"George Patterson" wrote in message
news:z8WCf.546$OY4.296@trndny02...

Then it would be pretty hard for a seaplane to be taking off there,
wouldn't it.


No, an amphibious seaplane could takeoff from ORD quite easily.



I've got the sectional right in front of me. The class B floor is 3,000'
or higher over the lake.


Good. Look at the shoreline and move your gaze about ten miles east.
You'll find magenta vignette there roughly parallel to the shoreline. Now
examine the chart legend to discover what magenta vignette means, you'll
find it in the lower left.

You wrote:

"Perfectly responsible. Even very close to ORD, the controlled airspace only
goes down to 3,000'. In other words, there's over 2,300' of airspace above
the lake
that's uncontrolled. It would actually be irresponsible to try to talk to
ORD;
the controllers there are some of the busiest people in the world, and they
have
no desire to talk with aircraft that are outside their area and intend to
remain so."

You said nothing about Class B airspace.



Now, you can be an asshole and try to pick nits if you like, but THERE'S
NO REQUIREMENT FOR THAT SEAPLANE TO TALK TO THE ORD CONTROLLERS PRIOR TO
THAT TAKEOFF, NOR WOULD THE ORD CONTROLLERS WANT TO HEAR FROM HIM.


That's correct, but do you now understand that controlled airspace begins at
700' above the lake surface, not at 2300' above it? I'd be happy to give
you further lessons in controlled airspace and chart reading if you like.