The Army B-17s also put in a claim for bombing a "Japanese cruiser" which promptly sank. The "Japanese cruiser" was, in fact, the US submarine, USS Grayling. She "promptly sank", when she crash-dived to avoid the falling bombs. The Army B-17 pilots were also the first ones back to civilization at Honolulu, and covered themselves with glory in bars around the city, the Honolulu Advertiser picked up their stories, and then it went national via radio.
Maybe it would've been better if those B-17s were armed with torpedoes instead, maybe 3 or 4 of them. That would make a nice spread after dropping them. Of course, those big planes would make easy targets too.
A-58 the B17 was not designed to carry torpedos and it would change drastically its capability to try
US arial torpedoes were rather problematic at the time as well. Could the B-17 have flown slow enough to drop them? Early war mk 13's were suppose to be dropped at speeds of less than 110 knots. See: http://www.navweaps.com/Weapons/WTUS_WWII.php The stall speed of the B-17 was around 100 mph but the torpedoes may have required an external carry which would have increased the stall speed. Even without that not much of a safety margin.
I kind of figured that, but I still think it would be neat if they could've. That would have been an impressive sight. A flight of big bombers dropping torpedoes on a line of enemy ships. Ah, if only. If they could've been adapted to do so, who knows. Maybe B-25s and 26s would probably been better at it. What, probably not you say. Fine, be like that.
They were better skip-bombers, which would have been more reliable in both accuracy and detonation. But, that was still some months away. Practicing on the wreck of the SS Pruth.
Still got the only torpedo hit by a US plane at Midway. I wouldn't have wanted to make a daylight torpedo attack on a warship with one though.