Exactly. The reason I brought it up is cause there has been alot of talk recently about "auto ck6 calls" and people wanting to get rid of the check 6 feature we have now. People might not know that some WW2 late war aircraft actually had these "check 6" radar antennae. Personally, I think if it was on the plane, and you can prove it, HTC might be willing to look into adding it as a feature.
My book only shows that it was there, not ranges and such though. Would be interesting to know how far back and to what angles it would detect aircraft. I'm pretty sure it was a reasonably short distance.