Piper - I don't know what your relevant experience is, nor what you're testing - but DAR and I have both spent significant portions of our lives doing that sort of testing for a living. I'm certainly very happy to share what wisdom I have, and I've never known him to be unwilling to open up and share his experience either.
Here's one way of doing take-off and landing distances, although nowadays we'd mostly use recording GPS...
http://bura.brunel.ac.uk/bitstream/2...oJ%20final.pdf
If you want to email be at boffin at engineer dot com, I'd be happy to set up a 3-way email conversation.
G