After Rocky leaves, there is another joke at Mel Gibson's expense. Bunty says, I don't even think he was American, a reference to the common misconception that Gibson is actually Australian. (Although he was born in the USA and didn't move to Australia until he was 12, the belief persists, especially in the UK, that he's Australian.)
The filmmakers were nervous about showing Rocky and Ginger kissing, fearing the sight of two chickens touching beaks would look too awkward. This led to the running gag of their being interrupted every time they are about to kiss (by the sound of the pie machine, by Ginger slapping Rocky, by the gravy explosion, etc.). When the kiss finally comes, it is staged so that the actual contact of "lips" is hidden.
There was a major push to get the film nominated for Best Picture at the Academy Awards. The failure to get the nomination, and the popularity of the film among Academy members led to the inclusion of Best Animated Feature for the next Academy Awards (2002), which was won by fellow Dreamworks film Shrek (2001).
The characters' bodies were made of silicone with latex covering, while the heads and hands (or wings) were plasticene. All the chicken characters have collars and ruffles to hide the disparity between the modeling clay heads and wings and the latex-covered bodies.
One reference to Indiana Jones in the pie machine sequence that was never used had Rocky come face to face with a chicken skeleton inside the machine, as Indy does in Raiders of the Lost Ark (1981). Rocky would then have said, "They bought a used machine. How cheap is that?"
John Sharian's part was a lot longer, but cut to the point that only a single line of his was left: "Sure". It was a costly cut, since Nick Park arranged for him to be flown from America just to do the part.
In the scene where Rocky is tuning in the radio, one of the short bursts of music heard is from the opening theme to The Archers, a long-running British drama series on BBC Radio 4 (An everyday story of country folk). The Archers began in 1950, and is still broadcast regularly to this day (2015).
During the screwball teaching the hens to fly sequence, Mac, the Scottish chicken is tossed into the air exactly like a caber in the Highland Games. And, in fact, when she lands on her head and falls facing exactly away from her tosser, this would achieve the maximum possible score for that event.
Scenes deleted from the finished film included Fowler being an alcoholic, a chicken eaten by the watchdogs in an escape attempt, Rocky's sole escape from the farm by hiding in the egg bucket, and a more elaborate climax. It involved Mr Tweedy's Mini, a truck, a combine harvester, Rocky and Ginger jumping over hedges on a trike like Steve McQueen in The Great Escape (1963) before going over a cliff, Mrs Tweedy falling in mud and the harvester encasing her in a bale of hay, with Mr Tweedy gloating "Right there's going to be some changes around here." Then the albatross breaks up and the chickens fly by themselves into the sunset. When they land they dance the "Funky Chicken" in celebration.
It took a week to create 3-4 chickens. Each one was designed with an armature underneath, like a skeleton, and rods were used whenever a chicken ran or flew. The puppets were then manipulated and photographed 24 times for every second of film. Several puppets were produced because plasticine isn't too durable. So silicon was used too because it is more durable and saved time on making more puppets. There were 100 individual stages in order to create a chicken.
Fowler's "military service" is not entirely unprecedented. During an actuality recording made under fire during the March 24, 1944 invasion of the Marshall Islands by the Firth Amphibian Corps, correspondent Fred Welker reported on the sudden appearance of a chicken in the midst of the gunfire, which broke the tension. Walker then reported on the inexplicable appearance of chickens during previous invasions, suggesting (in jest) that the USO must be sending them.
When Rocky first appears on the farm, Fowler denounces him (and all "Yanks") by calling him "overpaid, oversexed, and over here!". This was a common gripe about US service members expressed by British (and in the Pacific Theater, Australian) troops and civilians during World War II (it has since passed into the vernacular as an expression of mild resentment towards America). The American retort was that their allies were "underpaid, undersexed, and under Eisenhower!". In the same rant, Fowler also claims that Yanks are late for every war. The USA entered WWI in 1917 and WWII in (December) 1941, roughly three years after the British had started fighting in each war.
Originally, the filmmakers had planned to have sparrows ridicule the chickens' attempts at flight. Rather than spend time and money on characters that would be on screen for only a brief time, they used Nick and Fetcher instead.
The pie machine was meant to show the threat of mechanization. 50 people worked on its design. The cogs in the machine were silver spray painted to make them look metallic (they were made of polyurethane), and then scrubbed down to take some of the shine off. Finally they rubbed the (plywood) interior with lead grate polish to give it the look and feel of age and use. The machine even had a plaque to give it a further touch of authenticity.
Some ideas in the film derive from when Nick Park kept chickens as pets when he was a boy, e.g. naming Rocky "the Lone Free Ranger." Also, when he was a teenager, Park worked in a chicken packing factory, and his days in the slaughterhouse gave him the idea for the pie machine, like Ginger hung upside down from her legs.
Many sequences were modeled after 1963's "The Great Escape". When Ginger is digging the tunnel she is shown on a small trolley being pulled through the tunnel like the character played by 'Charles Bronson'. When she is locked up she bounces a ball against the wall like the character played by Steve McQueen. Even the music is similar to the "Escape" theme.
The scene with Rocky and Ginger on the roof took five months to animate. The animators carved semicircular chunks into the roof and placed Rocky and Ginger into the hollows to give the illusion of sitting-down. The dialogue was short but the stage directions included tiny details, which is why the scene took so long to animate.
"Hut 17" is a reference to the WWII P.O.W. film Stalag 17 (1953), directed by Billy Wilder. Rocky also says "I've met a lot of hard boiled eggs in my time, but you're twenty minutes," a line from Wilder's film previous to Stalag 17, Ace in the Hole (1951).
The bumps on each chicken were nicknamed "fluffles" by Aardman. Bunty's character, for instance, has 3077 of them. They avoided feathers because they're tough to animate. And the beaks were held in place with a locator.
While the normal frame rate for a motion picture is twenty-four frames per second, and all the Aardman Animations shorts had been shot accordingly, this film was shot at only twenty frames a second to save on time and money.
The light bulb in Hut 17 was real so it appeared in scale with the rest of the set. Also, the doors and windows in Hut 17 worked on real hinges. The ceiling had irregular holes cut into it to create a desired light effect. The disco ball also made real reflections
Three characters went on to be in the Harry Potter series, Bunty, (Imelda Staunton) as Dolores Umbridge, Nick the rat (Timothy Spall) as Peter Pettigrew, and Mrs. Tweedy, (Miranda Richardson) as Rita Skeeter.
Originally Rocky had a wattle, but this was later removed. Another early idea that was dropped was the chickens learn to fly at the climax just by believing it. Another was the chickens once escaped from a nice farm, and when they misbehaved, they were sent to Tweedy's Farm as a punishment.
There is a possible reference to Matt Groening's The Simpsons; when Rocky falls in the pie dough and proclaims "dough" in an annoyed manner, which is Phonetically similar to Homer Simpson's catchphrase "D'oh". A year before the release of the movie, Mel Gibson guest starred on The Simpsons episode "Beyond the Blunderdome" as himself.
Although Fowler claims to be a member of No. 644 Squadron RAF, the "crate" on the postcard he shows to Ginger is actually an Armstrong Whitworth A.W.38 Whitley, a medium bomber used by the Royal Air Force from 1937-1942 (saw limited use until 1946). No. 644 Squadron RAF actually flew the Handley Page Halifax.