How wide body aircrafts are started(airbus 380/340 etc:?

Question

If by Airstarter oe elctric start , please let me know how it works

Answer 1

They have an APU, or Auxiliary Power Unit in the rear of the aircraft.  An aircraft APU is a relatively small gas turbine used to produce shaft power to start the jet engines, usually with compressed air, and to provide electricity, hydraulic pressure and air conditioning while the aircraft is on the ground. In many aircraft, the APU can also provide electrical power in the air through a generator installed on the gearbox.  Some older aircraft or planes without an APU use a Ground Power Unit which serves the same purpose.

Answer 2

Most aircraft have APU (auxilliary power unit), as explained already using its pneumatic power. If none or APU out they use an Air Start Unit (ASU).

Usually during starting with the A340 if you use igniter A the last time on auto start it will now use ignition B.Bleed air passes through the same apu bleed (air) line and goes to the engine 1 and 2 being left doesn't need to open the crossbleed valve. This air goes through the now open start valve and goes to the starter valve motor to drive a gearbox where another shaft in turn drives the engine N2 compressor.

now the engine rotates until its self sustaining speed around 46% where the starter and ignition cuts out.

Answer 3

I'm not exactly sure but i have never heard of air starter on a jet engine.

Plus an electric motor is an alternator which generates electricity, so it can start a plane and then the engine will generate power for the whole aircraft. The engines also pressurize the cabin.

But one thing, wide body aircraft wouldn't use any particular different engine, its more about weight. Not including streamlining which would definitely be reduced to a minimum.