Air Ambulances: Fixed-Wing v. Rotor-Wing

When people say “air ambulance” they’re obviously talking about a form of medical transport that flies in the sky versus the boxy vehicle that races to emergencies on the streets around town.  But it’s not as clear whether they’re talking about airplanes or helicopters.

Air ambulance defined

Air ambulances are either fixed-wing aircraft or rotor-wing aircraft.  The technical definition: “A fixed-wing aircraft is an aircraft capable of flight using forward motion that generates lift as the wing moves through the air. Fixed-wing aircraft are distinct from rotary-wing aircraft in which wings rotate about a fixed mast and ornithopters in which lift is generated by flapping wings.”[1]  In plain English: a fixed-wing aircraft is an airplane and a rotor-wing aircraft is a helicopter.

Both fixed-wing air ambulances and rotor-wing air ambulances offer distinct advantages over ground ambulances in certain situations.  In emergency trauma situations, we know that there is a certain window of time we have to get a patient to a trauma center to maximize their chances of survival and recovery.

Choosing the best form of medical transport

Choosing the best form of medical transport, in these emergency situations, is about making sure the patient gets to the trauma center within that window of time.  So emergency medical professionals will typically choose an air ambulance over a ground ambulance when:[2]

• Just getting to the patient took a while, depleting the time left to get the patient to a trauma center within the ideal time frame for best clinical outcome.  For example, when the patient was injured in a remote area or trapped in a crashed car.
• Distance to the trauma center is greater than 20-25 miles.
• Traffic conditions make it unlikely that a ground ambulance can get the patient to the trauma center within that ideal window of time.
• Even when there is a trauma center within 20-25 miles, if the emergency involves multiple patients, taking all of the patients to the closest trauma center(s) could overwhelm them.
• In some cases Emergency Medical Services systems require a ground ambulance to transport the patient to the nearest hospital, even if it has no trauma center.  Often, an air ambulance can transport the patient directly to the trauma center.
• The patient needs medical care and stabilization at the ALS (Advanced Life Support) level, and there is no ALS-level ground ambulance service available within a reasonable time frame.

Medical air transport: fixed-wing or rotor-wing?

Rotor-wing and fixed-wing aircraft typically play very different roles.  Helicopters can be seen as substitutes for ground ambulances, because they can land almost anywhere.  But fuel capacity gives them a relatively short range.  They typically serve patients in true emergency situations, where quick access to a trauma center is literally a matter of life and death.

Because airplanes are less flexible about where they can land and take off they are typically not used to transport patients from the scene of the emergency to the hospital.  They also have a much longer range than helicopters do, so they can travel farther distances without refueling.  Yet they can still offer life-supporting care for patients who are critically ill or injured.  So fixed-wing air ambulances are more often used to transport patients from one hospital to another.

[caption id="attachment_292" align="aligncenter" width="548" caption="Diagram of a Fixed Wing Transport"][/caption]