By: Angel MedFlight Contributor
Much like a John Woo film, we at Angel MedFlight see our air ambulance medical crew and pilots walking toward our jets in slow motion on a large, open tarmac, the wind gripping their uniforms, white doves flying past... alright, maybe that last part was a little too dramatic, but you get the idea. Our crew are heroes in our eyes and in the eyes of our patients. They are ready to take off at a moment's notice to help people in need.
The medical gear is stocked, the Learjet is fueled, and the crew is suited-up. As the supplies are strategically placed and patient preparations are being made, the pilots are performing their final check list before takeoff. Aviation West Charters and Angel MedFlight Chief Pilot, Kindle Tannery, explains a few of the typical pre-flight checks. Let's take a look at that process.
Prior to takeoff, Tannery explains that the pilots put in the determined speeds using the Flight Management System. As the set speed thresholds are met, the pilots call out to each other every occurrence as they happen on the display.
"There are three main checks to perform during a takeoff: Airspeed Alive, cross check, and V1," Tannery explains. These verifications are standard on all Angel MedFlight air ambulance performance check procedures. These checks will take place while on the move.
"Airspeed Alive cross checks the Captains flight instruments with the Co-pilots instruments. Aircraft takeoff airspeeds are determined based on the altitude, temperature and weight of the aircraft," Tannery continues. "These variables play a vital role in determining the speed that will be necessary to meet the required threshold - or 'no turning back now' point. This process also verifies that all instruments are working properly. We are generally at about 40 knots when the 'airspeed alive' call is made."
"A 'cross check' is then performed between the pilot and the co-pilot to verify gauges are reading the same. Essentially, both pilot and co-pilot airspeed indicators need to be at 90 knots at this point in the takeoff. This process ensures accuracy between panels. If there were any inconsistencies, we would abort he takeoff."
"V1 is essentially the 'decision speed' or the accelerate / stop distance. This is the last opportunity to make the decision to continue or abort, if necessary. When you cross that speed threshold, there is no stopping the takeoff process. The threshold speed is determined by the plane's weight and the outside temperature. If the weight and temperature are higher, the speed threshold is more. Lower weight and lower temperature means a lower speed threshold."
"The Learjet 60 is very fast. It's the Corvette of all aircraft," says Tannery. "The engines create 9200lbs of thrust combined at takeoff, so performance checks need to be made quickly and accurately. Good training is required and safety is always our number one goal as Angel MedFlight air ambulance pilots."