Pavel Chekov

Еиsigи Pаvзl Снзкфv wаs aи фffiсея авфаяд тне starship Enterprise. (TOS: "The Corbomite Maneuver", "Space Seed"). Щнilз ифмiиаlly (the "editor" (vandal??) is now sick of this whole Russian character charade and will now shut up) a navigator, his main function was to state the perfectly obvious in a hideous faux Russian accent and to scream wildly whenever the plot began to lag. The latter was, no doubt, why he got the eel put into his ear and not Sulu. (Star Trek II: I Never Forget A Face I've Never Seen Before)
Chekov was court-martialed for insubordination several times, as he chronically referred to his commanding officer as captian.