I listed it that way, with a "?" mark, in order to note it for investigation, not that I think or know that radar was or was not used. I always try to do that in my BB UNK case listings. I found it strange that all the witnesses, who worked at an Air Force ADC RADAR station should have this spectacular daylight sighting at the RADAR site for 3-5 minutes (I don't believe the one witness estimate of 5-10 mins) and NO ONE in their statement mentioned attempting to alert radar controllers to check for unidentified targets. If the sighting had only been for a few seconds then there would not have been enough time, come and gone, and it might be understandable, but 3-5 mins??? Also strange is that not one AF witness mentioned what their position was at the 768th AC&W Sq -- did any of them happen to be radar CONTROLLERS??? If one or more controllers had been witnesses then their seeming failure to check the radar would stick out even more.
There is no initial electronic teletype report on or about April 13 in the file or mentioned in the AIIR to ADC which manages to avoid bringing up the glaringly obvious fact this was a RADAR station and yet nothing is mentioned about checking the radar! (There is only Ruppelt's teletype query weeks later and the Moriarty station's teletype reply.)
What I'm suggesting is that for some reason a separate classified RADAR report was submitted to ADC and all mention of it and any mention of radar at all was carefully avoided for some reason. Only when pointedly asked about radar by Ruppelt was there a response discussing radar (in the alleged negative).
IF (a BIG if) there was a classified radar report, what kinds of things might have caused the secrecy? Well imagine if IFF had been involved -- it could have provoked a highly classified investigation and response with orders to low-ranking AF personnel to not even mention radar let alone IFF. It could have been something else entirely. I just mention IFF as one example where one could see how a confounding and peculiar secrecy could be slapped down on a case. Responses like this might be very inconsistent and vary from time to place, and not automatically imposed the same way every time.