As the war went on, travelling by train became increasingly dangerous. NS had to take a variety of measures to protect its trains from increasing attacks by Allied aircraft. From the air, the pilots could not tell the difference between German Wehrmacht trains and civilian trains. In 1944 alone, 276 people died in these attacks, including dozens of NS employees. To avoid becoming potential targets at night, locomotives and carriages were darkened to minimise the light they produced. As soon as Allied fighters were detected, the railways stations concerned were immediately informed by telegraph. Next, a yellow-blue flag was raised to warn railway personnel of a possible air strike. NS was also increasingly confronted with sabotage by the Dutch resistance movement, prompting the Germans to demand a system of ‘rail guards’ in 1942. The task of the rail guard was to inspect the tracks for any abnormalities or irregularities so as to prevent accidents.

Allied air strikes

In the spring of 1943, the railways came under increasing attack from Allied fighters, as part of a strategy to disrupt the transport of German troops and provisions. Steam engines in particular were frequently hit, as were signal boxes, airfields, vessels, roads, cars and buildings. To prevent Allied pilots from discovering driving trains at night, NS took a range of blackout measures. The air strikes had no appreciable effect on the timetable, with train services, including transports on behalf of the Wehrmacht, continuing as usual.

Railway Guard Unit

In addition to being targeted by Allied fighters, the railways were also the subject of sabotage attacks by Dutch resistance groups. The saboteurs tried to disrupt German army transports, for example by detonating explosives or loosening bolts on the rail tracks. In response, the Germans ordered the establishment of a Railway Guard Corps in 1942. Around two thousand men from outside NS were enlisted for this purpose. The Railway Guard Corps was funded by the Dutch government. Supervised by NS staff, the railway guards inspected the main railway sections eight times a day, with each guard covering more than 30 kilometres a day. During the first seven months after the establishment of the first Railway Guard unit alone, 16 guards were killed in accidents and air raids.