As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT FLIGHT LEVEL 390, THE AIRCRAFT EXPERIENCED A JOLT AND THE LANDING GEAR UNLOCK LIGHT ILLUMINATED. THE PROBLEM WAS CAUSED BY THE NOSE LANDING GEAR DROPPING OUT OF THE UPLOCK HOOK. IT WAS DETERMINED THAT THE NOSE GEAR STRUT WAS OVER EXTENDED. THE NOSE GEAR WAS DISASSEMBLED AND THE LOWER ORIFICE CAP WAS FOUND TO BE PARTIALLY UNSCREWED. THE SAME PROBLEM HAS OCCURRED ON OTHER AIRCRAFT OF THIS MODEL.