!!FridgeLogic
* In "Abu Dhabi", Carolyn is trying to cut any cost she can as much as she can. The cargo hold heating is very expensive, as Carolyn has previously pointed out to Martin. Why doesn't Carolyn make Arthur put the cat in the ''heated'' cabin with him?
** Possibly Carolyn doesn't trust Arthur to keep a cat alive. And it can't go in the cockpit, since we learn in "Ottery St. Mary" that Martin is such a stickler he won't even allow a ''hypothetical'' otter up there.
* None of the three Birling Day episodes actually end with Douglas successfully getting the Talisker off the plane: in "Edinburgh" Martin unwittingly gives Birling the bottle which Douglas has hidden it in, in "Paris" Douglas gives it up for a thousand-pound reward from Birling and in "Timbuktu" Carolyn is attempting to steal it from him, but Birling is never actually given the whisky. So what happens when Douglas does actually get the whisky off the plane, as apparently happens in every other year? Mr Birling seems completely unaware that such a thing happens in "Paris".
** According to Douglas in "Paris", he sells it.
*** Yes, but the question was why doesn't Mr Birling notice, as in "Paris" he seems to be unaware of the whisky theft ("How many mid-air whisky thefts do you deal with?") and he presumably wouldn't keep going with MJN if the whisky was stolen before he could get it each year (in "Timbuktu" he says he only uses MJN because they're the only company that can get Talisker 25 in).
*** Likely because much like the Russian yacht tycoon in Molokai his palate is well and truly shot once in the air. Plus the placebo effect regarding the cheap whiskey Douglas will inevitably give him will kick in long enough to get him drunk to past caring.
** Moreover, why do they act like Martin lost the bet to Carolyn in "Paris"? They convinced Carolyn it hadn't been stolen and Mr Birling got his whiskey and Carolyn doesn't talk to him anyway. Martin should be due his reward.
*** Martin would never get away with breaking the rules and lying to Carolyn. See "Timbuktu" for what happens when he tries to mastermind the scheme.
*** Confirmed by WordOfGod on John Finnemore's blog, as "Martin is too decent, Douglas too boastful and Arthur too incapable of lying" for Carolyn not to work out the truth pretty quickly.
** Why is Douglas so desperate to steal ''opened'' bottles of Talisker? There isn't much of a market for unsealed whisky, and the nail varnish trick probably wouldn't fool a serious buyer. It seems like a lot of trouble to go through for limited resale potential.
*** 'Going to a lot of trouble for no better reason than being a smart arse' is pretty much Douglas's middle name though. Like the smuggling thing - he seems less interested in monetary gain than a compulsive need to cheat and win. He also has the motivation until “Edinburgh” of wanting to disguise his teetotal-ness. He might just sell the bottles to an acquaintance to make a few quid too.
* In "Zurich", Theresa tells Martin that Liechtenstein doesn't have an airport. If that's true, where was GERTI landed in "Vaduz"?
** They probably landed in St. Gallen-Altenrhein Airport, which is in Switzerland and 50km away from Vaduz. Liechtenstein is in the Schengen zone, so they can go between it and Switzerland without needing to go through border officials.
!!FridgeHorror

* Directly after the events of the episode "Fitton", Douglas's wife Helena confesses to her affair with her Tai Chi instructor, and Douglas and Helena's marriage proceeds to break up. This information is not revealed to the other characters (or the audience) until the later episode "Limerick". So, for the entirety of the episode "Kuala Lumpur", Douglas, who is a recovering alcoholic, frequents a series of fully-stocked illegal bars around the airfield while going through a difficult time in his personal life and surrounded by people who are under the impression that he is a happily married social drinker.
** In "Gdansk", Douglas seems uncharacteristically aggressive towards Martin's jabs about pretending to be a captain for Helena, and proposes several deals which would forfeit Martin's right to tease him over it. On first listen, this is seemingly because of his own guilt over lying to her, or dang, even just over his own pride being wounded. Not until the reveal in "Limerick" do we realise that, chronologically speaking, "Gdansk" likely takes place not long after he came clean and Helena revealed her affair and their marriage collapsed...
* As of the penultimate episode, Carolyn, Arthur and Martin all have happy endings waiting for them in Switzerland, and giving up MJN Air is in all of their best interests. Douglas, on the other hand, given his age and his previous track record, will be left without a job and almost unemployable. His interactions with Herc show him becoming unhinged at the prospect of having to answer to someone other than Martin, so even if he landed another job, it's highly unlikely that he'd keep it for long (Heck, even assuming that he did manage to keep one, he'd have to be on best behaviour the whole time and would probably wind up bored and miserable. Goodbye, zany schemes and flight deck games). The way he talks about his social life hints that he is very rarely honest with other people about his troubles- Martin was probably the closest thing he had to a true friend. So, [[TearJerker he'll be a former alcoholic losing his job while going through a divorce,]] with ''no support network whatsoever...''
** Very, very, very happily Jossed. Douglas is [[spoiler: captain of MJN - now OJS - with Herc as his first officer.]]
* Douglas seems to still have a fixation with alcohol, even though he cannot drink it. He steals Mr Birling's whiskey, tries to con Carolyn into giving him expensive wine, he goes out of his way to help maintain an illegal social drinking culture at the airfield, and pretends to drink even when the social context doesn't require it (see: his "vodka" in Fitton, his first cabin address in Abu Dhabi). We all know how fond of games and challenges Douglas is- perhaps he's just playing "How long can I stay on the wagon?" with himself- and as usual, he seems to be winning. But what happens when he gets tired of playing?
* Arthur's attitude towards Gordon raises some very unsettling suspicions. Gordon is, apart from aunt Ruth, the only person Arthur shows true disdain towards and it terrifies him when Gordon is just near him, let alone anything else. He violently opposes Gordon having Gertie because of the way he would treat her. [[NightmareFuel How horribly did he treat Arthur and Carolyn for him to be so terrified?]]
* The 'happy ending' of Zurich results in MJN Air getting a big windfall of money. Great, right? Except Carolyn's had money before and not made MJN a going concern. How long until they've spent all that and are right back in the 'next disaster will end the company!' scenario once again.
** But in the divorce she got Arthur, the house and GERTI, but no money. Now she still has all those things, plus about £17m in gold, so they'll be perfectly alright.
*** In fact, Carolyn says in "Douz" that she did get a lot of money in the divorce but lost it running MJN. Getting the [[spoiler:gold wiring]] out of GERTI means she'll fly a lot better and more fuel-efficiently, and also leaves plenty of money to fix any other problems she's picked up over the years, invest in better marketing and whatever else they can do to reduce costs and generate revenue. "Yverdon-les-Bains" confirms that Mr Alyakhin has indeed become a regular client, which will also help.

!!FridgeBrilliance
* In Zurich, Carolyn's ringtone is "Questa o quella" from Rigoletto - the opera she and Herc went to on their second date. The lyrics are appropriate, being the words of [[TheCasanova a ladykiller unfazed by a challenging conquest.]] And this date marked the moment where Herc turned from TheCasanova into LadykillerInLove.
* In Gdansk, Carolyn confidently says the Disney character Goofy is a cartoon cow. Arthur corrects her that he's a dog. In Zurich, we find out Arthur's drawings of Goofy are completely unidentifiable - maybe his mum was remembering one of those?
** Or Arthur watched ''WesternAnimation/MickeyDonaldGoofyTheThreeMusketeers'', in which Goofy falls in love with [[spoiler:Clarabelle Cow, who ''is'' a cartoon cow.]]
* In "Limerick", Arthur, who is terrible at the NATO phonetic alphabet, immediately knows that G is Golf when asked. This makes much more sense when you realise that G is part of GERTI's name, and Arthur would have heard Martin and Douglas using her NATO phonetic alphabet name Golf Echo Romeo Tango India (as they do in the series) several times. Martin and Douglas just never asked him E, R, T, or I.
** And earlier in the same episode, when Martin hints that F is "a type of dance," Arthur immediately says "TANGO!"