They should be SAP as the D in SD stands for Dickwand = litterally "thick wall". A 500kg SD bomb has much less HE filling than it's SC counterpart, between 75 and 180kg depending on variant, compared to the ~250kg of a SC bomb. And this is why it was taking up less volume in the bomb bay.
This bomb was often used against semi-hard targets which required some additional penetration like multi-story factory buildings, iron structures and so on. The SD-500E variant could penetrate 50mm of armour steel.
Sorry for the very late response to this, I lost track of it.
Well perhaps the D does stand for thick wall, I do seem to get my SC and SD mixed up at times, but I did double check this one and the SD is smaller in size than the SC, while still maintaining almost the same explosive content.
SC500:
Info:
http://www.warbirdsresourcegroup.org/LRG/sc500.htmlImage:
SD500:
Info:
http://www.warbirdsresourcegroup.org/LRG/sd500.htmImage:
The SD has approx 200kg of filling for a total 535kg weight (metal casing included) while the SC has 220kg of filling for a total of 500kg weight (metal casing included). What's more the SD500 has a smaller diameter and fins that are no larger than the body itself, while the SC500 fins extend out from the body noticably. It wasn't that the bombs were too big, just that the fins were. (Similar to the F-22 and F35 planes of today, they need AIM-120Cs, which have smaller fins so they fit inside the launch bays)
I also have a quote from one publication (which I've posted before on Me410 threads) which I've posted before that says explicitly the SC500 required the bomb bay doors to be ajar slightly, while the SD500 would fit with them closed.
This is a bomb with just about the same explosive content as the SC500, but a narrower set of fins and different body shape allowing it to fit inside the bomb bay. It wasn't a cluster bomb, and it wasn't an armor piercing bomb. It was a different body.
That's the bomb that AH should model for it. It's the 500kg bomb most likely to have been loaded on a 410.
