‘But we chose you guys for the programme because we think you have the qualities to help those who need it, even in the most extreme circumstances. In the field, it’s just you and the team and your training and your instincts. Transcending fear to make a difference is an incredible privilege.’

It rings so true. These are my people. This is where I am meant to be.

After a month of drinking in every bit of knowledge and every skillset, I’m sent back to my air ambulance base. To begin with, I’m literally excess baggage on the helicopter, travelling alongside the crews but unable to do anything but the most basic tasks.

I make friends with the pilots first; I can talk aerodynamics with them and purr over the controls.

Next, I win the paramedics over with my willingness to clean up the mess that fills the helicopter after we’ve handed over a patient. Plus, they realize quickly that I can cannulate or intubate in my sleep.

Gwen, the consultant, is the hardest nut to crack, but still she’s nowhere near as frightening as the average ward manager. Plus, she’s awesome. If I ever get to be half as good a doctor as she is, I will be happy.

Life at base is about being prepared, like grown-up Girl Guides or St John cadets: stocking, restocking, counting, waiting. But when the red phone rings, the change is instantaneous. The first few times it happens, my response is physical – dry mouth, goosebumps, mild tachycardia. My body readies itself for the unknown and we board the helicopter.

‘RTC, Dorking Bypass. One artic, three cars.’

On the way, I always try to build a mental model of what we’re going to face. As we approach the crash, the pilot navigates the hazards of power cables and rows of houses to land in a playing field.

Gwen deplanes with Lars, her favourite paramedic, and I jump out behind them. My instinct to run first and think later is probably my biggest weakness, but I’m trying to learn from Gwen as she holds back, assesses the scene, establishes who is in charge.

‘Hi, what have we got?’ she asks the fire officer.

‘Car versus lorry. Couple of other cars shunted behind. The occupants of the Honda have come off worse. Two females, passenger looks worse and she’s pregnant.’

I’ve spent four years dealing with the consequences of these David and Goliath accidents in the hospital setting. But as we approach, it seems miraculous that anyone might have survived inside the warped remains of the little blue hatchback.

The passenger’s belly and the airbag have the same cushiony roundness, but everything else is harsh and sharp, the angles of the car helter-skelter.

Gwen leans in. ‘All right, love, my name’s Gwen, I’m a doctor and we’ll have you out of here very soon and off to hospital. Where does it hurt?’