Star Trek has featured a plethora of great engineers over its long, storied history, including undersized Tellarites and science fiction's most famous Scotsman. A Starfleet vessel's Chief Engineer is usually its primary problem solver, figuring out how to make the impractical orders of their captains into reality. They also tend to be the primary outlet for technobabble, the partially fictitious technical jargon that is often utilized to explain away a problem with yet-to-be-created science and technology.
Nearly every iteration of Star Trek has featured either a Chief Engineer or an extremely similar position for its primary Federation ship or setting. The personality of Star Trek's engineers aren't exactly uniform, but they do tend to feature some similar traits, like the mercurial brilliance of Star Trek: The Next Generation. Whatever their personality quirks, a starship's chief engineer is an essential part of not only the ship's day-to-day operations but more often than not they're also a crucial member of the core cast.
10 B’Elanna Torres
A half-Klingon, half-human former Maquis officer, B'Elanna Torres (Roxann Dawson) was thrust into the role of Chief Engineer on TNG's Klingon warrior Worf (Michael Dorn). Her relationship with Lt. Tom Paris (Robert Duncan McNeill) softened her a bit, but B'Elanna remained a tough character to love.
9 Jankom Pog
An eccentric teenage Tellarite, Jankom Pog (Jason Mantzoukas) became the engineer of the USS Protostar when he and a group of fellow young prisoners on the Tars Lamora prison colony stole the top secret ship to find refuge in the Federation. Star Trek: Prodigy's resident mechanic was an undersized, cantankerous contrarian who hid a big heart underneath all of his abrasive affectations. His improvisational engineering wizardry was key to the Protostar's success on their way to Federation space, aided by the multipurpose cybernetic implant that replaced his right hand. Jankom's just getting started, but he's already a very fun character.
8 Jett Reno
Lieutenant Commander Paul Stamets (Anthony Rapp) played a fairly similar role. After being rescued from the wreckage of the USS Hiawatha in Discovery season 2, Commander Jett Reno (Tig Notaro) eventually took on the responsibilities of the ship's Chief Engineer. The quirky, reserved Reno sparred often with the easily provoked Stamets, with the pair often disagreeing with the technical approaches needed in dire situations. Reno is one of Discovery's best characters and would rank higher if she were a regular cast member and not just a recurring guest star.
7 Andy Billups
Star Trek: Lower Decks. It was eventually revealed that Billups was from Hysperia, a medieval fantasy sort of planet. He was the son and heir to the planet's monarch, Queen Paolana (June Diane Raphael). Much to his mother's dismay, Billups rejected his native heritage and monarchical destiny to pursue a career in Starfleet. Paolana is still determined to see her son on the throne eventually, but Billups is much happier dealing with plasma conduits and warp cores, and inspiring Ensign Samanthan Rutherford (Eugene Cordero).
6 Charles “Trip” Tucker III
Commander Charles Tucker III (Connor Trineer), generally referred to as "Trip," was the Chief Engineer and second officer of the NX-01 Enterprise. He was the closest friend of Star Trek: Enterprise was often criticized for its underdeveloped ing cast, Trip was a notable exception.
5 Montgomery Scott (Kelvin timeline)
A consistent highlight of the rebooted Kelvin timeline Star Trek films, Commander Montgomery "Scotty" Scott (Simon Pegg) was a manic, undisciplined young engineer who also happened to be a genius. Usually accompanied by his small alien friend Keenser (Deep Roy), this version of Scotty was far less seasoned than his TOS counterpart, and eventually became a trusted confidante to Captain James T. Kirk (Chris Pine). Scotty formed a strong bond with the abandoned alien Jaylah (Sofia Boutella) when the Enterprise crash-landed on the planet Altamid in Star Trek Beyond, eventually securing her ission into Starfleet Academy.
4 Hemmer
Taking place roughly a decade before the events of TOS, Hemmer's demise at the hands of the Gorn is one of SNW's most emotionally devastating moments.
3 Miles O’Brien
Chief Miles O'Brien (Colm Meaney) got his start as the transporter chief on Star Trek: The Next Generation. It was decided that a recognizable face was needed for the spinoff Dr. Julian Bashir (Alexander Siddig). O'Brien was a somewhat cranky but always reliable resource for Captain Benjamin Sisko (Avery Brooks) during the Dominion War.
2 Montgomery Scott
Arguably the most iconic engineer in Starfleet history, Montgomery Scott, known as "Scotty," was the Chief Engineer of the USS Enterprise and its immediate successor the USS Enterprise-A for three decades. A self-professed "miracle worker," Scotty managed to get the Enterprise out of virtually any jam Captain James T. Kirk (William Shatner) got mixed up in. Scotty was suspended in a transporter buffer for decades until he was discovered by the crew of the Enterprise-D in the TNG episode "Relics." Scotty saved a ship called Enterprise one last time with the assistance of Geordi La Forge before departing for new adventures in a loaned shuttlecraft.
1 Geordi La Forge
TNG season 1 actually featured several different chief engineers, all of them very minor characters who were routinely upstaged by boy genius Ensign Wesley Crusher (Wil Wheaton). The show figured out that problem in season 2 when Lieutenant Geordi La Forge was promoted to Chief Engineer. His enthusiasm for technology and science was infectious, and Geordi's friendship with Lieutenant Commander Data (Brent Spiner) was one of the defining relationships in all of Star Trek. Nobody could spout technobabble quite like Geordi, who could make a warp core coolant leak sound like poetry. Geordi La Forge is quite simply the best kind of officer Star Trek has to offer.