An air ambulance company that provides urgent medical transportation between islands and to the mainland is expanding its fleet, the company announced yesterday.

AirMed Hawaii is adding its first long-range jet and a fourth interisland medical jet, growing its fleet to five aircraft.

The company did not disclose the long-range aircraft type, but said the smaller interisland plane was a King Air.

In 2008 the company stationed a King Air C-90 plane in Hilo to fly patients from Big Island hospitals.

The propellor-driven turbo prop, powered by turbine engines, will allow AirMed staff to transport patients from Hawaii hospitals to the mainland.

AirMed is the exclusive urgent medical transport for Kapiolani Medical Center for Women & Children.

Currently, the company flies a long-range jet from sites on the mainland or Hong Kong when urgent transport to the mainland is needed.

The company typically flies about 20 transfers to the mainland annually, a company spokeswoman said.

Both planes are being outfitted at AirMed Hawaii's parent company facility in Birmingham, Ala. They will be delivered within 45 days, the company said.

Based in Honolulu since 2006, AirMed Hawaii is the state's only accredited air ambulance service, providing medical transportation between the islands at all hours, it said in a news release.