What does it fix? My work internet filters the main HTC website, but not the forums. 
# Fixed a memory allocation bug that caused offline crashes.
# Fixed some collision issues with trees.
# Smoke puffs from gun muzzles are now turned off when weapon effects are disabled in the graphic preferences menu. If you see a significant frame rate reduction in certain planes or vehicles while firing, this can help you a lot.
# Fixed a bug that caused blast damage to hit the wrong area of the plane.
# Fixed a bug that caused the P-39Q’s gun pods and bomb rack to be visible when they weren’t loaded.
# The D3A had different mismatched bomb shapes on each wing that didn’t destroy correctly.
# Fixed a bug that caused enemy icons not to display through the tower window.
# Fixed minor graphic sorting issues on the C47, Ki-61, Mosquito, Ar 234, Lancaster, T-34, and medium airfield roads.
# Fixed some damage graphic bugs on the FM2/F4F, Ki-61, B5N, IL-2, Bf 110’s, A20/Boston, F4U-1C, and P-51B.
# Fixed a bug that caused P-47 gear to not be visible from longer distances.
# Fixed some instrument needles on the Spit XIV that were not properly centered on the gauges.
# Fixed some issues related to running consecutive practice missions that caused a wide variety of weird symptoms- invisible drones, incorrect mission timings, etc.
# Fixed an offline mission bug that caused you to hear pings taken by friendly wingmen.
# Ostwind turret now allows for a slight amount of depression.
