Route planning question

I'm planning to fly up to Oshawa Ontario next week (from Rochester, NY).
This will be my first flight there since I got my instrument rating. The
en-route chart shows an airway A21 going from the St. Catherines NDB to
Oshawa NDB. I have to confess that nothing I've read has ever said
anything about route planning with these sorts of airways (Alpha?). I was
thinking that I could do ROC v31 AIRCO v252 a21 OO, but there is no
defined intersection point between v252 and a21, so I'm not sure how the
ATC computers would handle that. I'm sure they don't want me to go all
the way into to YYZ and back out.

I figure in the real world I'll probably get direct OO long before I get
to that point, but I'd rather file something that won't get me a full
route clearance.

--
Paul Tomblin http://xcski.com/blogs/pt/
Home pages are the pet rock of the 90s. They all have them, they all think
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pretty embarrassed. -- Kim Alm