When the merc walks from the van to the missile launcher, he is not wearing his glasses.
There is no threaded bracket behind/below the ventilator dome for attaching the small nut that Steve causes to break off; also, that tiny fastener would never hold that huge heavy vent assembly in place in a moderate wind.
Nothing drops out of the sky when the supposed missile strikes the ravine and detonates in a fireball; obviously just a small buried explosive charge that was remotely set off to produce a big impressive-looking plume of flame and smoke.
The van's tire is just sitting in undisturbed gravel and its tread and sidewall are clean, so obviously the surrounding gravel was just heaped up around the tire and smoothed off prior to the shot's being filmed; the gravel is not all thrown up and soiling the tire the way it would be if the van had become mired.
The merc says that they will perform a lot more sensor drops and that the military official will warn them about it a lot more times, yet just a few minutes earlier, the official had said that he had issued his final warning and that the merc's plane would not be permitted to fly there anymore if there was another violation.
Leslie writes "Love Joy Buttes" on her painting of the condor, yet Steve reads it off as "Love Joy Butte".
Steve does not wear his safety harness during his next-to-last sailplane flight.
After sailing together with Steve's plane, Leslie does not turn her plane around after landing, so she could not have immediately gotten towed airborne again, since she'd have been facing "backwards" towards the head of the runway, rather than positioned to face down it toward the far end.