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Old 8th May 2009, 11:59
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h3dxb
 
Join Date: Mar 2009
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In 1000 ft ? Fasten yr seatbelts and avoid the impact.

Normal Airbus logic is (with enough altitude and yes it' called windMILLING)

Air autostart sequence
When the autostart sequence logic is active in flight, the ECU initiates the automatic starting sequence to control:
 the opening of the starter SOV (for starter assisted operation when N2 lt; 16 percent, opening and closing with starter reengagement protection).
 the excitation of both ignition systems when starting is controlled.
 the opening of the HP fuel SOV and FMV when N2 > 12 percent below
20000 ft or N2 > 15 percent above 20 000 ft.
 the closing of the starter SOV and cutting off of the ignition at N2 > 50 percent.
In the event of an abnormal start, the ECU provides fault annunciation to the
FWC, which generates warning messages for pilots action.
The ECU has no authority to abort the starting sequence in flight. The ECU
identifies the windmilling or starter assisted air start conditions according to the flight environmental parameters (Mach, altitude), and the engine parameters.
The engine can be relight without using the starter, provided N2 > 12 percent
below 20000 ft or N2 > 15 percent above 20 000 ft.
In order to guard against the effects of some failures which could jeopardize
the in–flight restart the ignition and fuel are selected ”ON” by the ECU in the
following conditions:
 insufficient air pressure at the starter SOV inlet (if bleed manifold pressure
parameter is valid).
 the starter SOV does not open or acceleration problems

Looks that we need in dual Eng failure the APU, but I think at normal Airspeed we have round about 20% N2 with windmilling.
Autostart sequence is activated by Mode selector in IGN/Start

rgds
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