Embraer, which makes the popular E-Jet in the 70-122 seat market, is expected to formally launch its re-engined design of the E-175/190/195. (The 170 appears on its way out.)
The upgraded E-Jet will feature new wings, new systems, geared turbo fan engines by Pratt & Whitney and room for an additional eight to 12 passengers.
Embraer has been working diligently to line up solid orders to announce at the show.
Bombardier, on the other hand, doesn't traditionally do well at air shows.
Orders for its CSeries have been few and far between at these events, in part because Canadian securities laws require announcements within 24 hours of the signing of even letters of intent, making it virtually impossible for Bombardier to cluster announcements.
The first flight of the CSeries will almost certainly miss the air show, but is expected the next week.
Bombardier will have to be content talking about tests leading up to the first flight, revealing an unidentified customer's identify (possibly Odyssey Airlines, based on an executive's slip of the tongue at an industry event) and perhaps some small order announcements.
So, with all this activity, maneuvering and posturing, who will "win" the Paris Air Show?
Airbus, of course.
Scott Hamilton is an aviation writer and managing director of Leeham Co., which provides consulting services to the aerospace industry.