Founded in 2000
Why Some Pilots and Air Traffic Controllers Don't See UAP

James McClenahen
Air Traffic Control Specialist (ret.)
NARCAP Technical Specialist

NARCAP headquarters received an interesting report concerning a UAP
sighting on August 1, 2001 near Chicago's O'Hare airport at 2015
local time. A cylindrically shaped self-luminous, orange/gold
colored object without wings or tail was seen between O'Hare and
Midway airports and appeared to fly faster than other jet aircraft
seen at the same time but at similar altitudes. It allegedly slowed
down as a B-757 commercial aircraft took off to the west from Midway
and then accelerated out of sight to the NE. Both past the witnesses
location in clear view. Since this part of the nation handles some of
the highest air traffic density in the country there is extensive
radar coverage available to help maintain traffic separation. The
airport control towers at these airports also afford excellent 360
degree visibility for tens of miles in good visibility conditions. We
asked our ATC specialist, Jim McClenahen to comment on this
interesting case. Here are his surprising comments.


Nice to hear from you. My first take on this is that it would be
like finding a needle in the haystack but would be worth a try. The
reason I say this, the controllers and cockpit crews in the Chicago
terminal area are extremely busy. There is so much information being
passed between controllers and cockpit crews due to traffic volume
which requires everyone to really pay attention to all details, so,
when something like this happens the chances of the controllers or
cockpit crews experiencing it are slim.

I will try to find a contact source in the tower, but we have
somewhat of a blind spot, because of the complexity of the airspace.
Example, the report made reference of a B 757 departing Midway, the
cockpit crew of this flight was in the middle of departing, climbing,
cleaning up the aircraft for initial climb, and making a radio change
to departure control (Chicago TRACON). My point is, this crew is
busy and on top of that they are listening for any traffic and
watching their TCAS for traffic too!

The B727 mentioned was probably on Chicago Approach talking to either
a feeder controller or the final controller, being set up for the
runway complex the flight to land on. The report indicates the
weather was VFR and it is a good possibility the approaches in use
were ILS and Visuals. This means the cockpit crew was also extremely
busy. Not only were they setting up the aircraft for landing, they
were probably looking for traffic they were following so they could
conduct the visual approach. They were also watching for other
traffic and monitoring their TCAS equipment while expecting a
frequency change to the tower once they completed setting up for the

In addition, the approach controller would not really have time to
observe anything unusual on the radar (ASR-9, which is a digital
presentation). If that controller was busy, he would be watching
only the aircraft he was working. This holds true for the tower
controllers as well. When they get more traffic to handle, they
concentrate on the aircraft they are working. They focus out
surrounding items that are not important to them.

I hope this makes sense to you and please ask questions or if you
want. I can call you and discuss this further on the phone. I
would guess if anyone saw anything from the tower, it would be someone
not directly working aircraft such as a supervisor, a coordinator, or
traffic management specialist, maybe even a person working flight
data/clearance delivery. Of course this is just a guess based on my
Why Some Pilots and Air Traffic Controllers Don't See UAP
James McClenahan