Do Powell and Donovan experience relativistic time dilation, in 'Escape!'?

Question

In the Asimov short story "Escape!" (part of the Susan Calvin series), Powell and Donovan are set by US Robotics to test a spaceship with a hyperspatial drive.

They, at one point claim they have been on the ship for 5 days, whereas I believe Dr Calvin requests 48 hrs to speak to the Brain. I can't perfectly tell if these two times are coterminate or not, but if there are they only travelled at a fraction of c, not faster than it as might be claimed.

So do they experience relativistic time dilation? Or are they subject to other 'physics'?

Answer 1

No, the hyperspatial jumps were non-inertial and so Special Relativity never came into play. Also, if the ship had traveled outward at relativistic speeds and returned, it would be the travelers (Powell and Donovan) who would experience the shorter elapsed time, not the stationary observer (Calvin).

Answer 2

Those five days pass before the jump is made.

Donovan felt as haggard as he looked. "Only five days?"
"Only five days. I'm sure of it."
Donovan looked about him wretchedly. The stars through the glass were familiar but infinitely indifferent. The walls were cold to the touch; the lights, which had recently flared up again, were unfeelingly bright; the needle on the gauge pointed stubbornly to zero; and Donovan could not get rid of the taste of beans.

_{"Escape!" by Isaac Asimov (emphasis mine)}

Then they experience the jump and its peculiarities. Afterwards,

(...) Powell pointed a trembling finger at the single gauge. The needle stood stiff and proud at the hairline whose figure read 300,000 parsecs.

_{"Escape!" by Isaac Asimov}

So the five days passing is no evidence for time dilation, since it takes place before the interstellar jump.