(at around 30 mins) The plane crashes in the mountains, and appears to have stopped half way off a cliff. When people leave the plane, the plane is fully on the ground.
(at around 1h 35 mins) When Tucker helps Walker out of the water, Walker is soaking wet. We cut briefly to Qualen in the chopper, then when we cut back to Tucker and Walker, Walker is completely dry (even his hair).
(at around 29 mins) As the plane is crash-landing a rock clearly takes of the starboard wing and the rear third of the fuselage along with both engines which are behind as the forward section slides away. Seconds later as the fuselage is sliding to a stop we can hear the engines loudly "winding down" as if they were still attached.
When Stallone's character is climbing up the ice cave, you see bright blue sky and sunlight from the opening above him. Yet when he reaches the top, he must use his fists to break through the ceiling due to the thick layer of snow. (Which would have obstructed the view seen earlier).
(at around 27 mins) The cable with the suitcases disappears when the plane explodes.
In several scenes where Qualen is flying the helicopter, he is either pointing a pistol or handing keys to Jesse. Helicopters are an intense two hand operation, especially in the hover, as the aircraft is shown doing several times. There are two controls, the cyclic and the stick, and he is shown taking his hand off the cyclic, which you could not do, particularly in a hover.
(at around 1h 35 mins) When Gabe falls into the water he performs a variety of moves including removing his shirts and taunting Travers. After he emerges with help from Hal, Gabe is fine and the movie goes on. This could not happen. The temperature of the water should have put him into shock and stiffened all his limbs shortly after he fell in. Not to mention, even if Hal were to take him out, Gabe's core body temperature would have dropped to the point of a hypothermia scare.
(at around 1h 7 mins) When Frank shoos the "wolves" away from the bleeding base-jumper hanging in the tree, it is obvious due to their fluffy, curly tails that are in actuality Siberian Huskies.
When in the bat cave, he would not have to put his hand in bat poo to find out that the cave was full of bats. They would have smelled the bat poo long before they could see them. Also, the bats would not be in a winter cave like that. They would be elsewhere hibernating. Probably in the country they actually come from.
(at around 55 mins) When Gabe lights the flare, the night-vision point-of-view shot momentarily breaks up into static, like a faulty video display. This is not how night-vision works.
As Gabe is trying to prevent Sarah from falling, Frank appears to be smiling and when Sarah falls, he seems to be laughing. This is not a goof. The expressions for fear/stress and laughter are very similar. It largely depends on how an individual's face is rigged - bone structure, musculature, etc.
Despite the temperature being well below freezing, there are no visible indicators of the cold temperature, such as the characters' breath being visible, or reddened skin in the face due to the wind and cold.
(at around 1h 40 mins) Visible cables holding the crashed helicopter to the cliff.
(at around 44 mins) When Gabe opens the first suitcase and looks in it, wind blows the top bills away, revealing that the rest of the money is just blank sheets of paper.
(at around 56 mins) The guy Gabe is fighting as they slide down the mountain falls off the cliff. At the end of his fall, the stunt airbag he lands on can be seen.
In some scenes, the snow is obviously fake.
The Landrover Defender driven by Gabe was obviously chosen as a macho symbol of exotic adventure but the package is very odd. This model has a double roof - a layer of sheet metal suspended above the actual roof. Its function is to catch the heat of the sun and allow it to be dissipated by the air moving underneath. It is only used in regions with conditions of excessive heat, such as on the equator. Beyond this, the suspension of this vehicle tends to be very hard and the seats have very little padding, making it particularly unsuited for mountain roads. For Gabe the mountain climber to own one is very odd.
Every man is clean shaven throughout the entirety of the movie, including most notably those who spent the night on the mountain without even so much as gear or (presumably) razors.
If the frequency code changes every 15 seconds, how will Travers know what numbers to enter, unless if he has his personal code.
When Gabe is holding Kynette to impale him on the stalactite, Kynette doesn't stab him, despite having a knife and having plenty of chance to.
(at around 1h 35 mins) Gabe talks to Qualen on the radio while waving to him with the arm holding the radio.
At 1 hour, 30 minutes, Travers gun makes a cocking sound even though he only has one hand on it and his opposite hand is holding the tracking device.
(at around 1h 20 mins) There is a camera shadow on Frank as he approaches Kristel lying in the snow.
At about 56 minutes when Stallone and a bad guy fight and slide off the edge of a cliff - the bad guy falls to his death. Stallone halts his own fall with an ice axe, his boots hit the cliff and you can see the "rock" rebound.
(at around 1h 5 mins) Tropical fruit bats do not hibernate in the Rocky Mountains.
This film takes place in Colorado, in the Rocky Mountains. When the villains use night vision, it shows their elevation as somewhere in the 3,000 ft range. However, even the lowest point in the Colorado Rocky Mountains is well above 3,000 feet.
(at around 12 mins) The money was made in the Denver Mint, but the Denver Mint only makes coins. Banknotes are printed by the Bureau of Printing and Engraving, located either in Washington, DC or Fort Worth, Texas.
The villains' night vision displays an initial elevation of 5081m, which is 16667ft. The film is set in Rocky Mountain National Park, which has a maximum elevation of 14,259ft or 4346m. One can assume the measurement on the night vision is in meters because the temperature gauge is in Celsius. Even if measured in feet the lowest elevation found in RMNP is 7,630.
Without any way to locate the beacon, with very little climbing equipment, in heavy snow, Gabe and Jessie and able to find the second case of money before Hal and the gang.
The choice to kill Gabe after he finds the first case and before he returns with it is very illogical as the villains had no way to retrieve the case easily and the only control they could exert to stop him fleeing was the hostage. Once only one climber remained it would be much easier to escape in similar situations.
Gabe and Hal reach the plane by climbing up a cliff in a snowstorm, but later events show the site is accessible by walking.
Stallone's character is seen wearing a wedding band in earlier scenes yet in the film he is not married. This is confirmed when he states that he's came back for Jessie, clearly his love interest but not his wife.
When Qualen captures Gabe and Hal, he asks where the helicopter is. Hal replies: "It can't fly in this weather". It's later revealed that Qualen is also a helicopter pilot therefore it's a stupid question for him to ask considering that the character is an experienced and well motivated psychopath capable of thinking precise details.
Hal (an experienced mountaineer) is ordered to tie a rope to Gabe before his climb towards the first case. The most natural place to attach the rope would be Gabe's harness, however Hal ties it around Gabe's foot.
(at around 23 mins) As the jets are flying in close formation, the DC-9 pilot is told to "slow to 150 knots" and to "descend to flight level 140". Both of these phrases are incorrect. In the United States airspace system, the term Flight Level is only used at 18,000 feet and above - flight level is a measure of hundreds of feet (Flight Level 310 = 31,000 feet above sea level). There is no Flight Level 140; it would be expressed as 14,000 feet.
The pilot of the transport plane says he's at 250 knots and flight level 2109. If that flight level even existed, that would indicate an altitude of 210,900 feet which is ludicrous, especially since moments later they claim to be at flight level 150, which again doesn't exist. Regardless 15,000 feet couldn't be achieved even in free fall from 210,900 feet in the time elapsed, never mind "level flight."