New FDR Decode

reply to post by thomk



Tom, look at this post again:

posted on 8-12-2009 @ 12:30

Replace all the "WE" with "I", and that is what I specifically do.

I already told you were I received my training.

In what specific field?

Electronics. Analog / Digital.

A majority of my field experience has been RF related.

Training on the job is all hands-on. Also meetings with Eng. departments
for updates.

[edit on 8-12-2009 by turbofan]

Originally posted by 911files

Originally posted by 767doctor

Originally posted by thomk


I'll reciprocate. I got my BS Mechanical Engineering from Cornell U. in the early 70's. I've been a Project engineer & product design engineer ever since. I've been in charge of running projects & designing high tech equipment for about 35 years. As I mentioned before, products that I have designed and built have gone to the bottom of the Marianas Trench, to Saturn & into about 100,000 human hearts. Oh yeah, I've got over 50 patents.

Now, please give me a sense of what, exactly, is your job where you work.

TomK

Braggart!

That's okay, I got my degree from a box of Cracker Jack's. A Cracker Jack degree is much better than one from Cornell.

Definitely a lot cheaper & a lot less work.

But also a lot less fun.

It's hard to imagine that, back in the early 70s, we thought that $5K/year seemed like an outrageous amount to spend for college.

Boy have times changed...

Tom

[edit on 8-12-2009 by thomk]

Originally posted by thomkWhat are you talking about. This is a pretty absurd statement.

Without a connection, data does not get from point A to point B. Point A is the door sensor circuit. Point B is the FDR.

It's not absurd if you actually had a manual to reference.

There is NO CONNECTION to the FDR from the door sensor. NONE.
NOTHING. NADA. ZIP.

The FLight Data Recorder [FDR] is a storage device. It receives a
serial data stream from the Data Acquistion Unit [DAU] in binary form.

FDR stores data, it does not have physical connections from discrete sensors.

If you had the detailed schematics, you could trace it the whole way.

No, you cannot.

The detailed schematic that I have DOES NOT show a connection from
the door sensor to the FDR.

It's all data storage which is not part of the physical connection / wiring
found in a schematic.

You will get as far as the EICAS in this case, and then it's a dead end.
The rest is processed within the EICAS and sent via a data link to the
remainder of the system.

In other words, you could not trouble shoot a failed open/close state
update from the door sensor all the way to storing the bit within the
FDR using a schematic. That's not the intended use of a schematic in
the sense of this 757 manual.

[edit on 8-12-2009 by turbofan]

Originally posted by weedwhacker

(good stuff snipped out)

What does that mean? Well, I'll tell you. It is common to re-position airplanes when they are on overnights. "MX Taxi"...yes, some mechanics are fully trained, using the same simulators pilots train in, to start and taxi the jets. They know how to use the radio, too.

Now...do you P4T folks want to claim that even when taxiing by MX, they bother to close the cockpit door???

Good point.

Not only this, but when we do layover checks(don't know what other airlines call them), we typically do idle engine runs to check the oil levels. Layovers are done every night on the line, so even if the plane wasn't taxied by mechanics, the engines were certainly run at least twice by mx.

Originally posted by thomk


Definitely a lot cheaper & a lot less work.

But also a lot less fun.

It's hard to imagine that, back in the early 70s, we thought that $5K/year seemed like an outrageous amount to spend for college.

Oh my, I was in the POST academy in California during that time. When I worked in Yosemite we were police/fire combo's so I had to do the California State Fire Marshall's Arson and Fire Investigation school too (hey Craig, that should be an easy one for you to check out). When I got back to Tennessee I did a few years with the University of TN at Martin as a Campus police officer. My job was to stop all of that fun ya'll was having

But I digress. I did not go to college until the late 80's and early 90's after I left police work. By that time I was too old for fun and since I was paying for it out of pocket, I required nothing but A's for my money. Try working full-time and maintainig a 4.0 GPA in mathematics at the same time. Yeah, maybe that was fun now that I think about it.

I still think the Cracker Jack degree is the best though.

Good point.

Not only this, but when we do layover checks(don't know what other airlines call them), we typically do idle engine runs to check the oil levels. Layovers are done every night on the line, so even if the plane wasn't taxied by mechanics, the engines were certainly run at least twice by mx.

If this is indeed correct we can shut the book on this one.

42 hours of recorded operation, both in flight and on the ground and inclusive of scheduled flights and checks/maintenance, and the FDR does not record a single instance of the door opening.

Keep flinging excrement at the wall, JFK. The laws of probability suggest that one day you'll get at least one of your basic assertions correct, but given your record over the last few pages I'd suggest you'll be waiting a while.

[edit on 8-12-2009 by discombobulator]

Originally posted by 911files
Oh my, I was in the POST academy in California during that time. When I worked in Yosemite we were police/fire combo's so I had to do the California State Fire Marshall's Arson and Fire Investigation school too (hey Craig, that should be an easy one for you to check out).

I spent 1 to 3 months of about every year from 77 - 92 in Camp 4, or living out of a converted step van in the Yosemite Lodge parking lot, dodging the rangers.

You were probably one of the guys banging on my door, that I had to ignore...

LMAO...

Tom

Originally posted by discombobulator

Good point.

Not only this, but when we do layover checks(don't know what other airlines call them), we typically do idle engine runs to check the oil levels. Layovers are done every night on the line, so even if the plane wasn't taxied by mechanics, the engines were certainly run at least twice by mx.

If this is indeed correct we can shut the book on this one.

42 hours of recorded operation, both in flight and on the ground and inclusive of scheduled flights and checks/maintenance, and the FDR does not record a single instance of the door opening.

Bobby will undoubtedly come back with some kind of bs about mechanics "whipping" these checks. Sure it happens, but typically not anything dealing with the engines, especially something as easy as engine oils.

[edit on 8-12-2009 by 767doctor]

Here is a rough break-down for flight #11, an LAX-IAD flight on 9/9/2001.

19:52:02 - Engine start
20:03:26 - Wheels leave ground (indicated by RA changes)
00:22:43 - Wheels touch down
00:27:45 - Engine stop

So, around 4 1/2 hours of no restroom, no coffee, no snack, no flirting with the attendants.

And I did find a case of something pointed out by weedwacker...

Originally posted by weedwhacker
[At some point during the previous recorded data, at some place, given that span of time, maintenance had control of the airplane numerous times.

Here is one specific case I found.

Subframe
113926 - 07:02:26
until
113941 - 07:02:39

The flight before ended at 01:32:29 and the next at 14:07:11. Obviously some kind of maintenance activity, and since they feared for their lives, they had the FLT DECK DOOR closed.

Originally posted by thomk

Originally posted by 911files
Oh my, I was in the POST academy in California during that time. When I worked in Yosemite we were police/fire combo's so I had to do the California State Fire Marshall's Arson and Fire Investigation school too (hey Craig, that should be an easy one for you to check out).

I spent 1 to 3 months of about every year from 77 - 92 in Camp 4, or living out of a converted step van in the Yosemite Lodge parking lot, dodging the rangers.

You were probably one of the guys banging on my door, that I had to ignore...

LMAO...

Tom

That was you

Refresh my memory...ain't that the camp the climbing bums hung out in just nw of Yosemite Lodge?

ETA: Turns out Camp 4 has its own Wiki page.
Camp 4

Thought that might help others keep up with what we are talking about. Man, I could tell you some stories, but a little off topic me thinks.

[edit on 8-12-2009 by 911files]

Originally posted by 911files
Here is a rough break-down for flight #11, an LAX-IAD flight on 9/9/2001.

19:52:02 - Engine start
20:03:26 - Wheels leave ground (indicated by RA changes)
00:22:43 - Wheels touch down
00:27:45 - Engine stop

So, around 4 1/2 hours of no restroom, no coffee, no snack, no flirting with the attendants.

And I did find a case of something pointed out by weedwacker...

Originally posted by weedwhacker
[At some point during the previous recorded data, at some place, given that span of time, maintenance had control of the airplane numerous times.

Here is one specific case I found.

Subframe
113926 - 07:02:26
until
113941 - 07:02:39

The flight before ended at 01:32:29 and the next at 14:07:11. Obviously some kind of maintenance activity, and since they feared for their lives, they had the FLT DECK DOOR closed.

Weedwhacker, you're a frickin genius!

13 seconds! thats a heck of a short engine run! Those AA guys have it down!
Probably just doing a check of the PIMU's(engine fault reporting units) which simulate engine thrust momentarily.

Good job 911 files!

And still none of you "experts" have attempted to answer MY question and have resorted to ad homs because I asked.

Therefore I am forced to conclude that there is NO data path from the surge tank sensors to either the EICAS, FDAU, or FDR.

Since the official FOIA release DOES have that value recorded in the FDR output ( AAL77_tabular.csv, column 106 ) AND it is a value which DOES fluctuate I am forced to draw the conclusion that that FOIA release is fake.

Thanks guys.

Originally posted by JFrickenK
And still none of you "experts" have attempted to answer MY question and have resorted to ad homs because I asked.

Therefore I am forced to conclude that there is NO data path from the surge tank sensors to either the EICAS, FDAU, or FDR.

Since the official FOIA release DOES have that value recorded in the FDR output ( AAL77_tabular.csv, column 106 ) AND it is a value which DOES fluctuate I am forced to draw the conclusion that that FOIA release is fake.

Thanks guys.

See, told ya he was going to put a different spin on things to divert attention from the major P4T fail.

So my question now is where exactly did this AAL77_tabular.csv actually come from...

A quick search resulted in www.aal77.com...

So was it the NTSB which faked the data ( doubtful ) or was the John Farmer which posts here ( much more likely )?

Take it for what you will.

Originally posted by JFrickenK
Take it for what you will.

The last desperate grasps from a bunch of kooks?

We all knew where this was heading... either Warren was going to go under the bus or there'd be a declaration that the data is fake.

And really, you've made so many off the wall assertions that have immediately been proven false (you being debunked by turbofan was a highlight) that noone really cares about your questions or whatever preconceived conclusion you've arrived at.

Originally posted by discombobulator

Originally posted by JFrickenK
Take it for what you will.

The last desperate grasps from a bunch of kooks?

We all knew where this was heading... either Warren was going to go under the bus or there'd be a declaration that the data is fake.

And really, you've made so many off the wall assertions that have immediately been proven false (you being debunked by turbofan was a highlight) that noone really cares about your questions or whatever preconceived conclusion you've arrived at.

I have yet to see a data path from that sensor to the EICAS, FDAU or FDR.

I will retract once you show me one.

Originally posted by JFrickenK
And still none of you "experts" have attempted to answer MY question and have resorted to ad homs because I asked.

Therefore I am forced to conclude that there is NO data path from the surge tank sensors to either the EICAS, FDAU, or FDR.

You conclude "no data path" based on what information, exactly??

Originally posted by JFrickenK
Since the official FOIA release DOES have that value recorded in the FDR output ( AAL77_tabular.csv, column 106 ) AND it is a value which DOES fluctuate I am forced to draw the conclusion that that FOIA release is fake.

LMAO.

Thanks for a PERFECT demonstration of how "PfffT logic" (if you'll excuse the oxymoron) works.

And why it so consistently fails.


TomK

reply to post by JFrickenK


I'm still working on the question, sorry I haven't had much time to study
the manual.

From what I did look at, the tank sensor module outputs a single, TTL level
voltage using NAND logic. Unless this is a mult-plexed source, I don't
believe I've found the proper signal path.

A NAND gate will simply output a low/high state in the inverse of what
you would expect to see from an "AND" gate circuit.

The numbers in column 106 require more than a single bit to process...

Give me until this evening to locate the remainder of this circuit and any
further connections.

Originally posted by JFrickenK
I have yet to see a data path from that sensor to the EICAS, FDAU or FDR.

You couldn't see the Forward Access Door either.

Originally posted by JFrickenK

Originally posted by discombobulator

Originally posted by JFrickenK
Take it for what you will.

The last desperate grasps from a bunch of kooks?

We all knew where this was heading... either Warren was going to go under the bus or there'd be a declaration that the data is fake.

And really, you've made so many off the wall assertions that have immediately been proven false (you being debunked by turbofan was a highlight) that noone really cares about your questions or whatever preconceived conclusion you've arrived at.

I have yet to see a data path from that sensor to the EICAS, FDAU or FDR.

I will retract once you show me one.

And I've yet to see you demonstrate the huevos to attempt to unravel my assertions about the "swapped pilots".

If I were feeling a bit immature this morning, I believe that my response might go something like "bwaak, bwaaaak, BWAAAAAK!"

Sure is a good thing that I'm not feeling immature this morning, ain't it?!

TomK