The following weapons appear in the anime Planetes:
AKS-74U
Several of the El Tanikans at the research facility in "Boundary Line" (Episode 11) can be seen using rifles resembling AKS-74Us, with a solid stock fitted and missing the top of the handguard.
A pair of guards at the research facility with their AKS-74Us.
Whilst the soldier is talking on the comm, the distinctive muzzle brake of the AKS-74U can be seen.
M16A2
M16A2s can be seen being used by third world rebels and INTO forces alike.
One of the El Tanikan rebels in "Boundary Line" (Episode 11) firing an M16A2.
A group of INTO soldiers armed with M16A2s in "Tandem Mirror" (Episode 21).
FN Five-seveN
During their attack on the Von Braun, the Space Defence Front (SDF) terrorists carry pistols based on an FN Five-seveN fitted with a torch and laser.
FN Five-seveN USG - 5.7x28mm
Claire pointing her pistol at Fee in "Debris Cluster" (Episode 23).
Claire floating along a corridor with her pistol at the ready as the SDF board the
Von Braun.
Hachimaki reaching for a dropped terrorist pistol.
Hakim drops his pistol as he is attacked by Hachimaki in "Love" (Episode 24).
Hachimaki turns Hakim's own pistol on him.
A closeup of the side of the pistol showing the controls, which match that of the FN Five-seveN apart from the manual safety switch is reversed.
Hachimaki trying to fire the empty pistol in "The Lost" (Episode 25).
Heckler & Koch Mark 23
H&K Mk 23 Mod 0 - .45 ACP
FN P90