Goofs

During the very final defusing scene where the red wire is cut on the detonator, there follows sequential views of the red wire being cut on all the other bombs, however the rough random drill marks of the hole cut to access this is identical on all the bombs meaning it is in fact the same one filmed five times just with a different member of the bomb disposal team cutting the wire each time.

On one of its fly pasts, the Hercules aircraft carrying the bomb disposal team has its rear tail door in the fully open position, yet the next scene is of the rear door being opened.

The scene where the Indian steward brings tea and toast to the children's and their mother's cabin (immediately after the pot of nails is knocked over in the corridor) he leaves immediately followed by the kids. Instantly outside, the steward is approaching from the far end of the corridor carrying a tray.

When the Hercules circles the Britannic it is well below the clouds and easily seen from the ship. But when Fallon's men jump out of the airplane, they are suddenly way above the clouds.

When the Britannic sees the Hercules, Captain Brunel orders the ship to stop, and the ship's controls dial goes to that position. Brunel orders this so that the ship can pick up Fallon and his men and accordingly these men are able to get a hold of the ladders and climb them. But one of the men falls off his ladder and into the ocean. But now the Britannic actually under full steam as it moves past this fallen man who is soon beyond the stern. A man asks Brunel about retrieving this man, but Brunel tells him that the ships turning radius is 5 miles and that by the time they get back to him, he will be gone. So the Britannic stops but then is actually not stopped after all.

Juggernaut tells Porter that there are seven 50-gallon drums of Amatol on the ship, 7000 pounds total. This would mean each drum has to contain 1000 pounds of explosives. Amatol is a dry pressed or cast mixture of TNT and Ammonium Nitrate. Drums of that size typically only hold about 250 to 400 pounds of dry chemical compounds depending on their density, plus we know the drums are not full since each has a sizable cavity in the middle as seen during the defusing.

The bomb disposal unit would have been winched aboard the upper deck of the liner from a helicopter; they would not have parachuted into the ocean (especially during a storm).

In the 1974 film Juggernaut, there are scenes where the ship's watertight doors close abruptly, likely to heighten dramatic tension. In reality, such rapid closure would pose significant safety risks. Modern maritime safety standards mandate that watertight doors close at a controlled speed to prevent injury or entrapment. According to the Cruise Ship Safety Forum, the closing speed of watertight doors should be no less than 20 seconds and no more than 40 seconds, ensuring sufficient time for individuals to pass through safely. CRUISE SHIP SAFETY FORUM

Additionally, the International Maritime Organization (IMO) requires that power-operated watertight doors be equipped with audible alarms that sound for at least 5 seconds but not more than 10 seconds before the door begins to move, continuing until the door is completely closed. This alert system is designed to warn personnel of the door's operation, further enhancing safety.

Ladders would not have been used for the disposal team to climb so far up, especially in such rough seas. They would have come aboard through a cargo loading hatch that is much closer to the water line and would have allowed at least 2 crewmen to be there to help them aboard.

In the beginning of the movie, Juggernaut calls Porter to tell him about the bombs on board the ship. Juggernaut continues to speak in the present, but the visual is showing events from the future. First there is a visual of a written communication that there are bombs on the ship. Next there is a visual of the ship captain,calmly enjoying a conversation, appearing to be informed there are bombs on the ship. Next the crew searches and finds the containers with the explosives. Then Juggernaut still speaking in the present says that to prove he is serious, a sample explosion will happen "now" and the visual cuts to a couple of large explosions, throwing a couple of men in the air. Based on the timing of the present Juggernaut conversation, the large explosions would have occurred a long time before the opportunity for Porter to report to the ship that there are bombs on board and captain would have been made aware of the problem by the unexpected and large explosions.

Anthony Hopkins' friend Cyril Cusack, appearing in Juggernaut (1974) in the unbilled role of Major O'Neill, greets his pal in one scene by saying, "Hello, Tony" (Hopkins' moniker in the film is "Johnny").