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Originally posted by backinblack
reply to post by roboe
Airplane becomes airborne, it starts recieving VOR data, it starts triangulating its position?
To 200' accuracy??
Even weedwhacker stated up to 2 miles deviation was acceptable...
Originally posted by backinblack
Originally posted by Reheat
Originally posted by backinblack
Mate, you contradict yourself in that post and call me a fraud etc.??
I am now convinced that your reading comprehension problem is intention unless the English Language is not your native tongue. You definitely need remedial reading help.
Interesting..Here's a few posts from you on this very page...
Yes, that is exactly what I'm saying, it's made up. There is no such thing as auto-align in either Commercial or Military Aircraft.
And then....
How would you know? I didn't say they could not align in-flight.
Are you freaking blind? Since when are auto-align and align the same thing?
Originally posted by backinblack
reply to post by Reheat
Are you freaking blind? Since when are auto-align and align the same thing?
What are you saying?
Do you think the pilot looks out the window, checks for points of reference, looks at his map and then puts in the new position.??
It's called "Auto Align" because the plane does it Automatically......
Originally posted by backinblack
reply to post by roboe
I've been to sites from both sides and no one seems to agree with that kind of accuracy..
Especially if the starting data is 3600' off and the plane was running INS with no GPS...
Originally posted by BCRFiles
weedwhacker, would you have departed if you saw a 3,000+ foot lat/llong offset on your HSI map, as is shown in the FDR data?
Capt Ralph Kolstad along with other American Airlines pilots and pilots from pprune say no, they wouldn't. So, why did this aircraft depart with such a large error in lat/long?
Originally posted by backinblack
This one I asked earlier..
Another poster "reheat" says the INS corrected itself by the end of the flight to an accuracy of 200'..
Can you tell me how it did that ???
Originally posted by Reheat
B00b Balsamo's...
B00by Balsamo.
Originally posted by weedwhacker
Generally, with all of those systems, in that time (pre-GPS updating, I repeat again) the INUs were NEVER counted on for "accuracy".
In the "Terminal Area" (that is generally considered to be operations, usually, below about 10,000 feet, and within about 30 miles of the airport (exact guidelines are not defined, the specifics vary by airport and locality) ...when operating in the most densely-occupied and busiest airspace, where more precision is required, the IRS was NOT the preferred reference for navigation. It was considered appropriate for en-route navigation, where separation standards have much more margin.
On departure, the references are usually from ground-based VORs...OR, simply radar vectors...so the controller decides where to "send" and to "point" the airplane....but, the controller will assign a future "route", when giving a radar vector....and, it is always implied anyway, per the filed flight plan (this is for that very rare contingency of communications failure. Old habit and procedures, from days long past, but still in force).
During the last decade, though....IRS accuracy, "tightness" and with GPS precision....it is so much more accurate that many more RNAV procedures have been adopted, specifically and ONLY for airplanes equipped with GPS-up-datable Inertial Nav Units systems. But, to repeat...this was NOT commonplace in 2001.
Finally...as to the old, pre-GPS IRS "drift"...it was constantly correcting it (them)selves...and, to repeat for emphasis once more, the airplane referenced and displayed the "triple mix" average of all three units.
To keep an "eye" on the "health" of each individual unit, it was (still is) a requirement to log into the aircraft LogBook, end of every flight, the "IRS accuracy" readings.
(I would have thought that Rob Balsamo, and Ralph Kolstad, of all people, knew this......funny, they omit explaining in proper detail, isn't it???)
The units keep track of elapsed time they are in align mode, for each flight...and the average amount of MILES they calculated their accumulated errors to be. The hours of operation are divided into the average "drift", and those numbers are displayed on an info page, you access from the menu....and you write those figures into specific places, in the LogBook, designed to record the values.
EVERY airline pilot (except, apparently, Ralph Kolstad) know all of this, already....that is why the vast majority of us laugh at the clowns of "P4T". It is only when they get so incredibly pesky, and become such irritants, spewing their ever-ridiculous DIS-info, that something needs to be "said" (written) to be put into the "O.O.R." (Official Online Record).
Because, as everyone should realize by now, nothing put out onto the Web every goes away. SO, FACTS must be sent out into the ether, in order to straighten out reality, and counter-act the crap.....
Originally posted by Thermo Klein
Originally posted by Reheat
B00b Balsamo's...
B00by Balsamo.
I would just like to point out that, in my opinion, your name-calling has no affect on what Mr. Balsamo said, it just makes you come across as an immature person who resorts to name calling.
The picture weedwhacker is referring to is this picture.
Source - www.abovetopsecret.com...
White is the lat/long according to PRES POS LAT/LONG (DEG) from the FDR file, Yellow and Red are radar returns. You can see them merge in flight.
The original source is John Farmer. Farmer claims he plotted the above course based on Lat/Long Coordinates from the FDR file.
Source - forums.randi.org...
The 3,000+ foot offset shown at IAD appears to merge in flight after departure according to John Farmer and the FDR Data.
How is this possible if the FDR data shows more than a 3,000+ foot offset before departure?
According to the links provided by Reheat and others, including the explanation given by weedwhacker, the Lat/Long positions are aligned on the ground prior to takeoff.
On the ground, the FMC position is based on the IRS position.
Since inertial systems accumulate position errors as a function of time, the position information being used by the FMC is slowly accumulating errors. These position errors can be detected by observing the position of the airplane on the HSI map. If an extended ground delay occurs and a significant map error is noticed the IRS should be realigned and present position re-entered.
Source - www.biggles-software.com...
weedwhacker, would you have departed if you saw a 3,000+ foot lat/llong offset on your HSI map, as is shown in the FDR data?
Capt Ralph Kolstad along with other American Airlines pilots and pilots from pprune say no, they wouldn't. So, why did this aircraft depart with such a large error in lat/long?
Weed I feel you're pulling some tricks on this post...
....why even mention INU.
Anyone who knows what an INU is knows you're just trying to put a discreding statement and connotation without actually saying anything.
Then you actually kill your own argument saying every pilot knows you need to check the books after each flight! If the ground error carried on from flight 11 to flight 12 (IAD -> Pentagon allegedly) then it would have been MORE likely to never have taken off with that huge error. I think you actually just helped the truthers in a big way.
Originally posted by weedwhacker
AND, the fact that the departure procedure was not RNAV-specific, nor dependent....
CAPITAL SEVEN DEPARTURE
TAKE-OFF RUNWAYS 1C, 1L, 1R: Climb heading 011° or as assigned, Thence. . .
TAKE-OFF RUNWAY 12: Climb heading 121° or as assigned, Thence. . .
TAKE-OFF RUNWAYS 19C, 19L, 19R: Climb heading 191° or as assigned, Thence. . .
TAKE-OFF RUNWAY 30: Climb heading 301° or as assigned, Thence. . .
. . Expect radar vectors to filed/assigned route or depicted fix. Maintain 3000,
expect clearance to filed altitude/flight level 10 minutes after departure.
Originally posted by weedwhacker
Capt Ralph Kolstad along with other American Airlines pilots and pilots from pprune say no, they wouldn't. So, why did this aircraft depart with such a large error in lat/long?
Huh? We have Kolstad, who put on such an embarrassing display for Jesse Ventura's TV show, making such claims? What, is he anal retentive or something? A pain in the butt to fly with, when he was still an active line pilot? Because, anyone who, on a day like that, in that kind of weather, would "worry or fret" over a minor map shift like that?? (BTW. 'map shift' is the proper term we use...you've pried it out of me.....I was waiting for one of the "P4T" clowns to mention it first, but alas....NOW you are even 'better' informed than before!! >sigh
weedy asked for a "10-9/9A" chart for Gate Coordinates so he can cross-check the IAD data. I initially corrected him that it's actually "20-9C" which contain the Lat/Long Coordinates for IAD Gates. (and most real pilots know this).