Someone know how the Landesonde system on this Aircraft worked ?

Hello ayf,

A cable of about 40 m length was led from a shaft inclined 30° to the rear. The end of the cable was weighted with a metal chain. When the aircraft descended below a certain altitude the chain touched the water surface, changing the angle of the cable. This activated a contact Switch which caused a warning light to illuminate.

Best regards
Peter W. Cohausz

Was this to give the crew time to sit down and fasten before the aircraft entred the sea surface ?
Witch aircraft types used this system ?
Regards ayf.

Mostly on flying boats as Do 18 or Do 26.

Regards
Peter