When Jake lands at the Tree of Souls, with Toruk. He has no dagger in the sheath on his chest. A few shots later, he has his dagger back. This is an impossibility as Jake lost his dagger earlier.
In the colonel's robot there is a rear-view mirror. When the robot is shown from the outside, the mirror is very close to his head. But from inside the robot, there is plenty of room around his head, and the mirror is missing.
As the dragon gunship takes off to join the formation for the finale battle it can be seen with a total of eight white missiles on eight weapon pylons; four on either side. Later on it only has four missiles on only four weapon pylons; two on either side.
When Parker Selfridge wants to explain the situation (the 'Blue Monkeys') to Jake and asks someone to operate the hologram showing the layout of the landscape he says stop at sector '12' (Hometree), but when the scene cuts to a closeup of Jake the yellow hologram readout clearly reads 'Sector 128'.
Jake is reviewing the structure of the home tree with Quaritch and Selfridge around the rotating 3-D map. When Jake makes a comment about the Na'vi studying him, his watch reads 2:19. Selfridge makes a comment about how the tree is sitting right over the richest unobtanium deposit. When the camera cuts back to Jake his watch now displays 2:53.
When the weapon is removed from Colonel Quaritch exo-skeleton's canopy by Scully, condensation is formed on the inside from a pressure change. The pressure on Pandora is lower than earth and the puff should be on the outside.
As hometree begins to topple, the long, straight vines hanging from its branches are shown to remain hanging straight down, as a heavy pendulum would. But the lightweight vines should be pulled upward, and appear to swing back as they drag in the air behind the moving treetop.
Whilst accepting it's an alien world, any large planet in such close proximity would have significant and noticeable gravitational effects - huge tides, planet-quakes, unstable meteorology and tectonic shifts. The one adjacent to Pandora appears to have no effect.
Based on the indigenous animal life on Pandora, the Na'vi should have evolved with 6 limbs and 4 eyes. The world presented has no life that resembles them at all, and yet every species that isn't a blue monkey has 4 eyes and 6 limbs.
Wheelchair users most often have a cushion on the seat of their chair so as not to get pressure sores from sitting a lot of the time. However, Jake does not have one.
The human avatars all have five fingers and toes, while the natives only have four. The reason for this is to show subtle differences in the avatars due to the mixing of human and native DNA.
When Selfridge lectures Grace in his office about the corporation's purpose on Pandora (mining 'unobtainium') he closes with the Spanish expression "Comprendo?". This is grammatically incorrect as it would mean "Do I understand?". Addressing Grace, he should have said "Comprende?" (Do you understand?). However, his language mistake shows his lack of appreciation for other cultures.
Through official canon, the atmosphere of Pandora is toxic to humans due to the presence of Hydrogen Sulfide, a very potent toxin in even small amounts.
Jake Sully is exposed to the Pandoran atmosphere for several minutes, long enough to cause complete respiratory shutdown. At this point, the effects of this exposure would not be reversed by simply donning an exopack ; unless we must presume the exopack can detect any hydrogen sulphide in the user's exhaled breath, and add suitable gases to correct the effect.
When Parker Selfridge wants to explain the situation (the 'Blue Monkeys') to Jake, he says that Hometree is on the richest Unobtanium deposit for 200 clicks in any direction. His wording suggests that other, richer deposits are farther away. It would be much easier to relocate the camp to a new deposit than it would be to move the Na'vi, but Jake makes a point to the Na'vi that more humans will come "Like a rain that never ends" So it would be expected that future camps will be set up on other deposits, and would only waste resources to relocate.
The helicopter-like aircraft makes the sound of an ordinary helicopter - this is not correct: high-speed framed propellers produce an entirely different, quite unique buzz-like, smoother noise at a higher pitch.
However, we know that they are operating in an atmosphere which is entirely different to Earth's (humans have to wear masks) and lifting an aircraft in gravity which is different to Earth's (it is stated that the humans have to work out in the low gravity), so we can't really make any comment on what these propellers should sound like. Though the characteristic whop-whop sound used is due to interaction of "air" flow of the main rotor of a helicopter like that of a 2 bladed Huey and its tail rotor. Other helicopters use 4 or 5 bladed rotors and more than two blades on the tail rotor to eliminate that characteristic sound.
When Jake's late brother, Tom, is uncovered, he's played by Sam Worthington. In the next shot of Tom being covered again it's clearly someone else.
The first part of the credits are shown over panoramic views of Pandora. Most of these shots are recycled from the movie and reversed left to right to make it a bit less obvious. One in particular was taken from Jake's ikran first flight sequence but with Jake and the ikran removed. However, the ikran's shadow passes over the rocks.
After Quaritch breaches the command center to fire at the fleeing prisoners, several personnel are seen behind him walking about normally without exopacks.
In the scene where Jake lands on Pandora for the first time, when all other personnel have gotten off the transport ship it is revealed that Jake is paraplegic. When he gets up from his seat into his wheelchair, after lifting his legs from the seat with his arms and putting them in place on the wheelchair, you can see him moving his left leg a bit backwards (without touching it).
In the nightclub scene on Earth when Jake is thrown out into the street, you can see his legs move and stiffen into a bent position (which are supposedly paralyzed) in anticipation of landing on the ground.
In the scene where Jake first meets Neytiri and is trying to thank her, he grabs her arm, however, the sound effect for grabbing her arm isn't in sync, as you can hear it a couple seconds before he does grab her arm.
Cockpits of numerous aircraft are breached without the unshielded pilots being affected by the toxic atmosphere.
When Sully gets lost on his first field trip, it seems rather odd that his massively expensive avatar body - so valuable that an untrained, inexperienced invalid soldier has been flown light years to use it - has no implanted tracking hardware to prevent exactly the kind of accidental loss he experiences.
During Jake's first excursion in his avatar, he is attacked by several species of predators, within a few hours. But every time he leaves his avatar unexpectedly (with it lying on the ground unprotected), nothing happens to it while he's gone.
During the final battle, Colonel Quaritch gives the command "Weapons Free" and subsequently orders his forces to engage all hostiles. However, "Weapons Free" means to engage any target not positively recognized as friendly. The correct command to engage all targets positively identified as hostile is "Weapons Tight".
During one of Jake's video logs, Grace can be seen working on an experiment in the background. In the process, she draws up some liquid in an Eppendorf pipette. However, in the process of transferring the liquid to its intended vessel, she inverts the pipette, which would severely damage it.
"Severely damage" is a bit strong. It would possibly be contaminated, depending on what the liquid was but decontamination is all that's required.
"Severely damage" is a bit strong. It would possibly be contaminated, depending on what the liquid was but decontamination is all that's required.
Upon hearing Jake Sully's name, Mo'at immediately refers to him (as later do the other Na'vi) as "Jakesooly". That she mispronounces the name in this particular way, however, is a bit odd; this not only means that the vowel "u" in Na'vi language is also pronounced as a variation of "oo", like it is in most human languages that use the Latin alphabet, it also implies that Mo'at knows how the name is written, as to be able to stubbornly apply her own people's pronunciation rules. The latter is possible as she is a studied woman, but it is highly unlikely that the relation of pronunciation rules between Na'vi language and English is congruent to the same relation between Earth languages.
Jake is being reborn/transferred into his permanent Na'Vi avatar body. His human body can be seen with no oxygen mask over his face. Since it takes quite sometime for Eywa to transfer souls he would have died from lack of oxygen.