A320 status showing in op systems without prior ECAM caution
 

Occasionally on MSN >6000 we get an ECAM status page showing
CAT3 SINGLE ONLY with CAT3 DUAL listed under inoperative systems, this without any kind of ECAM warning or caution. Only in the air. Anyone shed some light as to why this might be happening and how, technical speaking, Airbus pilots must treat this when determining landing requirements for an LVO approach?

Going back to some of the early three digit msn A320F it was due to an ADR disagree.
The next time it happens look at the cfds and select current leg report.
If the aircraft has decided you are Cat3 single then that is what you will get.
See also:
http://www.pprune.org/tech-log/56293...y-no-ecam.html

This can happen on the ground also. On the ground, if you hard tune an ILS in the Rad Nav page then clear the ILS it removes the status. I can't remember why this works, it was explained to me one day but I can't recall the logic!

If the aircraft says Cat 3 single then plan for Cat 3 A approach. The reason you don't get an ECAM caution is because there's no associated ECAM message or actions for the specific failure - as others have said it is often down to an ADR disagree, and one of the reasons we review the status page before starting an approach.

CFDS will give you a rough idea in flight if you're curious with more detailed reporting on the ground.

This happens on ground as well....Park brakes on...Press brake peddals..Check status...cat 3 single only

Now then that's an interesting one. I wonder why it does that as the brake pedals don't do anything when the park brake is applied?

I had one the other day
NAV LS tuning disagree. A disagree between MMR1 and MMR2 which is a joint GPS/ILS box.
On the ground we had no caution but inop CAT 2 (interesting one as you can't arm the approach pb).
The caution came up at 1500 feet, once out of TO inhibit.
Easy way to solve it is to hard tune the ILS in the rad nav page.

This one actually goes away by itself when you're preparing the approach and select the runway for arrival. At least that's how it's happened to me the 2 or 3 times I've got it.

You prepare for a Cat 3 approach with DH.

Our manuals only allow CFDS on the ground with both engines off and the park brake set.

As previously mentioned, it happens usually when ADRs disagree. I have been showed a trick which worked in flight ( don't know the technicalities behind it though ) : engage AP 2, reset FAC 1, then engage AP1, reset FAC 2. That can rid you of the CAT 3 SINGLE ONLY on the memo. Of course it goes without saying that if you have CAT 3 SINGLE ONLY memo, you will of course be able to shoot a CAT 3 SINGLE ONLY approach.
Happy landings.

Anyone able to expand on what speedbird said regarding pressing the brake pedals and CAT 3 single.
Not noticed this myself, can't say I've tried.

Tricks and Airbusses....bad idea! Especially if you 'don't know the technicalities'...

This is a VERY bad idea. Read the final report of the Air Asia crash and hopefully you will see it yourself as well.

Doing some random non-approved resets in flight on a very complex and computer-driven aircraft. What could possibly go wrong....

I'd avoid resetting a flight control computer (ELAC, SEC, FAC) unless requested by ECAM/QRH at all costs. Especially in flight!

WHEN you reported this fault after arrival, in the tech log not on a scrap of paper pinned to the table, what did the engineer/mechanic sign it off with? There should be a TSM/AMM reference for the fix.

Or am I missing something?

QRH gives green light to computer resets in flight, with the caveat that you do it one at a time...

There's also a difference between pulling the CB for a computer (bad idea) and using the push button control.

Yes that's right, but that's in the event of a failure, not just randomly resetting computers and autopilots for the sake of it.

Exactly. We operate SOP. We are pilots not engineers. We use the Airbus approved manual to operate the aircraft safely, we don't write nor rewrite, nor selectively quibble the clear meaning of the manual.

"The PIC had seen the engineer resetting the FAC CB on the ground. Having experience of witnessing and performing FAC CB reset, the PIC might consider that he “fully understand the consequences”. Resetting the FAC CB on the ground and in flight has different consequences. The FAC CBs were not included in the list of the CB allowed in OEB and TDUs to be reset in flight. The consequences of resetting FAC CBs in flight are not described in Airbus documents. It requires good understanding of the aircraft system to be aware of the consequences."

QZ8501. 162 dead.

Yes! just follow the procedures. Cockpit is not a place to allow creativity to run wild.