"150flivver" <timothywitt@hotmail.com> wrote

Why would you need pressurization if the altitude is only 12 grand?  A
pilot doesn't  even need supplemental oxygen unless he goes above 12
grand for more than 30 minutes.  With supplemental oxygen he's good to
a lot higher.  A turbocharged engine on the other hand would probably
be needed for those hot high density altitude conditions.

You wouldn't _need_ oxygen up to 12K but I'd feel a lot better if I had it. 
You're right, a turbocharged engine would probably be a must.  I don't know 
offhand whether the Predators are turbocharged but I'd imagine they are.  In 
any case, the chase plane must at least equal the performance of the 
'chasee'.