The following article appeared in March-April 2000 issue of the "Quicklook Southern Ohio Hub" NATCA newsletter. This was an article written in "controller-to-controller" jargon, so as to explain to my colleagues at Port Columbus (and elsewhere) why I created this web site. [While most of you folks reading this are probably aviation oriented, and understand that acronyms are a part of life for anyone who works in the FAA, some of you may nevertheless find a number of the abbreviations unfamiliar. So here are definitions for many of those acronyms...ARTCC stands for "Air Route Traffic Control Center" (which we often just call "Center"), ZLA stands for Los Angeles Center, whereas ZOB stands for Cleveland Center (which is located in OBerlin, Ohio). UCR stands for Unsatisfactory Condition Report, and FPL for Full Performance Level. PVD is short for Plan View Display (another name for a radarscope at a Center), whereas DSR stands for Display System Replacement (the new radar scopes recently installed in the Centers). Also, where I state "Then last summer Linda, Than and I visited...," Linda is my "other half," and "Than" is short for Jonathan, our son.]
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On August 24, 1984 there was a midair collision between a Wings West Beech 99 and a single-engine Aero Commander in California. This collision occurred approximately 8 miles west-northwest of San Luis Obispo airport in ZLA's airspace. 17 people lost their lives.
In the ensuing investigation the controllers working the sector testified that the Aero Commander wasn't displayed, so there was no way they could have warned the Wings West flight. However, there was indisputable evidence that the Aero Commander was detected by radar, and it was squawking 1200 with Mode C. It was all there, plain-as-day, on ZLA's computer tapes. After a years worth of investigation the NTSB ruled that Los Angeles Center's equipment had to have displayed the Aero Commander's target.
I imagine that most people figured the controllers either weren't paying very close attention, or that they were flat out lying. I know that was my first impression. It just didn't make sense that two aircraft could be detected by the same radar, yet one wouldn't be displayed.
However, my impression changed on a fateful day around 15 years ago. That was during my previous life as a center controller at ZOB. I was working a Crown Airways Twin Otter. The pilot was VFR, just wanting an extra set of eyes looking out for him and his passengers while on their way toward making connections at U.S. Air's hub in Pittsburgh. His route of flight happened to be through the Clarion Sector, and I was those extra set of eyes behind the scope.
I had been a FPL controller for around a half-a-year by this time, and I was confident in my display of traffic on my PVD. One of the radar sites that served this area was located on a plateau near Clearfield, PA. Being high up on that hill it provided excellent low-altitude coverage, especially to the west. In fact, it was so good that we could see the aircraft's transponder reply while the aircraft was on the ground at Dubois airport, which was 17 miles away from that radar site! Dubois is where the Twin Otter had departed.
Shortly after departure the Twin Otter calls me, and I tag him up. Then, shortly after that, out-of-the-blue the Twin Otter pilot says "Center, DID YOU SEE THAT AIRCRAFT???!!!". Right after he said that, there appeared a 1200 squawk at his SIX O'CLOCK position. It wasn't there BEFORE that...
It was that incident that started me on a quest to figure out just what was taking place in the bowels of the ARTCC computer that determines how radar targets should be displayed. What I learned was that, YES, in certain circumstances an aircraft can be detected by radar, yet NOT displayed. I eventually wrote a UCR concerning this matter (1988). My findings weren't disputed, but the UCR was closed with no action taken (1989). Having exhausted my routes within the FAA to call attention to this problem, I then gave a presentation concerning this matter at the Sixth International Symposium on Aviation Psychology here in Columbus. My paper was subsequently published in their Proceedings (1991). A year later my paper was reprinted in The Journal of Air Traffic Control (a quarterly publication of the Air Traffic Control Association). In that paper I specifically alluded to the fact that the problem I discovered could have played a role in why the ZLA controllers did NOT see the Aero Commander in the San Luis Obispo midair collision. Naive me thought that might shake something lose and get my concerns addressed. Then along comes 1993 and I transferred down here and began the process of learning how to do this job from the tower & terminal radar side of the equation. So I put my concerns about ARTCC radar data processing and the San Luis Obispo midair collision on the back burner.
Then last summer Linda, Than and I visited close friends who lived across the street from us when I worked at ZOB. So I took the opportunity to stop up and see my colleagues from the past, and got a tour of the new control room (DSR). It was great to see my friends I had worked with for 11 years, and the new equipment was pretty neat, but much to my dismay I quickly ascertained that radar data processing hadn't changed. In spite of the billions of dollars in upgrades, the problem I had worked so hard to call attention to still existed.
Over the past several years I have shared my concerns with any and every aviation alphabet group and person that purports to care about aviation safety...but no one has taken up the cause. I finally determined that if no one else is going to do anything about this, I guess I better. I feel such a strong moral responsibility on this issue that I just can't let it drop.
As part of my tools to call attention to this problem, I am utilizing a terrific technology. It is called the World Wide Web! In the middle of January I got myself a book on how to create a web site, and armed with my iMac I was up and running by Feb 2nd. I've had 3 major updates since then.
In my latest update of Feb 27th I focus on the San Luis Obispo midair collision. In that regard I have written the NTSB with a formal "Petition for Reconsideration" concerning their findings. My web site is my supporting documentation that I refer the NTSB to.
You can link to my site from the terrific web site Steve "MM" Miller has created for NATCA CMH at http://cmh.natca.net, or proceed directly to my site by entering http://home.columbus.rr.com/lusch in your browser. I have an awful lot of supporting documentation there. If you're curious, I encourage you to go to my site and begin by clicking on my "Slide Show" for the rest of the story...
This page created March 18,2000, updated March 21, 2000.
© 2000 by Lusch's Midair Collision Investigations. All rights reserved.