The decision to add a second hospital-based EMS helicopter

Abstract An analysis of the first seven years of performance of our hospital-based emergency medical services (EMS) helicopter was conducted to evaluate the possible need for a second aircraft. A survey of seven hospitals currently operating two or more helicopters resulted in a consensus that one helicopter can effectively perform only 70 to 90 flights per month. The number of requests for our helicopter service has increased 148% from 610 to 1,512 in seven years while the number of completed missions has increased only 92% from 486 (40.5/month) to 935 (78/month). Requests denied due to inclement weather (265 in 1988) cannot be captured with a second visual-flight-rated (VFR) EMS helicopter; however, those missed due to maintenance requirements of the helicopter and overlapping requests (232 in 1988) can be captured. The need for a second aircraft exists when the number of requests for the service grows while the number of captured flights plateaus. Our data and industry survey suggests this will occur at 75 captured flights per month. Affordability and continued overall growth of trauma and other critical care referrals to the base hospital (s) is mandatory. This study provides a model for hospital-based EMS helicopter operators to apply to the decision whether to add a second aircraft.