 WLS radio announcer Herb Morrison was present at the scene of the  Hindenburg crash, along with his engineer Charlie Nehlsen, and  recorded an eyewitness account of the unfolding tragedy. This audio  clip can be heard at the end of the film. However, Nehlsens  recorder was running a bit slow, so that when the recording is  played back at normal speed, the pitch of Morrisons real speaking  voice is raised slightly. Also note that a slight cracking is  audible at one point during the recording. This was caused by the  shockwave of the explosion reaching the recorder just after Morrison  shouts "Its burst into flames!"