In the aftermath of the German Stukas' raid on the beach, there is no sand in Tommy's hair after he stands up, even though a nearby explosion had covered him with sand just moments prior.
The beach section of the movie takes place over a week, whereas the air section of the movie takes place over an hour. The craters shown earlier on the beach would have been filled in by sand when the tide came in over the days leading up to the pilot having to land his spitfire, so it wouldn't necessarily still have the craters when this scene happened.
Later in the film, Winant now has the correct two pips and crown of a colonel.
Before ditching his Spitfire on the desolated beach of Dunkirk, errors are made with regard to the altitude of Tom Hardy's plane when switching between shots.
Near the end when Farrier runs out of gas in his plane he still manages to shoot down an enemy plane. He then does a flyby of the beach while we see several hundred or thousands of soldiers cheering. By the time he coasts down and lands on the beach, which would only take a matter of seconds, a minute or two if we're being generous, he is the only one left.
None of the civilian buildings in Dunkirk have any damage. Between ground fighting and aerial bombardment, much of the town was devastated before the evacuation started. Filming on location in the actual city of Dunkirk after its wartime damage had all but disappeared, this was inevitable as the filmmakers certainly could not 'return' the city to its ruined World War II condition.
The Mk 1 Spitfires portrayed had a total fuel capacity of 85 imperial gallons. This was held in two tanks - one above the other. The top tank emptied into the bottom tank till it was used up. The fuel gauge the pilots are checking was only capable of measuring the bottom tank which held 37 gallons. Therefore it would not be possible for the pilots to determine they had 50 galls of fuel remaining.
Once the Dutch fishing boat floats on water, the film presents that bullets penetrate the ship's hull even at a depth where water leakage was uncontrollable. While grounded, it is likely that bullets would penetrate ship's hull. But once floating, it is unlikely that the common German rounds would penetrate the hull because of the water resistance.
Before a ditching or forced landing, a pilot would have been trained to open the canopy to prevent it from jamming because of the impact forces (incidentally, in many cases, pilots taking off from aircraft carriers even left the canopy open just in case they ditched immediately after lifting off). Not only does this not happen in the movie but, in one case, the pilot even opens the canopy and, inexplicably, closes it back before touching down (actually leaves it ajar one inch or two). Predictably, in the second case, the canopy jams, nearly causing the pilot to drown.
Further, in this second case, the pilot waves through the opening. However, there would not have been enough of an opening for him to squeeze his forearm through.
The Spitfire pilots expend over 70 seconds of ammunition during the course of their one hour mission. In 1940, pilots would need to have been far more frugal: Spitfires would need to rearm after only 15-20 seconds.
During the movie the beach is a cratered landscape, caused by continuous bombing. In the end sequence, when Farrier floats over the beach trying to land, the surface is completely smooth. However, many areas of the Dunkirk beaches were relatively flat and made of hard-packed sand. It has been recorded that pilots found it was an ideal landing strip, and some RAF aircraft did land on the beaches.
Early on, one overhears an officer state that a stretcher takes the place of seven men standing on the ship. This might seem an exaggeration until the length of a medical stretcher (6 to 9 feet) is taken into account.
As the Spitfire glides over the Dunkirk Beach a number of the houses in the background were definitely modern, some with aluminum facades. The architecture for many of the homes appears to be late 20th century.
Mr. Dawson identifies aircraft approaching him from behind as Supermarine Spitfires by the distinctive sound of their Rolls-Royce Merlin engines. However, there were many other aircraft using that engine at that time, including another common Royal Air Force fighter aircraft, the Hawker Hurricane. Thus, the engine sounds alone would not have necessarily allowed Mr. Dawson to so easily identify Spitfires from other aircraft.
Many of the shots of Farrier in the Spitfire cockpit were shot in a different two seat prop aircraft (visible in a YouTube video - search Dunkirk Lee on Solent) which was been adapted to resemble the rear of a Spitfire and its distinctive tail. The revealing element is the extended tail wheel, which is longer than that on the Spitfire.
The "little ship," the Moonstone, and its crew - including George Mills, 17 - is openly based at Weymouth, Dorset. They return to Dorset, passing the white cliffs. George Mills is from Dorset. Yet, the local newspaper - the "Weymouth Gazette" - has a front page tribute to George Mills that states he is "from Ramsgate." The seaside town of Ramsgate is in Kent, near Dover, about 150 miles east of Weymouth.
In some of the transport ships scenes and one or two scenes on the pier at 'The Mole' the end of the barrel on several rifles can be seen to be solid. Holes at the end of the barrel bore should be seen.
One of the shots when soldiers are ducking on the mole is used twice (look for the soldier in the blanket). Timestamps: 0:26:34 & 1:28:31.
27th minute the German planes strafe the escaping English soldiers stranded on the dock. But they strafe and bomb width-wise across the dock, rather than lengthwise, which would be more efficient.
As the Spitfire's wheels finally touch the beach, the sun can be seen setting forward and left of the Spit's direction of travel. The sun sets in Dunkirk at the end of May at about 308 degrees. This implies that the plane is travelling almost due north. There are no north/south oriented beaches in Dunkirk.
The Luftwaffe did not start painting fighter aircraft nose cones yellow until later in 1940. However Christopher Nolan has admitted this was done deliberately to make the German aircraft easier to identify by the audience.
The railway carriages in the final scenes date from the 1950s and have seat patterns from the 1980s.
The standard ammunition load for a British Fighter in early World War 2 was the Caliber .303 round with eight (*) wing mounted machine guns. The rounds were in arranged with ball, tracer, incendiary, and armor piercing projectiles in-dispersed in the ammunition loading. Of special note was the B4/B4Z incendiary round that had soldered holes (over a phosphorus core) in the projectile that when fired melted from the friction of the projectile leaving the barrel which left a visible smoke trail as the bullet flew through the air. This is evident in the actual combat footage used in earlier films ("Battle of Britain") involving Spitifres or Hurricanes where British aircraft fired their machine guns, a line of spiraling smoke trails reach out towards their target. This type of ammunition was an aid to marksmanship. Later in the war the British moved to use tracer ammunition which leaves a bright colored trace in the air.
There are two instances when the German Heinkel He-111 comes under attack by a British Supermarine Spitfire. Both times, the Heinkel sounds like it fires cannons in its defense. The Heinkel He-111 H-3 variant, the one used during the time period, did not have cannons as defensive armament. It was armed with MG 17 Machine Guns as defensive armament.
During the scenes shot in Weymouth on a couple of occasions, the top of the Weymouth "Sealife Tower" is visible, which was built circa 2012.
As the soldiers abandon the Dutch trawler, the planes fly overhead. They are all propeller-driven (as were all operationally deployed aircraft at that point in the war). However the English subtitling for the scene says, "Jet engine roaring."
As Tommy and Gibson are racing the wounded soldier on the stretcher to the ship early in the film, tire marks from the camera rig are clearly visible in the sand on both sides of the frame.
In the 89th minute as the fighter pilot is preparing to land on the beach, the reflection of something appears on the near side of his goggles, possibly another aircraft.
Mr. Dawson's 'Moonstone' is portrayed as returning from Dunkirk to Weymouth in Dorset. That's 250 miles - which at a cruising speed of 7 knots would take more than 2 days flat out. The real small boats went to places such as Ramsgate.
Photographs and video footage taken of the beaches at Dunkirk after the evacuation show the beaches being littered with abandoned vehicles, equipment, wreckage, and bodies. The beaches in the film remain relatively clean throughout the film.
When pinpointing the location of the "package" the commander points to a map and states that he is at 51 degrees north and 37 degrees east. 37 degrees east runs through Israel. Dunkirk is at 51N 2E.
Even though the canopy should have been open for the ditching, all Spitfires have a crowbar stowed in the cockpit door (readily available to the pilot) for such emergencies.
In the grounded fishing boat, the soldiers have a lengthy discussion who to sacrifice in order to aweigh. During the argument several cubic meters of water floods though the bullet holes, weighing more than all men combined and making the debate futile.
On the beach, a British soldier salutes an officer while he is not wearing any head wear. This would never happen in the British services. If he wasn't wearing a hat or similar, he would have simply stood to attention to address the officer.
The Royal Navy Officers conducting the boat requisitions early in the film are wearing the incorrect cap badges. Instead of the cap badge worn by officers to signify a commission, they wear that of a Petty Officer, a non-commissioned rank.
The film focuses on some soldiers jumping the queue, when one of the noted characteristics of the Dunkirk evacuation is how extremely well disciplined and ordered the soldiers were in queuing for the ships.
At the start, Tommy and his comrades try to outrun German rifle bullets - travelling at 2,500 feet/second - instead of dodging sideways into doorways and windows.