tipiche chiavette airbus (sono quelle sopra le 4 manette, e quella al centro sotto alle 4 manette, dove si legge ENG START)
Engine Start up (A340)
The normal engine start procedure is the AUTO START procedure. In this case the FADEC prevents start malfunctions like hot start, stall etc. It recognizes all of these and takes appropriate actions for instance reducing fuel flow, cranking the engine, attempting new starts or cutting fuel flow. The air from the APU (APU bleed) allows to start 2 engines simultaneously.
The engine start up sequence is simple: 1 and 2 are started firstly to pressurize the green and blue system which supply the parking brakes and hydraulic actuators. An actuator is a little box that converts the electrical inputs to real rudder movements. The Boeing B707 for instance doesn't have this system. Engine 1 and 2 first, followed by 3 and 4. Check thrust levers idle.
Engine Start
Then set IGN/START to START - now an eye must be kept on the ECAM to check if APU bleed is stable. ENG1 Master switch is set to ON followed by ENG 2 when N2 of Engine 1 has reached 10%. Now monitor and check in the right order: Start valve open (now high pressure bleed air (minimum 30psi) air is blown into the engine), N2 IGN A or B, Fuel flow, EGT OIL PRESS ignition rising. FADEC (Full Authority Digital Engine Control) closes the start valve when N2 reaches 50%, now monitor EGT and ENG Vibration and the engine AVAIL which illuminates when the start sequence is over. Now the same is repeated for ENG 3 and 4.
When all engines are running stable set the IGN / START switch back to NORM which automatically switches the Packs back ON. If, for any reasons, there is an abnormal start DO NOT interrupt the FADEC protective and just follow the ECAM instructions if they appear.
Another procedure to start the engines is the MANUAL START, which is only used in exceptional cases, like high altitude airports or subsequent low APU bleed pressure or to CRANK the engine dry prior opening the fuel flow.
di fare una domanda seria in una fascia oraria dove sei on line é fritto .... 
