Both developments, the Nord 510 and the Kiebitz, started during 1966
and the Kiebitz II should carry the Orphée radar, the same type, as in
the Nord 510. But I couldn't find a clue, that both designs were competing.
there was no connection between the Nord N.510 and Dornier
Kiebitz as I search,but here is anther design;
the Nord N.511,it was developed from N.510 to meet the latest
requirements of a French "observation by helicopter" program
in the late of 1960s,this version was tethered to the lorry by
only a single cable.It should permit flights to much greater heights,
up to 3000 ft (1,000 m),and the N.510 to 1000 ft (300 m).