Possible Clues:

• Upstairs passage
• Level area between stair flights
• Fish nets with stairs section
• In two ways the end of a flight?
• A down-to-earth passage
• Airport activity created by minor crash on network
• Disembarkation
• One of those in The Upper House, in 15 across and in Government?
• End of flight, outdoors and in
• Area at top of stairs