AC602, mechanical failure of the floor
 

They boarded us on AC602 this morning, an A320. One of the crew reported to the captain that the floor in the back cabin didn't 'feel' right.

The brought on their Sheet Metal Specialist to have a look, then de-planed us all because they had to pull the carpet back. Sure enough, within a few minutes of de-planing, they deemed the a/c un-serviceable due to the floor.

How often does this or can this happen? What's happening to sheet metal under the floor that they wouldn't catch in their regular check-ups?

It's the last thing I would have expected for a mechanical failure.

I wonder if they are extra sensitive to metal-related things due to the SW issues, even though the floor wouldn't seem to have much to do with what happened to the SW aircraft.

I've never heard of an mx issue relating to a floor before either.

I know some models of aircraft (IIRC, B757/B767) are susceptible to corrosion in those areas because of leaking toilets and galley fluids.

isnt their interior floor made of fiberglass, wood panels or composite? i know its used in the flooring of other forms of transportation and over time they do rot

I was on this flight as well and the captain can be quoted as saying "...one of the crew says that the floor doesn't feel good." My immediate thought was to ask if we could offer it some tylenol and a hug and get on our way. Like the OP said, it only took about 15 minutes after deplaning was completed for the announcement of "The aircraft is unserviceable" to be made.

Total delay was 1hr 45min which isn't so bad considering the effort to move passengers, crew, baggage and catering. The only thing that stood out to me in the whole process was the revised departure time on the display. Overly optimistic is probably the best way to describe it. For example, it said 8:40 when, at 8:10, the inbound replacement plane was still deplaning. It was obvious to me that there was no way we were making that time. I overheard many conversations where people were re-assuring their rides/family/etc that they would be leaving at 8:40 and arriving by 11:40 or actually making connections in Halifax. By no means am I suggesting that AC should have pushed to get us out by 8:40, but being more realistic with the departure time would have saved their customers from a number of cascading, non-AC controlled, scheduling failures.

Overly optimistic scheduled times when delays are obvious seem to be a normal feature of air travel, and I agree that it creates unnecessary hopes. Check the inbound arrival time for any delayed flight and you will see an impossible turnaround for the aircraft.

Just as you could immediately tell that your rescheduled flight was never going to leave as shown, it surely can't be too difficult for the people actually running the airline to figure it out!

(Having said that, I did recently have the unusual experience of a posted delay being reduced, but that was SFO weather unexpectedly improving, a situation I am willing to acknowledge AC had no control over!)

Wood?!

Must be thinking of http://en.wikipedia.org/wiki/De_Havilland_Mosquito :D

Floor panels are a carbon fiber honeycomb, but are load limited and susceptible to damage from stilettos and other sharp items which weaken them over time.

Ramp Roscoe
YVR

Just like a Boeing 787? :D

No - these are sandwich panels with a honeycomb core, much like a ski. They are very stiff, but not very resistant to sharp local loads as the skins can perforate easily. Also, because of the thin skins on the panels, they are susceptible to fluid ingression into the core which can then lead to delamination and core degradation etc.,...

B787 (and A350) are in the largest part made of monolithic (solid) carbon fibre/epoxy laminate structures, which can take local loads/failures much better, and certainly in fatigue (cf Southwest 737 skin failure this week). On the external structure there will be some sandwich panel structures (e.g. main landing gear doors, rudder, etc.,) but none are primary structure (cf rudder coming off Air Transat Airbus a few years ago).

I would guess that the floor panel failing is not a flight critical issue, but kudos to AC for taking the plane out of service when discovered on the ground.

As I recall, in the case of Turkish DC-10 that crashed in France, because of cargo doors not properly locked even though the unlocked doors indicators in the cockpit showed them locked, floor did play a role.

When the cargo door fell off, the cargo compartment lost pressurization and the pressure ended up applied on the floor, because venting was not sufficient, and the floor collapsed.

(On second thought not sure if that happened in the Turkish case, or in another DC-10 cargo door incident, a US-registered plane, over Canada -possibly Windsor. Which however survived and landed somewhere.)

it reminds me of the 30 rock episode explaining why they do 30-minute delays. It had me loling when i saw it.

I vaguely remember something similar, but the issues are quite different as you might agree. My point is that a damaged floor as described in this thread is most likely not a flight critical issue if discovered in flight. It is a maintenance issue on landing. What you are talking about is the inability of the floor to take unanticipated differential pressure loads due to cargo area depressurization and insufficiently fast venting of the passenger area pressure...

Correct. In that instance, the floor broke and some rows of seats + occupants went through the hole.