An aeronautical engineer was designing a plane that would
be the fasted flying plane the world had ever seen.
However, the engineer was struggling with one design
problem. Every time they test flew the aircraft the
wings would fly off. The engineer tried different wing
sizes, angles, mounting locations and shapes. A different
shape to the fuselage was also tried and failed. Test after test
had the same result; the wings would fly off.
One day the engineer was standing alone in the hanger just staring at the plane with a puzzled look on his face. A janitor was sweeping the hanger and casually swept his way over to the engineer and said, “So...you're having trouble with the wings coming off your plane?” The engineering replied with a simple, “Yah”. The janitor paused briefly and said, “Why don't you try perorating the wings next to the fuselage?” At that he continued sweeping and swept away from the plane.
The engineer ignored the suggestion, but then thought, “what do I have to lose? I've tried everything else. Maybe the air will go through the holes.” So...first they perforated the end of the wings. The plane was put in the wind tunnel and the wings stayed on. But there was a lot of flutter and instability. Next, they perforated the middle of the wings. Put it back in the wind tunnel and the wings not only stayed on but were a-bit more stable. Then they perforated the wings next to the fuselage. They put it in the wind tunnel and not only did the wings stay on, but they were solid with no flutter or abnormal movement. A test flight was scheduled and the plane was flown around the world faster than any other plane had ever flown. It was able to break the sound barrier without creating a sonic boom. They landed in various cities around the world showcasing the achievement to the high acclaim of every nation.
Days later the team returned to their home hanger. The engineer was standing in the hanger marveling at his achievement with a huge smile on his face. It's then that he saw the janitor sweeping at the far end of the hanger. He ran over to the janitor, grabbed him, hugged him, shook his hand, patted him on the back and said, “How in the world did you know that perforating the wings would solve my problem?” The janitor took the stub of a cigar from his mouth and said, “Well...I don't know much about planes and wings and all that stuff, but what I do know is this. Every time I pull toilet paper from the roll, it never tears at the perforated end.”
