Madman said:
A question popped into my mind recently.
Did the torpedo bomber immediately go away after WWII? If so why?
Or did that aircraft type hang around for a while and then fade away?
I understand other weapon types made it useless sometime after WWII but it sure seems like in my mind that it just vanished in late 45.
If you mean USN torpedo bombers (TBF/TBM, etc.), they actually started going away before WW2 (at least planning for replacements of various aircraft). And I apologize for the Wikipedia links, but they're actually somewhat helpful in this instance.

In short (?), in 1941, the navy requested a replacement for the SBD and SB2C capable of dive bombing, as well as being able to carry torpedoes. This was the XSB2D-1. It was too heavy, was very complex, and was never ordered into production.
In 1943, the navy issued a request for proposals for similar high-powered multi-bombing-roll aircraft. The new designation would be BTx, instead of SBx or TBx. Several manufacturers developed prototypes.
Douglas reworked the XSB2D-1 into the
BTD-1 Destroyer. Curtiss developed the
XBTC. Martin developed the
BTM Mauler. Kaiser-Fleetwings developed the
XBTK. Ed Heinemann at Douglas developed a second BTx aircraft, and it was designated the
XBT2D-1 Skyraider. I may have missed a few, too.
Most of these flew and were evaluated during the war, and a few were ordered into production, mainly the BTM and BT2D. All were single engine and single seat aircraft.
During the war, with the destruction of the Japanese fleet, the need for aerial launched torpedoes greatly reduced. For example,
Essex's VT-83 launched a total of 15 torpedoes during their combat cruise from mid-March to mid-August 1945. These 15 were launched at
Yamato and her escorts.
And with the destruction of the Japanese air forces and superb escorting fighters, the need for a backseat radioman gunner went away, and was deemed a liability by most squadrons. On the carriers in combat, both the VB and VT squadrons had near identical missions, despite their different mission profiles.
The SBD, SB2C, and TBF/TBM were obsolete by 1945, and some version(s) of the BT were their pending replacements. In 1947 the navy changed designations, and the SBs, TBs, and BTx went away, and were replaced by one: Ax. The BTM Mauler became the AM-1 Mauler, and the BT2D Skyraider became the AD-1 (through -6, plus others) Skyraider.
So, the fleet had torpedo capability after WW2, there was just minimal need for it. According to Wikipedia (and from what I know), the last torpedo attack in history was on the Hwacheon Dam in Korea on 1 May 1951, by the AD Skyraiders of VA-195. Of course, the AD was redesignated A-1 in 1962.
So, a carrier-based attack aircraft capable of carrying torpedoes faded away after the A-1 Skyraider was retired from carriers in the 1960s.

HTH