I thought a moment and said, "That sounds like it could have been a mechanical malfunction."

One of them didn't shoot (maybe mechanical malfunction, but I doubt it).

He said the plane showed no signs of mechanical malfunction.

Due to mechanical malfunctions both athletes did not finish the road race.

Some mechanical malfunctions are caused by poor design and cannot easily be avoided.

He added: "We found no evidence of a mechanical malfunction.

"Now, we have to find out whether the gun went off because of any mechanical malfunction or human error."

Some, it said, were caused by human error or mechanical malfunctions.

But by itself the mechanical malfunction would not have been enough to cause the fatalities.

God forbid some mechanical malfunction should end that relationship just in the promise of a new beginning!