touch-and-go 
adjective
(Of an outcome, especially one that is desired) possible but very uncertain: it was touch-and-go whether she could reach the pram before it overturned...
- Do you anticipate any additional touch-and-go maneuvers?
- Paddling on Lake Athabasca is a bumpy, touch-and-go affair.
- Now it seems like he probably will, though it's still very touch-and-go.
Synonyms
uncertain, unsure, unclear, dubious, tight, delicate;
sticky, tricky, precarious, risky, in jeopardy, in danger, hazardous, dangerous, critical, unsafe, treacherous, suspenseful, cliffhanging, on thin ice, hanging by a thread
informal hairy
British informal dodgy
noun (plural touch-and-goes)
A manoeuvre in which an aircraft touches the ground as in landing and immediately takes off again: I tried a few touch-and-goes...
- He did 10 touch-and-goes on his next landing - I've never seen an airplane bounce so high so much, so far.
- Thoroughly warm the aircraft engine by taking the plane up for some touch-and-goes or a quick trip to a local airport for the usual high-cholesterol breakfast.
- For example, a plane that makes many flights or touch-and-goes during the year should have its landing gear lubricated.
