Technical information: I have been in contact with a very knowledgeable aviation engineer in the USA. His name is Norman Hawk, who has had a long interest in Harriet and the resultant tragedy and why it happened. His correspondence is below:
Martin, I apologize for my slow response to your inquiry. Although I am retired, I find myself challenged for more time. I am building a Sonex airplane in my garage, add to that family, social, and medical matters, and that means time is short!
I have a Bachelor's degree and two advanced degrees in Aerospace Engineering from the University of Michigan. I have worked for Boeing, the Glenn L. Martin Company, University of Michigan, Williams International, and General Motors Tech Center. I retired in 1997.
I propose you could publish, if you wish.
I have found a copy of the Harriet Quimby Research Conference Journal, volume four, 1998. and could photocopy my paper for you. However, I imagine a digital version would be cleaner and more useful to you, so I will continue to dig for it.
Please acknowledge receipt of this email, and provide any comments or questions you may have. I would be interested in hearing your Bleriot owner's comments, if any. I have seen a very few Bleriots, and they all have had the horizontal stabilizer which splits at mid-span. I suspect this might be a more robust tail in terms of pulling out of a dive.
I would like to add that Barnaby Wainfain, a well-known and respected Aero Engineer (developer of the "facet plane"), wrote in the the magazine Kitplanes that the Bleriot dive was caused by the wing.
I see this as a confirmation of my earlier analysis, and a final answer to all those experts who chose the lifting tail as the basic cause of diving.
I wish the very best to all you folks who honor Harriet's accompllishments . It is a tough but rewarding job!
Sincere regards, Norman Hawk