Michael,
Actually these matters have been up here and there a number of times (use the new search faciliy and see for yourself). I am not a boat designer, so just have to draw on my practical experience. To sum up, here are seven issues I can think of around a mast:
1. Windage when sailing.
2. Windage when anchoring.
3. Windage when doing harbour manoeuvres (under motor)
4. Static moment sideways (stiff-tender)
5. Static moment fore and aft (nose/tail-heaviness)
6. Dynamic moment, inertia in rollplane.
7. Dynamic moment, inertia in pitchplane (hobby-horsing)
#1: Of course we wish that our masts should have a tiny diameter to keep drag low. I have used thick wooden masts on my two first junks. On my 29’/3ton Johanna, the 10.6m mast had a “sail area” of 1.6m2. That could definitely be felt when we were tacking with a deeply reefed sail. Still, I don’t think it ever widened the tacking angle with much more than about 10°. Head sea (and averse tides) does a lot more to slow down progress to windward.
#2: Honestly, I haven’t done much anchoring from the bow with my junks (..much easier to drop the hook over the stern here, since there is hardly any tidal currents...). My Malena surely sailed around badly when being anchored at the bow. Still I think it should be possible to dampen the swing, for instance by adding an asymmetric bridle, as shown on the sketch below (Yawl rigs were popular on small gaffrigged yachts, as the mizzen could be used as a riding sail)
![](/resources/MemberAlbums/2773509/Arne's%20Sketches/thumbnail/20050212%20anchoring%20with%20an%20offset%20bridle.gif)
#3: Doing harbour manoeuvres, that is, backing out of the berth and heading in the preferred direction, in strong winds, surely can be a challenge: The thinner and shorter the masts, the smaller the problems. In addition, I find that having a steerable outboard engine, makes these critical manoeuvres a lot easier. At least there is no bowsprit around...
#4: The added weight of the mast robs a bit stability, but I have found that as long as the mast does not add more than 3% ( better with 2.5...) to the boat’s displacement, one needs not worry about its impact on stability.
#5: Putting a stout mast in the fore section of a boat surely will make her more nose-heavy. On Malena, Johanna and Ingeborg I either removed or just emptied the water tanks there, and this restored balance.
#6: The mast’s inertia in the roll plane simply slows down the roll rate (compared to with a lighter mast or no mast). This makes the boat more comfortable in some conditions (short inshore waves and swell from ferries etc) but tends to get the boat in resonance with bigger sea waves. This is the same for all sail rigs.
#7: Inertia in the pitch plane. Again, if the mast is kept at moderate length and weight, this seems to not be an overwhelming problem. After all, pitch plane inertia of the boat itself will be the main contributor here. What you can do (and which racing crews do) to minimise pitching (“pitch radius”), is to move heavy weights inside the central third of the boat: Stuff like anchors, fuel and water. And remember; hundreds of sloop-rigged junks plus Bermuda- and Gaff-rigged cats are already sailing around and coping well, most of them.
In haste - hope some of this makes sense...
Arne