Hi, your mom's tumor might be well be treatable with radiation therapy such as GammaKnife (GK), CyberKnife (CK), or Fractionated Stereotactic Radiation (FSR). Surgery is also an option.
While this is all scary, it is very treatable.
Before I go further, please understand, I am an unusual case.
I have a left side CPA meningioma. When it was detected, it was significantly larger, about the size of a golf ball. It is right on an artery so it has a very good blood supply and was very "sticky." It was also deep into my neck. So, my surgery was extraordinarily long at 32 hours - very unusual. They were able to remove about 90-95% of it and I spent about three months recovering before returning to work. Two years later, after it was determined to be growing again, it was treated with 28 sessions of FSR (low dosage radiation).
4.5 years later it is showing signs of the tumor shrinking and most everyone agrees with me that I am pretty wonderful.
You can read a detailed story at
http://randomdatablog.com/brain-tumor/Your mom probably has plenty of time to consider treatment options and get multiple opinions. She probably does not have to rush. As for flying, I think most patients are able to fly about two weeks post-surgery.
There are a variety of possible side effects, but there really seems no way to predict them. Please read the materials available from the ANA - you will find those helpful.
-Tod