Posted on 06/06/2009 5:29:56 PM PDT by george76
BRAZILIAN search aircraft late have spotted seats and part of a plane wing in the Atlantic where an Air France jet went down nearly a week ago, officials said after two bodies and other items were recovered from the area.
"Plane seats, part of the wing (and) various other items (were) localised,"
(Excerpt) Read more at theaustralian.news.com.au ...
Have they ruled out terrorism, yet? I really haven’t been keeping tabs on this...but am remembering how LONG it took for the doomed flight over Scotland to be tied to terrorism.
I’m surprised that some of Obama’s brethren haven’t claimed credit for this, true or not. ;-)
If it was terrorism, it could have been proof-of-concept for a bigger plot, in which case the organization wouldn’t claim credit.
I’m posing this question for the third time: Why don’t they encased the “black boxes” in some type of floatation device?
encased = encase
Flotation 'case' or not, it goes down with the plane, and stays attached, until someone disconnects it.
“Have they ruled out terrorism, yet? I really haven’t been keeping tabs on this...but am remembering how LONG it took for the doomed flight over Scotland to be tied to terrorism.”
I doubt they’ll admit to it being terrorism, but that is where my bets are.
Nothing ruled out as far as I know.
The flight data recorders are crash survivable. Therefore, the weigh a lot. Also, they must be secured to a rack or mount in the aircraft. Additionally, they have to be connected to sensors and computers through wire harnesses. How they are currently secured into the aircraft, if the area of said aircraft sinks, the recorders sink with them.
That is new technology, coming on board. We use it on our military aircraft. The industry has resisted due to the high cost and lack of product availablility.
Thanks. I knew someone would know. Perhaps a redesign is in order? Hopefully they will find these. May the passengers and crew R.I.P.
Post 10 gives more detail.
Post 11 answers your question.
Thanks to both of those posters.
Why don’t they make the plane out of black box material?
My theory is that the speed measuring pitot tubes iced over and auto pilot increased the engine power. Turbulence from the storm cell caused buffeting that overloaded the trim stabilizers and the aircraft lost control. Autopilot switched off by by then the aircraft was in a steep dive, exceeded airframe limits and broke apart.
A new type of control system on board does not allow pilots to over-steer. However when that system is not getting accurate data it can also keep pilots from obtaining control in a spiraling dive.
One of the hazards of fly-by-wire, computers are not good at emergencies. When unusual events layer on one another....the computers may not have a competent software response. How do you program human intuition and doubt? Those are essential for emergency decisions.
Experienced pilots have hunches and a feel for flying that cannot be replaced by computers. But then computers are cheaper, don't unionize, and allow lesser trained and cheaper pilots to be hired.
someone would have taken credit for it if it was a terrorist attack, wouldn't they?
Because if they did, it wouldn't get off the ground! (Yes, I know you're just making a joke.)
What about the French subs? Why do we have to do it?
Because if you want it done right, you have to do it yourself.
It's like the Canadian National Anthem ... O Canada, we stand on guard for thee!
Why would it be necessary for the sensor pitot tubes to ice over? The navigation computer apparently uses three sets of tubes to monitor velocity components in three dimensional space. Lets assume horizontal flight during which the plane flies into a "micro burst" of several hundred mph downward. Would not that appear to the "Z" axis sensor as a rapid climb which would cause the autopilot to go hard over into a dive, just exactly the wrong thing to do in a severe downdraft? I can not figure out how the system can differentiate between a speed signal generated by motion of the plane and one generated by the wind alone. Nor can I understand why they are not using inertial guidance which has no external sensors to confuse the issue.
Maybe I'm not seeing something obvious here, but it seems to me that a three axis system based on pitot tubes is almost certain to get bogus signals from external wind forces and icing can only make matters worse.
Regards,
GtG
The airlines refuse to make all their aircraft bright orange.
Retrofit costs or technology costs? Or bot
Prayers for the families.
Then they'd have to search for the entire plane. (Yes, I know it's a joke.)
They normally make sounds underwater so they can be found.
I do wonder though if they can take the likely water pressures involved. Anything with voids or that is compressible will be utterly crushed at that depth.
“What about the French subs? Why do we have to do it? “
You know the answer. Because no one else can get it done.
One theory holds that in this very tall 50k' storm, there may have been a hail "nursery" that they flew into. In theory, all the pitot tubes from one side could have been damaged or blocked but not the other side.
Airspeed is critical for control at that altitude and on that Airbus, cannot exceed .8 mach. If auto pilot erroneously increased air speed, the plane would quicky stall and then spiral dive.
Late at night, one pilot asleep, computer dampening any needed correction, a layering of faults. That is the key in accident investigation, unforseen layering of problems.
Pilots are warned not to believe disagreeing speed indicators but switch over to their backup GPS speed indicators. If that wasn't done, and pilots increased speed manually by mistake, a nose up stall.
When to believe and not believe instruments is the critical judgement of pilots and the cause of most accidents. Flying at night, autopilot, no visual references, sleepy tired.....pilot error.
One issue I have with fly-by-wire is that there is no "push-back" from the throttle levers, no tactile sense of turbulence or engine strain.
You are correct about the inertial guidance and GPS back up systems, they are available....if the pilots use and believe them.
If it is as deep as they say, the batteries and electronics may have been crushed by the extreme pressures at that depth.
Retrofit costs. The airframe has to have a hole cut in it for an ejection port, very spendy.
The idea is that the “black boxes” are supposed to stay attached to the aircraft; not go drifting off into the sunset.
But as we all learned in school, correlation does not imply causation.
Our hydrophones are much more sensitive. At 500 foot depth, we can tell how hard it is raining on the surface by the "loudness" of the raindrops hitting the water, that we can distinguish from the sound of the waves and wind. Very crispy.
A sonic beacon transponder transmitting at a known frequency, no problem from at least 50 miles. Two or three subs and you are triangulated very quickly. If the black boxes are pinging we're on them already.
Also, the speed indicators on the instrument panel of this aircraft were ordered to be replaced on April 27 because of this same problem and the work was to be done upon landing, oops.
Don't tempt them to surrender to the waves, traveling on the surface is challenging enough.
The pitot-based system cannot. It measures speed relative to the air, not ground speed. Again, the pitot A/S sensors are used for fly-by-wire FLIGHT-CONTROL, not nav.
Inertial-guidance has been used for a long time for navigation. However, the gyros drift and the 'fix' needs to be corrected frequently. GPS is preferred for navigation.
A stall occurs when the airspeed is too LOW, not when it is increased. If the airspeed exceeds Vne, the plane will start to break apart, due to the air-flow induced forces on tail and/or wings.
Obama emasculated the United States and undermined Israel beyond anything the terrorist could have wished for. If Obama had not gushed, then they’d claim credit.
We’re back to the Clinton era. They’ll get four-five attacks without any notable response. Biden warned us of as much. This is how it will go, so long as the MSM keeps its absolute allegiance to Obama.
Else Obama needs to wag the dog => Obama doesn’t take criticism well, but then what Marxist does.
Thanks for the note.
Interesting.
Canada once defended herself proud, with her greatest day being 65 years ago today! If they stick with the likes of Harper they’ll get there again.
PAN-AM103 should have exploded over the Atlantic but the plane was delayed leaving Heathrow. Had it left on time, the culprits may never have been brought to justice.
French sub(s) are en route to the area.
I am with you in that.
They do. They don't have wings. They are called tanks.
That's the issue here, were the pilots able to correct from a likely stall and how could a stall have happened? Not many other ways for this plane to come apart other than over-speeding due to bad indicators and a steep dive. It is known that the airframe catastrophically depressurized about 3 minutes after the 24 error messages went out. It happened so fast that the pilots never sent an emegency signal.
02:10Z: Autothrust off Autopilot off FBW alternate law Rudder Travel Limiter Fault TCAS fault due to antenna fault Flight Envelope Computation warning All pitot static ports lost
02:11Z: Failure of all three ADIRUs Failure of gyros of ISIS (attitude information lost)
02:12Z: ADIRUs Air Data disagree
02:13Z: Flight Management, Guidance and Envelope Computer fault PRIM 1 fault SEC 1 fault
02:14Z: Cabin Pressure Controller fault (cabin vertical speed)
Not much doubt a stall occurred, either from too little speed or excessive attitude and over-correction.
There appears to be too little time for a low speed stall over-corrected by diving for speed to then over-speed and get airframe failure.
In the Qantas Airbus incident, the pilots decided that the aircraft had stalled and then over-speeded simultaneously, which commanded a negative G pushover followed by a pitch up, suddenly climbing 300 feet and then abruptly pitched nose down into a steep dive.
The maneuver exceeded the design certification of the airframe. Luckily the pilots regained control, many passengers injured. That's why I theorize that over-speeding may have been the original problem causing a loss of control cascade.
In the case of the Airbus (and many other airplanes), wing/body design is a compromise of many factors.
The air at FL50 is very thin. At higher speeds, drag is increased. Drag that brings the nose up.
Gadalftb is correct, in this situation,with this airframe, more power/speed without proper retrimming, could cause a stall.
“02:10Z: Autothrust off Autopilot off FBW alternate law Rudder Travel Limiter Fault TCAS fault due to antenna fault ...”
The ‘alternate law’ rudder travel limiter fault suggests that the problems started in the rear.
Where is the antenna for the TCAS located? If you know.
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