Hello all,
I would like to take my six month old miniature schnauzer puppy on a flight over Mother's Day weekend, so he can meet his Grandmother

The only pet carrier he fits into is Sherpa's large bag: 20"L X 11.75"W X 11.5"H. Do you think it'll fit underneath the seat okay? Continental said it can't exceed 45" in total, which it doesn't. However, he can't stand in it, but he can turn around. I'm worried we'll be turned away. Do you think we'll be okay?
Some friends who met him yesterday, one of which used to work for an airline, said he's too big and won't fit underneath the seat. But like I said, he fits comfortably in the large Sherpa bag, which is "airline approved." Is there any way I can confirm the bag will fit? Is it possible to take him in the bag to the airport prior to our trip and ask a counter agent for confirmation?
Thank you in advance for any and all advice!
Matt
PS: he's almost 17 lbs. Don't know if that matters or not.