Since the Surrey and Sussex Air Ambulance was set up last June, it has helped save hundreds of lives thanks to its combination of speed and skill.
The period following a serious accident is crucial – and once a call is received, the helicopter can be with a patient anywhere in Sussex within 15 minutes, travelling at 150 miles per hour.
Based in Dunsfold, just inside the Surrey and West Sussex border, the service has handled more than 400 calls so far.
Staffed with a fully-qualified doctor, plus a critical-care paramedic, who has a higher level of training and skill to support the doctor, plus an experienced pilot and plenty of medical supplies, the team can provide more extensive care to a patient direct at the scene, as pilot Peter Driver explains.
"It does make a difference in the terms of the level and standard of medical care which can be provided at the roadside, the motorway side, or even in a field.
"Patients receive a higher standard of treatment which would normally be found only in a hospital.
"We can also get to locations which we would never be able to access in a normal ambulance."
Once the emergency services control decides the air ambulance is needed, the crew has three minutes to be in the air.
While the pilot is starting the helicopter, the medical team get the location and details of the patient.
On route, the team keep in contact with the emergency services. While the doctor and paramedic are planning what equipment they might need on the ground, the pilot is planning where to land.
In the case of an accident on a motorway, the pilot has to circle the area until both carriageways are shut off for safety.
"We all work as a team when we're on board," explains Peter.
"The other guys have navigational skills so they can help me. And when we're at the scene, we're all helping each other.
"And it's not a question of arriving, then just taking over the scene.
"When we get there, our first question is 'how can we help?' We all work together, supporting each other to get the right result for the patient.
"And because they are being taken to the most appropriate hospital, they have a much better chance of survival."
Since the rescue service was launched, the helicopter has attended a wide range of incidents, including road traffic accidents, horseriders who have come off their animals – and last month it was called to Selsey where a man had fallen off the roof of his house.
One of the important aspects of the air ambulance's work is that because there is a doctor on board, extra time can be spent treating the patient.
Afterwards they can be taken to the most appropriate hospital, whether it's the A&E department, a specialist burns unit or a dedicated trauma department.
For the team, the job is very important and a service of which many people are still unaware.
"It's a very worthwhile job, and you feel it is making a difference," said Peter.
"We have definitely helped people who might otherwise have died and the air ambulance does have a tremendous ability to affect the outcome of all patients.
"The air ambulance is sadly something you never really think about until you really need it."
The Sussex Air Ambulance appeal to raise 250,000 was launched in June, 2005 by actress Penelope Keith.
Sussex was one of the last counties to get its own air ambulance service.
All air ambulance services around the country are registered charities and depend on fundraising by the public to continue. They receive no government or lottery funding.
From Dunsfold, the Surrey and Sussex Air Ambulance can get to Chichester in just under nine minutes and to Bognor Regis in just over 11 minutes.
The Surrey and Sussex branch works very closely with the Kent Air Ambulance service.
All medics agree that after an accident, a patient has a critical 60 minutes to receive medical treatment to ensure recovery before vital parts of the body start to shut themselves down.
For more information about the charity telephone 01622 833833 or see the website.
The Surrey and Sussex Air Ambulance will be holding an open day at Dunsfold Park, on Sunday, June 1 from 11am until 4pm.
Visitors will be able to meet the crew, look round the helicopter and find out about other emergency services such as fire and rescue, ambulance and the police.
For a video check back with the Observer website.