But she also couldn’t help wondering why Donald had met with Bart in the Lake District in the first place. She knew it wasn’t for afternoon tea. There had to be more to it than that.

Maybe it would be better for all of them if Lord Reilly never woke up.

Chapter 25

Lance drew a diagram for Kelly.

‘You can imagine what happens to any chunk of metal when five blades above it are turning at 290 revolutions per minute.’

‘It spins,’ she said.

‘Exactly. That’s where the power comes from. It has to have a counter force, and that’s what the tail rotor provides.’

‘But it’s tiny,’ Kelly said.

‘Think tug boat. It’s just physics, it works,’ Lance said.

Zoe was being very patient.

‘What might cause the tail rotor to fail?’ Kelly asked.

‘Hydraulics leak, something mechanical like nuts and bolts being poorly maintained, wear and tear. But all of these things should set off the appropriate alarms and give the pilots a viable picture to work with so they can stabilise the situation.’

‘Unless it’s catastrophic,’ Kelly said.

‘Exactly. And that’s what our focus is on,’ Zoe interjected. ‘I’ve got people examining as much as they can related to the tail up there.’

‘I don’t know how you can work your way around a mess of wires and metal,’ Kelly said.

‘They know exactly what they’re looking at,’ Zoe said.

Kelly believed her. ‘I’m sure they do. How do you rule out sabotage?’ she asked.

‘By ruling something else in. It’s a painstaking process of elimination and might take time, but it’s all we’ve got, unless we get lucky.’

‘Whitehall is breathing down my neck, I haven’t got the luxury of time,’ Kelly said.

‘Tough, they’ll have to wait. You can’t rush an accident investigation,’ Zoe said.

‘I agree,’ Lance said. ‘But you could start with the things that would rule out sabotage,’ he said.

‘And that’s what I instructed before we left the mountain, Kelly.’ Zoe turned to her. ‘There are certain places to look for patent tampering, but if it wasn’t an accident, then I doubt it’ll be made obvious.’

‘How skilled would somebody have to be to pull it off?’ Kelly asked. ‘And could the pilots have been in on it?’

‘Not unless they were suicidal,’ Zoe said. ‘It’s something we’ll look at – their mental health. Lance, you knew them?’

‘I taught them. But what I’ve learned is that you can never predict somebody’s mindset,’ he said. ‘They can appear the happiest of people on the outside.’