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Is the 787 a failure ?



 
 
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  #21  
Old January 26th 13, 02:00 PM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
Jim Wilkins[_2_]
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Posts: 52
Default Is the 787 a failure ?

"Daryl" wrote in message
...

It sounds like they are being overcharged. That is prevented by a
simple card addition that prevents it on only of overcharging but
undercharging. Easy fix.

Daryl


The Lithium medical and electric vehicle packs I worked on were
controlled by ICs that monitored and recorded individual cell voltage
and overall charge and discharge current. Those are point measurements
that are easy to do. What's harder is detecting unexpected hot spots
away from the temperature sensors. Minor differences (improvements)
between the acceptance sample and production devices can change heat
flow paths.
http://www.mpoweruk.com/lithium_failures.htm



  #22  
Old January 26th 13, 02:18 PM posted to rec.aviation.piloting,rec.aviation.military
Keith W[_4_]
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Posts: 39
Default Is the 787 a failure ?

Vaughn wrote:
On 1/25/2013 6:17 PM, Transition Zone wrote:
The last time a plane was grounded was what? 1979? That's a big
deal. I remember the A320 had an early scuff-up when it started out,


The A300 was certainly a candidate for grounding after one lost a
vertical stabilizer in 2001 for no apparent reason. Vital parts
failing, falling off, and causing a plane crash with 100% fatalities
sounds a whole lot more difficult to fix that the 787's electrical
problem.


The fact that the NTSB enquiry showed that the fust officer had
overstressed the stabilizer by aggressive alternate full rudder
inputs at a relatively high airspeed was a pretty good candidate
for an 'apparent reason' as was the fact that the A300 had flown
into the wake turbulence of a JAL 747-400

Bottom line is that the pilot overstressed the airframe as
his use of alternate full rudder inputs resulted in large
angle of sideslip which tore off the stabilizer. The loads
imposed by the sideslip were more than double the design
limits.

The FAA airframe engineer stated that for any aircraft

" a maneuver with alternating rudder inputs was an extreme maneuver
and that, if the maneuver were performed, loads would build that
would exceed the current requirements. He further stated that, if two
sets of alternating rudder inputs were performed, a series of
dynamic maneuvers would start that could lead the airplane into
a severe dynamic situation where, at the proper frequency, this continued
application of this surface would allow the motion of the
airplane to build up to the point where the sideslip would become
excessive and overload the airplane "

The flight data recorder and CVR showed exactly such a sequence of
rudder inputs was made.

Keith


  #23  
Old January 26th 13, 02:46 PM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
Daryl
external usenet poster
 
Posts: 36
Default Is the 787 a failure ?

On 1/26/2013 6:00 AM, Jim Wilkins wrote:
"Daryl" wrote in message
...

It sounds like they are being overcharged. That is prevented by a
simple card addition that prevents it on only of overcharging but
undercharging. Easy fix.

Daryl


The Lithium medical and electric vehicle packs I worked on were
controlled by ICs that monitored and recorded individual cell voltage
and overall charge and discharge current. Those are point measurements
that are easy to do. What's harder is detecting unexpected hot spots
away from the temperature sensors. Minor differences (improvements)
between the acceptance sample and production devices can change heat
flow paths.
http://www.mpoweruk.com/lithium_failures.htm




I can see a problem that is being addressed in Electric Vehicles.
Heat and cold.

On an electric vehicle, getting the battery too cold will (not
can) result in a degrading of the performance of the cells. The
fix is adding an "Electric Blanket" to keep the battery warm (not
hot). The residual power required by the blanket is negligible.
You get back much more than you lose.

Heat. I can see problems with the Lipo batteries. The battery
they chose is one that is not on the list of Vehicle safe
batteries. It is the best, the highest output but with it comes
problems. Lithium cobalt oxide (LCO), for vehicles, is listed as
unstable compared to the rest. It's very suspeptable to heat.
And sitting on the ground running up on a hot day, the battery
compartment will sky rocket in heat. The safest to use is the
lead acid but it's very short lived in this application. To use
any Lipo battery, it requires a cooling and a heating system to
keep the battery at an optimal temperature. The LCO is just the
worst of the lot for overrunning (catching fire, generating
Oxygen when it burns) than any other Lipo battery.

The Fix? Get rid of the LCO and temperature control the battery
compartment. Even a Lead Acid doesn't like excessive cold or
heat. But it won't turn into a major oxygen fire. Sometimes,
newer isn't better. But the various other Lipo batteries are
safer than the LCO which has a proven track record of burning.

BTW, the LCO isn't the cheapest by far. The LipoMG battery is
the cheapest but it has a low service charge rate. The Lipo4 has
a decent service rate and is what is primarily used in various
vehicle applications. But, maybe, the old Lead Acids may be the
way to go on this one. They are the most stable and the most
safe if you keep them in a wide range of temperatures.

Newer isn't always better.

Daryl



--
http://tvmoviesforfree.com
for free movies and Nostalgic TV. Tons of Military shows and
programs.
  #24  
Old January 26th 13, 04:08 PM posted to rec.aviation.piloting,rec.aviation.military
Vaughn
external usenet poster
 
Posts: 154
Default Is the 787 a failure ?

On 1/26/2013 8:18 AM, Keith W wrote:
Bottom line is that the pilot overstressed the airframe as
his use of alternate full rudder inputs resulted in large
angle of sideslip which tore off the stabilizer. The loads
imposed by the sideslip were more than double the design
limits.


None of which excuses the design. Pilots are taught from day one that
full deflection of flight controls is generally permissible below a
certain magic "maneuvering speed" without causing harm to the airframe.
Given that the accident flight was in the climb phase, that plane was
almost certainly below that speed.

So this turned out to be a flight limitation that the pilots hadn't been
told about and was nowhere in the flight manual. This DESIGN DEFECT was
"fixed" by changing the flight manual to add new flight limitations and
retraining pilots. To be fair, I know of no other similar accidents
since then.

Going back to my central point, the A300 easily survived that negative
publicity, as will the 787.
  #25  
Old January 26th 13, 04:59 PM posted to rec.aviation.piloting,rec.aviation.military
Keith Willshaw[_3_]
external usenet poster
 
Posts: 49
Default Is the 787 a failure ?

Vaughn wrote:
On 1/26/2013 8:18 AM, Keith W wrote:
Bottom line is that the pilot overstressed the airframe as
his use of alternate full rudder inputs resulted in large
angle of sideslip which tore off the stabilizer. The loads
imposed by the sideslip were more than double the design
limits.


None of which excuses the design. Pilots are taught from day one that
full deflection of flight controls is generally permissible below a
certain magic "maneuvering speed" without causing harm to the
airframe. Given that the accident flight was in the climb phase,
that plane was almost certainly below that speed.


Trouble it was at that speed which at the altitude in
question was 250 knots. When the stabilizer failed the
speed was at 251 knots and the pilot had applied full power

So this turned out to be a flight limitation that the pilots hadn't
been told about and was nowhere in the flight manual.


True to an extent but the issue was not in an Airbus flight manual
but in an FAA document ( Title 14 CFR 25.1583, "Operating Limitations")

This stated that

Quote
that full application of rudder and aileron controls, as
well as maneuvers that involve angles of attack near
the stall, should be confined to speeds below this value."
Quote

This was found to be ambiguous in that it implied that multiple
full deflection inputs were safe at or below the safety speed.
This the NTSB and FAA found was not true for most large
transport aircraft and the FAA document was amended to
inform operators that operating at or below maneuvering speed
does NOT provide structural protection against multiple full control
inputs in one axis or full control inputs in more than one axis at the
same time

After the accident Boeing issued the following clarification to its users.

"Boeing aircraft are not designed to a requirement of full authority
rudder reversals from an "over yaw" condition. Sequential full
or nearly full authority rudder reversals may not be within the
structural design limits of the aircraft, even if the airspeed is
below the design manoeuvring speed. "


The AA flight training centre was using faulty
simulator training that encouraged the use multiple
cyclic full rudder inputs to control wake roll
problems and had fostered the mistaken belief that
the rudder limiter would prevent any bad results from
excessive inputs.

The extent of the forces caused by the rudder inputs may be
gauged from the fact that the flight data recorder showed
they caused alternate lateral accelerations of between
0.3 and 0.4 G

This DESIGN
DEFECT was "fixed" by changing the flight manual to add new flight
limitations and retraining pilots. To be fair, I know of no other
similar accidents since then.

Going back to my central point, the A300 easily survived that negative
publicity, as will the 787.


I am sure that it will, battery and charging system problems
should be easy to resolve.

Keith


  #26  
Old January 26th 13, 05:28 PM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
Michael A. Terrell
external usenet poster
 
Posts: 26
Default Is the 787 a failure ?


"Mr.B1ack" wrote:

On Fri, 25 Jan 2013 22:21:55 -0600, F. George McDuffee wrote:

When you want it really really bad, that's generally how you get it...
-----------------------

On Fri, 25 Jan 2013 20:54:55 -0600, "Mr.B1ack" wrote:

snip
Now from a business point of view however ...

snip

These URLs may be of interest. If an emergency is defined as an event
that was unanticipated in occupance and limited in duration, clearly
this is no emergency.


That's TECHNICAL ... "legal" ... has NOTHING to do
with how potential passengers should act or react.

Passengers are convinced the 787 is a death-trap.
That's ALL it takes to destroy it.



All planes are death traps. You can't pull over to a cloud & call for
a tow, for any of them.
  #27  
Old January 26th 13, 09:23 PM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
Transition Zone
external usenet poster
 
Posts: 18
Default Is the 787 a failure ?

On Jan 25, 9:00*pm, Too_Many_Tools wrote:
On Jan 10, 2:02*pm, Transition Zone wrote:









Date: Thu, 23 Dec 2010 21:23:55 -0500
Local: Thurs, Dec 23 2010 9:23 pm


JF Mezei wrote:


On December 23rd, Boeing announced it is now resuming flight testing on
ZA004.
They have updated the power distrubution *software* and will test this,
along with deployment of RAT before resuming normal testing for
certification.
So it appears that the hammer that was left in some electrical cabinet
probably highlighted some software problems. Thankfully, updating
software is less tedious than having to dismantly, change a part and
reassemble the number of 787s already built.


A Week Boeing Would Like To Forget
By Alex Zolbert, CNN, updated 2:01 PM EST, Thu January 10, 2013


More concerns for Dreamliner - (CNN) -- Some passengers pay no
attention to what type of airplane they'll be flying on. Others are
obsessed.
I'd put myself in the middle of the pack, mainly due to the new planes
on offer from Airbus and Boeing.
So I was in slightly better spirits this week, as I boarded the 11-
hour United Airlines flight from Los Angeles to Tokyo this week.
It was my first chance to fly on a Boeing 787 Dreamliner.
But the trip quickly descended into -- certainly not a nightmare --
but definitely a headache.
Dreamliner catches fire at airport


It's a drill millions of travelers know all too well.
After starting the taxi out to the runway Monday morning, we were
informed that there was an issue with the computer system, and they
were unable to start one of the plane's engines. We remained onboard
for nearly 3 hours, as flight attendants sheepishly offered cups of
water to frustrated passengers.
Eventually we disembarked.
A delay of four hours turned into five, then six, seven ... and the
flight was eventually canceled.
We then had the pleasure of spending the night at an airport hotel
that seemed to have been last updated around the time commercial air
travel started.
It was then that I realized we weren't the only ones encountering
issues with the Dreamliner on Monday.
A Japan Airlines' 787 caught fire in Boston after passengers
disembarked.


Boeing said the fire was traced to a battery unit that helps to power
electrical systems when the engines are idle -- typically while a
plane is being serviced or cleaned. And the company says it's
cooperating with investigators.
As Tuesday morning arrived, we were back on board another United
Airlines' Dreamliner in Los Angeles.
But in a rather comical turn of events, the second plane never left
the gate.
We were told there was an issue with the paperwork filed with the FAA.
More than a day late, many coffees, and very little sleep later, the
third time finally proved to be the charm -- more than 24 hours after
our scheduled departure.
But as we finally took to the skies, more Dreamliner issues were
unfolding.
Another Japan Airlines' 787 in Boston had to scrap a takeoff on
Tuesday due to a fuel leak. And an ANA Dreamliner flight was canceled
in Japan on Wednesday, because of a glitch with its brake system.
But Boeing is standing by its latest aircraft. The company's chief
project engineer, Mike Sinnett, says he is "100% convinced the
airplane is safe to fly."


Analysts seem not to be alarmed, saying that new aircraft models often
have "growing pains."
But what is very clear is this was a week that Boeing would certainly
like to forget.
After a nearly 40-hour trip back home, I'll second that.


--http://www.cnn.com/2013/01/10/business/dreamliner-los-angeles/


BIG problem.

The batteries are obviously being overcharged..a system problem.

To fix the problem and have the recertifications will take time..and
BIG dollars until the plane files again.

I suspect it is a failure to properly oversee system integration
within Boeing.

And where there is smoke there is fire...if the electrical system has
not been properly reviewed it is a KEY signal that there are other
similar oversights.

Bottom line..if I were actively flying I would NOT fly the 787 for
years...let someone else be the lab rat.


Other planes have made bad splashes into the market or service and
later fared better. Here, I think the battery system was being
strained; i.e. being used without a diesel (jet fuel) powered main
power unit, which all planes on the ground need. Probably human error.
  #28  
Old January 26th 13, 09:30 PM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
Transition Zone
external usenet poster
 
Posts: 18
Default Is the 787 a failure ?

On Jan 25, 9:54*pm, "Mr.B1ack" wrote:
Strictly speaking, the 787 is not an engineering failure.
Like anything complex and new it has a few issues. So far
these issues haven't caused any fatalities.


But, the then-new EU Airbus airliner (A320) did have mostly fatalities
on an opening day mess-up, back on June 26, 1988, at Mulhouse-Habsheim
Airport. Airbus's A380 had terrible delays, too.

In a year or two, offer a "797" ...


Beoing's 787 didn't have any fatalities. So, I'd say stick with the
current program. (especially, if Airbus weathered and overcame their
mistakes)
  #29  
Old January 26th 13, 09:33 PM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
Transition Zone
external usenet poster
 
Posts: 18
Default Is the 787 a failure ?

On Jan 26, 11:28*am, "Michael A. Terrell"
wrote:
"Mr.B1ack" wrote:

On Fri, 25 Jan 2013 22:21:55 -0600, F. George McDuffee wrote:


When you want it really really bad, that's generally how you get it....
-----------------------


On Fri, 25 Jan 2013 20:54:55 -0600, "Mr.B1ack" wrote:


snip
Now from a business point of view however ...
snip


These URLs may be of interest. *If an emergency is defined as an event
that was unanticipated in occupance and limited in duration, clearly
this is no emergency.


* *That's TECHNICAL ... "legal" ... has NOTHING to do
* *with how potential passengers should act or react.


* *Passengers are convinced the 787 is a death-trap.
* *That's ALL it takes to destroy it.


* *All planes are death traps.


No, this isn't the 1930's anymore.

You can't pull over to a cloud & call for a tow, for any of them.


Since then, you hardly ever have crashes because of all-weather
designs, flight patterns and glide paths (in case you need to land).

  #30  
Old January 27th 13, 02:56 AM posted to rec.aviation.piloting,rec.crafts.metalworking,rec.aviation.military,talk.politics.misc,alt.society.labor-unions
[email protected]
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Posts: 155
Default Is the 787 a failure ?

On Sat, 26 Jan 2013 01:42:01 -0600, "Mr.B1ack"
wrote:

On Fri, 25 Jan 2013 22:21:55 -0600, F. George McDuffee wrote:

When you want it really really bad, that's generally how you get it...
-----------------------

On Fri, 25 Jan 2013 20:54:55 -0600, "Mr.B1ack" wrote:

snip
Now from a business point of view however ...

snip

These URLs may be of interest. If an emergency is defined as an event
that was unanticipated in occupance and limited in duration, clearly
this is no emergency.


That's TECHNICAL ... "legal" ... has NOTHING to do
with how potential passengers should act or react.

Passengers are convinced the 787 is a death-trap.
That's ALL it takes to destroy it.


You are convinced passengers are convinced. There have been no deaths,
no injuries, and only limitted damage to this point. A minor tweek
will likely solve the battery problem. It appears to be a problem with
the APU not knowing how to handle Lithium batteries, as the problem
occurs when on the ground with the APU running the system.
 




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