| ZB The ZB roundel is known only by two documentary references, but these are so explicit as to leave no doubt that this type of roundel did exist. The first reference, in November 1942, was to Hudsons in the forward area having “all blue roundels on the upper surfaces”. The second reference, in August 1943, indicated that Venturas were arriving at Whenuapai (Auckland) on delivery with the top surface of the wings marked with “just a large blue circle”. By the time of the second reference, however, the Hudson roundels had been modified to ZBP format and it seems that the change had been notified to Hawaii where the Venturas were receiving their New Zealand marks. The apparent origin of the ZB is quite straightforward. In blue for the red centre of the B roundel, the result was quite simply a large blue circle. From this it follows that the ZB was probably restricted to the upper wing surface only, and apart from the two types mentioned, may have also been carried by Kittyhawks of 15 Sqn- but this is unconfirmed and any case would have been only for a very short period before the ZBP was introduced.
In the photo of 1 Sqns Hudson NZ2035 SJ-F parked beside the RAAF Lancaster ED930,
A66-1 in June 1943 the ZB roundel is just discernable on the wings.
ZBP The November 1942 reference to the ZB on the Hudsons was by way of a report on a trial then underway in the forward area in which the roundel was modified by applying a white ring to it. The inside diameter of the ring was given as 12 inches and it’s width as two inches. On the assumption (made with some justification) that the overall diameter of the roundel was 48 inches, we can identify a blue-white-blue roundel of proportional description 40/30. Not much evidence has been found that such a roundel existed – in those exact proportions – but the next stage of evolution to the ZPB leaves little room for doubt. The ZBP would have been used for all wing roundels, upper and lower, on Kittyhawks and Hudsons in the forward area during most of 1943. By late 1943 Venturas would be carrying the ZBP and Catalina wings and quite possibility Dakota wings were similarly marked.
ZC, ZCP Proportional description 60/45, i.e. the same as the British C roundel. Some doubt surrounds the existence of both of these roundels. Appearing primarily on Avenger fuselages, it is quite possible that one or the other did not exist. Some of the Avengers were delivered with standard British markings which at the time were C roundels below the wings,C.1 on the fuselage, and B on the wing upper surfaces. The Avengers first moved to the forward area during January 1944, and had the white bars added before they went. Photographs show the white bars added to roundels of C proportions but with two distinct colours either side of the white ring. On the one hand it seems incongruous that the bars would be added to a red centered roundel; on the other hand there is no evidence to suggest that the centers were repainted blue beforehand (even though these Avengers were brought on charge after the first application of blue centres to the Hudson fuselage roundels and the adoption of blue centred wing roundels generally). Another possibility is that the change was made direct from C to the barred blue/white/blue (the ZPC) in which case neither the ZC or ZCP existed. While further investigation is done a photo of an Avenger in early 1944 with the roundels concerned is attached so you can make up your own mind. Note how the presentation of the code letter has necessitated the deletion of one of the white bars |