Well, I missed the anniversary of the first moon landing, didn’t I? And I’m the one with the astronomy background. So I looked around for a similar subject to turn into a puzzle. The initial Apollo missions followed on one after the other at quite a dizzying rate (one can hardly imagine it happening today, after four decades of efficiency talk…). So the Apollo 13 mission was quickly in the frame. (The launch date was also my sister’s first birthday, though I doubt NASA factored that into their thinking.)
I later discovered that the Tom Hanks film was released 25 years later, so that the puzzle also captures the silver anniversary of another commemoration. The film itself is remarkable for keeping the tension high even though you know the outcome.
Although the basic story of the Apollo 13 mission is familiar enough, the first step was to read up the details for any additional bits of information. It quickly became clear that the significant event was the movement of the astronauts from one component of the ship to the other, so that they could continue to use the powered section. Somewhere about then, I guess, the basis of the title lodged in the mind. There was a lot of counting of letters – fortunately, the letters in the names of the astronauts came to an even number (or, at least, not a prime number), so that it was possible to think of extracting their names in “clumps” and moving them around the grid.
Also around this point the shape of the grid became clear. I’d always had a vague idea it was going to be more rectangular than usual, to represent the juxtaposition of the two modules. My initial thought was for it to be horizontal, probably because that is the more common way such spacecraft were depicted. But, of course, there is no specific reason why it should be horizontal – there’s no obvious up/down/left/right arrangement up there. So the final layout was as much determined by accommodating the puzzle on the page of the i as anything.
It seemed reasonable that if I removed the astronauts by extracting pairs of letters from words then I should add those pairs of letters to words in the other section of the grid. But the grid shape I’d ended up with implied a large number of short answers. It took a bit of juggling to (almost) avoid adding a pair of letters to a two-letter word, but I think it just about worked.
Also I was concerned about the words that crossed the middle row, and was at pains to keep them “pure” – hence most of the amendments were in across entries. Two of the straddling words allowed me to work 13 into the grid, though I then left myself with the problem of clueing 73. Random numbers aren’t fun to clue (three AWOL trombones?). I have a curious little book called Rogerson’s Book of Numbers (found remaindered at the local university bookshop), and this revealed that 73 is the number of Seth’s accomplices in tricking Osiris, and the number of rules of the Benedictine order, neither of which struck me as useful for clueing purposes.
At a very late stage I noted the ambiguity about the removal in the first entry – OILCOURS could be from either OILC(OL)OURS or OILCO(LO)URS, but that was resolved by the added letters in the lower half, and the fact that OL didn’t attach to VELL particularly well. So I left it in place, and no-one raised it as an issue.