Dave,
Just wait until Lu decides to hate the CarterCopter, then we'll watch you jump! His mindless diatribes are worthless, and his ability to worm away from what he posts makes him quite useless except as a gadfly.
This thread was hijacked by him when he asserted that a certain helo was not safe, and not properly certified, and he misquoted the regs to make his point. His string of unproven and unprovable slanders on that helo are a shame.
You can try to find good in that, because you seek good in all people, but such charity is unearned when Lu fails to learn anything from those who post facts. His kind of drivel is what makes the internet such a difficult place, and is the death knell of web sites.
Just because he confused you long enough to reverse your understanding of delta three (he has NEVER understood it, Dave!) does not mean he adds value.