They would normally have used the police helicopter back then too, but it was grounded due to a recent crash. London now has an air ambulance service, which it

They would normally have used the police helicopter back then too, but it was grounded due to a recent crash. London now has an air ambulance service, which it didn't at the time- though the air ambulance also have some impressively fast cars (Skoda Octavia vRS IIRC) for when conditions don't allow the helicopter to fly.