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A320: flaps full or flaps 3+speed brakes?

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Old 2nd Oct 2008, 17:13
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A320: flaps full or flaps 3+speed brakes?

Hi all,
I´ve a question...in the case of being above the profile in the approach (too high) what would be more effective in order to correct that deviation...the use of flaps3 plus full speed brakes or the use of full flaps?
Thanks for your answers
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Old 2nd Oct 2008, 17:23
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If you are slow enough for CONF3, do you think that its wise to use FULL Speedbrakes?

Mutt
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Old 2nd Oct 2008, 17:28
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Personally I would use full flap and capture from above but if you are needing speed brake and full flap to capture a glide its probabaly a bit unstable.
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Old 2nd Oct 2008, 17:31
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Yes, I think CONF2, speedbrake and VS -1500 until G/S* then put the brake away and take the rest of the flap to slow down. I can't remember having got in a position that needed F3 and speedbrake. I think thats a go-around and try again situation. Althought I only fly 321s.
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Old 2nd Oct 2008, 17:41
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It also depends if you have the autopilot on or off. With the autopilot on you only get just over half spoiler deflection anyway. However with the autopilot off you will get full spoiler deflection.
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Old 2nd Oct 2008, 17:48
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Config3 and speedbrake.
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Old 2nd Oct 2008, 17:56
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Ok,
The situation is the following: visual app, A/P off, A/T off, F/D´s off.
You are too high and you don´t want to perform a go around so you want to descent as much as you can...
Forget about excesive rate near the ground or pax confort. My question is only about the aircraft performance.
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Old 2nd Oct 2008, 17:57
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The A/THR can misbehave on finals if speed brake is used with flap during the approach and G/S tracking during speedbrake extension/retraction can be very poor, leading to some 'interesting' pitch attitudes and rates of descent (and historically many destabilised approaches) as the aircraft reacts to the significant trim changes.


Gear down ASAP to decelerate the aircraft rapidly below VFE, Flaps to FULL, 160 kts until reestabilished. Or throw it away and do it again properly, and don't be in such a hurry to disconnect the automatics next time!
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Old 2nd Oct 2008, 18:17
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Almost every approach we do here in Turkey is ILS capture from above because of these darn ATC are keeping us high and bringing us in too tight...

Standard is always gear down asap and then config full asap! That's with A321's...
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Old 2nd Oct 2008, 18:27
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Just for info: you CAN get full speed brakes with A/P on in the 319...

But I personally find them quite useless when in config 3 or more.

I heard side slipping is great fun in the bus (you did say ignoring pax comfort)
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Old 2nd Oct 2008, 18:48
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electricdeathjet,

On the A320 you can't get full speed brake with the A/P engaged. Seems that the A319 is the same as the A321 as you can indeed get full speed brake with A/P on.

However the name of the thread implies that the thread starter was referring to the A320.
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Old 2nd Oct 2008, 19:46
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A321's speedbrake is inhibited with config 3 & full anyway, so kinda rules that one out.
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Old 2nd Oct 2008, 20:01
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too high

"DO NOT side slip the 'bus the pods are not designed for it". so speaketh the airbus top test man (several years ago)
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Old 2nd Oct 2008, 20:13
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Hey,

Use speedbrake to slow down to vfe -> conf full speed 160 with idle power gives high enough steep rates. Anything more would be too unstable.

Use of speedbrakes with conf full is not allowed (and with A321 in conf 3 too).

Olabade
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Old 2nd Oct 2008, 22:58
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If you can see that you're high on any sort of approach, but particularly a visual approach, it is more effiacious to select "VS 0", configure to CONF FULL, Gear Down and reduce speed to Vapp (this occurs quite quickly when level), then push forward to achieve a rate of descent which will re-capture your approach path to the runway by an appropriate altitude (to allow the engines to "spool up" by 500' AGL). Close attention must be paid to rates of descent approaching the ground (as a guide, VS-2000 at 2000', -1500 at 1500' & no more than -1000 below 1000').

It seems utterly counter-intuitive but given that CONF FULL is basically all drag and you've reduced your speed across the ground to an absolute minimum (Vapp), pushing forward at that point will provide the steepest angle of descent with all other factors required for landing (except Vapp since your speed will increase to not above 177 knots!) already accomplished.

This technique is best applied to visual approaches, since ILS, LLZ, GPS, VOR and NDB approaches (if conducted in IMC) have a higher "stable" requirement; in my company, we must be stable by 1000'AGL on an ILS, and the earlier of 2000' or the FAF on NPA's. If you're high enough to have to try to correct to profile using any unusual technique in IMC, you'll almost certainly be better off discontinuing the approach, or doing a go-around!
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Old 4th Oct 2008, 07:11
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Flaps 2 with the gear down and speed selected 190 knots, in OPEN DES, as thrust will be idle, she'll dive believe me. Tried and tested . You can correct any deviation. Ofcourse, this does not apply to being already established on the ILS, this only applies if you've been given very short radar vectors very suddenly. As mentioned in previous posts, especially in the A320, the best dive technique when you're far out is select speed 300 or 280, disconnect the AP and use full speed brakes. Spoiler deflection with the AP disengaged is 20 deg for spoiler 2 and 40 deg for spoilers 3 & 4, unlike 12.5 deg and 25 deg respectively when the AP is engaged (A320 only). A321, the maximum spoiler deflection is 25 deg whether AP engaged or not.

When trying to catch the glide from above, best rate of descent is V/S -1500 (AT THE MOST, or anything less) else u'll go past your Vfe next and you wont be able to configure
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Old 4th Oct 2008, 18:16
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To CABUS, post #3.

Just a reminder that in A-320, speedbrakes are (not PROhibited, but) INhibited in Full Flaps, meaning, you can pull the speedbrake handle back, but the panels will stay flush with the wing!

To Antonilo:
If it is during a visual approach, consider the following possibilities:
Extend downwind a bit,
Make the turn to final a bit wide, so you overshoot finals a bit, basically the S-turn that you make gives you some extra ground distance,
Extend the gear earlier (out of normal sequence),
Keep speedbrakes out while deploying flaps (as stated earlier, they will not deploy with Full Flaps).

All those actions should be taken IN TIME, discovering that you are too high and too fast at 3 miles final means that you screwed up earlier in the approach and you should make a go-around.
Consider this: 300 ft per mile is the norm (320 ft to be precise), so 30 nm to go at 10.000 is normal, 20 nm remaining at 10.000 ft can be handled.
The same relative error, 1.500 ft at 3 miles, instead of the required 1.000 ft at 3 miles, cannot be corrected anymore.


(Edited for a typo)

Last edited by EMIT; 6th Oct 2008 at 20:18.
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Old 5th Oct 2008, 08:49
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CONF 3, gear down, landing lights out, speed brake full - A320, managed speed. Aim to be stable at 1000, if not at 500 GA is mandatory. KISS & and works like charm.
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Old 5th Oct 2008, 09:28
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I agree with FD7, and it also goes for A330/340.

Flaps 2, gear down and Speedbrake with a selected speed and open descent is the only way to even make it from the downwind to final in SFO. They did it to me on a regular basis.

Nic
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Old 7th Oct 2008, 10:27
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Thanks everybody for the answers,
Most of you tell me that it´s better to extend downwind or use of flaps 3 or whatever to finally make a stabllished app.
The thing is that we fly many times positional fligths with no passengers so we can try "other things" so if I´m to high I like to fly feeling what can I expect from the aircraft (with safety of course)
My procedure usually consists in reducing speed and descent with flap 3 and speed brakes full (gear down aswell), what I´ve always think that was better than full flaps.
But recently I´ve flown with two guys that told me the opposite, and one of them told me that speed brakes are usefull at high speeds, but at lower speeds they loss effetiveness so is better to use flaps full.
I will ask my question in other way:
***What offers more drag, full speed brakes OR full flaps in comparison with 3?***
Sorry for extending so much...
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