SB2C-4E Helldiver radar operations

[Johnny .45]

I see that the SB2C-4E was fitted with AN/APS-4 radar, and was curious what a daytime fair-weather aircraft needed with radar anyway. I don't find any mentions of them being used on night ops, and the weather was rarely bad in the Pacific, even if they were willing to launch a/c into bad weather. So was the radar used simply to expand search range during daylight? Could it "see" targets over the horizon, maybe pick up small targets like a periscope better? The APS-4 was a small but relatively effective radar set, but it was capable of air-intercept use as well. I'd just always thought of radar as a night/bad weather aid, but it must have been used for daylight searches as often as night searches. Unless they did fly Helldivers and Avengers at night?

For example, here is an excellent bunch of information on the APS-4 and radar in general (HyperWar: Tactical Uses of Radar in Aircraft (RADTWOA) [Part II]), but it only talks as if it was used to improve tracking and navigation in poor visibility. When did Helldivers fly in poor visibility. It DOES give good range information, which would be a help.

 

[davebender]

I think you answered your own question.

More then one WWII era USN squadron got lost and had to ditch when they ran out of fuel. Having a pathfinder aircraft to accompany an airstrike increases the chance for finding the target and then finding your own CV.

 

[oldcrowcv63]

Johnny, the advent to Radar provided a much improved (over the human eye) navigation and target detection tool even in the best weather. Visibility over the ocean can be problematic even under what are nominally considered to be good conditions. There is a frequent daytime natural phenomena known as maritime haze caused by evaporating water that severely limits visibility even from a/c at altitude. The ocean is a big place and while visibility may extend to 10's of km (miles), there may be scattered clouds and haze that prevents identifying high value targets. Remember an aircrew is looking for a target typically painted 'haze gray' which doesn't help. The ships more visible wake is often the first indication one gets of its presence. I have been on more maritime search missions than I can count and unless we were covering a shipping lane, it was never easy, even with radar. Without radar, these maritime patrol mission searches would have been virtually impossible. In the old days, before Radar, nearly an entire squadron was carried and deployed to perform a maritime search. As radar became more available, progressively fewer aircraft were required as radar performance improved.