I am curious about this as I am working on a project the documentation of which involves the name of that airline, and not only for me but also it seems for other people it seems necessary to type out the text then go back and delete the ‘u’.
Not in my experience, purely because it’s such a well known brand. But for someone unfamiliar with the brand, then it would be automatic to add a ‘u’.
Being an acronym that is no longer capitalised as if it was an acronym, it’s easy to see why there’s a problem. Even as an Australian, I find I need to mentally correct myself.
My WAG is “yes”, many (perhaps a large minority of) non-Australians will tend to insert a “u”.
Because ‘q’ is so often followed by ‘u’ I find my fingers automatically following the pattern on the keyboard. Typing a ‘q’ then an ‘a’ feels odd, and in the middle of typing I think I’d always end up having to delete the ‘u’.
I see native English users misspell it the whole time.
Keep in mind that just as there is no “I” in “team”, there’s no “u” in "Qantas’.
Particularly when you’re a passenger, and it goes on strike.
I wouldn’t go back and take out the “u”, because until I saw this thread, I thought there really was one. I guess my brain just fills in a u-after-Q.
What does the “also” in the thread title refer to?
The OP is a German speaker, and presumably tends to put a ‘u’ in Qantas. (Interestingly, I just now had to delete it as well; my finger automatically put it there. I’m a French speaker.)
What I find strange is that the airline’s name seems to be pronounced “kwantas”. Since there is no ‘u’ there, I’d think it should be pronounced “kantas”.
I have to admit I would have spelled it incorrectly. And I guarantee you in about 9 months when I forget this thread, I will continue to spell it incorrectly.
I can’t really think of any English word that starts with a Q and doesn’t have a U following it - well, other than Q-Tip.
You spelled it wrong. It’s Quantas. All words with a Q in them have the Q followed by a U, like Iraqu.
Just this minute, after reading this thread, I went and typed Qantas into Wikipedia to see what it is an acronym for. I typed a U after the Q automatically, and had to backspace, even though I had this in my mind. I think a whole lot of English speakers wll do this. It is a reflex to type U after Q. I’m not sure if it would be as common for people writing by hand.
And the well-known scrabble word, Qui.
A “Q” not followed by a “U” is rather unnatural, don’t you think?
Google knows better. With incremental search enabled, if I type in quant it shows me quantum and other things, but as soon as I type in quanta it shows me a bunch of Qantas stuff.
I don’t know of any English words having q without a u, even at the end. Only foreign words and names.
That’s because you don’t play Scrabble. Behold, all legal in Scrabble :-
QI
QAT
QIS
QADI
QAID
QATS
QOPH
FAQIR
QADIS
QAIDS
QANAT
QOPHS
TRANQ
UMIAQ
FAQIRS
QABALA
QANATS
QINDAR
QINTAR
QIVIUT
QWERTY
SHEQEL
TRANQS
UMIAQS
QABALAH
QABALAS
QINDARS
QINTARS
QIVIUTS
QWERTYS
QABALAHS
MBAQANGA
QINDARKA
SHEQALIM
MBAQANGAS
I even know what some of them mean.
It stands for Queensland and Northern Territory Aerial Services. Once you know it’s an acronym (even without full capitalisation) it’s easy to remember that it doesn’t need a ‘U’.
Not to say that your fingers still won’t type one. Just that you know to backspace after. 
Some are Chinese, some are Hebrew, some are Arabic. The ones that aren’t are either shortened words (tranq) or just a collection of letters (qwerty).
I noted the other day that newspapers in Sweden spell it correctly, but whenever the company was mentioned in the radio it was pronounced “kwantas”.