Jan,
Have a look at
https://www.moosburg.org/info/tour/kippe.html
This is what is said at the beginning of the page - "The airfield on the dump
The "Kippe" is located on the southeastern edge of Moosburg near the mouth of the Amper crossing canal into the Isar. It borders the floodplain landscape. It owes its name to the construction of the canal in 1920, the excavation of which was dumped there.
The area was used in 1962 to create an airfield for the Moosburg Aviation Club. The grass runway, which is surrounded by trees, is 690 meters long and can even be used by 900 meters if necessary.
Since Munich Airport opened, only aircraft from the flying club have been allowed to take off and land on the dump. At the association's request, the South Air Office occasionally issues special permits for third-party aircraft."
PS I cannot find any reference to Moosburg or "Kippe" in Luftwaffe Airfields 1935-45 Germany (1937 Borders) By Henry L. deZeng IV.