Airbus aircraft sidestick target on PFD

[granard]

How do the pilots use the target cross on the PFD ?
Appears after engine start and disappears after take off.
Im not a pilot and i was wondering how it was used.
Thanks

Thanks for all the replys.

What are we agreeing to as the correct use of the indication?

[Checkboard]

I use it to position the ailerons into wind at rotation on a cross wind takeoff.

[hetfield]

I use it to position the ailerons into wind at rotation on a cross wind takeoff.

Really.....?

[Uplinker]

The white Maltese cross and box on the PFD (Primary Flight Display) are used during the flight control check.

The box represents maximum sidestick deflection. During the control check, one pilot will move their sidestick to the limit in all directions in sequence. The other pilot watches this and checks that the correct flight controls, (ailerons, spoilers, elevators and rudder), move the correct amount in the correct direction on the flight control page, which is automatically called when the flying controls are deflected during taxy out.

On take off, the cross and target remain until about 50 or 100' above the ground, (can't remember which), so the Pilot Monitoring can see the control inputs being put in by the Pilot Flying.

{Further to the AF447 crash, I made the suggestion on that thread that during flight this visual be replaced on the PFD's in flashing red if a sidestick was ever held at a limit for more than say 5 seconds, so the other pilot could see what the pilot flying was doing with the sidestick.}

[EGPFlyer]

hetfield,

During takeoffs with very strong crosswinds some aileron may be required to keep the wings level. You don't want to go so far as to deploy the spoilers so the cross can be used to ensure side stick deflection is no more than a third. It's all in the FCTM.

[hetfield]

Don't have any FCOM A320 since 1998.

If AB became wiser and has changed this subject, I apologize my comment.

[CONF iture]

On take off, the cross and target remain until about 50 or 100' above the ground, (can't remember which), so the Pilot Monitoring can see the control inputs being put in by the Pilot Flying.
You apparently don't monitor yourself a lot then ... At 50 the cross has gone for a while already.

[OLG]

speaking of which: anyone happens to have a reference about what exactly triggers the double crosshair ("sidestick order") to disappear from the PFD after airborne?

I tend to feel that on newer (MSN 4000++) aircraft is disappears somewhat earlier than on the older ones (MSN 1000-) but I could not find an exact reference in the FCOM.

Cheers

[CONF iture]

During takeoffs with very strong crosswinds some aileron may be required to keep the wings level. You don't want to go so far as to deploy the spoilers so the cross can be used to ensure side stick deflection is no more than a third. It's all in the FCTM.
It is in my FTCM to avoid deploying spoilers on one side. But it is not specified to use the cross for that matter ... Would you have the precise quote to state so from yours ?

[A320baby]

I heard A rumour that Airbus are looking into ways of making the Airbus more Crosswind friendly. Ie more leigh way with sidestick vs spoiler deflection, Is there any truth in this?

[Uplinker]

You apparently don't monitor yourself a lot then ... At 50 the cross has gone for a while already.

Well call me old fashioned, but I am usually more concerned with; positive climb - gear up - monitoring PF's flying - noise abatement turns etc. to notice exactly when it goes.

I will check for you next time I fly.




U

[EGPFlyer]

FCTM
For crosswind takeoffs, routine use of into wind aileron is not necessary. In strong crosswind conditions, small lateral stick input may be used to maintain wings level, if deemed necessary due to into wind wing reaction, but avoid using large deflections, resulting in excessive spoiler deployment which increase the aircraft tendency to turn into the wind (due to high weight on wheels on the spoiler extended side), reduces lift and increases drag. Spoiler deflection becomes significant with more than a third sidestick deflection.

The reference to the cross position is from our company issued training study guide. It states that the limit of sidestick to avoid spoiler deployment is when the edge of the cross is on the central index.

[Chris Scott]

Hello chaps/chapesses,

In case it's of interest, and at risk of irritating those who have seen it before, I wrote this as part of a post (http://www.pprune.org/tech-log/316096-lh-a320-rough-landing-hamburg-24.html#post3979423) in 1988. It came out of a general discussion on A320 crosswind handling, and was much assisted, IIRC, by Confiture and Lemurian (interesting combination!). Unofficial,of course, and no FCOM or FCTM references, I'm sorry to say:

"CROSSWIND TAKE-OFF
A small amount of into-wind aileron can be selected before starting the T/O run, avoiding "cracking" the spoilers.* During rotation, the upwind wing tends to rise in the conventional manner, and can be countered by retaining into-wind aileron. As the main L/G lifts off, any downwind rudder will be eased off, yawing the aeroplane into wind. This will temporarily assist the aileron. Half a second after lift-off, however, Normal Law in roll is introduced (AND the white cross on the PFDs has disappeared). At that point, any remaining roll input needs to be released.
"5 seconds after main L/G lift-off, Normal Law also becomes fully effective in pitch. Stick-to-elevator control is now removed, and pitch-attitude can be refined by small nudges of sidestick.

" * Roll-spoiler deployment can be avoided by placing the PFD white-cross so that its inner edge is not noticeably to the side of the centre spot."

Now, 5 years later, I realise that I neglected to mention the need for some forward stick on all take-offs, particularly I suppose on a wet crosswind one. This makes it a bit more difficult to judge how much roll (aileron) command you are selecting, and to avoid "cracking" the spoilers. If in doubt, however, you will notice that the F/CTL page appears briefly when you first displace the stick, and enables you (if you are ready for it) to confirm that the spoilers are still stowed. If you miss it, briefly select the page manually.

Regards,
Chris

[nitpicker330]

I agree 100% with Smash Bugger

It's not used for Flight Control checks, the PM looks at the Flight Control page to monitor the controls. The Maltese cross is only for the PM to monitor what the PF is doing on the ground.

[Uplinker]

As has been discussed ad infinitum on other threads, you cannot always see what input is being made to the opposite sidestick.

If a sidestick had been replaced and wired up backwards (it has happened), then the sidestick might be moved say full left but the controls might go full right. Or a flight computer might have a fault which reverses the sidestick inputs. By crosschecking the maltese cross with the flight control page, I am double checking that the sidestick direction and the flight controls are moving in the same sense.

My original answer to the OP was: During the control check, one pilot will move their sidestick to the limit in all directions in sequence. The other pilot watches this and checks that the correct flight controls, (ailerons, spoilers, elevators and rudder), move the correct amount in the correct direction on the flight control page, which seems pretty clear to me?


U

[split system breaker]

Erm, it's just a point, but the side-stick position indicator on the PFD is just that, it's not a target for anything.

And, it's not a Maltese cross anyway; that consists of 4 isosoles triangles joined at the centre; if anything it's a German cross.

so there.

[Uplinker]

Thank you SSB for that wonderfully enlightening post. I'm sure we are all much clearer now. Thanks.

I sincerely hope that neither you nor anyone else ever gets a control reversal caused by a faulty sidestick, ELAC, SEC, or PRIM, but with my past knowledge and experience as an electronics engineer, I will continue my double cross-checking. :)


U

[granard]

From my research smashbugger explanation is what I found .

[nitpicker330]

So you're suggesting that while I Taxy the Aircraft I look down watching the cross on my PFD while the PM also goes heads down watching the Flight Control page to check each surface moves the correct way????????

That sounds like a good way to come to grief. :{


From the A330 FCTM:---


“Flight Control Check”

PM -Monitor F/CTL page.
PF -Apply full back sidestick followed by full forward sidestick, then release.

PM - "Full up, full down, neutral"

PF -Apply full left sidestick followed by full right sidestick, then release.

PM- "Full left, full right, neutral"

PM -Monitor F/CTL page. Follow through on the rudder pedals to confirm full and correct movement.

PF -Press the PEDAL DISC pb on the steering handwheel, smoothly apply full left and full right rudder and then return the rudder to neutral.

PM -"Full left, full right, neutral"

Ensure that the PM calls are in accordance with flight control inputs

PM Move you own Sidestick as above calling out movements etc.


It's not Rocket Science people.:ok:

[Uplinker]

Strewth, why is this so difficult?

No; the pilot taxying is taxying - eyes out of the cockpit.

Pilot monitoring has eyes inside the cockpit for the control check. PT says 'control check' I look at the GERMAN cross to see what the opposite sidestick is demanding, then I look at the flight control page to see and confirm that the correct flight controls have moved in the correct direction and by the correct amount.

Yes, if PT moved full left and PM saw and called full right, they would both know there was a problem. But what if PT was tired after a long day, and on the 6th sector there were distractions during taxying and did not register that when s/he pulled full left, PM called full right?


U

[nitpicker330]

What if the guys misread the cross too..........:E

Besides you can see the other crew member stirring his stick out the corner of your eye.........:eek:

[Chris Scott]

Guys....

As so often happens, several of you have gone off at a tangent; getting into a heated argument about a side issue. In the meantime, I've contributed a thoughtful post (see previous page) which directly answers the question originally posed by granard.

granard has since edited his post, and asks:

"Thanks for all the replies.
What are we agreeing to as the correct use of the indication?"

Any comments?

PS
Provided the PF does not rush the flight-control check, it's a cynch for the PNF to monitor both white crosses reaching full deflection, as well as the appropriate control responses on the F/CTL page. The PF simply holds the stick at full deflection until the PNF is satisfied, which he indicates by whatever verbal response is defined in your airline's SOPs. The PF then releases the stick. When it reaches neutral, the PF waits for the PNF to confirm that the flight controls (and both white crosses) have returned to neutral.

[Checkboard]

Pilot monitoring has eyes inside the cockpit for the control check. PT says 'control check' I look at the GERMAN cross to see what the opposite sidestick is demanding, then I look at the flight control page to see and confirm that the correct flight controls have moved in the correct direction and by the correct amount.
What makes you think that the system which displays the GERMAN cross will show a different indication to the control deflection? If there is an error, it will affect both presentations in the same sense.

[C212-100]

Should be used, while PM, to confirm side stick neutral at the "100 knots" callout during the take-off roll. Also useful to check if the PF applies back stick at Vr.

Cheers.

[Uplinker]

What makes you think that the system which displays the GERMAN cross will show a different indication to the control deflection? If there is an error, it will affect both presentations in the same sense.

OK. Let us suppose the output of the sidestick is sent on a data bus or wires both to the DMC's, which generate the white crosses, AND the flight control computers, which of course move the controls. However, let us suppose that either the DMC or a flight control computer has a fault internal to itself, (for example a dry joint)*, which reverses the sense of the sidestick - hey presto, one system thinks 'stick left' the other thinks 'stick right'. The box appears after engine start (i.e. before taxying), and not on application of take-off power - why would that be if it was not to provide sidestick position info during taxying?

That's my logic for my extra check, (which by the way takes all of half a second to perform). From what I know about electronic circuits and dry joints etc., this is what I will continue to do.


The OP wanted to know what the white cross was used for. I think that myself and others have answered their question.


U


*For those who may not know; a dry joint is a faulty electrical soldered connection in a circuit, which results in an intermittent electrical connection. Sometimes the joint is electrically sound, other times it is open circuit. These joints can and often do look perfect to the naked eye, and when electrically tested can appear sound. However, when the circuit heats up to operating temperature the joint can go intermittent. Dry joint faults are very difficult to trace.

[Natstrackalpha]

quote:
The Maltese cross is only for the PM to monitor what the PF is doing on the ground

unquote.

Not really!!!

U is right on, obviously flying 330.

The sidestick cross indicates the position of the sidestick.
Is used by the Pilot Flying during takeoff.
For example: Half scale Deflection downwards, until 100kts during the takeoff roll when it is placed on the horizon line on the PFD.
Then aids stick position indication when rotating to the appropriate angle at VR.
As mentioned, during crosswind takeoffs the sidestick is deflected to half a cross deflection (into wind) until, as described above, the aircraft rotates and weathercocks into wind, as in a conventional x-wind takeoff. . .
after which the cross disappears.
Some, operators prescribe full cross down in a crosswind takeoff with the into wind input, I don`t like this method, but is the way to do it whether I like it or not.

:added later . . .My point, though perhaps poorly laid out, is, that, the white cross is an indicator of sidestick position as opposed to anythingelse, like, flying controls.

And, the original question is/was: "How do the pilots use the target cross on the PFD ?" And, the answer is what I have written above.

ton pi

[CONF iture]

Is used by the Pilot Flying during takeoff.
You would be welcome to quote your FCTM if and how it states so ?

Then aids stick position as an indicator when rotating to the appropriate angle at VR.
You have obviously also missed a notorious serious incident report.
Cross is certainly not to be used by the PF for rotation.


You are definitely correct Chris, the initial Q. What are we agreeing to as the correct use of the indication? needs further consideration ...

[woodja51]

For info the SSI / maltese / german/ swiss cross etc... Used to disappear after ground to air switch over... Then Emirates had a near hull loss as the crew used (wrong) training info during a takeoff out of
Jo berg some years ago... You can read about that somewhere else i guess.. After that incident AB modified it to disappear at NW extension ... You can verify this in the sim if youload the aircraft really aft in Cog and may note on a rough runway setting that it drops in and out as the aircraft goes light on the NW ...

i think all aircraft should be modded like this now but could be wrong..

Most of the remaining posts are pretty spot on regards limited use/ value to most parts of the operation.

WJA

[CONF iture]

For info the SSI / maltese / german/ swiss cross etc...
Nobody seems really to agree on the way to call it after all but is it that surprising when Airbus itself names it Sidestick Order Indicator in the FCOM but Stick Cross Symbol in the FCTM.
On the same order, its function is also ambiguous and has evolved following serious incidents. Was it avail at all airborne in the early days, maybe for a few seconds after take off ... Chris ?
Now its time for being displayed has been reduced to a minimum and the advise not to use it by the PF during take off is clear.
The single note I can see to promote its use is addressed to the PM to validate the PF initial stick input. Interconnected sidesticks would do that nicely and much more.

[Chris Scott]

Salut Confit,

Regret I cannot remember exactly when the "white cross" (as I usually call it) disappeared after take-off. And I don't know if the logic ever changed. I don't remember ever watching the white cross after 100kts, even as PNF.

As you know, the only Airbus FBW I flew was the A320 family, but I'm very interested in woodja51's post. Until now, I have assumed that disappearance of the white cross may be part of the logic of the introduction of Roll Normal, and the gradual introduction of Pitch Normal. My old FCOM says these two processes start when the a/c becomes airborne, which implies the main L/G weight switches. But we know that the nose L/G also has weight switches, and woodja51 says the disappearance of the cross is now on that. I presume this may not apply to the A320 family?

So, woodja51, what about the control laws switching? Presumably, that still uses the main weight switches?

Returning to the original question, I think the white cross is useful for the PF at the very start of the take-off run (partly down, and not too much left or right). At 100 kts, when the PF has finished releasing the down-input, he/she may want to glance briefly to check that the desired aileron (if any) has been maintained. After that, forget it.

[woodja51]

Chris ,

Not able to answer your flight control changover regarding WOW switches.

Have I missed something but does the FCOM not say half stick forward on take off to ease to zero at 100 kts except when xwind > 20 kts or any downwind then to use full forward stick ?

This is a 330 of course so could be diff on other types....

Hlaf stick is where the stick spring pressure increases or half a cross down by my reckoning. The same spring pressure increase in aft stick provides a good tactile input to correct rotation input to commence with from what I was told and do ... Before the cross disappears it will get to about 10degress NU before the jet starts to react and NW comes off... Assuming a 2.3-3 deg pitch rate or so...

Is that of any assistance ? Oh and the small left / right input should be eased out too and allow roll normal to control the drift effect as the rotate proceeds from what I was lead to believe.... Seems to work to me in 6000 hours in the LHS on it.

[Easy226]

Pitch and lateral control switching (ground - flight) is not related to weight on wheels. The trigger is when the pitch attitude is greater than 8 degrees. At this attitude, the timing starts for a gradual transition from ground to flight mode. That's how I read my (A320) FCOM anyway!

I don't think the side stick indicator logic on the fleet I fly has been updated on all variants and cannot find the memo we were sent a while back about this. The newer aircraft have a new DMC standard (green VDEV scale on PFD in DES) and I think the new logic could co-incide with this standard.

[Uplinker]

Thanks Natstrackalpha. :ok:

Having recently flown, (A330), I agree that the white sidestick position indicator does now disappear soon after rotation.

So: You apparently don't monitor yourself a lot then ... At 50 the cross has gone for a while already. Yep; Confit; you're right.

However, I'm sure that some old A320's I used to fly kept the indication to 50 or 100', because I remember using it to watch what PF did with the controls during take-off and rotation when I was learning to fly the thing.

Another reason for the white sidestick position indicator being displayed on the take-off roll is of course to monitor a sidestick fault. If a sudden control hard over was seen, PM could shout stop! (below V1).

U

[Chris Scott]

Hi woodja51,

I can't be of much more use in this discussion, because the last time I was in an Airbus FBW cockpit was the end of 2001! Prior to that, I was a line capt and line checker for 14 years, but only on the A320/A319. So even my A320 FCOM and Training manual are way out of date. I think we used to use half down-elevator, judged by placing the white cross half way down, until 80 kts (as per my post #14 (http://www.pprune.org/tech-log/506282-airbus-aircraft-sidestick-target-pfd.html#post7658312), above). Can't remember if we ever modified our policy to use extra for strong crosswind or downwind, but obviously see the argument; particularly on a wet runway, where nosewheel adhesion is important while the rudder-fine steering is available. Even at zero IAS, the down elevator is of some effect for take-off on the A320, due to the slipstream effect.

Quote:
"Half stick is where the stick spring pressure increases or half a cross down by my reckoning."
Which is it? Half stick or half a cross? Half stick puts the whole cross well below the black box, IIRC.

Quote (my highlighting):
"Oh and the small left / right input should be eased out too and allow roll normal to control the drift effect as the rotate proceeds from what I was lead to believe.... Seems to work to me in 6000 hours in the LHS on it."
Yes. One of the commonest handling mistakes I saw - often from the P3 seat on line-checks - was the upwind wing rising during rotation. The theory in the early days on the A320 was that Roll Normal would prevent that happening, but it quickly became apparent to me that this was not the case. The wing would rise immediately rotation was started, before main L/G lift-off (as you would expect). However, many of our trainers clung on to their assumption in the face of all the evidence... :{

[Right Way Up]

Very simple for me.

Until airborne I can ensure as Captain that the f/o is not putting too much lateral control - see Air2000 Bristol tail strike, and then I can monitor amount of backstick in rotation.

[CONF iture]

Until airborne I can ensure as Captain that the f/o is not putting too much lateral control - see Air2000 Bristol tail strike, and then I can monitor amount of backstick in rotation.
What is your opinion then on the Ziegler's concept on which Airbus is built that the other pilot don't need to know how the PF is soliciting the flight control commands ?

[Right Way Up]

Hi CONF iture

I think over the years it can be seen that there have been certain flaws with the concept of the Airbus design. My job is to use best resources to safeguard the aircraft. That includes on day 1 of line training a 200 hour cadet, keeping an eye on his/her initial control inputs. Would not be the first time I have had to takeover during rotate as the f/o has full back stick. If I waited till airborne (ie not monitor the cross) it would be too late.

[granard]

So with all the comments that have being made, what is the final use of the white cross?

Is it to allow the PF to observe during takeoff the amount and direction of the side stick and at the same time to allow the PNF to observe the PF inputs.

[CONF iture]

Yes. One of the commonest handling mistakes I saw - often from the P3 seat on line-checks - was the upwind wing rising during rotation. The theory in the early days on the A320 was that Roll Normal would prevent that happening, but it quickly became apparent to me that this was not the case. The wing would rise immediately rotation was started, before main L/G lift-off (as you would expect). However, many of our trainers clung on to their assumption in the face of all the evidence...
But Roll Normal is not fully active before 2 sec after attitude is over 8 deg. Until that time the roll is still under Ground Mode when aileron deflection is proportional to Sidestick deflection. As you state, pilot's action is necessary to prevent the upwind wing to rise during rotation.

Would not be the first time I have had to takeover during rotate as the f/o has full back stick. If I waited till airborne (ie not monitor the cross) it would be too late.
The rule seems to be now that the white cross disappears when the Nose Landing Gear is fully extended. Are your aircrafts still displaying the white cross up to the Main Landing Gear extension ?

[Right Way Up]

Good question....not sure as once wheels off ground I am more interested in the change of flightpath. My gut feeling is that it disappears during the transition to flight mode.

[CONF iture]

But what says your manual FCOM DSC-27-20-30 ?
Still last year we had a mix in our fleet, but lately all aircrafts have been standardized and the white cross has already disappeared for the rotation process itself.

[Right Way Up]

FCOM tends to be irrelevant as depending on age the aircraft tend to be different. Once I see the initial input in rotation I look outside.

[CONF iture]

FCOM tends to be irrelevant as depending on age the aircraft tend to be different.
It should not be the case as FCOM are updated at the same time a software is modified whatever the age of the aircraft.

[Chris Scott]

Quote from CONF_iture:
"But Roll Normal is not fully active before 2 sec after attitude is over 8 deg. Until that time the roll is still under Ground Mode when aileron deflection is proportional to Sidestick deflection. As you state, pilot's action is necessary to prevent the upwind wing to rise during rotation."

Bien-sure, although I certainly could not confirm that your precise figures (2 seconds after Pitch +8) are the same for the A320, and my FCOM is way out of date. I think the most likely time for the wing to rise is when the wing starts to "fly", but the main wheels are still providing directional stability. At that stage, the a/c is still, in effect, side-slipping in the crosswind, and roll control is still stick-to-aileron/spoiler.

My own practice was to retain the original aileron after 100 knots, and be prepared to increase it (if necessary) during rotation until Roll Normal law kicked in. Better to have a brief extension of the spoilers during rotation, than for the a/c to roll downwind.

[Right Way Up]

For all 200 odd of our aircraft:

On the ground, after the first engine start, sidestick position indications appear white on both PFDs. The indications disappear when the aircraft goes from the ground into flight.

There have certain technical aspects in the past not reflected by FCOM.
i.e. that an aircraft in alternate law will not always go into Direct Law when the gear is extended!

[CONF iture]

Bien-sure, although I certainly could not confirm that your precise figures (2 seconds after Pitch +8) are the same for the A320
Correct, apparently the time is only half a second for the 320.


see Air2000 Bristol tail strike
Was it due to a too aggressive rotation or to an erroneous VR speed ?

[Right Way Up]

Synopsis of the Air2000 incident.

had initiated rotation at the correct speed but he had rapidly applied appreciably more rearwards side-stick than any other pilot within a sample of seven other flights. He had also applied a large lateral side-stick deflection before and during rotation which was sufficient to deploy the roll spoilers on the left wing. Spoiler deployment during rotation has two undesirable effects: it decreases wing lift and it increases the nose-up pitch rate. The combined effect of the aft and lateral side-stick inputs was a sustained pitch rotation rate of more than twice the recommended rate of 3°sec.

[Vc10Tail]

This symbol is a signature of Ground law being in force and disappears when ground law is no longer valid. It is a pointer of rate of side stick movement by the handling pilot. It is a cursor that is a visual indication of side stick movement and allows monitoring of the side stick deflection against max deflection limits as demarcated by the white partial box on the face of the PFD during Ground law mode after engine start.Is used as ref during flight control check deflections.

[CONF iture]

Synopsis of the Air2000 incident.
Thanks, I have found the report now.
Interesting to note that the PF was not a low time guy but a captain with TT5000H and half of it on type. Because we may all need supervision, whatever our experience, depending on the conditions and the fatigue state. The Sidestick concept by Airbus suppresses a valuable tool for natural and easy supervision.

[DozyWannabe]

Question - if the PF was a Captain with 5000+ hours, what reason would the PNF have had to follow through on the PFC during the roll and correct where necessary?

[CONF iture]

If the PF was a Captain with 5000+ hours, what reason would the PNF have had to follow through on the PFC during the roll and correct where necessary?
Inadequate control inputs are not exclusive to low time pilots, even 20000 hours guys can make some. The Pilot Monitoring is called so for a reason.

[greenspinner]

QUOTE FCOM Rev Dec 2012
Ident.: DSC-27-20-30-00001094.0001001
Applicable to: ALL
On the ground, after the first engine start, sidestick position indications appear white on both PFDs.
The indications disappear when the aircraft goes from the ground into flight.

[woodja51]

Flew a 330 -300 today with very aft loading ... As per my previous post about NW extension inhibiting it, this is exactly what occurred as we bounced down the runway and the nose wheel bounced a liitle up and down,.. The stick and boxed corners of its travel limits came in and out a few times... It also dissappeared again once a rotate had been initiated , last seen at about 8 deg up stick as the rotate progressed. Wja

[granard]

From more research I got this answer!

The main goal of the sidestick position indications is to keep the PNF aware of the inputs made by the PF when there is no aircraft response upon these inputs, which is the case on ground only. This indication is for PNF awareness in general.

For example, during flight control checks, the crew has to verify that the flight control surfaces go to the full deflection and in the correct direction (PRO-NOR-SOP-10-A). The full deflection is to be checked on the ECAM F/CTL Page. To check that the deflection is in the correct direction, the PF will compare the sense of his/her action on the side stick with the callout made by the PNF. The PNF primary task is to check the surfaces deflection on the ECAM F/CTL page and to announce its direction. However, the PNF may additionally compare the direction of the displacement of the deflection of the surfaces on the F/CTL page with the direction of the side stick symbol on the PFD.

The sidestick position on the PFD may also be used by the PNF (not the PF) during initial takeoff roll to check that the PF is making an appropriate control input. Please note that this indication must not be used by the PF during takeoff rotation.

We hope this satisfactorily responds to your request. We encourage you to provide us with your feedback using the questionnaire below, and we remain available for any additional information and assistance.

[Natstrackalpha]

You have obviously also missed a notorious serious incident report.
Cross is certainly not to be used by the PF for rotation.


I think I remember the incident, sometime ago during takeoff?

To cut a long story short, if I have the same story - the resultant factor was that the PF was not using the cross as a stick indication, which I am sticking to, but, that he used it as an aircraft pitch ATT indication, if I am right.

Also, rather unnervingly - an instructor once told me in a sim session, that if I place the cross on the pitch angle I want, on the . . artificial horizon (pitch bar) then the aircraft would pitch to that . . pitch attitude or alpha.
For example, he meant, if I placed the cross on the 10 degree pitch bar then I would pitch up to 10 degrees nose up.

I have a tiny inkling that this is complete and utter :mad:.

But please correct me if I am wrong.

[Uplinker]

Sounds very dodgy - by which I mean anyone using the white cross as any sort of flight indicator/director is barking up the wrong and very dodgy tree.

The White cross is NOT a flight director, NOR is it any sort of aircraft attitude indicator. The white cross shows the sidestick position ONLY.

I guess this potential confusion, (although frankly it beggars belief), might be why Airbuses now remove the white cross very soon after rotation.

[Chris Scott]

Quotes from Uplinker:
(1)
"The White cross is NOT a flight director, NOR is it any sort of aircraft attitude indicator. The white cross shows the sidestick position ONLY."

Indeed. Describing the white cross as a "sidestick target", as in the title of this thread, is misleading. I'm not sure where the OP got the expression from, actually. It's 11 years since I flew the a/c, but my original A320 FCOM, dated Feb 1988, describes them (one per PFD) as follows:

"On ground, side stick position indications appear white on CPT and FO PFD."

(2)
"I guess this potential confusion, (although frankly it beggars belief), might be why Airbuses now remove the white cross very soon after rotation."

Yes, but you could omit the "now". As one of the first line pilots to fly the A320 (March 1988), I can assure you it was ever thus.

[CONF iture]

Yes, but you could omit the "now". As one of the first line pilots to fly the A320 (March 1988), I can assure you it was ever thus.
There is a difference here as the white cross used to disappear when main gear oleos were fully extended but now, the white cross disappears as soon as the nose gear oleo is fully extended, at least on the 330s I know.
IOW the white cross used to be displayed for the full rotation, but not anymore.
As mentioned earlier by woodja51, depending on the CG, THS setting, RWY surface, the white cross can already disappear or at least blink during the take off roll.

[Chris Scott]

Quote from CONF_iture:
"There is a difference here as the white cross used to disappear when main gear oleos were fully extended but now, the white cross disappears as soon as the nose gear oleo is fully extended, at least on the 330s I know."

Yes, the logic may have changed very slightly, and it seems to be subtley different on the different types - I don't think we've precisely nailed that one. I was simply responding to Uplinker's less specific point that "Airbuses NOW remove [it] very soon after rotation" [my emphases]. I don't think we would argue with that as a pilots' practical description?

But I wanted to emphasise that, at any rate since A320 type certification in February 1988, the white cross has never been visible for a significant period after rotation.

Quote from OK465:
"Just a technical point, but the cross represents SS 'commands' in effect, not necessarily SS position."

Yes, as in the famous incident where an a/c came off maintenance with the transducers on one sidestick cross-wired (connectors not Murphy-proof). My quote was from a FCOM that predated that incident by many years!

Do we all agree that to call the white cross a "TARGET" is misleading? What do the current FCOMs call it?

[phd111]

Nowhere in the FCOMs is the white cross on the PFD referredto as the ‘Maltese‘ cross, although it does resemble the George Cross on the Maltese flag.

The Maltese cross isan eight pointed cross similar to the FAF symbol on Jeppesen charts.

[WhyByFlier]

It's referred to as a sidestick order indication.


FCOMDSC-31-40 P 2/36

[/QUOTE](1) Sidestick order indication: This symbol is in white, and appears as soon as one engine is started. It indicates the total of the Captain's and First Officer's sidestick orders (shown here as left wing down, pitch up).[/QUOTE]

[CONF iture]

Just a technical point, but the cross represents SS 'commands' in effect, not necessarily SS position.
I'm not too sure about that ...
In the FRA event, I believe the Side Stick Indicator was moving accordingly to the CPT sidestick displacement. Only the direction of deflection for the flight controls were reversed.
The lateral control of the aeroplane was checked in accordance with the AFTER START CHECKLIST only for full deflection but not for the correct direction of deflection.

[junebug172]

I use the cross for one reason - to gauge half-stick input for TO. We start to wash out the forward stick input at 80 KTS to be neutral by 100.

For 20 KT+ crosswinds, our primary input is full stick forward with the same wash out as above. Aileron input is discouraged because of the potential for spoiler float - basically no more than than half the width of the cross from center.

And it disappears once the mains come off in an A320.