Page 16 of V2

Mike said sarcastically – looking at the photograph rather than her, as if he couldn’t bear to address her directly – ‘Yes, but they have to get the missiles into the trees in the first place, I assume?’

‘They do, sir, but they must be bringing them in by rail at night. By the time it’s light enough to fly a reconnaissance sortie, they’ve already transferred them into the woods.’

Now at last he looked at her. He gave a slight slow shake of his head, which seemed to her to convey several layers of meaning all at once – reluctant admiration for the ingenuity of the enemy, irritation at the uselessness of Medmenham, and underlying that a certain rueful amusement, meant for her alone, that they should find themselves having such an exchange. He turned to the man from Bomber Command. ‘Can’t we just flatten the woods?’

‘Obviously we’ve looked at that, sir. Two big drawbacks. One, we’d probably have to go in daylight, and there are heavy flak defences in that area: our losses would be unacceptable. Two, it’s very close to The Hague. If we bomb from eighteen thousand feet, which is as low as we dare go, there’s a grave risk of heavy civilian casualties, and no guarantee at the end of it that we would have knocked out all the launchers.’

The air commodore sank back in his chair and put his hand to his bandaged forehead. He looked paler than at the start of the meeting. Even from her place at the end of the table, Kay could see that he was sweating. A silence ensued. And then a small man sitting opposite her raised his hand. He was in his fifties, a wing commander according to his insignia, but most unmilitary-looking, with thick spectacles, a toothbrush moustache and a snowfall of dandruff on his collar. He might have been a bank manager in civilian life. ‘May I make a suggestion, sir?’

Templeton squinted at him. ‘Yes, please do. I’m sorry – I don’t think I know you.’

‘Knowsley, sir. Clarence Knowsley. Home Defence, Fighter Command. The Filter Room? We have met.’

‘All right. Go on.’

‘If I may?’ He went over to the map. ‘Last Sunday, the Filter Room created a forward radar base on the Continent. We deployed three mobile GL Mark Two units and two of the new experimental Mark Three high-looking radars to Belgium – here, to be exact, around the town of Mechelen. That’s within about seventy miles of the launch sites, which is as close to the front line as we can get. The area’s only just been cleared of Germans. Because of its position, and the lack of hills, it gives us a perfect side-on view of the missile’s trajectory. These new radars have cathode-ray direction-finding displays, so not only can we pick up the rockets once they reach an altitude of about thirty thousand feet, we can also record their flight path before they pass out of range.’

‘And that helps us, does it?’

‘It could do, sir. When this all started, we rather hoped the V2 would turn out to be guided by radio signals, which we might at least have been able to jam. The Germans obviously anticipated that. They don’t use radio guidance. We believe the missile to be purely ballistic – that is to say, the engine shuts off and it follows a perfect arc, similar to if one throws a cricket ball from the outfield. And that is a potential weakness we might be able to exploit.’

He broke off, obviously unused to speaking at such length. The air commodore made an encouraging gesture. ‘Go on.’

‘Well, a ballistic arc is mathematically calculable. If we have data giving us the missile’s trajectory at the moment it becomes ballistic, and if we have the precise point of impact, then it should be possible, in theory, to work backwards and calculate the spot on the boundary from which the cricket ball, so to speak, was thrown.’

The officers looked at each other. Templeton sat forward in his chair. ‘That’s quite an interesting notion. The question is: can we exploit it operationally?’

‘Obviously we’ve been thinking hard about that. Essentially, it becomes a race against time to put the two halves of the data together. The first half, from the MRUs in Belgium, can start to be collated on site a minute or two after launch. The second half can be supplied from Stanmore as soon as Home Defence radar gives us the point of impact – that’s about three minutes later. So for the sake of speed, the calculating needs to be done as close to the mobile radars as possible.’ He turned to the officer from Fighter Command operations. ‘How long does it take to get a Spitfire off the runway at Coltishall and over the Dutch coast? Twenty-five minutes?’

‘About that. Give or take.’

‘So if the planes are scrambled as soon as a missile launches, and the point of impact is reported to Belgium as soon as the V2 hits, we’d have about twenty minutes to make the calculation, locate the rough area of the launch site and get the coordinates radioed to the pilots while they’re over the North Sea. In theory, we could bomb the target, say, thirty-five to forty minutes after launching, while there are still men and vehicles on site.’

Templeton turned to his aide. ‘Did you get all that?’

The flight lieutenant was still writing. ‘Yes, sir.’

‘What does everyone think? Is it feasible?’

With varying degrees of enthusiasm, the officers agreed it was.

Templeton said, ‘It gives us a chance, at least. And in the absence of any other options, it’s certainly worth a try. Good. Let’s start tomorrow.’

Knowsley looked alarmed. ‘I’m not sure we can start as soon as that, sir.’

‘Why not? You said yourself we have the radar units in place. And we have 303 Squadron at Coltishall. The pilots are familiar with that area of Holland.’

‘We still need the personnel in Belgium to make the calculations.’

‘Are the calculations difficult?’

‘It’s fairly sophisticated algebra. It requires an ability to use a slide rule, for a start. I’ve pulled a few girls out of the Filter Room and started training them – with somewhat mixed results, I have to admit.’

‘How many do you need?’

‘For round-the-clock coverage, to begin with, at least eight.’

‘Come on, Wing Commander! There are a hundred and eighty thousand WAAFs in the country! It has to be possible to rustle up eight capable of using a slide rule by tomorrow, surely?’