A group of professors were called to board a plane.
When the doors closed and the plane is about to take off, all the professors were informed that this plane was designed and built by their students. All the professors rush toward the plane doors, trying to escape and survive on their own with exception of one professor who remained seated, full of confidence and calmness.
Someone's asked him why you're not escaping the plane.
The professor answered him with confidence, they are our students.
Next Question: Are you sure that you taught them well?
Professor replied quietly: I'm Sure it won't fly.