I have one of these - the 6-28411 PWC series version from about 2006. Before I open it up to try and solve what I think is a frequent operating issue, I thought I'd ask whether anyone has any experience of fixing this.
The problem is that triggering the remote firing mechanism from a CAB 1 or 2 usually results in at least one of the four missiles not launching. It is usually the first one triggered by the mechanism illustrated below. Sometimes more than one will not launch and I have noticed that to work properly at all it has to be positioned near a power feed to the track. As a result, in my CAB2 this engine is named "MISFIRE."
I have the Army missile sounds boxcar too and the set as a whole is a crowd-pleaser although when it mis-functions you can imagine the joke's on me.
I have looked at the remote mechanism and shown below are what appear to be the main components; essentially I think the coil triggers the plunger (top right) in what I think is much the same way a coil coupler works and the plunger pushes the plastic camshaft (top left) a quarter revolution, which is supposed to release each of the spring-loaded launchers in turn.
The launcher is a separate assembly and a view of one from the bottom is below; I have not figured out yet exactly what in this the camshaft engages but it must be part of each trigger once pulled back to compress the spring:
This appears to be exactly the mechanism used in the original postwar version of this loco, #44, but with a TMCC control board to trigger it. I haven't actually found a parts diagram for these components apart from this dating from about 1960:
A while back there was a thread on these engines and mention made in it (by GRJ) of filing down some of the parts to get reliable operation, but I don't know if that related to the same problem: https://ogrforum.ogaugerr.com/...63#40426816890624363
Final piece of info: using the trigger plunger manually results in each missile firing correctly. Coupled with the need to keep the engine on or very near the track power inputs suggests to me that the coil/plunger lacks enough oomph to move the first trigger. Anyway how to remedy this annoying defect is a puzzle to me.
BTW, I think that Lionel must have dropped the version of this loco catalogued in 2015, which is the main subject of the linked thread. I can't find that model (6-81545) listed anywhere and maybe they could not adapt the old firing mechanism to Legacy control or decided not to?
