Copyright searches were done in both artwork and motion pictures for renewals from Wide World and its successor company, Associated Press, as well as Pathe. In addition, these categories were searched for "Hindenburg". There were no results for any of these searches for the years 1964 and 1965. There's no evidence that copyright continues to be claimed on this material.
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.
{{Information |Description=Composite of four photos taken after the crash of the airship Hindenburg. |Source=[http://www.ebay.com/itm/VINTAGE-1937-Hindenburg-VERY-RARE-Original-Contact-4-Image-Sequence-Photo-/351069354616?pt=Art_Photo_Images&hash=item5...