Possible Clues:

• Steps inside
• Steps indoors
• This may get you up to the end of the street where there's a windbag
• Flight commotion about a piece of luggage
• Leaders in space technology expose incident in flight
• Building feature that fits in well
• What you need if you're on the up and up
• This puzzle has a secret one, starting with the third letter of 4-Down
• A group of linked canal locks
• Flight succeeded by landing?