horlick97-
The CH-47 is actually a fairly fast helo for its size, and a bit faster than a UH-60. The CH-47's rotors are
interleaving in planform, but they have a fair amount of vertical offset with the rear rotor plane being higher. Boeing recently proposed a rather strange compound version of the CH-47 with mast mounted wings above each rotor called
ULOR. Boeing seemd to think they could achieve a >250kt cruise speed with this concept. And then there was the
BV-347 from around 1970, which Boeing actually built and flew. Lastly, fore/aft interleaving rotors is not the only configuration possible. You can also locate the interleaving rotors side by side
as shown here.