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UA A320 at DEN: "Total Hydraulic Failure"?

thepotato232

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http://www.denverpost.com/breakingnews/ci_13609730?source=rss

In short, the report says that UA418 landed safely on 34L at DEN with a total hydraulic failure. As in NO control surfaces.

Has anyone here heard anything about this? The story has received virtually no attention, suggesting either the media is incorrect either about the extent to which the airplane was crippled, or simply has no idea what a "total hydraulic failure" generally means for the folks trying to fly the airplane.

As I understand it, an A320 that's lost all three hydraulic systems has no control whatsoever other than differential thrust, ala UA232. "Mechanical Backup", the mode to which the plane reverts in the event of a complete electrical failure, simply allows for the manual adjustment of the hydraulic valve of one of the trim tabs.

*Update: Just heard from a family friend with the FAA - so far, the official line from them is "Landed with total hydraulic failure."
 

MCDU

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I bet they had blue hydraulics supplied by the RAT. Worse case they were in direct law. I hardly believe they landed in mechanical backup.

M
 

thepotato232

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The story so far says "total hydraulic failure," including Blue. The RAT and direct law/mech. backup only apply when you've lost electrical...
 

thepotato232

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Agreed - that's why I was hoping somebody here had heard something. So far, everyone from the news outlets to the (anecdotal) word from the Fed is saying the same thing.
 

N1atEcon

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Where is Falcon (ballon boy) and his Dad? Great time to get some exposure.
 

eaglesview

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The story so far says "total hydraulic failure," including Blue. The RAT and direct law/mech. backup only apply when you've lost electrical...

As a guy with 5 years on the airplane I assure you that is a completley inaccurate statement.
 

thepotato232

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Ah, sounds like they most likely lost Green, requiring the tow to the gate. Thanks for clearing that up.
 

B-atch

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Total hydraulic failure on the A320 = certain death...
Not even mechanical back up will save you'r a$$..
 

thepotato232

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Any reason they couldn't try the ol' differential thrust trick? Something to do with Pierre not letting them move the thrust levers?
 

Ralph Cramden

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Any reason they couldn't try the ol' differential thrust trick? Something to do with Pierre not letting them move the thrust levers?

It's Fifi, not Pierre. :p And yes, you can move the thrust levers all you want. The thrust levers actually controlling the thrust is the big maybe. The non moving thrust levers is my biggest complaint about driving the bus.
 

Redtailer

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Looks like a case of media run amuck again.

United spokeswoman Sarah Massier, however, said the plane experienced only minor problems and did not have to be towed after it landed.

Not saying that the spokeswoman was accurate, but if it's true that the plane taxied to the gate and didn't need a tow doesn't that imply that at least 1 hydraulic system was working? Also, if you lost complete hydraulics, landed, and still decided to taxi to the gate wouldn't you at least get the gear pinned first????

Just a thought...
 

ableone

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As a guy with 5 years on the airplane I assure you that is a completley inaccurate statement.

Then you need to go back to the books.

The rat will drive the blue circuit (assuming it has fluid and is operable) but with no hydraulics the only control available is the engines.

Airbus "mechanical backup" means using the hydraulically operated rudder pedals (any one of the three hydraulic systems) and the hydraulically operated THS (operated by the green or yellow circuit).
 

MCDU

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During Mechanical Backup both the stab and rudder use cables going to a controller (mech. link) and require hydraulic power. Plane is not designed to be flown during longer periods of time in mechanical backup. No hydraulic fluid left means the airplane is a lawn dart.

M
 

eaglesview

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Then you need to go back to the books.

The rat will drive the blue circuit (assuming it has fluid and is operable) but with no hydraulics the only control available is the engines.

Airbus "mechanical backup" means using the hydraulically operated rudder pedals (any one of the three hydraulic systems) and the hydraulically operated THS (operated by the green or yellow circuit).

Try reading the post I was quoting and then come back with with a post that makes sense.
 

GuppyWN

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If it was a Boeing you'd do something fancy like........... just fly the damn thing!

Gup
 

ableone

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During Mechanical Backup both the stab and rudder use cables going to a controller (mech. link) and require hydraulic power. Plane is not designed to be flown during longer periods of time in mechanical backup. No hydraulic fluid left means the airplane is a lawn dart.

M

Always a one day delay for you to go and ask dad how the airplane works.

The plane is designed to be flown for extended periods of time in mechanical backup and to be landed in this mode.

As part of training every AWA pilot has performed at least one landing in mechanical backup.
 
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MCDU

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Always a one day delay for you to go and ask dad how the airplane works.

The plane is designed to be flown for extended periods of time in mechanical backup and to be landed in this mode.

As part of training every AWA pilot has performed at least one landing in mechanical backup.


wrong rookie. Is possible to fly it for extended periods of time or can it be landed? Yes. But Airbus intended mechanical backup to be a temp. situation. It is almost impossible to fly an instrument approach. You better have a long and wide rwy and vfr.


M
 
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ableone

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wrong rookie.

M

I must have been hallucinating when I watched the test pilots land the airplane in mechanical backup as part of its original certification program.

Further I guess I was dreaming when I landed the airplane with the trim wheel and pedals as part of my original training.

Further I must have also hallucinated the mechanical backup landings that my sim partner and I performed when I returned to the airplane several years ago.
 
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