Page 9 - Volume 18 Number 10

the XL, its fuel shutoff and crossfeed handles are mounted at the base of the pedestal. An overhead panel covers electrical items, including lighting and anti-ice functions.Starting Up, Going UpBattery starts can be initiated with either engine, due to the nose- mounted battery location. The usual PT6A procedure is followed; fuel pump and ignition on, press start to stabilize Ng well above 12%, introduce low-idle fuel and watch for acceleration. With starter off at a stable 56%, prop moved out of feather and high-idle selected, the starter becomes a generator and, while the battery is recovering, the opportunity is taken to confirm the hydraulic pump’s operation by pushing the gear handle down, checking that it returns to neutral. At shutdown, the process will be reversed. To avoid stress to the starter/generator shaft, Piper’s checklist calls for turning the generator off during the second engine start until Ng has reached 10%, then using the generator to boost the start.Taxiing control is straightforward; no braking is required if the power levers are eased over the Beta gate. The nosegear casters up to 40 degrees for precise maneuvering. Pretakeoff checks are the usual governor and pitch lock tests, plus setting oil cooler doors, ice protection, controls, trim and environmentals. Prop sync and yaw damper are off during takeoff and landing.Takeoff torque is applied with a bit of margin left for building on the roll; the XL’s props turn at 1,900 rpm, while the Cheyenne I’s wind up to 2,200 for takeoff, 2,000 for max- continuous. The Cheyenne XL uses its 620-shp for takeoff and cruise but has a 500-shp restriction for climb, the price of not carrying the SAS system. The healthy flat-rating of the -135 engine, of course, means full climb power is nearly always available, while the Cheyenne I’s -11 engines may temp out.OCTOBER 2014TWIN & TURBINE • 7