In the photograph posted by RYFQB, (thank you for this) there is an abundance of marking to the lower (or higher, as it would have been originally) part of the VS which is directly in line with the missing HS.
What is the likelihood of the VS having failed first, and then being hit by a detaching HS?
Can we think of any other possible cause for the scraping and so on to this area?
Link:
http://d3lp4xedbqa8a5.cloudfront.net...nai-flight.jpg
Also why the 'double line' scrapes to this segment? I have not seen those before. (The two sets of parallel lines on the VS going horizontally)