It’s just as well AL Kennedy has a Scottish accent, since the burr makes her droll and almost compulsively ironic conversational manner slightly easier to take.

Nonetheless, she is still a daunting prospect. There’s the formidable ability; last week her novel Day, set in the second world war, scooped the £25,000 Costa book of the year. The Costa is just the latest gong on a glittering list including two appearances on Granta’s best of young British novelists, a Somerset Maugham award, the Saltaire Scottish book of the year, and the £75,000 Lannan literary award for fiction.

Then there is the public persona; like JK, she never goes by her full first names (Alison Louise), but remains behind two stiff initials. Not to pretend she was a man, or to indicate she is a feminist, or a lesbian (more of that later), but from a childhood admiration for writers such as JRR Tolkien and E Nesbit, whose personae, she felt, never got in the way of their stories.

Then there are the idiosyncrasies. The refusal to wear make-up (hates it), read newspapers (ditto), drink alcohol (allergic), or fly willingly on a plane (phobic). Flowing in and around all of this is her cutting-edge wit which, as we speak, might or might not be taking mental notes for her next stand-up gig in Glasgow.

Day by A. L. Kennedy

Kennedy shows characteristic boldness in this story of a former RAF prisoner-of-war returning to Germany to play the part of a British POW in a film

BACKGROUND

• Tale of war and redemption

• Bookies pick Kennedy as Costa favourite

• O'Flynn wins Costa

• Do your homework

Plus, I’ve woken her up. The 42-year-old associate professor in creative writing at Warwick University is staying at the “palatial” Wolseley hotel in New York, having just flown in from the celebrations in London.

But I thought you didn’t do flying. “I had to. I’ve been working out here and had to fly back to London for the night.”

She was the hot favourite for the Costa. “I wasn’t aware I was the favourite. I don’t read papers – 90% of a newspaper is rubbish.

“Papers are full of people I have never heard of doing something to their breasts.”

How did she get out to New York in the first place? “I came by boat.” That’s pretty grand; what sort of boat? “Well, this time of year there aren’t any freighters,” says AL in a matter-of-fact manner implying a working knowledge of international shipping systems. “So I sailed here on the Queen Victoria.”

A deserved result of all those prizes, no doubt. “No, I got a rather good price by booking myself in an indoor cabin with no window, close to the services. Only they upgraded me.”

What’s wrong with flying? “I just hate it. You feel as if they are trying to kill you. If something goes wrong there is no fall-back position. At least in a ship you will have two minutes of life in freezing water.”

Now, is that a joke, AL? “The book [Day] made it worse.”

Indeed, for a flying-phobic, research-oriented writer, choosing to write about the experiences of a young tail gunner in a Lancaster bomber sounds rather foolish. But at least she didn’t have to go up in one. She spent three years researching Day, immersing herself in the detail of air attacks, carpet bombing and gunnery training manuals.

“It’s an enduring obsession of mine. The policy that if you kill enough civilians from the air, you will not have to risk your own people. It rarely works. Unless you carpet-bomb people who live in tents. And you end up killing an awful lot of people, most of whom are noncombatants. Britain was outraged by aerial bombing until Bomber Harris and Dresden. And, of course, if we had bombed the oil refineries rather than the cities, then the German army would have been unable to move. And then the war would have not been waged.

“I spent years watching the bombings in Afghanistan reducing bricks into rubble, and rubble into dust, and still the war was not won. And then there were the preemptive strikes on Iraq.”

Unsurprisingly she managed to slot quite a lot in alongside Bomber Harris and his ilk. “Well, I couldn’t spend three years just researching. I finished another novel. I wrote screenplays. You can’t spend all your time thinking about a book that doesn’t exist. I spent about 20 minutes a day thinking about it. But if you do that for three years, you end up with a book. And I also did lots of stand-up.”

It’s unlikely, one must admit. An academic writer of literary fiction doing open-mic stints of comedy before a baying pub crowd.

“It’s a good training programme,” says AL, drolly. “And you know if it is working, because they laugh.”

Perhaps after a day making things up, it’s a relief to get behind the microphone and deal with the real world. “The interesting thing about comedy is that you have to find your voice. It’s a cartoon version of you, but it needs to be you.”

But who is AL Kennedy? She seems to excel at every area in the canon; novels, screenplays, poems, columns, jokes. She’s a lecturer, a stand-up, and an ordained minister (the position was bought on the web, apparently). She’s been a Booker judge.

Professionally, she could hardly be more out there. Privately, she’s as mysterious as, well, E Nesbit. She lives alone in Glasgow and once admitted to having sex only every five years. Her books don’t offer any answers. Thinly disguised autobiography is not the AL way.

“My job is about me being the f*** out of the way,” she comments. “It’s about writing the story and the less aware I am of me the better.” That’s not very customary, I tell her. Many novelists are only too happy to insert themselves into their novels. “Well, a lot of that stuff is a) boring and b) really not useful.”

There are rather a lot of things that AL considers not useful. Putting on make-up is one. “It’s a pain in the arse.” She admits her image has changed quite a lot; old photos reveal AL as a bit of a long-haired babe, now she is all short hair and sharp suits.

“Well, for years, a lot of the press thought I was a troglodyte living in a cave,” she says, affably. “Basically I have gone from having absolutely no money to being able to afford clothes that fit. And from having such a bad back that nobody was able to touch my head to a back which is moderately better, so I can have my hair cut properly.”

And if being thought of as a hermit irritates her, being thought of as a gay hermit irritates her even more.

“It’s not useful, because all the wrong people come up and try to score. You get put into the Big Gay Reading Event at book festivals. Gay people can tell I’m not gay from about 400 yards. Plus, it’s a festival! I could be hanging out with firefighters! Remember, I have a limited lifespan.”

She certainly has no time for idiots. Until recently, AL would review her reviewers, categorising their efforts as good, which would include comments saying that she was “a Booker contender”, bad, where they’d accuse her writing of being a “sprawling and harshly seedy saga” and silly, where the reviewer would say something like “ignore most of the plot”.

“It should be possible to review the reviewer’s language,” she says. “I care about people who use words. If you want to be in a climate where people use words with accuracy, you have to say what you mean.”

When she won the Costa she used her two minutes in the limelight to condemn the education system in general, and public libraries in particular, for a decline in the use of the English language. “It’s not those libraries which have a couple of computers, but ones where there is a bank of computers with no bloody books. You can’t use a computer if you don’t have a grip of language! And if you have a grip on language you can defend yourself against bad law. Or going off to war. Or a dodgy dossier.”

Ah, the infamous dossier. Does she think it was sexed up? “If you read that dossier it was not a case for war. It was a bunch of excuses aimed at defending the decision-makers against future prosecution. It was crafted in an alarmist way. And people ran with it.”

AL’s patently abundant capability with language cranks into top gear when she considers the press. This is not because she is a self-Googling narcissist (apart from those reviews). She certainly has no intention of going on a reality show. (“The clue is in the title. And I have read Nineteen Eighty-Four, you know.”) No, it’s the general landscape that worries her. In her view, everything has been diluted and demeaned. “It’s not a conspiracy. It’s just stupidity. And in the worst instances, it kills people.”

Her meticulous research into the years of the second world war only consolidated her view. “The press then was quite a different animal. Because everyone was necessary during the war, and because ordinary people had been so courageous, there was a different media. A media which was beautifully written. Which was clear. And which liked people. There was none of the underlying loathing.

“If you pick up a paper, so much of it is about how fat we are, or how stupid we are. Or how our politicians are scum. Papers are full of gossip, spun facts, and filler. With photos of people who forgot to put their knickers on. Listen, I used to work in special care homes. There were loads of people in them who forgot to put their knickers on every day. It just meant they weren’t very well.”

When I stop laughing, I ask her what she is going to do with the Costa money. Intriguingly, she tells me she is going to give some of it to the investigative journalist Greg Palast. “I’m going to send him something so he can carry on with his work. You can’t care about something and not do something about it.”

Let other award winners spend their tax-free gains on trivia such as swimming pools. But how much will AL give him? “Oh, only about £1,000. I’m not that generous!”

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