New FDR Decode

Originally posted by 767doctor

No, you're still wrong. The sensor is the static port; a transducer converts one form of signal to another(pressure to electrical signal). Two different concepts, skippy.

Wow, I can't believe I'm having this discussion!

www.mfg.mtu.edu...

See that "doctor" all transducers contain a sensor! It contains a sensor
so that it can SENSE changes in something! Therefore a transducer is
also commonly known as a SENSOR.

Take it home and think about it. If you still feel you're right, contact
the vendors and MFG's in the link I posted and tell them to remove
the word SENSOR beneath the pictures of transducers, and to remove
the word SENSOR from the keyword search for their transducers!

What you intially said, and are still saying is that there is some electrcal signal originating outside the ADC. YOU ARE WRONG. It's all pneumatic outside the ADC, inside is where the pressure gets converted to an electrical value.

WOW. SLOW DOWN "Doctor"!

Are you saying the Air Data Computer is also the transducer?

In other words, the Air Data Computer is a box with a transducer (SENSOR)
inside?

So, to get a mental picture...

There is a static PORT, with a flex line connecting the ADC to the static
port. No wires.

Inside ADC frame I will find a transducer converting pressure to electric
signals which are sensed from the flex line (connected to the static PORT)?

IOW: The ADC has an integrated sensor and there are no external wires
leading to sensors?

Ryan Mackey seems to think the PA was erroneous due to "Compressibility" issues.

Do you agree 767Doctor?

Your evasion of the DFDR and DFDAU points noted. I'll take that as an agreement of the statements made regarding recording of the FLT DECK DOOR parameter.

[edit on 29-11-2009 by R_Mackey]

Originally posted by R_Mackey

The documentation was provided above. The 1997 regulation and therefore amendment in DFL applies to all 757's DFDAU. As you correctly pointed out, if a parameter is not used, its just left open from the DFDAU and not connected to any recorder. Therefore it will not be recorded on the FDR as seen on the UA93 data, UA93 NTSB pdf's, etc. (FLT DECK DOOR is not there), but it is displayed on the AA77 data and pdf's.

I notice my question went unanswered. Did PfT decode both raw files, that is AA77 and UA93, with the same version data frame layouts? A "yes" or "no" will suffice.

Perhaps you wish to offer the theory that the FLT DECK DOOR parameter was grounded at the DFDAU port and hooked up the the DFDR to waste memory on AA77 DFDR? Care to sign your name and credentials to such a theory?

Eh? Strawman much?

Provide a quote where P4T says doors are "NEVER" opened on short flights or admit you prefer to use strawman arguments. I want to see a direct quote from P4T with the word "NEVER".

4.5 or less according to Warren Stutt. But your attempt to stretch the truth towards your extreme bias noted.

Okay, another question unanswered. I'll ask again: What is PFT's offical position of security of the flight deck door, post 9/11? Is it different than pre-911?

Originally posted by 767doctor
I notice my question went unanswered. Did PfT decode both raw files, that is AA77 and UA93, with the same version data frame layouts? A "yes" or "no" will suffice.

I don't know personally. But I do know that the NTSB lists FLT DECK Door as a parameter for AA77, and it is in the data, but they do not list it for UA93. Why do you think that is? NTSB incompetence again? Have you decoded UA93 data? Surely an Avionics Tech as yourself have the resources to do so? Have you decoded AA77 data to verify it with P4T and Warren's decodes? Or do you just take this AA77 data at face value because some of it may support your bias for the govt story....

Eh? Strawman much?

Asking a question is not a strawman. You claiming P4T's "official position" is that the cockpit door is NEVER opened on short flights without providing source, is a strawman. Please familiarize yourself with the definition of a strawman argument.

Okay, another question unanswered. I'll ask again: What is PFT's offical position of security of the flight deck door, post 9/11? Is it different than pre-911?

you never asked, You assumed their position and were unable to provide a source. Now you ask the question. Very good 767Doctor, you're learning.

My answer. I don't know. Have you emailed them? I did provide links in this thread on page 40 to their discussion of the topic. Have you read them?

Originally posted by turbofan

Originally posted by 767doctor

No, you're still wrong. The sensor is the static port; a transducer converts one form of signal to another(pressure to electrical signal). Two different concepts, skippy.

Wow, I can't believe I'm having this discussion!

www.mfg.mtu.edu...

See that "doctor" all transducers contain a sensor! It contains a sensor
so that it can SENSE changes in something! Therefore a transducer is
also commonly known as a SENSOR.

Take it home and think about it. If you still feel you're right, contact
the vendors and MFG's in the link I posted and tell them to remove
the word SENSOR beneath the pictures of transducers, and to remove
the word SENSOR from the keyword search for their transducers!

What you intially said, and are still saying is that there is some electrcal signal originating outside the ADC. YOU ARE WRONG. It's all pneumatic outside the ADC, inside is where the pressure gets converted to an electrical value.

WOW. SLOW DOWN "Doctor"!

Are you saying the Air Data Computer is also the transducer?

In other words, the Air Data Computer is a box with a transducer (SENSOR)
inside?

So, to get a mental picture...

There is a static PORT, with a flex line connecting the ADC to the static
port. No wires.

Inside ADC frame I will find a transducer converting pressure to electric
signals which are sensed from the flex line (connected to the static PORT)?

IOW: The ADC has an integrated sensor and there are no external wires
leading to sensors?

You can google all you like, but you cant google away 14 years avionics experience and proper training in the field. Apparently, you have zero formal training in the field(and it shows) and rely on your google-fu to support your arguments. Transducers and sensors are two different things, all the googling in the world won't change that. Certain devices use both to the same end, but the concept of sensing a stimuli(sensor) and converting that energy from one form to another(transducer) are entirely different electrical concepts.

4th time. There is no external electrical sensor outside the ADC.

Are you saying the Air Data Computer is also the transducer?

In other words, the Air Data Computer is a box with a transducer (SENSOR)
inside?

So, to get a mental picture...

There is a static PORT, with a flex line connecting the ADC to the static
port. No wires.

Inside ADC frame I will find a transducer converting pressure to electric
signals which are sensed from the flex line (connected to the static PORT)?

IOW: The ADC has an integrated sensor and there are no external wires
leading to sensors?

The light has just come on, congrats. Now you just need to figure out difference bewteen a sensor and a transducer. Heres a hint: I've told twice already.


[edit on 29-11-2009 by 767doctor]

[edit on 29-11-2009 by 767doctor]

Originally posted by R_Mackey
Ryan Mackey seems to think the PA was erroneous due to "Compressibility" issues.

Do you agree 767Doctor?

Your evasion of the DFDR and DFDAU points noted. I'll take that as an agreement of the statements made regarding recording of the FLT DECK DOOR parameter.

[edit on 29-11-2009 by R_Mackey]

Yes, I agree with Mackey. Why? Because compressibility lowers the pressure around the static ports, which would produce a higher altitude reading. However, I'm not married to the theory. I've always said the reason PA reads too high is mostly pneumatic lag.

Originally posted by 767doctor
Yes, I agree with Mackey. Why? Because compressibility lowers the pressure around the static ports, which would produce a higher altitude reading. However, I'm not married to the theory. I've always said the reason PA reads too high is mostly pneumatic lag.

Ok good, You do realize Ryan also says compressibility becomes an issue above Mcrit, right?

So, you must also agree .70M - .72M is above Mcrit for the 757?

Care to put your name behind that Jay, based at Atlanta, for Delta?

Originally posted by R_Mackey

Originally posted by 767doctor
Yes, I agree with Mackey. Why? Because compressibility lowers the pressure around the static ports, which would produce a higher altitude reading. However, I'm not married to the theory. I've always said the reason PA reads too high is mostly pneumatic lag.

Ok good, You do realize Ryan also says compressibility becomes an issue above Mcrit, right?

So, you must also agree .70M - .72M is above Mcrit for the 757?

Care to put your name behind that Jay, based at Atlanta, for Delta?

Ooh, you have figured out my first name...I'm skeered.

When air approaches the speed of sound, however, "compressibility" sets in. What it means is that under the right conditions, we can no longer assume density is constant, and thus neither can we assume static pressure is constant. Applied to an aircraft, this can happen even at aircraft speeds below Mach 1 -- hence there is no clean distinction between subsonic and supersonic when aircraft are involved. We call this overlap the "transonic" regime. But why does it happen?

Why is because the aircraft shape accelerates the flow. If the aircraft is traveling at the critical Mach number, which can be as low as about 0.6, this means that at some point, probably flowing over the wings, the airflow is accelerated to the point that it becomes supersonic. When that happens, we can no longer treat the air as constant pressure, or constant density.

Source
forums.randi.org...

An avionics tech at Delta and a claimed NASA Scientist thinks .70-.72M is above Mcrit for the 757 affecting the static system. Funny.

And I know your last name too Jay. So do many Core Members of P4T, especially those at Delta.

Ok, enough fun for one day. Enjoy your night!

[edit on 29-11-2009 by R_Mackey]

Last post before I re-lurk as I'd like to enjoy the rest of my weekend without have to repeat myself every 5 minutes.

Originally posted by R_Mackey


I don't know personally. But I do know that the NTSB lists FLT DECK Door as a parameter for AA77, and it is in the data, but they do not list it for UA93. Why do you think that is? NTSB incompetence again? Have you decoded UA93 data? Surely an Avionics Tech as yourself have the resources to do so? Have you decoded AA77 data to verify it with P4T and Warren's decodes? Or do you just take this AA77 data at face value because some of it may support your bias for the govt story....

Okay, can you get back to me on that? The reason is probably because they used different frame descriptors since the two planes used different FDR models(hence, different FDAUs).

Asking a question is not a strawman. You claiming P4T's "official position" is that the cockpit door is NEVER opened on short flights without providing source, is a strawman. Please familiarize yourself with the definition of a strawman argument.

Well, it seems you guys needed evidence when someone stated they observed an open cockpit door on a 2 hour flight. Why would you need evidence, if this is a common thing?

So, I'm still unclear: is it PFT's contention that flight deck doors are never to be opened in flight, of flight durations less than x hours? If not, how does your group reconcile the 41 hours of the door never opening, even on a 4.5 hour flight?

Since some people are enjoying mixing up terms in this thread (which is what they do to cloud the issue), I thought I would post this for general background purposes.

[atsimg]http://files.abovetopsecret.com/images/member/cc5908d909b2.jpg[/atsimg]

This is from the Factual Specialist Report. Yes, the 757-3B format (ARINC 573/717) for the serial bit stream is used. That is the serial stream sent to the actual reorder from the DAU (in this case a DFDAU). In the case of AAL77, the DAU function is performed BY the FDR (more specificly the SSFDR). So Warren is using the correct frame layout for the FDR.

Here is the part that Turbo and company seem to be missing. The parameter (all of them for that matter) are sent to the DAU (as indicated by stuff turbo posted already). That must be done by physically "wiring" the subject of the parameter and is a logic issue completely different from what is stored in the FDR record. To date, there has been no evidence presented that was done, and no reason to argue it was because there has been no evidence presented that it was required to be.

However, that logic signal is not what is stored in the record. The DAU takes all of the inputs and converts them into a binary serial stream which is simply a defined sequence of bits (0's and 1's). The FDR is required to store at least 25 hours of flight operation. In order to extend that capability, the serial bit stream is compressed using a Huffman algorithm (a programming logic operation). So what is stored is NOT the logic posted by turbo, but an encoded form of the serial bit stream (serial data stream).

So simply because the FDR (meaning DFDAU and SSFDR) was updated to handle the 757-3B frame format, that all of the hardware was added to the plane to accept all of the parameters in the frame layout. I am not a plane mechanic, but I suspect this would be a very laborious and expensive undertaking. Only those required by FAA regulations would have been done if a penny-crunching operations manager was involved somewhere (which I am sure there was). So without evidence that this was done....

Beyond that, the data is first compressed. External software is required to uncompress it. Warren worked out the file structure into a CSV format (using C#) years ago. I adapted his code to VB.NET, but we both ended up in the same place. Without the compression algorithm, the data was virtually useless. A few months ago, Warren deciphered the algoritm (he is programming genius). So now he and others are able to work directly with the serial bit stream data. So when we are talking about 0's and 1's, we are talking about defined values in a serial bit stream of a defined length called a frame. Using the frame layout, the 12 bit WORD's represented in the stream are interpreted by software and given a specific meaning based on the frame layout definitions. So if there is no parameter being captured by the DAU, then there will be no values added to the stream. It will remain a value of 0 (default). It will be interpreted by the software reading the stream for that parameter as whatever the frame layout defines a 0 to mean. In this case, CLOSED.

The only way to prove the parameter was ever being recorded is if there is a value other than 0 at that position in the stream. In this case, there are none to be found.

[edit on 29-11-2009 by 911files]

[edit on 29-11-2009 by 911files]

Here's a question:

Would a forcible entry through the door be recorded? If this particular plane required the pilot to press a button in order to open the door, will a forcible entry (thereby not using the button or switch) be recorded. The switch or button hasn't been touched but the door could have been opened by force.

Originally posted by R_Mackey

And I know your last name too Jay. So do many Core Members of P4T, especially those at Delta.

There you have it. The most thought provoking post by the leader of P4T!

neener neener... i know your last name.... neener neener...



[edit on 29-11-2009 by ImAPepper]

reply to post by R_Mackey


Wow Robby,

Just can't admit when you're wrong, can ya?

Originally posted by R_Mackey

Originally posted by tomk52
I CAN take off in my little Cessna with a broken piece of equipment, without a MEL, as long as I meet the requirements of 91.213(d).

So, you can take off in your little Cessna without seat belts? Wings? Engine? Landing Gear? Seats? a Control yoke? A throttle lever? Mixture Lever? The list goes on, amateur.

Let the smoke screen, hand waving, tap dancing, goal post moving (and 27 other euphemisms for "lying") begin...

You did NOT say "you can't take off with a broken seat belts".
You did NOT say "you can't take off with a broken Wings".
You did NOT say "you can't take off with a broken Engine".
You did NOT say "you can't take off with a broken Landing Gear".
You did NOT say "you can't take off with a broken Seats".
You did NOT say "you can't take off with a broken Control yoke".
You did NOT say "you can't take off with a broken throttle lever".
You did NOT say "you can't take off with a broken Mixture Lever".

You DID say (and I quote to be specific):

Originally posted by R_Mackey
In other words, if you don't have an approved MEL, you cannot fly with so much as an overhead sun visor broken (if installed) unless approved by the FAA. If you have done so in your little Cessna, you busted regs.

And I say that you are wrong. I say that I can take off with a broken visor. Or several other possible pieces of equipment. As long as I did so while following the procedures required in 91.213(d).

Right or wrong?

Remember, just a few posts ago, you were giving me a ration about inability to make concessions, sport.

Originally posted by R_Mackey
How many Cessna 172's have you flown which have an MEL?

Irrelevant to the question.


TomK

reply to post by 767doctor


Geez, this is what we're dealing with huh? I send the guy links to
manufacturer sites that have the word "SENSOR" under their pictures
of transducers, but "Doc" still can't come to terms.

I send "Doc" a link to how tranducers function which also shows the
SENSING side of the transducer...but still it's not a type of sensor
according to "Doc"

lastly the very function of the transducer is to SENSE pressure and convert
it to electric signals...therefore it MUST HAVE a sensor...but "doc" says
it's not a type of sensor?

I guess my 18 years of military and aerospace field electronics (incl. College) experience doesn't account for much? I mean, i work with
pressure SENSORS everyday in my lab. Have a look at the vacuum
chambers we use to simulate space environments:



Well I had enough of playing semantics with Mr. "Doctor". All that matters
is PA is measured using an electrical sensor and NOT an aneriod altimeter
which was the whole point of the debate 10 pages ago. So, we'll carry
forward then!

As for John Farmer, he still can't come to terms with the parameter inclusion.
Was there any other sensor added in that "Change" that can be extracted
from the FDR file, which was NOT updating?

I mean someone went through the trouble to assign pins, figure logic states, add header info, program word, frame and bit positions, etc.
But naaaaaaa, it wasn't monitoring the door? Interesting logic sir.


[edit on 29-11-2009 by turbofan]

[dbl.post]

[edit on 29-11-2009 by turbofan]

Originally posted by turbofan
As for John Farmer, he still can't come to terms with the parameter inclusion. Was there any other sensor added in that "Change" that can be extracted from the FDR file, which was NOT updating?

Sorry Turbo, you guys are the one's making the claim it was. Now prove it.

I'm asking if you know off hand, because I'm at work and do not have the data in front of me.

Are there any updated parameters from that change in 1997 (year?)
INCLUDED in the FDR decode that do not update?

[edit on 29-11-2009 by turbofan]

Originally posted by turbofan
reply to post by 911files

 

While TomK get his kicks trying to figure out the meaning of my posts,
and whether or not my eyesight needs checking, I will remind him that
I apologized for thinking the acronym ASI originally said VSI.

Ahhh, after 10 postings of "you're an idiot", "you're ignorant", and "you're a fraud" because I repeatedly pointed out to you that your statements were wrong, your lame, non-apologetic "Ooops, it was my computer screen's fault, and it doesn't matter anyway" is supposed to ... what ... eliminate the fact that you claim avionics knowledge but don't YET know how a VSI works?

Originally posted by turbofan
TomK still has about five major errors to forgive us for ...

Ahh, that's OK. I forgive you & Robby & any other "us" on whose behalf you are beseeching my forgiveness.

In fact, since you asked so nicely, I forgive you for far, FAR more than 5 major errors.

Nice of you to ask, tho.

English much?

Originally posted by turbofan
I will also remind him we are contacting 757 mechanics to verify the operation of the switch and possibly get a MFG and model of the switch...as the manual does not contain such information....nor is it really important.
Is it going to change your mind if Honeywell makes the switch, over Rockwell?

Contact all the 757 mechanics you want. You'll get a damn sight better batch of info than you can provide.
Meanwhile, I never asked, and am not interested in, the connection to the FDR (not the switch) that you will find does not exist.
I asked you to provide the manufacturer & model for the altimeter & VSI pressure transducer whose data is recorded in the FDR.

Originally posted by turbofan
John Farmer, I already PROVED to you in many ways that the flight deck
door was recorded.

#1. It's in the FDR file.

#2. The door switch has an assignment in the Boeing documentation
along with assigned logic states.

#3. All parameters in the FDR file update. Can you find an example of
a parameter in the FDR file that is just hanging around taking up memory
space?

And I can prove to you - with PRECISELY ZERO DOUBT - that the door to that cockpit was opened during the flight. Regardless of what the FDR data does or does not say.

Ergo, I don't give a rat's butt about your DEMONSTRATED failed ability to read documentation.

See how nicely that works out?


TomK

[edit on 29-11-2009 by tomk52]

Originally posted by turbofan
I'm asking if you know off hand, because I'm at work and do not have the data in front of me.

Are there any updated parameters from that change in 1997 (year?)
INCLUDED in the FDR decode that do not update?

[edit on 29-11-2009 by turbofan]

And why should I go digging through the files to answer your question? You are the P4T tech guy...go figure it out for yourself.