Hi Agincourt:

I have not flown on a CP 747 for a long while, so I can't really compare for you. But I do fly on the AC A-340's every week in the summer.

The economy seats are very nice on this plane. They have little wings on the headrests so you can fall asleep without your head winding up on the shoulder of the person in the next seat. The seats are nicely contoured and quite comfortable - obviously the airline considered that the passengers' asses would be in them for 8 or more hours. I think there is also a footrest on each seat, but I can't recall for sure. The seats are made by Recaro.

In my opinion, the best place to sit in the A-340 economy cabin is as far to the rear as you can, ideally get a window seat or an aisle that is beside a window seat. This is a very quiet plane (uses 4 small engines, same engine as a B-737, not those really big fans like a 747 has), so there is no exterior noise penalty associated with sitting at the rear. There is generally a lot less disturbance from the food carts, other passengers, etc. if you sit at the back. Plus you are close to the coffee pot if you want a cup.

Enjoy your trip.