I was unaware of the near free-fall collapse of World Trade Center Building No. 7, which had almost twice as many stories as any Utah building. Without being hit by an airplane, it collapsed into its own basement as fast as a bowling ball dropped from the sky.

From my engineer's perspective, these collapses cannot be explained by simple pancaking theories based on burning jet-fuel and office furnishings. Momentum and energy dynamics suggest that any collapses would be considerably slower than free-fall, and not symmetrically straight down.

My search led to watching Dr. Steven Jones, a Brigham Young University physics professor, present his paper: "Why did the WTC Buildings Completely Collapse?" and reading it. He seems sincere and mild-mannered like Griffin. Jones' analysis backs my reasoning that jet fuel and office fires alone could not cause the observed collapses.

Many engineers have accepted the official versions of the 9/11 events, so his unthinkable conclusions concern me.

Griffin's book lead me to review the WTC collapses, which raises this perplexing dilemma: The observed collapses are unexplainable without resorting to conclusions that are unthinkable.

For the good of America and public safety, an open, impartial inquiry into 9/11 is needed.

Jack Keller

Logan