The 14 Dumbest Things In Star Trek IV: The Voyage Home
10. The Space Tugs Stop When They Lose Power
Even as the Excelsior and other starships in Spacedock sit on their figurative hands and are disabled, we see the engines go dead on a pair of the “tugboat” shuttles (ILM’s Bill George confirmed that’s what they are), and they come to a halt.
Huh?
These are not motorboats on a lake whose engines die and their momentum bleeds off pushing against the water. These are spaceships in a near vacuum. Even if the preposterous airship hangar was pressurized, which there’s no evidence of, their momentum should have carried them in straight lines until they smashed into a Spacedock wall or one of those disabled starships.
Which makes you wonder: if the Probe disrupts all the power sources employed by Starfleet and on Earth, what exactly happened to everything else when it pulled into orbit? It clearly didn’t kill all the power because at Starfleet Command we see dimmed lights and scrambled but operating screens, so what level of power was affected?
As the Bird of Prey gets knocked out immediately upon popping back to the 23rd century, and those Spacedock tugs got insta-offed, we have to assume every powered vehicle and delivery drone in the air above Earth plummeted and crashed. One hopes Earth's government grounded everything before this could happen… but given Starfleet’s wait-til-after-the-last-minute incompetence this is unlikely.
Starfleet is dumb.