a Haertel Complex story
Common Time
by James Blish
Spaceman Garrard is the third pilot to attempt the trip to the binary star system of
Alpha Centauri using the FTL drive invented by Dolph Haertel (the
next Einstein!) The Haertel Complex stories provide little in the
way of actual time travel, but this one does have minor relativistic
time dilation and more significant differing time rates.
— Michael Main
Figuring backward brought him quickly to the equivalence he wanted: one second in ship
time was two hours in Garrard time.
“Common Time” by James Blish, in Shadow of Tomorrow,
edited by Frederik Pohl (Permabooks, July 1953).