If we accelerate something at 9.8 m/s/s for one year, it will attain light speed near the end of the year. That's a result of there being about 30 million seconds in a year, so after a year, the velocity would be 300 million m/s--or, 300,000 km/s, more familiarly.

But an object that experiences such an acceleration will not experience a constant g, because of the distortion of its spacetime. How would that work? At one half c, gamma is what? 1/0.866? About 1.15 right? What does that do to our 9.8 m/s/s? Their rulers are shortened, so our meters are much longer, to them. Our seconds are shorter than their seconds, so the acceleration that they'd experience would be times 1.15 cubed, right? 1.5 g?