A340 Engine Test Gone Wrong

Bertie the Bunyip wrote in
:

Tina wrote in news:d0ba294f-7bbd-46a2-aac7-
:

Is there enough thrust during an engine test on an A340 to drag locked
gear?


You mean brakes? Yes, there is. You can take off with the parking brake
full on, especially on a wet runway, or so I've been told, anyway!
I haven't tried it myself.
Typically they only run up one at a time, of course.

I'm wondering if it's common to depend on blocks and the like to
restrain an airplane like this during a test, or does one commonly
engage the brakes as well?

They'd have to. It look like it might have been a brake failure that did
this. If the antiskid went into "test" for instance, or a shuttle valve
got stuck somewhere The airbus braking system is a bit strange and not
well thought out. I once had a brake failure on landing when the anti-
skid decided to do a test cycle. It wasn't a 340, but the system is
essentially the same.



I guess they'll just take the cost to repair out of someone's
paycheck.


Nah. unless they did something criminal, they should be OK It'l likely
be a combination of things that caused the accident, not a single item.
It depends on who was doing it as well. Engineering tend not to use
checklists since they actually know how the airplane works. However,
they don't think like pilots and tend to turn on only the bits they need
if they are going to start engines or taxi the airplane. It can leave
them a bit vulnerable. For instancde, they might decide they only need
to turn on the green system hydraulic since that will work the main
brakes and nosewheel steering. They don;'t need flight controls, after
all. but if that fails and the yellow sysem isn't right there to catch
it, they wouldn;'t have time to get them on before th eairplane hit
something.
Sabena crashed an A340 or 330 into another airplane of their own years
ago while it was on tow. The 'Bus hit one of Sabena's own 737s and wrote
it off. The next day, they also groundlooped a 340 in Brussels! Bad week
for them!

Bertie






Bertie - there was one report which said the A340 jumped the chocks as
well. Do you know how large in relation to the wheel the chocks are for
that aircraft?

The reason I ask is that earlier today I was at my FBO's bar-b-que
celebrating their second aniversary in their new building and spoke to the
head mechanic about it. He is an ex-Navy mechanic who said that on the
fighters he worked on, the chocks went up higher than the wheel hubs and
there was no way they were going to jump them unless they went to full
afterburner, and even then he sort of doubted it.

--
Marty Shapiro
Silicon Rallye Inc.

(remove SPAMNOT to email me)

Marty Shapiro wrote in
:

Bertie the Bunyip wrote in
:

Tina wrote in news:d0ba294f-7bbd-46a2-aac7-
:

Is there enough thrust during an engine test on an A340 to drag
locked gear?


You mean brakes? Yes, there is. You can take off with the parking
brake full on, especially on a wet runway, or so I've been told,
anyway! I haven't tried it myself.
Typically they only run up one at a time, of course.

I'm wondering if it's common to depend on blocks and the like to
restrain an airplane like this during a test, or does one commonly
engage the brakes as well?

They'd have to. It look like it might have been a brake failure that
did this. If the antiskid went into "test" for instance, or a shuttle
valve got stuck somewhere The airbus braking system is a bit strange
and not well thought out. I once had a brake failure on landing when
the anti- skid decided to do a test cycle. It wasn't a 340, but the
system is essentially the same.



I guess they'll just take the cost to repair out of someone's
paycheck.


Nah. unless they did something criminal, they should be OK It'l
likely be a combination of things that caused the accident, not a
single item. It depends on who was doing it as well. Engineering tend
not to use checklists since they actually know how the airplane
works. However, they don't think like pilots and tend to turn on only
the bits they need if they are going to start engines or taxi the
airplane. It can leave them a bit vulnerable. For instancde, they
might decide they only need to turn on the green system hydraulic
since that will work the main brakes and nosewheel steering. They
don;'t need flight controls, after all. but if that fails and the
yellow sysem isn't right there to catch it, they wouldn;'t have time
to get them on before th eairplane hit something.
Sabena crashed an A340 or 330 into another airplane of their own
years ago while it was on tow. The 'Bus hit one of Sabena's own 737s
and wrote it off. The next day, they also groundlooped a 340 in
Brussels! Bad week for them!

Bertie






Bertie - there was one report which said the A340 jumped the
chocks as
well. Do you know how large in relation to the wheel the chocks are
for that aircraft?

They're kind of scale to the ones used in light airplanes. They might
have been using even bigger ones than we use for parking for an engine
run though. Mercifully, I don't do engine runs and stuff like that much
these days so I can't say for certain.

The reason I ask is that earlier today I was at my FBO's
bar-b-que
celebrating their second aniversary in their new building and spoke to
the head mechanic about it. He is an ex-Navy mechanic who said that
on the fighters he worked on, the chocks went up higher than the wheel
hubs and there was no way they were going to jump them unless they
went to full afterburner, and even then he sort of doubted it.

I've never seen any that big for jet airliners, but they may well exist.
I doubt they were chocks only, but they may have been. Mosdt of the runs
I've done were unchocked. They were in the runup area though.
On DC-3s we had these giant steel tube frames that had a treadle on them
which changed the angle of the things slightly to wedge them tighter and
also to make it easier to get them out after you started. Ideally you
started with chocks set in those old airplanes because the preload you
put into the hydraulic system with the johnson bar manual pump often
bled away while you were starting. Similar sort of thing in modern jets,
except there are electric pumps while you are starting, but we noramlly
leave the nosewheel shocks in if we're starting on stand just for good
measure (as opposed to starting during pushback where the tug is the
insurance)
My guess would be that something in the flight deck wasn't in the right
position. If the brakes were set, then even at full power you wouldn't
get too far if oyu jumped the chocks. You should certainly be able to
stop the airplane just by closing the throttle if they were set.
However, never having lost one like that, I can't say for certain!


Bertie

"Phil" wrote in message
...
An Airbus A340 jumped its wheel chocks and broke the tie-down chains
during an engine test, then leaped forward and into a concrete
barrier. The entire nose section broke off. The crew was injured,
but thankfully no one was killed. Brand new airplane with exactly one
flight in the log. Now it's a write-off.

http://www.airliners.net/open.file/1293784/M/


http://www.avweb.com/newspics/airbus...t_02_large.jpg

Photo from the cockpit side of the wall!

On 2007-11-18, Bertie the Bunyip wrote:
Sabena crashed an A340 or 330 into another airplane of their own years
ago while it was on tow. The 'Bus hit one of Sabena's own 737s and wrote
it off. The next day, they also groundlooped a 340 in Brussels! Bad week
for them!

Perhaps that's why Sabena stands for Such A Bloody Experience Never
Again :-)

--
From the sunny Isle of Man.
Yes, the Reply-To email address is valid.

Dylan Smith wrote in
:

On 2007-11-18, Bertie the Bunyip wrote:
Sabena crashed an A340 or 330 into another airplane of their own
years ago while it was on tow. The 'Bus hit one of Sabena's own 737s
and wrote it off. The next day, they also groundlooped a 340 in
Brussels! Bad week for them!

Perhaps that's why Sabena stands for Such A Bloody Experience Never
Again :-)



He he. Neve heard that one!

Bertie

On Nov 17, 12:58 pm, Phil wrote:
An Airbus A340 jumped its wheel chocks and broke the tie-down chains
during an engine test, then leaped forward and into a concrete
barrier. The entire nose section broke off. The crew was injured,
but thankfully no one was killed. Brand new airplane with exactly one
flight in the log. Now it's a write-off.

http://www.airliners.net/open.file/1293784/M/

Didnlt look that bad, a lick of paint and she'll be good as new. g

Wil