Another interesting find from the http://www.911workinggroup.org files.
"AAT-200" is a special investigation agency inside the FAA and deals with aircraft accidents, emergency cases, near mid-air collisions, and other irregular incidents. As soon as an accident occurs, the involved controllers are obligated to submit a report to AAT-200:
http://www.faa.gov/airports_airtraffic/air_traffic/publications/atpubs/atq/APNDX%2010.htm#_ftn1
The information flow is: local FAA facility -> Regional Operations Center (ROC) -> Washington Operations Center (WOC) -> AAT-200. Example: if an accident occurs in the skies over Ohio, Cleveland Center controllers (responsible for Ohio) send their reports to the Great Lakes Regional Operations Center where it is passed on to the WOC and finally the AAT-200.
On 9/11/2001 at 7:30 p.m. AAT-200 updated a request list from the facilities involved in the attacks:
AEA - Voice and CDR data in RAPTOR format from:
New York TRACON Time 0930-1015ET........................ Received
Washington National - Pentagon................................... Received
Dulles - Both Pentagon and Camp David incidents..........received
Pittsburgh - Camp David incident....................................Received
Washington Center radar for AAL77................................Received
Washington Center voice..................................................Received
New York Center radar....................................................Received
New York Center voice replay.........................................Received
Voice tape Millville AFSS..................................................Waiting
AGL - Voice and CRD in RAPTOR format:
Cleveland for UAL1898................................................Waiting
Cleveland Center radar for AAL77..................................Received
Cleveland Center voice replay for AAL11......................Received
Indianapolis Center radar................................................Received
Indianapolis voice tape via telephone.............................Received
Cleveland Center radar for DAL1989.............................Waiting
Cleveland Center voice for DAL1989..............................Waiting
ANE - Boston Center radar and voice replay................Received
http://woodybox.info/5 AWA 755 Package Docs on AAT-200 LAN 91101 Subfolder REDACT.pdf
The list addresses FAA en-route centers (identifiable by the affix "Center") and airports. In the latter cases, the affix "airport" is obviously seen as redundant and omitted (Washington National = Washington National Airport).
I have highlighted the most interesting entry. "Cleveland" stands for Cleveland Hopkins Airport (as distinct from Cleveland Center). This means that controllers at Hopkins had reported an incident (emergency landing or the like) involving United 1898. They reported it to AAT-200 via the Great Lakes Regional Operations Center (AGL). And AAT-200 was still waiting for voice and CRD data.
However, the BTS database ( http://www.bts.gov ) reveals that United Airlines operated no aircraft with flight number 1898 on 9/11. In plane language: There was no United 1898. So what airliner was being reported by the controllers of Cleveland Hopkins?
In the light of Cleveland mayor Michael White's famous news conference and ample additional evidence that an airliner with unknown identity made an emergency landing at Hopkins "United 1898" looks like an excellent candidate for this mystery plane:
http://911woodybox.blogspot.com/2007/02/cleveland-airport-mystery.html
http://911review.org/inn.globalfreepress/Cleveland_Airport_Mystery.html
Interestingly, Delta 1989, the plane that also landed at Hopkins and apparently functioned as a cover-up for the mysterious emergency landing, was not reported by Cleveland Airport, but Cleveland Center. This means that Delta 1989 was not seen as an emergency case by airport controllers and therefore not reported to AAT-200. The reason why it was reported by en-route controllers remains to be investigated.
More interestingly, the flight numbers of the two airliners - 1989 and 1898 - are very similar and easy to confound, a curiosity amplifying the impression that Delta 1989 was used as camouflage to send the other plane into oblivion.
Most interestingly, the airline of the mysterious plane seems to be United. The controllers were maybe not able to check if the flight number 1898 was operational , but they were certainly able to recognize the United markings.
The most authentic report on the incident was delivered by the Akron Beacon Journal http://911review.org/brad.com/Woodybox/JET-93_land-Ohio.html ):
Cleveland Mayor Michael White said at a news conference this morning that a Boeing 767 out of Boston made an emergency landing at Cleveland Hopkins International Airport because of fears a bomb was aboard.
Combining this newspaper report with the AAT-200 paper results in the conclusion that a United Boeing 767 from Boston landed in emergency at Cleveland Hopkins.
The number of the United Boeing 767's departing from Boston is so small that it should narrow down the search for the identity of the mysterious plane considerably.
