Wow. I did that drawing in 1994, and ye old memory isn't what it used to be. I remember that Bob Browning, the CG Historian (then and now), provided me with at least two sheets of drawings that were labeled in German and had the name Horst Wessel on them. On that basis I concluded that they could be relied upon. Those two sheets obviously did not constitute a full set of plans for the ship. I don't recall exactly what was on them; I think I remember an inboard profile and some cross sections. I think there also may have been one sheet showing a couple of rigging details - obviously one sheet from a rather large series. Bob Browning and I had the impression that these were the only plans of the Horst Wessel that had survived the war. That may, however, have been an incorrect assumption on our part. The bottom line was that they were the only German drawings in the CG Historian's Office's collection at that time. (I guess it's possible that something else has turned up since then.) I don't remember what, if any, numbers were on them.
Then there were several sheets that had been prepared by Coast Guard draftsmen fairly recently. I recall in particular a combination above-waterline outboard profile and sail plan (reproduced at, I think, 1/96, so the drawing was pretty huge). As I remember the hull outline on that one matched the German version (which was on a considerably smaller scale, I think) pretty well. But I had my doubts about the reliability of that modern CG drawing. Specifically, the draftsman took some pains to indicate a series of "eyebrows" over all the portholes in the hull. (I can testify from experience that, even on a relatively large scale like that, drawing all those eyebrows, and getting them to look symmetrical and identical, by hand - in the days before CADD - was a bit of a challenge.) The problem is that, so far as I can tell, the Horst Wessel/Eagle has never had such fittings over her portholes. Why the draftsman put them there I have no idea, and the detail isn't particularly important, but it has to make one wonder whether he looked at the actual ship. I don't remember what date appeared on it; I seem to have a vague recollection that it showed the ship in her sixties configuration, but I could well be wrong about that.
Then there was an enormous, scantily-detailed sheet called a "docking plan," which apparently was drawn in conjunction with the preparation of a drydock for one of the ship's periodic major overhauls. This one certainly looked as though it had been drawn on the basis of measurements taken directly from the ship. It consisted of a simple profile and a very few details that would be relevant to the people responsible for overseeing the ship's transit into the drydock. Extremely basic but, I think, entirely reliable.
My drawing represents an attempt to reconcile all those earlier efforts - and the hundred or so photos I took myself on board the ship (the one time during the project when I was able to catch up with her). As I mentioned in that other Forum thread, I had about an hour and a half on board her in Baltimore, sometime in the summer of 1994. I took a draft of the drawing I'd been working on with me, and got as much input as time allowed from the captain, Patrick Spillman, and the boatswain, Keith Raitsch. (I've probably misspelled both those gentlemen; I hope they'll forgive me.) Mr. Raitsch was particularly helpful; he'd done a detailed study of the changes the ship had undergone over the years and, I think, had been instrumental in the decision to restore the double-spanker rig on the mizzen mast.
The bottom line regarding the Underhill plans is that, for my particular purposes, they were just about useless. Don't get me wrong; I'm a big admirer of Underhill - as both a draftsman and a ship modeler. But those drawings - as he himself was careful to explain in the text of the book in which they originally appeared - show the Horst Wessel's semi-sister, the Gorch Fock. The Horst Wessel/Eagle is about 24 feet longer. And the drawings date from the 1950s. The job that had been given me was to draw the ship in her then-current (1994) configuration. Practically every piece of deck furniture had been altered by then in one way or another. The boat complement was completely different, a deckhouse had been added to the break of the quarterdeck, all sorts of changes had been made to the spars, etc., etc. In 1994 she'd recently come out of yet another major overhaul, which had seen, among other things, the restoration of the double spanker. I took an admiring look at the Underhill drawings, concluded that she'd been a beautiful ship back in those days, and worked from the sources Bob Browning gave me.
I just remembered on other source I consulted. I drove up to Newport News and looked the ship up in the files of the library at the Mariners' Museum (with which I was still on speaking terms at that time; I haven't been since). I'd figured that since Bill Wilkinson, director of the museum when I worked there in the early eighties, was one of the world's biggest USCG enthusiasts, something worthwhile might be there - and I was right. The library had a big, fat folder of 8x10 black-and-white photos that had, if I remember correctly, been taken sometime in the fifties, and showed just about every external feature of the ship. For my purposes they didn't help a lot, but if you're trying to nail down her fifties configuration they'd be near-ideal. Just how to gain access to them I don't know; the MM has become notoriously difficult in that regard lately.
That's about all I can remember about the project at the moment. Hope it helps a little.