Taking off IFR from an uncontrolled field today (severe clear), climbing Rwy Heading, making all the normal radio calls on Unicom as we had been since before departing. At about 1000' AGL we spot traffic at our 11o'clock & low.
I glance at the TCAS & notice it's a couple hundred feet below us so I pitch up to increase our climb rate a bit. There's another uncontrolled field immediately left and forward of our postion & it's pattern is coordinated with our departure airport's pattern as to avoid conflicts. Seconds go by and we realize the thing is climbing right towards us and even turning into our flight path.
Our departure from the pattern is to the right, to avoid the other field's pattern (and approaching head-on rules require right turns) so I initiate the turn early and keep climbing while we broadcast over Unicom once again and then contact Center to check in off of the uncontrolled field. In the meantime our traffic cranks & banks a left 180 while climbing like a banshee all of a sudden (remember we're turning out to the right & it was coming towards us so this is, again, right into our flightpath only their performance was ridiculous). "Is that a LEAR???"
Seems to me like they should have been listening, and broadcasting for that matter, on the Unicom frequency the two airports share while operating low-level in between the two close-by uncontrolled fields.
Seems to me like they realized we were right there all of a sudden and pulled the fancy chandelle maneuver a little recklessly.
§ 91.113 Right-of-way rules
e) Approaching head-on. When aircraft are approaching each other head-on, or nearly so, each pilot of each aircraft shall alter course to the right.
'What an idiot' I'm thinking. After we check in center queries the other airplane:
Center - "Flight Check did you see traffic 2 West of your position?"
Flight Check - "We need the GPS B again"
Center - "Roger..."
Us - "Flight Check??? Uggggghhhh"
MORAL OF THE STORY - keep your eyes peeled cause you never know
who's out there. Glad everyone had a safe day here as well as in HPN.