I would not do that. I'm not sure what sort of checks they do on the airplane, but I definitely wouldn't get it checked as luggage (have you seen the brutal way that they treat luggage?) and I would be extremely weary about having an external hard drive go through a checkpoint. If anything, let it go on the belt where they x-ray carryons because taking it through the metal detectors WILL wipe a hard drive.
How would taking it through the check-in belt, like with a laptop, be any worse for it? Is it because the laptop's hard drive is better protected? (Serious question).
I def. wouldn't check it, not because of the way luggage is treated but because of thw more powerful XRays they use back there. That's why they tell you not to put your film in your checked bags.
Good morning, son
In twenty years from now
Maybe we'll both sit down and have a few beers
And I can tell you 'bout today
And how I picked you up and everything changed
It was pain
Sunny days and rain
I knew you'd feel the same things...