During the crash of the Hindenburg, a piano is seen sliding across the lounge. In reality, the piano was removed from the Hindenburg before the 1937 season, and therefore was not present during the crash in New Jersey.
Semi-automatic pistols were invented in 1892, becoming commercially successful in 1894, and used almost immediately by some armies around the world. The design of the Colt M1911 is the basis of many "modern" semi-automatic pistols, was in use by US armed forces as of 1911, years before WWI, making the statement about modern weapons not so modern.
When the Hindenburg initially crashes in the original timeline, the explosion occurred just forward of the port-side fin, not on the top of the ship as the shown in the episode.
When Lucy describes the crash of the Hindenburg at 16 minutes 30 seconds into the episode, she says that 2,000 cubic litres of hydrogen burn.
Litres are a unit of volume, and one litre is 1000 cubic centimetres. So saying cubic litres is nonsensical.
Litres are a unit of volume, and one litre is 1000 cubic centimetres. So saying cubic litres is nonsensical.
The yellow flame as the dirigible catches fire is historical although you may wonder why the hydrogen bags burn yellow and not blue - but the spark is from the mooring mast which money presumably could not buy.
When Lucy answers her phone at the end of the episode, you can still see the accept/decline screen on her phone.