I asked this question on another thread (R&N), but no response. Capt S&L or someone please!
It appears that the 'LOW' indication is set at 907kg by Boeing (for ETOPS). It is changeable to 453kg by operators for non-ETOPS I understand.
The QRH calls for a drill at the 'LOW' indication, presumably to ensure adequate fuel flow to both engines. If this is 'necessary' at 907kg (un-modded), why can it be ignored on a modded a/c and only completed at 453kg, or is there a special instruction to carry it out at 907kg on those?
