"There are two drain masts. The one just aft of the port wheel-well is shared with the hydraulic reservoir vent and is a shrouded line enclosing the APU fuel supply line, this collects any leakage of fuel into the shroud which can be drained when a stop cork is pushed up in the wheel-well. If fuel drains when the stop cork is pushed, it indicates a leak in the APU fuel line".
This is an excerpt from this link: http://www.b737.org.uk/apu.htm
a) I am wondering if this excerpt is valid for the B737 NG, the classic, or both?
b) If the B737 NG is fitted with the "stop cork" (mentioned in the excerpt), where the leakage of the fuel goes in flight if there is a leak in the APU fuel line?
c) Are other aircraft (Boeing, Airbus, Bombardier, Embraer,...) fitted with APU fuel drain mast ? Is it similar to the B737 ?