when speedbrakes are used it's normally in the decent not on final. I need speedbrakes, gear down (too early) to adjust it.

 

Regards,

John ROSSIE   

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@Kyle, please elaborate me. When you're on AP picking up the GS at 180 kt 2000ft, flap 5 and the speed runs away... How do you mean "poor technique"? I'm in this since FS4, multiple hours on the real (KLM) sim so if you don't know the answer don't answer it because you just insult people with it.

 

@Spin

When picking up the glide I'm gaining about 20kt... It's just a nose dive! Did in the real sim a hot and high approach and was stable at 1000ft, fun to do. Not sure if it's a model problem because I'm just one of a few who's having this problem I guess.

 

Regards,

John

Rossie (hope you're happy now Kyle)[/quote

It can get away from you, but you need to keep configuring if you don't want to let the speed get away.

 

Sometimes the speed won't settle with F5 so you might need F10. Be proactive.


Matt Cee

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@Kyle, please elaborate me. When you're on AP picking up the GS at 180 kt 2000ft, flap 5 and the speed runs away... How do you mean "poor technique"? I'm in this since FS4, multiple hours on the real (KLM) sim so if you don't know the answer don't answer it because you just insult people with it.

 

John,

 

Firstly, the forum requirement is a forum requirement. We were told to be pretty blunt with it and I could've hit you with warning points and deleted your posts. Think about that for a minute before you get passive aggressive with future responses...

 

Secondly, I've been flying the NGX since the day after it released without the issue you've been experiencing. Additionally, I haven't seen many (if any) posts with similar issues to the ones you're having in the nearly 4 years since it released. So, despite your time back to FS4, and time in a KLM sim, it's still entirely possible that you're not flying the plane correctly. I'd been flying the Cessnas in the sim since FS5, but when I started flying in the real world I didn't take offense to my CFI correcting my technique. Unfortunately, since you're not being too specific (and you're referring to items that are at least partially irrelevant - the wind), I don't have much to go on other than my assumption that you're just not doing it correctly. If you were more specific about things, then I might be able to give a more specific answer. Videos and pictures are worth a thousand words.

 

Finally...

 

Remember that we're all posting here to help you. It might not feel very good to hear "you're not doing it right," but such is life. It's best to take the approach of "maybe I'm not doing it right" instead of reacting negatively to the idea. Heck, Dan told me I was wrong the other day and I just said "you know what - you're right!" Nobody is getting points here for being right or wrong, or for telling others that they're wrong. I only said your technique might not be right on the assumption that I'd be putting you on the course to finding out the right path.


Kyle Rodgers

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The thing that cornfuses me about this dilemma is the ROD..  1100-1200 doesn't sound

right if following the glide path. Should be more in the 700-800 fpm range.

 

And I don't know how many miles out you are to be picking up the glide path at 2000 ft,

but 180 knots at flaps 5 may be a tad on the hot side. And normally, the gear would be

coming down around that point, which should add more drag. Normally, the plane should

be slowing down if the AT is set to a lower speed, or if you are running manual throttle,

and aiming to slow down by pulling the throttle back. But I guess it depends on quite a

number of factors.. Myself, when on a normal approach, I tend to put the gear down about

one dot or so above the glide path. On a longer approach, maybe about the time I catch

the glide path. So I'm already getting the gear drag, slowing to around 150-160 knots,

and about to the flaps 15 stage.. But.. I may be doing things a tad different than the

manual. Some seem to drop the gear later than I often do. But I guess I'm from the old

school of dropping gear about one dot above glide slope, and old habits die hard..

 

But in general, I don't see the problems you have slowing down too often. Although I

would be telling a fib if I said I never see it.. I have a few times, but usually with the 800..

That's another thing.. I fly the 700 much more, and it's not quite as slippery as the 800 is.

 

But again.. I wonder how in the heck you can be on the glide path and be descending at

1100-1200 fpm.. That just sounds irregular to me for most normal ILS approaches.

I never get a "diving" capture of the glide slope, and usually end up about 700-800 fps

once I capture..

 

I try to fly the thing as accurate as possible, but I do also fly by sense of smell..

IE: if things looks flaky, I'll modify to adapt to the flakiness.. IE: if I'm fast and have a

hard time slowing down, I'll raise the brakes for a bit, and once slow enough, I'll hang

the gear, more flaps, or whatever it takes to slow the bad boy down.

To me, 180 knots and flaps 5 at a 2000 ft glide slope capture is a tad on the hot side.

I can usually make it work, but I tend to be a tad slower at that point, and will be dropping

the gear by the time I capture the glide slope, being a 2000 ft capture generally will

not be that many miles out, and I'd rather be stable early, than late.

 

An example of a flight I did today from Orlando to Montego Bay.. It's a visual approach,

but at the point I drop the gear and start my descent down from 2000, I'm already down

to the 150 or so knot range. With a Vref+5 at 134 knots for the final speed in.

I was about 200 at the point I start the turn onto the runway heading, and had no trouble

slowing down before descending from 2000.

If anything, I started getting a tad on the low and slow side before I made it to the runway..

I had to slow the ROD and goose the throttle a bit to cure the all red VASI I was seeing..

It's not showing on the ND, but the wind was kinda scruffy, and back and forth on the speed..

 

 

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The thing that cornfuses me about this dilemma is the ROD..  1100-1200 doesn't sound

right if following the glide path. Should be more in the 700-800 fpm range.

 

And I don't know how many miles out you are to be picking up the glide path at 2000 ft,

but 180 knots at flaps 5 may be a tad on the hot side. And normally, the gear would be

coming down around that point, which should add more drag. Normally, the plane should

be slowing down if the AT is set to a lower speed, or if you are running manual throttle,

and aiming to slow down by pulling the throttle back. But I guess it depends on quite a

number of factors.. Myself, when on a normal approach, I tend to put the gear down about

one dot or so above the glide path. On a longer approach, maybe about the time I catch

the glide path. So I'm already getting the gear drag, slowing to around 150-160 knots,

and about to the flaps 15 stage.. But.. I may be doing things a tad different than the

manual. Some seem to drop the gear later than I often do. But I guess I'm from the old

school of dropping gear about one dot above glide slope, and old habits die hard..

 

But in general, I don't see the problems you have slowing down too often. Although I

would be telling a fib if I said I never see it.. I have a few times, but usually with the 800..

That's another thing.. I fly the 700 much more, and it's not quite as slippery as the 800 is.

 

But again.. I wonder how in the heck you can be on the glide path and be descending at

1100-1200 fpm.. That just sounds irregular to me for most normal ILS approaches.

I never get a "diving" capture of the glide slope, and usually end up about 700-800 fps

once I capture..

 

I try to fly the thing as accurate as possible, but I do also fly by sense of smell..

IE: if things looks flaky, I'll modify to adapt to the flakiness.. IE: if I'm fast and have a

hard time slowing down, I'll raise the brakes for a bit, and once slow enough, I'll hang

the gear, more flaps, or whatever it takes to slow the bad boy down.

To me, 180 knots and flaps 5 at a 2000 ft glide slope capture is a tad on the hot side.

I can usually make it work, but I tend to be a tad slower at that point, and will be dropping

the gear by the time I capture the glide slope, being a 2000 ft capture generally will

not be that many miles out, and I'd rather be stable early, than late.

 

An example of a flight I did today from Orlando to Montego Bay.. It's a visual approach,

but at the point I drop the gear and start my descent down from 2000, I'm already down

to the 150 or so knot range. With a Vref+5 at 134 knots for the final speed in.

I was about 200 at the point I start the turn onto the runway heading, and had no trouble

slowing down before descending from 2000.

If anything, I started getting a tad on the low and slow side before I made it to the runway..

I had to slow the ROD and goose the throttle a bit to cure the all red VASI I was seeing..

It's not showing on the ND, but the wind was kinda scruffy, and back and forth on the speed..

 

 

Just watched your video.

 

You got up to -1150 v/s, but you were ducking under the 3.0deg. That was a momentary excursion, not a stabilized ROD. Not really an issue. If you had the LOC/GS up, if they have one, you'd have additional guidance.

 

More important to me: You should have had selected a F40 Vref of 134 and then you would have had the speed tape guides for the config. You were 24 knots slow when you put out your flaps. That's a bust. ;)


Matt Cee

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Yep, I ducked down pretty quick at first cuz I seemed a tad high visually. There was no ILS..

Totally a visual approach, with FSX ATC clearing me to the runway after reporting runway in

sight. There may be an ILS there now, or they use an RNAV approach, which I did show in the

FMC as an option.

But once I started to get a bead on the runway using the HGS, the ROD was fairly normal

around 700-800 fps I think as it would be following a ILS glide path.

 

About the flaps, I set F30 Vref for 129+5=134, and did have the speed tapes when I originally

flew it. All my videos are FSrecorder replays, and being I had landed, the FMC is cleared out,

and also many modes and the speed settings don't record as flown. I had started to drop

the flaps at around 190-180 or so, which is a tad later than I often do, but didn't think that was

bad news at that speed. Most times, I'm at about flaps 5 by 190 or so.. In the videos, I have

to manually set the speeds to appx match what I remember from the flight. So often they don't

exactly match..  :(

 

For some reason, I was thinking you could fly 180-190 knots with the flaps up with no real

issues except maybe a tad higher AOA than normal. I guess I'm wrong on that, and better

hang them out a bit earlier on all flights. I didn't think it was a real problem being as I don't

seem anywhere close to a stall. Maybe I better review the flaps sked in the FCOM...  lol..

 

Another thing about the FSrecorder replays and renders is the weather often slightly changes

on me from the time I flew it, until the time I render the video, even if I disable WX updates.

So sometimes I'll see speeds, flap retractions, that seem a tad off from when flown.

I wish I could record using FRAPS, but it bogs my mediocre machine down so bad that the

frame rate resembles a slide show. So I use FSrecorder being it gives a much better frame rate,

but doesn't properly record all modes and such.

An added pain is I have to record the audio track separate from another replay, and then mix

with the video when I edit and render the final video.

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I wish I could record using FRAPS, but it bogs my mediocre machine down so bad that the
frame rate resembles a slide show. So I use FSrecorder being it gives a much better frame rate,
but doesn't properly record all modes and such.

 

I use OBS. It has an associated performance hit, but it's not too bad. It's free/unrestricted/open-source.


Kyle Rodgers

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