AF447
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Coagie, can you reconcile your proposed scenario with the locations of the bodies and wreckage after 7 or more days of drift at sea? Somehow the plane apparently made some serious travel in the reverse direction of its flight plan from its last reported position. The distance may have been big enough that a significant portion of that travel took place after the last ACARS message. Some REALLY accurate back tracking on the drift of objects is needed to get some kind of estimate of where the plane went down. Appearances are that it did not go down at its 02:10:34 position or further along its flight plan.
So losing the tail in a scenario that requires it be blown off forward BUT with damage to its rudder's lower edges rather than tipping off.
There is a nice way to get a "feel" for what the BEA folks saw at the base of the VS if you're modestly handy with tools. Take a piece of paper and a small board, say 2.5cm by 2.5cm by 30cm. Cut a slot most of the way through the board lengthwise in the middle of one side. Slide the piece of paper into the slot. Get some short dowel rod. Cut off three pieces about 3 to 4 cm long. Find a drill a little larger than the diameter of the rod. Drill three holes through the board and paper in the "front" 2/3 of the paper and slot. Don't have the hole drilled in the paper actually break the edge of the paper. Slip in the pieces of dowel rod. Now grab the the paper with both hands in a "prayer" position and pull up and "forward". Notice the tears in the paper at the hole positions is not symmetrical. This allows you to figure out which way it was broken loose. It is on this basis the BEA made its pronouncement.
You can see this to a lesser degree pulling paper out unevenly from a three ring binder.
I believe they have a very good notion of that direction the VS was trying to move as it was pried loose. And I think I have a half a good guess on how this happened. It does not include breaking off in flight.
The theories are fun. But it's more interesting when you can fit the theory to the very limited set of facts present.
JD-EE
So losing the tail in a scenario that requires it be blown off forward BUT with damage to its rudder's lower edges rather than tipping off.
There is a nice way to get a "feel" for what the BEA folks saw at the base of the VS if you're modestly handy with tools. Take a piece of paper and a small board, say 2.5cm by 2.5cm by 30cm. Cut a slot most of the way through the board lengthwise in the middle of one side. Slide the piece of paper into the slot. Get some short dowel rod. Cut off three pieces about 3 to 4 cm long. Find a drill a little larger than the diameter of the rod. Drill three holes through the board and paper in the "front" 2/3 of the paper and slot. Don't have the hole drilled in the paper actually break the edge of the paper. Slip in the pieces of dowel rod. Now grab the the paper with both hands in a "prayer" position and pull up and "forward". Notice the tears in the paper at the hole positions is not symmetrical. This allows you to figure out which way it was broken loose. It is on this basis the BEA made its pronouncement.
You can see this to a lesser degree pulling paper out unevenly from a three ring binder.
I believe they have a very good notion of that direction the VS was trying to move as it was pried loose. And I think I have a half a good guess on how this happened. It does not include breaking off in flight.
The theories are fun. But it's more interesting when you can fit the theory to the very limited set of facts present.
JD-EE
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Vertical velocity at impact
As there were a lot of ACARS messages within the 2h 10 'window', could the aircraft already have been in trouble (and starting to drop) sometime before, say between 2h 08 and 2h 09? Also if ACARS stopped because both engines had been lost (physical or flame-out)the impact could be sometime after 2h 14, say between 2h 15 and 2h 16. This would give a descent time of 6 to 8 minutes. If terminal velocity was reached quite quickly, this would give an impact velocity of about 5000 ft/min
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All aspects of the flight prior to 0210Z show a functioning aircrew, doing a serious job of keeping ahead of the aircraft, proposing some strict R/T procedures...
Can someone here who has experience/knowledge of ADS-C answer this: once an initial connection has been attempted, could the system automatically generate further attempts - especially at the 20 mins threshhold when it detects that the connection has not been made? Or can the crew program the system to make further attempts? The BEA report says that the first connection has to be made by the crew - but could the BEA mean that the initial attempt at a connection has to be made by the crew?
I appreciate that there may well be a perfectly mundane explanation for the 25 minutes silence, but as this is the only comm I believe it is worth asking the question.
My first post - have been reading this from day 1, but it is easy to miss things/forget what you have read, so apologies if this has already been answered - but I don't believe that it has.
Last edited by Jag6; 17th Jul 2009 at 09:40. Reason: Facts re estimated time at TASIL
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Rational between ACARS messages.
augustusjeremy, re #3694
It is not just the 'IR2 fault' message that questions the 'blocked pitot theory'.
As the BEA report reiterates, the ACARS messages are maintenance messages for the ground crew, not warnings to the flight crew. A maintenance message that is generated by a system's BITE should be due to that system's BITE detecting an internal fault:-
1 NAV TCAS FAULT Message.
As indicated in the BEA report (page 50) the cause is unclear. I suspect that the most vital parameter derived by TCAS is the relative velocity with respect to other aircraft. As well as a BITE check on max and min, I would expect the rate of change of such a vital parameter to be checked. A rate of change of more than about 20 knots per second for say ten samples might be considered as out of spec and hence warrant a maintenance fault message.
2 ADR Fault.
It is not clear as to the level of inconsistency between the three ADRs; the statements within the BEA report seem to conflict. On page 50 regarding NAV ADR DISAGREE message, “Meaning: This message indicates that the EFCSs have rejected an ADR, and then identified an inconsistency between the two remaining ADRs on one of the monitored parameters.”, but on page 51 regarding the PROBE-PITOT message, “...triggered one of the speed monitoring processes: they have detected a decrease of more than 30 kt in one second of the 'polled' speed value. The three ADRs were considered valid by the EFCS2 at the time the monitoring was triggered... “.
3 ISIS SPEED OR MACH FUNCTION
Presumably this could due to the same cause as for the ADR Fault; what a shame that the CMC does not send the flag status, just a single character representing 'flags code' would give so much information at so little cost! Or if the info in post #1442 is correct (but #1757 is not), this could be a problem with gyro derived direction.
It is not just the 'IR2 fault' message that questions the 'blocked pitot theory'.
As the BEA report reiterates, the ACARS messages are maintenance messages for the ground crew, not warnings to the flight crew. A maintenance message that is generated by a system's BITE should be due to that system's BITE detecting an internal fault:-
1 NAV TCAS FAULT Message.
As indicated in the BEA report (page 50) the cause is unclear. I suspect that the most vital parameter derived by TCAS is the relative velocity with respect to other aircraft. As well as a BITE check on max and min, I would expect the rate of change of such a vital parameter to be checked. A rate of change of more than about 20 knots per second for say ten samples might be considered as out of spec and hence warrant a maintenance fault message.
2 ADR Fault.
It is not clear as to the level of inconsistency between the three ADRs; the statements within the BEA report seem to conflict. On page 50 regarding NAV ADR DISAGREE message, “Meaning: This message indicates that the EFCSs have rejected an ADR, and then identified an inconsistency between the two remaining ADRs on one of the monitored parameters.”, but on page 51 regarding the PROBE-PITOT message, “...triggered one of the speed monitoring processes: they have detected a decrease of more than 30 kt in one second of the 'polled' speed value. The three ADRs were considered valid by the EFCS2 at the time the monitoring was triggered... “.
3 ISIS SPEED OR MACH FUNCTION
Presumably this could due to the same cause as for the ADR Fault; what a shame that the CMC does not send the flag status, just a single character representing 'flags code' would give so much information at so little cost! Or if the info in post #1442 is correct (but #1757 is not), this could be a problem with gyro derived direction.
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Agreed Kilomikedelta....
3700+ posts (including the deleted ones) based on some photos, cryptic BEA reports and archival meteorological satellite data? I would say that 99% of the postings are egocentric masturbations by people with lots of hubris, too much time on their hands and regrets about their contribution to society.
Regards
Last edited by Captain104; 17th Jul 2009 at 11:53. Reason: spelling
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Originally Posted by llagonne66
PJ2
As stated somewhere above (or maybe in the previous thread), Honeywell ADIRUs (P/N HG2030AE22) are installed on AF A330s.
As stated somewhere above (or maybe in the previous thread), Honeywell ADIRUs (P/N HG2030AE22) are installed on AF A330s.
Last edited by Robin42; 17th Jul 2009 at 09:54. Reason: remove lengthy url from quote
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TCAS
VicMel:
What other aircraft? The one 80 miles in trail? TCAS has no airspeed input. Relative velocity with targets depends on tracking them via TCAS/transponder link, and not onboard data. Altitude difference, rate of closure, and time to CPA, closest point of approach, are the TCAS triggers.
I'm with BEA that this fail remains unanswered, and unrelated to the other faults, which can be tied back to faulty airspeed.
GB
1 NAV TCAS FAULT Message.
As indicated in the BEA report (page 50) the cause is unclear. I suspect that the most vital parameter derived by TCAS is the relative velocity with respect to other aircraft. As well as a BITE check on max and min, I would expect the rate of change of such a vital parameter to be checked. A rate of change of more than about 20 knots per second for say ten samples might be considered as out of spec and hence warrant a maintenance fault message.
As indicated in the BEA report (page 50) the cause is unclear. I suspect that the most vital parameter derived by TCAS is the relative velocity with respect to other aircraft. As well as a BITE check on max and min, I would expect the rate of change of such a vital parameter to be checked. A rate of change of more than about 20 knots per second for say ten samples might be considered as out of spec and hence warrant a maintenance fault message.
I'm with BEA that this fail remains unanswered, and unrelated to the other faults, which can be tied back to faulty airspeed.
GB
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All aspects of the flight prior to 0210Z show a functioning aircrew, doing a serious job of keeping ahead of the aircraft, proposing some strict R/T procedures...
Actually, I think that this statement needs examination. From 1:35 until 2:14 the only crew action of which we are aware is their third attempt to establish the ADS-C link with Dakar ATC at 2:01. No other comms at all. Having made two attempts at 1:33 & 1:35, the crew then apparantly waited another 25 minutes, until the last possible minute to meet ADS-C requirements, to make their third try. The BEA report says that the minimum ADS-C requirement is reporting 20 mins ahead of entry into Dakar FIR; 2:01 is just about 20 mins ahead of their estimated time at TASIL (actually I believe 2:20 was Atlantico ATC's projection, not the crew's estimate).
Can someone here who has experience/knowledge of ADS-C answer this: once an initial connection has been attempted, could the system automatically generate further attempts - especially at the 20 mins threshhold when it detects that the connection has not been made? Or can the crew program the system to make further attempts? The BEA report says that the first connection has to be made by the crew - but could the BEA mean that the initial attempt at a connection has to be made by the crew?
I appreciate that there may well be a perfectly mundane explanation for the 25 minutes silence, but as this is the only comm I believe it is worth asking the question.
My first post - have been reading this from day 1, but it is easy to miss things/forget what you have read, so apologies if this has already been answered - but I don't believe that it has.
Can someone here who has experience/knowledge of ADS-C answer this: once an initial connection has been attempted, could the system automatically generate further attempts - especially at the 20 mins threshhold when it detects that the connection has not been made? Or can the crew program the system to make further attempts? The BEA report says that the first connection has to be made by the crew - but could the BEA mean that the initial attempt at a connection has to be made by the crew?
I appreciate that there may well be a perfectly mundane explanation for the 25 minutes silence, but as this is the only comm I believe it is worth asking the question.
My first post - have been reading this from day 1, but it is easy to miss things/forget what you have read, so apologies if this has already been answered - but I don't believe that it has.
But then, again...what do I know?
I'm just an...
arrogant to judge on a crew's action without a modicum 1/-of experience of flying through the ITCZ and 2/-in the comfort of an armchair.
These guys had one hour and six minutes of flight worth in fuel
(...) (1) Contingency fuel —
Fuel that is not less than 5 % of the planned trip fuel or, in the event of in-flight replanning, 5 %
of the trip fuel for the remainder of the flight; and (...)
Fuel that is not less than 5 % of the planned trip fuel or, in the event of in-flight replanning, 5 %
of the trip fuel for the remainder of the flight; and (...)
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TCAs - groundspeed
TCAS has no airspeed input
I suppose - please correct me if i am wrong - that groundspeed is provided by the Inertial Reference Units only (not ADRs).
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TCAS has no speed input at all. Honeywell uses the attitude input to select which TCAS antenna to use for target tracking. Collins uses relative signal strength instead. TCAS is interested in rate of closure.
GB
GB
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tcas altitude
TCAS has no speed input at all. Honeywell uses the attitude input to select which TCAS antenna to use for target tracking. Collins uses relative signal strength instead. TCAS is interested in rate of closure.
I wonder how TCAs gets altitude information... GPS only, GPS with IRS, IRS only, baro/altitude input from ADRs (with or without eventually computing airspeed (pitots) for adjustements ?)
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Hi,
All will be happy if you publish your source(s)
Bye.
Guyana newspapers report a large section of AF 447 and other items have been washed up there. Clearly the search wasn't 100%
Bye.
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Quote:
Guyana newspapers report a large section of AF 447 and other items have been washed up there. Clearly the search wasn't 100%
Yes indeed. I've looked at 6 online Guyanan newspapers and not one
has any mention of this.
Guyana newspapers report a large section of AF 447 and other items have been washed up there. Clearly the search wasn't 100%
Yes indeed. I've looked at 6 online Guyanan newspapers and not one
has any mention of this.
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VicMel
As I understand it, you cannot be certain there is an IR2 fault - IR2 is the first of the systems that is reporting the ADIRU2 (1FP2), HARD fault. All explained on page 48 of the English translation. So the fault may not be the IR but some other portion of the ADIRU. I stand to be corrected if the (1FP2) bit gives that information, as I don't have a clue what it means.
It is not just the 'IR2 fault' message that questions the 'blocked pitot theory'.
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Graybeard
Given that the sequence of ACARS reporting is indistinct, and attitude is a parameter for TCAS antenna sequestering, what of IRU moaning has to do with its (TCAS) fault? Loss of attitude management could even explain the a/p trip. Turbulence? FCPC? TCAS fault is not inexplicable.
Holding ACARS loosely, which I do, a genesis of fault reporting could begin while 447 was "on flight path" and the "last reported" position may have been an accurate record of several minutes of heading, altitude, airspeed discrepancies contributing to an upset.
Why hold ACARS loosely? BEA included only the data originally leaked to France2. Essentially, granting it provenance.
Fair enough, but why then withold the "remaining" data?? (FromRobin42, above).
If one takes ACARS (the system and this specific data) with a grain of salt, there would be fewer "theories" to be bolstered by "FDR style" "official" data that comes from a maintenance tool, ACARS.
Given that the sequence of ACARS reporting is indistinct, and attitude is a parameter for TCAS antenna sequestering, what of IRU moaning has to do with its (TCAS) fault? Loss of attitude management could even explain the a/p trip. Turbulence? FCPC? TCAS fault is not inexplicable.
Holding ACARS loosely, which I do, a genesis of fault reporting could begin while 447 was "on flight path" and the "last reported" position may have been an accurate record of several minutes of heading, altitude, airspeed discrepancies contributing to an upset.
Why hold ACARS loosely? BEA included only the data originally leaked to France2. Essentially, granting it provenance.
Fair enough, but why then withold the "remaining" data?? (FromRobin42, above).
If one takes ACARS (the system and this specific data) with a grain of salt, there would be fewer "theories" to be bolstered by "FDR style" "official" data that comes from a maintenance tool, ACARS.
Last edited by Will Fraser; 17th Jul 2009 at 14:21.
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Further, if 447 was lost at 0214+, that would time the messages at ~four minutes, and its prelude possibly ~4 minutes. If, as above, the a/c was on published route, perhaps until 0206, when attitude and turbulence induced handling qualities diminished, the time span of accident behaviour would be ~8 minutes, an average ROD of 4,500fpm. Consistent with BEA, its speed at impact would be somewhat higher.
The four minute reporting frame supports a flight path without large heading and altitude excursions (no "spin", no "disintegration"). Not without its challenges, this mode may have then deteriorated (rather than recovered as in Q and NW), to produce the flight aspects at entry suggested by BEA.
Will
The four minute reporting frame supports a flight path without large heading and altitude excursions (no "spin", no "disintegration"). Not without its challenges, this mode may have then deteriorated (rather than recovered as in Q and NW), to produce the flight aspects at entry suggested by BEA.
Will
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Pars of wreckage found on shores of Guyana
Air France Airbus A330-200 crash: Wreckage, sensory equipment recovered on local shores
July 17, 2009 | By Christopher | Filed Under News
By Gary Eleazar
Dennis Baksh, a farmer from Ann’s Grove, East Coast Demerara, knew that he had stumbled on to something valuable last Friday whilst on the Hope Beach.
Baksh had found what is believed to be a part of the fuselage and a component believed to be the first piece of sensory equipment recovered from Air France Airbus A330-200 that crashed into the Atlantic Ocean after leaving neighbouring Brazil en route to France on June 1.
According to Baksh, he immediately realized that what he had found was not a part of a boat and as such made arrangements to have a tractor haul the piece of debris to his home, some distance inland.
“I see it pun deh seawall and when a go and check I say that this got to be a part of a plane,” said Baksh, yesterday.
A close up of the sensory equipment
The man who made the important discovery said that he did not see any other piece of debris in the area.
The sensory component that was attached to the fuselage is a three-axis Inertial Measurement Unit (IMU) which is cylindrical in shape and is mounted on a flat base with electrical wiring protruding from within it. It bears the trademark ‘Sensorex.’
Baksh attempted to open the device but only managed to break into the cylindrical case; the cube within was impenetrable to Baksh.
A GCAA official said that he noted the numbers on the fuselage and on the equipment marked Sensorex and that he would be forwarding these to the relevant authorities.
Another aviation official explained that the piece of equipment marked Sensorex might be the first piece of sensory equipment retrieved from the crashed plane. He explained that it sends signals to the flight panel and this might be the piece of malfunctioning equipment that caused the crash.
An Inertial Measurement Unit (IMU) is the main component of inertial guidance systems used in air, space, and watercraft, including guided missiles.
An IMU works by sensing motion including the type, rate, and direction of that motion using a combination of accelerometers and gyroscopes.
The data collected from these sensors allows a computer to track a craft’s position, using a method known as dead reckoning.
The IMU works by detecting the current rate of acceleration, as well as changes in rotational attributes, including pitch, roll and yaw.
The data is then fed into a computer, which calculates the current speed and position, given a known initial speed and position.
For example, if an IMU installed in an airplane were to detect that the craft accelerated westward, resulting in a calculated, constant speed of 500 miles per hour, and detected no other accelerations for one hour, then the guidance computer would deduce that the plane must be 500 miles west of its initial position.
When combined with a computerized system of maps, the guidance system could use this method to show a pilot where the plane is located geographically, similar to a GPS navigation system but without the need to communicate with any outside components, such as satellites.
The term IMU is widely used to refer to a box containing three accelerometers and three gyroscopes. The accelerometers are placed such that their measuring axes are orthogonal to each other. They measure inertial acceleration, also known as G-forces.
Three gyroscopes are placed in a similar orthogonal pattern, measuring rotational position in reference to an arbitrarily chosen coordinate system.
IMUs are primarily used in vehicle-installed inertial guidance systems. Today almost every commercial or military water-going vessel has one.
Most aircraft are also equipped with IMUs.
Dennis Baksh displays the sensory component alongside the fuselage believed to be that from the Air France Airbus A330-200 that crashed in the Atlantic Ocean on June 1 last.
When Baksh found the piece of fuselage, he said that there was also a thick foam-like material attached to the inside of the piece of fuselage but this he removed given that while it was water soaked it made the already heavy piece of debris almost immovable.
The Police and the Guyana Civil Aviation Authority were subsequently contacted with the latter confirming that the piece of debris was definitely from a large aircraft and that the component bearing the trademark Sensorex was indeed a piece of sensory equipment used on aircrafts.
The Brazilian Embassy was also contacted.
At present, it is still unclear what caused the crash that killed 228 persons aboard.
The aircraft was flying in turbulent weather at the time but some international analysts have said it is unlikely that the weather contributed to the crash but are not ruling it out completely.
Chief Air France spokesman Francois Brousse had suggested the plane could have been struck by lightning but most experts say lightning doesn’t usually bring down a modern airliner, unless it coincides with other factors that contribute to the accident.
“Planes are built with lightning strikes in mind and are struck reasonably frequently,” according to Patrick Smith, a U.S. commercial pilot and aviation writer.
Aviation safety statistics indicate that each large passenger jet such as the Airbus A330 is struck by lightning about once every three years on average.
Searching for any markings on the fuselage.
Regional aircraft, however, which fly at lower altitudes, are hit more frequently, about once a year.
About seven hours after taking off and flying through the night over the mid-Atlantic, the pilots of the Air France Airbus reported that they had encountered an area of intense cumulonimbus activity, part of the massive thunderstorms that regularly batter the region
Air France reported that the aircraft’s ACARS (Aircraft Communications and Addressing System) a digital datalink that automatically transmits service messages from the aircraft to ground stations messaged the company’s headquarters regarding a problem with the aircraft’s electrical and pressurization systems.
The French aircraft accident investigation agency, the Bureau d’Enquetes et d’Analyses (BEA) had announced that an examination of structural components of the aircraft recovered from the surface of the ocean revealed that they were deformed from the bottom to the top.
This according BEA suggests that the aircraft hit the sea “in the direction of flight and with a sharp vertical acceleration”. This, in turn, indicates that the aircraft was “not destroyed in flight”. The aeroplane’s speed sensors were “a factor but not the cause” of the disaster.
The investigators had also determined that no distress call was made, either to air traffic control or to other aircraft.
The most direct evidence of the cause of the accident is the presence of suspected aircraft debris on the ocean surface and a series of 24 automatically generated maintenance messages that were transmitted from the plane shortly before the crash.
Investigators also said that messages indicated that cabin pressure was lost and there was some kind of electrical system failure.
Air France Airbus A330-200 crash: Wreckage, sensory equipment recovered on local shores : Kaieteur News
July 17, 2009 | By Christopher | Filed Under News
By Gary Eleazar
Dennis Baksh, a farmer from Ann’s Grove, East Coast Demerara, knew that he had stumbled on to something valuable last Friday whilst on the Hope Beach.
Baksh had found what is believed to be a part of the fuselage and a component believed to be the first piece of sensory equipment recovered from Air France Airbus A330-200 that crashed into the Atlantic Ocean after leaving neighbouring Brazil en route to France on June 1.
According to Baksh, he immediately realized that what he had found was not a part of a boat and as such made arrangements to have a tractor haul the piece of debris to his home, some distance inland.
“I see it pun deh seawall and when a go and check I say that this got to be a part of a plane,” said Baksh, yesterday.
A close up of the sensory equipment The man who made the important discovery said that he did not see any other piece of debris in the area.
The sensory component that was attached to the fuselage is a three-axis Inertial Measurement Unit (IMU) which is cylindrical in shape and is mounted on a flat base with electrical wiring protruding from within it. It bears the trademark ‘Sensorex.’
Baksh attempted to open the device but only managed to break into the cylindrical case; the cube within was impenetrable to Baksh.
A GCAA official said that he noted the numbers on the fuselage and on the equipment marked Sensorex and that he would be forwarding these to the relevant authorities.
Another aviation official explained that the piece of equipment marked Sensorex might be the first piece of sensory equipment retrieved from the crashed plane. He explained that it sends signals to the flight panel and this might be the piece of malfunctioning equipment that caused the crash.
An Inertial Measurement Unit (IMU) is the main component of inertial guidance systems used in air, space, and watercraft, including guided missiles.
An IMU works by sensing motion including the type, rate, and direction of that motion using a combination of accelerometers and gyroscopes.
The data collected from these sensors allows a computer to track a craft’s position, using a method known as dead reckoning.
The IMU works by detecting the current rate of acceleration, as well as changes in rotational attributes, including pitch, roll and yaw.
The data is then fed into a computer, which calculates the current speed and position, given a known initial speed and position.
For example, if an IMU installed in an airplane were to detect that the craft accelerated westward, resulting in a calculated, constant speed of 500 miles per hour, and detected no other accelerations for one hour, then the guidance computer would deduce that the plane must be 500 miles west of its initial position.
When combined with a computerized system of maps, the guidance system could use this method to show a pilot where the plane is located geographically, similar to a GPS navigation system but without the need to communicate with any outside components, such as satellites.
The term IMU is widely used to refer to a box containing three accelerometers and three gyroscopes. The accelerometers are placed such that their measuring axes are orthogonal to each other. They measure inertial acceleration, also known as G-forces.
Three gyroscopes are placed in a similar orthogonal pattern, measuring rotational position in reference to an arbitrarily chosen coordinate system.
IMUs are primarily used in vehicle-installed inertial guidance systems. Today almost every commercial or military water-going vessel has one.
Most aircraft are also equipped with IMUs.
Dennis Baksh displays the sensory component alongside the fuselage believed to be that from the Air France Airbus A330-200 that crashed in the Atlantic Ocean on June 1 last.When Baksh found the piece of fuselage, he said that there was also a thick foam-like material attached to the inside of the piece of fuselage but this he removed given that while it was water soaked it made the already heavy piece of debris almost immovable.
The Police and the Guyana Civil Aviation Authority were subsequently contacted with the latter confirming that the piece of debris was definitely from a large aircraft and that the component bearing the trademark Sensorex was indeed a piece of sensory equipment used on aircrafts.
The Brazilian Embassy was also contacted.
At present, it is still unclear what caused the crash that killed 228 persons aboard.
The aircraft was flying in turbulent weather at the time but some international analysts have said it is unlikely that the weather contributed to the crash but are not ruling it out completely.
Chief Air France spokesman Francois Brousse had suggested the plane could have been struck by lightning but most experts say lightning doesn’t usually bring down a modern airliner, unless it coincides with other factors that contribute to the accident.
“Planes are built with lightning strikes in mind and are struck reasonably frequently,” according to Patrick Smith, a U.S. commercial pilot and aviation writer.
Aviation safety statistics indicate that each large passenger jet such as the Airbus A330 is struck by lightning about once every three years on average.
Searching for any markings on the fuselage.Regional aircraft, however, which fly at lower altitudes, are hit more frequently, about once a year.
About seven hours after taking off and flying through the night over the mid-Atlantic, the pilots of the Air France Airbus reported that they had encountered an area of intense cumulonimbus activity, part of the massive thunderstorms that regularly batter the region
Air France reported that the aircraft’s ACARS (Aircraft Communications and Addressing System) a digital datalink that automatically transmits service messages from the aircraft to ground stations messaged the company’s headquarters regarding a problem with the aircraft’s electrical and pressurization systems.
The French aircraft accident investigation agency, the Bureau d’Enquetes et d’Analyses (BEA) had announced that an examination of structural components of the aircraft recovered from the surface of the ocean revealed that they were deformed from the bottom to the top.
This according BEA suggests that the aircraft hit the sea “in the direction of flight and with a sharp vertical acceleration”. This, in turn, indicates that the aircraft was “not destroyed in flight”. The aeroplane’s speed sensors were “a factor but not the cause” of the disaster.
The investigators had also determined that no distress call was made, either to air traffic control or to other aircraft.
The most direct evidence of the cause of the accident is the presence of suspected aircraft debris on the ocean surface and a series of 24 automatically generated maintenance messages that were transmitted from the plane shortly before the crash.
Investigators also said that messages indicated that cabin pressure was lost and there was some kind of electrical system failure.
Air France Airbus A330-200 crash: Wreckage, sensory equipment recovered on local shores : Kaieteur News
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