That (the IPA designations) could, and probably is, helpful for breaking down sounds on paper but taking that /t/ from what is a manual of sorts and dropping it into a foreign transliteration is the opposite of helpful.

Everybody expect the French won't have any problem reading out without stumbling Chkalov or Chmil. Supplying the /t/ is a copout to please the French and, as a bonus, to piss of the Russians (especially the Chekalovs ones).