(Sheepishly) My only reference is a talk by Bryan Cantrill[1] where he states that an exec at a hard-drive manufacturer stated it was ".8 nanometers". I will tr

(Sheepishly) My only reference is a talk by Bryan Cantrill[1] where he states that an exec at a hard-drive manufacturer stated it was ".8 nanometers". I will try to find a better source than that. EDIT: There is a paper from 2016 which did an analysis in the difference in the flying height of the head during different operations, and it was measured in Angstroms[2]. I couldn't find one that actually gives a precise value of the flying height. There is a 2011 paper which states that some system they were testing allowed for 4-9 nm flying heights[3] which is about half-an-order-of-magnitude larger than the claim -- but that's already 7 years old. [1]: https://youtu.be/fE2KDzZaxvE?t=1551 https://youtu.be/fE2KDzZaxvE?t=1551 [2]: http://iieng.org/images/proceedings_pdf/E0116009.pdf http://iieng.org/images/proceedings_pdf/E0116009.pdf [3]: http://maeresearch.ucsd.edu/callafon/publications/2011/UweIEEETonM.pdf http://maeresearch.ucsd.edu/callafon/publications/2011/UweIE...