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320p
25th Mar 2009, 04:53
Hello,
The VOR/ADF selector on the FCU also has OFF position .I have noticed some pilots after landing select the OFF postion,though it is nowhere mentioned in the FCOM.
My question is :
1. What does the OFF postion do and is this action of selecting OFF postion after landing correct?
2. Does it switch off the VOR/ADF as some believe(though the MCDU does still show the Radioaid) or it just removes the display from the ND.
Thanks

bflyer
25th Mar 2009, 05:36
Hi

I operate in the middle east and i have noticed that some of my collegues do it as well.. as you have said, i have seen no reference t it in our s.o.p and found no obvious benefit from this action such as saving equipment...etc, maybe they know something we don't :confused:
Anyway, since you brought up the subject i will ask around, but i suspect that the reason might simply be to leave the collegue who's going to pick up the aircraft with the choice of selecting his own choice?:confused:
Also dosen't make any sense
I will ask around
cheers

Parity
25th Mar 2009, 06:56
The ADF/OFF/VOR on the EFIS control panel selects what is displayed on the ND. It does not control operation of VOR or ADF receivers. For example with both Captain's and F/O's EFIS switches selected to OFF either VOR or ADF data can be displayed on the DDRMI

Jofm5
25th Mar 2009, 07:12
My apologies as asking this as SLF.....

But the whole point of CRM is for you not to feel inhibited in questioning your colleagues actions. I work in a different line of work but similar rules do apply - Do not feel embarassed about asking a question no matter how trivial cause hind sight is the only thing that does make it trivial.

Bite the bullet and say hold on - Why ? and you will get an explanation, it may be good it may be bad - but you live and move on and are more educated

If you cant ask questions your not sharing, if your not sharing your not learning and if your not learning then your doomed.

Sorry for my pessimistic approach but as a software dev - we work on similar principles

PENKO
25th Mar 2009, 07:54
It's an easy mistake to have the wrong needles pointing in the wrng direction at the worst time (one on ADF as a leftover from the take off, when on approach both should be on VOR for example). That's why I try to make it a habit in the climb to switch both needles OFF, so that during the approach preparation I have to make a conscious effort to re-select the correct boxes. It's a small silly personal rule, but as I said, it's an easy mistake to make in an automated flightdeck where all the tuning is done via the MCDU.

Anyway, even if you switch them all OFF on the FCU, the SBY RMI is still pointing to your selected VOR/NDB's, so there's your answer without even looking in the FCOM!

TyroPicard
25th Mar 2009, 12:03
PENKO..
That's why I try to make it a habit in the climb to switch both needles OFF, so that during the approach preparation I have to make a conscious effort to re-select the correct boxes. It's a small silly personal rule, but as I said, it's an easy mistake to make in an automated flightdeck where all the tuning is done via the MCDU.

With the switches OFF how do you monitor flight progress? I was taught, and teach, the use of raw data as a backup throughout the flight, which in most parts of the world means VOR only in the cruise. If you develop awareness of the tuned aids - you will have better awareness of the switch positions required at various stages of the approach, and you won't make those easy mistakes.. or if you do you will spot them.

Graybeard
25th Mar 2009, 13:12
Doesn't the Boeing EFIS have separate, distinct pointers for VOR and ADF? Seems like one more chance for confusion; something about modality.

PENKO
25th Mar 2009, 14:22
TyroP, apologies if my post is unclear, was probably thinking faster than I can type. What I meant is that by switching the pointers off after TO I subsequently have to make a conscious effort to switch them back on in the correct way during the approach. I will then have a fresh mental picture of what is pointing to where.

If I leave them in the TO setting, there will be a day, on a rushed and stressed approach on the fourth flight of a fifth early, on which I will have programmed the whole aircraft through the FMS (MCDU) forgetting to point the pointers correctly..which might lead to mistakes.

I know it sounds a bit ott, and also on the Bus the pointers have their separate shape and color. Still, a mistake is easily made, and this is my way to prevent it. That's all. (and answering the initial question, that might be a reason for deselecting the RMI's after landing!)

320p
25th Mar 2009, 16:02
Hello Penko,
Could I summarise by your replies that since the use of OFF position has not been mentioned at any place in the FCOM and FCTM ,its use would be purely based on individual pilot's technique,rather than a procedural or technical reason.:confused:
Thanks

PENKO
25th Mar 2009, 16:14
Well, my FCOM's SOP section is taken over and ammended by my airline, so I could not really comment on what goes on in other airlines. All I can say is that my version does not mention switching them off.

A330-343E
26th Mar 2009, 00:17
I was on a Qantas A332 a few months ago. I noticed the ADF selectors are now labelled as "DEACT". Why do they do that?

TyroPicard
26th Mar 2009, 10:31
PENKO
Well, my FCOM's SOP section is taken over and ammended by my airline, so I could not really comment on what goes on in other airlines. All I can say is that my version does not mention switching them off.

So why switch them off? I say again, how do you monitor flight progress in the cruise? The map is synthetic; a VOR is real.

What I meant is that by switching the pointers off after TO I subsequently have to make a conscious effort to switch them back on in the correct way during the approach. I will then have a fresh mental picture of what is pointing to where.

There is no "correct way" - every approach is different and you monitor VOR or ADF as required by the a/c position on the STAR or approach. And what if you forget to make that conscious effort due to tiredness?
Your "mental picture" should last the whole flight, not just departure and arrival.

toby320
26th Mar 2009, 16:14
well, there we go again, sops have a purpose so please don't invent procedures, in this case there is no mention about the way to use it in specific point or situation but once again common sense I mean use it in the way you need it but with out changing procedures.

well that my opinion:8

potkettleblack
26th Mar 2009, 19:53
I was on a Qantas A332 a few months ago. I noticed the ADF selectors are now labelled as "DEACT". Why do they do that?


Possibly they removed the ADF's from the aircraft or were never shipped with them in the first place. Will depend on what the OZ CAA's requirements are for carrying them. With GPS now ADF's are dying off. Just an additional cost to maintain and certify but add little these days. On an airbus we can do a fully managed non precision approach using the GPS in much the same way as you would an ILS to a much higher degree of accuracy than if we were doing it raw data trying to follow an ADF needle.

Posh boy
26th Mar 2009, 21:18
fully managed non precision approaches especially ndb are not recommended and you can certainly do better selected as opposed fully managed ndb.
In certain cases such as two ndb you might find yourself way too low as bus will not follow vertical profile, have seen it and I wouldn's say it is safe.

PENKO
26th Mar 2009, 23:49
TyroPicard, according to 'the books' we can use the VOR/ADF pointers as we deem necessary. In the cruise, with GPS-primary and all that goes with it, are you not happy to consider those 24 satelites as real as a random VOR? My SOP's do, based on Airbus.

Posh boy
27th Mar 2009, 08:28
What TyroP is saying you can not navigate based only on the map. It is not approved for this purpose at all. Have you heard of the map shift, it used to happen a lot in early days of bus now unlikely due gps. However try to position yourself onto final using your map on a flight check and any self respecting checker will fail you ( in my airline anyway) or make a deal out of it. As for cruise my sop's say both to vor , as it inhances situational. Relaying on gps and a map will live you in a pot when a big bang happens. Ask youself a question why is it you set all those needels for departure and arrival if "you could do it on the map"?

Regards

PB

PENKO
27th Mar 2009, 08:55
First of all, yes you can, under the strict conditions for instance of the GPS approach. Subject to your CAA and airlines approval of course. However, since I am as hesitant as anyone else to the idea to fly down to minima based on GPS alone I will not use that argument.
edit And of course, the database has to be scrutinized and validated by the airline and the pilots, the GPS constellation has to be check for every approach, you need 2 GPS receivers, two FMGC's etc. etc., all things that don't apply on a standard flight that we are discussing, where there is an absolute need to monitor raw data under the circumstances already mentioned.

Please read what I have been writing. In the cruise, above MSA, there is no need to monitor raw data as long as you have GPS primary. That is what Airbus says. That is what my company says. That is what I follow. Below MSA is a different story, albeit no so different according to paragraph 1.

Regards, you will never see me free-tuning during departure! :ok:

goeasy
27th Mar 2009, 09:05
Penko, I agree with you, but to have the VOR needles showing, gives you a big clue about map shift, even if the 'GPS primary lost' isnt annunciated. In my new airline the SOP is to check prog page passing 10000ft to check it is still GPS primary/Acc Hi. What a waste of time! You either trust your systems, or turn them all off I believe.

And on a parallell matter our SOP is to tun off both FD after landing. Why? Just increases chances of departing again without. Certainly not an Airbus recommendation, as far as I (or my previous airline) know. Anyone else got ideas? :8

PENKO
27th Mar 2009, 10:09
I added some text to my previous post for clarity.

Lemurian
27th Mar 2009, 14:57
The original question :
The VOR/ADF selector on the FCU also has OFF position .I have noticed some pilots after landing select the OFF postion,though it is nowhere mentioned in the FCOM.
It's a matter of SOPs : It's better to leave that selection to the next pilot for his departure. Leaving them may in fact lead to confusion as to who made the selection and whether the selection matches the departure requirements.
The pre-departure briefing should cover that aspect of the navigation aids.


And on a parallell matter our SOP is to tun off both FD after landing. Why? Just increases chances of departing again without. Certainly not an Airbus recommendation, as far as I (or my previous airline) know. Anyone else got ideas?
Leaving switches in position doesn't guarantee that you'd get what you'd look for, in this case 1FD2 after a new power-up.
The cockpit verification check-list covers that item and forces you to confirm that both FDs are getting their source from their own system.

toby320
28th Mar 2009, 01:50
departing with out fd's because you turned off after landing?? no way, follow your sops when both pilots seated you check fd's on :=

Dream Land
28th Mar 2009, 02:50
DDRMI deactivated has to do with a previous problem associated with an IRS 3 issue, ours have been modified and usable. I switch to the middle position as a courtesy to the next crew, sort of like pushing the rudder pedals forward, nothing in the FCOM about that either. :rolleyes: