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martinlest2

How to increase drag when descending?

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I think that with this a/c I shall have to employ spoilers to descend. They are not very subtle on this plane,
You have to use your mouse to grab the handle and pull it back to get partial speed brakes. If you hit the / key to activate them, you get 100% "not subtle". They can be subtle, but you have to use the mouse to do that. 

 

I'm not sure which a/c you are using, but if you hit <Shift> / before you land it will arm the speed brakes so that they will auto deploy when your wheels touch the runway. Do that while at cruise altitude and take note of where the handle stops in the armed position (you can press <Shift> / to activate and deactivate them while flying and nothing will change).

 

Now, when you need to deploy just a little bit of speed brake, use the mouse to drag the handle just a little bit past where the armed for auto deployment position is. You can kinda tell that the a/c is slowing by the "head bob" or viewpoint shift that FSX uses to simulate deceleration.  


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You have to use your mouse to grab the handle and pull it back to get partial speed brakes. If you hit the / key to activate them, you get 100% "not subtle". They can be subtle, but you have to use the mouse to do that.

Yes, that's what I do at the moment. Even with the mouse, a number of a/c have very 'jumpy' spoilers though, which seem to like to go to 100% with the slightest excuse: you have to be ultra-gentle. Other a/c work just fine...

 

I'm not sure which a/c you are using, but if you hit <Shift> / before you land it will arm the speed brakes so that they will auto deploy when your wheels touch the runway. Do that while at cruise altitude and take note of where the handle stops in the armed position (you can press <Shift> / to activate and deactivate them while flying and nothing will change).

I already have 'Arm Spoilers' set to my Saitek X52. What I am trying to do though is to programme spoilers to extend and retract incrementally, via FSUIPC (as 'advertised' as possible in the FSUIPC manual) and a key press (and hence to my X52). It's not working all that well at the moment, so I posted on the FSUIPC forum...

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I usually override the VNAV/DESCEND speed if it is above 250 and use  250 down to 10000 ft.

 

nebojsa

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Yes, I usually set my rate of descent manually too, so as to hit 250 comfortably at 10000'.

 

The FSUIPC works just fine in the end - I was testing on the ground (where incremental flaps won't work) rather than in the air (where it is pretty cool!). I mapped the key presses to one of my X52 buttons and so now I can increase and decrease spoilers in the same way as flaps.

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Regarding the use of speedbrakes, I find it hard to believe that there are airplanes in which you HAVE to use speedbrakes per manual to commence a descent, but hey, I'm not all-knowing and this could be, I just find it surprising. Having to use the speedbrakes is not ideal. Ideally you want to descend from cruize FL to the IAF without having to use the brakes because that increases fuel consumption, increases vibrations and is less efficient overall.

 

It all comes down to a lack of descent planning. If the aircraft you use is very slippery, start descending 20nm before the T/D, or even further out if that's not enough.. If you're using ASN or a weather program, put the winds into the FMC to get a more accurate descent profile.

 

I'm not saying here that using speedbrakes is bad, don't get me wrong. What I'm saying is that you want to avoid having to use them, but if for whatever reason you find yourself to close to the airport, to high and too fast, by all means use the spoilers. If you think that given the present profile you will have to use them, anticipate and use them BEFORE you get too high. It's even worse having to do a 360º, enter a hold, lose the entry slot or something like that because you didn't want to use them. In fact, if the situation is somewhat extreme, you could also drop the landing gear. Anything to get the job done (within reasonable of course)

 

 


I already have 'Arm Spoilers' set to my Saitek X52

 

I have the speedbrake lever mapped to the "slider" on the throttle of my Saitek X52. Works like a charm, even for arming the spoilers.


 

 


I usually override the VNAV/DESCEND speed if it is above 250 and use  250 down to 10000 ft.

Yes, I usually set my rate of descent manually too, so as to hit 250 comfortably at 10000'.

 

Or you can use FLCH (or the equivalent mode, in Airbus I think it's called OPEN DESCENT) and once you reach 11000ft roll the speed dial down from your ECON DES SPEED to 250. The aircraft will almost level out to slow down. It works very well.

 

Usually you don't want to slow down from cruise speed to 250 when reaching the top of descent.


Jaime Beneyto

My real life aviation and flight simulation videos [English and Spanish]

System: i9 9900k OC 5.0 GHz | RTX 2080 Super | 32GB DDR4 3200MHz | Asus Z390-F

 

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I find it hard to believe that there are airplanes in which you HAVE to use speedbrakes per manual to commence a descent

Me too. Surely in any case not the A350!! The 'manual' for this a/c is just the usual ReadMe.txt, so no information there.

It all comes down to a lack of descent planning

Well, not necessarily. I use PF3 for ATC and the descent planning is fairly sophisticated. What it really comes down to is an aircraft that will not descend, even at TOD, at more than about 7-800ft/min without accelerating, throttles at idle of course.

I have the speedbrake lever mapped to the "slider" on the throttle of my Saitek X52. Works like a charm, even for arming the spoilers.

I haven't in the past been able to map anything to the slider - how did you do it exactly, including arming, on the slider? I'd like to do the same. I have tried today using FSUIPC to create incremental speed brake extension/retraction, and it works up to a point in some aircraft - early days though, I only just started testing. My ideal would be to have the slider increase spoilers as you move it forward and decrease as you pull it back. I could use a different button for arming. Presumably yours is still an all-or-nothing affair, or do you also use FSUIPC to get incremental movement of the speed brakes??

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I haven't in the past been able to map anything to the slider - how did you do it exactly, including arming, on the slider? I'd like to do the same. I have tried today using FSUIPC to create incremental speed brake extension/retraction, and it works up to a point in some aircraft - early days though, I only just started testing. My ideal would be to have the slider increase spoilers as you move it forward and decrease as you pull it back. I could use a different button for arming. Presumably yours is still an all-or-nothing affair, or do you also use FSUIPC to get incremental movement of the speed brakes??

 

I do use FSUIPC, yes. Also make sure you have installed the Saitek DRIVERS, otherwise your PC won't let you configure every button (for example, I couldn't map the "i" button on the throttle until I installed those drivers).

 

I don't want to tinker with FSUIPC right now in case that I mess up and lose my configuration. I'm just telling you it's possible.

 

BTW: I have the slider in the opposite sense as you say. In the full "up" position of the slider, spoilers are stowed. In the full "down" of the slider, the spoilers are full up. This is to simulate the same movement of the lever in the real plane.


Jaime Beneyto

My real life aviation and flight simulation videos [English and Spanish]

System: i9 9900k OC 5.0 GHz | RTX 2080 Super | 32GB DDR4 3200MHz | Asus Z390-F

 

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It's OK, it is working just fine now, but only so far in my default a/c -  I've been using the 747 to set up and test. I have one of the switches on the X52 ("T4") set to spoilers up/down and one ("T3") to Arm Spoilers. It was also easy to programme the slider (why did I have trouble before? i can't remember, but no matter) and now it works brilliantly (though I got a BSOD at one stage during the testing!) - the spoilers move gradually from fully down to fully extended as you move the slider upwards to its full extent. Great!

 

'All' (?!) I have to do now (as I rarely fly default FS9 planes) is to see how to get it all to work like that in my add-on a/c like PMDG Boeings and PSS Airbuses. (In the PMDG I get no spoiler movement at all; in the PSS a/c, things work up to 1/4 spoilers, then they suddenly 'snap' to Armed mode. Did you get your slider to work with all your a/c OK (assuming you also use PMDG etc.)?

 

(Yes, the Saitek drivers and programming software are installed!)  :-)

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Regarding the use of speedbrakes, I find it hard to believe that there are airplanes in which you HAVE to use speedbrakes per manual to commence a descent, but hey, I'm not all-knowing and this could be, I just find it surprising.

Believe it! I think you are immagining full deployment. Cracking the speed brakes keeps the speed under control and does not increase vibration. And in any case it does depend on the a/c manual.

That siad you would certainly need full speed brake deployment in an emergency descent!

 

Next tiem you fly from the UK to Torino you will need full deployment once over the Alps to get down in time. Otherwise you will have to go an agrande tour on Northern Italy.

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Yes, when flying in the Alps or Himalayas to get down between mountain peaks, but we are talking about a 'normal' scenerio descending from say 38000' when flying, for instance, Amsterdam to Moscow, no sudden drops necessary. Aircraft do not normally require any spoilers at all right from the TOD, assuming throttles are on idle and a standard -3 degrees AoA.

(though I got a BSOD at one stage during the testing!)

Got another one as I move the sliders (x07E - Saik075C.sys). A bit worrying.

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and a standard -3 degrees AoA.

 

Actually the Angle of Attack stays the same as during the cruise, assuming the same initial descent speed. In the transition from level to descent, it will vary (there's accelerations), but once established on a steady 1-g descent, the AoA will be the same as the one you had in level flight.

 

What you meant was a 3º glide path. If you use the Flight Path Vector (FPV), you'll indeed see it in a negative angle during a descent. But the nose of the aircraft will generally be pointing at the horizon or even slightly above.

 

Just a flight mechanics note at the risk of being too "perfectionist" :)

 

 

Believe it! I think you are immagining full deployment. Cracking the speed brakes keeps the speed under control and does not increase vibration. And in any case it does depend on the a/c manual.

 

Indeed, one learns new stuff every day! Thanks!


Jaime Beneyto

My real life aviation and flight simulation videos [English and Spanish]

System: i9 9900k OC 5.0 GHz | RTX 2080 Super | 32GB DDR4 3200MHz | Asus Z390-F

 

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What you meant was a 3º glide path

Yes, I did! Don't know why I put 'AoA'... :smile:

 

I find sometimes with the slider that, although pushing it to the top extends the spoilers fully, bringing the slider back down again doesn't bring the spoilers fully down, I have to use the associated key press to complete the task

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