17 replies to this topic

[gregoryk]

Some people do crosswords to pass the time, as do I, but I also work statistics to see what is the likely chance of something happening. Having been involved in a collision with another RN cruiser in only my second GQ game, I decided to figure the chance of that happening when two ships are within 500yds of each other. The least chance, when two ships are "trying to avoid," is p=.444. This seems a bit high for intentionally avoiding vessels. By comparison, if one ship is attempting to ram, it does so with p=.67.Does anyone have any info about whether these may be high probabilities?Cheers,Gregory

[Radek Gozdek]

imho only bad weather, night, and sudden machinery damage should cause chance of collision.

[gregoryk]

ragozd wrote:

imho only bad weather, night, and sudden machinery damage should cause chance of collision.

Well, no, since ships on daylight peacetime maneuvers would occasionally collide. Add close formations, high speeds, combat, smoke from guns and stacks, confused communications, and maybe higher seas than usual. It is no wonder that one's own ships once in awhile "bumped." Moving large metal objects, or even small fiberglass ones, through a dynamic medium, i.e., water, guided by groups of people is not nearly as easy as people think. See "Now Hear This" on pages 1—2,3 for a very good description.Gregory

[Dave Franklin]

I agree the chance for inadvertant collisions, where both sides are trying to avoid, seems too high.My first thought had been to either a) make it so the CDRs had to equal each other, b) use a D12 instead of a D6, or c) both.On the other hand, real ship captains are much more reluctant to get their real ships close to other real ships where a real collision might take place than a gamer is with little model ships. Which makes me wonder if the somewhat easy likelyhood is designed to induce a behavior adjustment in said gamer.

[Lonnie Gill]

Yes, this rule is intended to induce reasonable behaviour during game maneuvering. You can, of course, customize the game as you want, but I'd offer a few thoughts.First, the probability analysis mentioned is incomplete. If you keep your ships more than 500 yds apart, the collision probability is exactly zero. [hint] Then, maneuvering two large large objects, each 100 - 200 yds long, with tons of inerita within 500 yds of each other is always a situation fraught with tension. Further, experiences racing sailboats has again and again shown how often the other guy does just the opposite of what you thought he'd do in close quarters. Then, suddenly, it's too late.So, don't want that problem; stand clear. When ships commanded by someone else get close, having both secretly plot can lead to maneuvers with a dose of reality you hadn't attended.Finally, I wouldn't recommend you start talking probabilities at your courtsmartial when you get back to port. Explaining why this supersedes good seamanship ain't gone'a answer very often.LONNIE

[gregoryk]

I admit that gamers should be dissuaded from taking unnecessary or unrealistic risks, so from that perspective, it certainly works.At the risk of being court-martialed, the reason I brought this up is because the chance of colliding seems unrealistically high, and it also bears an uncomfortable familiarness to a complaint about the earlier versions of GQ, that it was too easy to use ramming as a tactic. Here is the breakdown:[ul]current:— trying to avoid p= .444— trying to ram p= .583— moving ship trying to avoid stationary ship p= .33possible change, using d12 and keeping the "if CDR's within one" provision for avoiding vessels:— trying to avoid p= .236— trying to ram p=.54— moving ship trying to avoid stationary ship p= .167[/ul]For those who wish a slightly less bumperish game.Gregory

[Lonnie Gill]

There's not a risk of court martial for a different view on this quarter deck. No one person has all the good ideas - especially those only semi-omnipotent, such as your humble designer. So, let's explore these views. That's how we'll make the game better.Greg has proposed using D12s rather than D6s to provide a wider probability spread between different encounter situations than the legacy GQ approach with D6s. That was focused on encouraging good seamanship.Which do you prefer?LONNIE

[William MacGillivray]

lonnie wrote:

Greg has proposed using D12s rather than D6s to provide a wider probability spread between different encounter situations than the legacy GQ approach with D6s. That was focused on encouraging good seamanship.Which do you prefer?LONNIE

Before I give my view, can I just something clarified?In the game, if a formation is initially spaced at x yards, do they remain spaced at x yards even if they turn in succession? (ie, the ships' captains are assumed to slow down or speed up to keep station)Or, if they are spaced at x yards and the lead ship turns (so 'losing' half its speed in the turn), does the next ship close up because its speed has to remain at the formation's speed?If the latter, then we have found that, unless the initial formation spacing is over 700 or 800 yards, it is very easy for ships in a single line ahead formation to close to within 500 yards any time a turn in succession is made.

[Cpt M]

In the game, if a formation is initially spaced at x yards, do they remain spaced at x yards even if they turn in succession? (ie, the ships' captains are assumed to slow down or speed up to keep station)Or, if they are spaced at x yards and the lead ship turns (so 'losing' half its speed in the turn), does the next ship close up because its speed has to remain at the formation's speed?If the latter, then we have found that, unless the initial formation spacing is over 700 or 800 yards, it is very easy for ships in a single line ahead formation to close to within 500 yards any time a turn in succession is made.

One of the key things every young officer is taught is the fine art of station keeping (maintaining your position in a formation, no matter the movement of the formation). A formation (for example, line ahead) will maintain its following distance (normally 400-500yds, but can be larger, per orders) throughout various turns and such by minor adjustments in speed and helm. So my approach is that the separation is maintained throughout for a set formation. (Of course, if a ship within the formation suffers a major loss of speed, then either drop the speed of the formation as a whole or detach the ship from the formation by moving it out on its own). For a ship in formation to "run up" the stern of the ship ahead would be a sure fire career killer for the officer in question!

[Mark Sieber]

Our group recently started playing GQ3--good rules!--and is having some difficulty with the effect of scale on larger ships' collision risk.We're playing at the original scale, 1cm=100yds, with 1:2400 scale ships.When sailing line abreast, a turn into column causes collisions in ships with long models. It's functionally impossible to stay within allowed formation distance and not risk collision, the over-scale length fills the gap as they swing into line, putting them within 500 yards of one another.We've had an interesting discussion, but have yet to agree on a remedy. Here are some of the options:1. Keep the 500 yd collision risk, but allow formations of larger captial ships to to be further apart.2. Reduce the risk distance to 2 or 2.5 cm. The downside is the reduced risk when divisions under different captains are trying to maneuver in proximity, or when a ship in formation takes, say, an engineering hit: these are the circumstances where I think the current risk is appropriate.3. Adjust the speed of each ship as you make turns. This is the best solution, in that the rules aren't changed and the captains must be aware of the risk of collision, but it significantly slows down play, and focusses a player's attention on being a helmsmen, instead of a tactician.4. Allow ships in a division to declare station keeping, and 'automatically' adjust the separation distance during simple column to line and line to column maneuvers (yes, this does reduce some risk that would occur in the real world) but retain the original risk distance and division separation limit. However, any involuntary change of speed or aspect in a ship in the division triggers the original rule, and separate divisions must still abide by this.5. Declare a single point on a ship as the ship itself, to reduce the functional size. We rejected this as being too small a 'target' for risk of collision.6. Adjust the die roll (as discussed earlier in this post.) This makes for a lot of die rolling and slows the game, plus it gives the impression that sailing involved lots of near-misses which demanded as much focus from the Captain as did tactics and gunnery.7. A mix of #2 and #6. Carries the 'cons' of both.We also found that if we play at half-scale with 1:2400 models, the scale problem applies to even smaller ships.Any thoughts?Thank you,Mark Sieber

[Mark Sieber]

In the previous post, I intended to say die roll mods were discussed earlier in the thread, not the post. Apologies,Mark S.

[Dave Franklin]

We effectively play your option 5, as we measure all ranges fore-funnel to fore-funnel. Remember at GQ's scale of 1cm = 100 yards, the biggest ship would only be about 3cm long.Our biggest quandry on collisions is, do we only look at where ships end their move or when ships get close to each other, do we "impulse move" to see if the ships actually get within 5cm/500 yards of each other? There are advantages and disadvantages to both (e.g. the first is far quicker, but can lead to some weird "gamey" moves where the ships move more like the Blue Angels).One other thing we tend to do is give ships within the same division the benefit of the doubt, as long as they are simply "station keeping".I should also add that while we like to play all of the optional rules that apply to gunnery, we don't (or at least haven't) played optional rule 1.2.8 Altering Course Within Minimum Range. If one were to play that rule, it seems if you can ammend your plot halfway through when an enemy ship/division gets within 2000 yards, you should be able to do the same for a friendly ship/division.

[Jim O'Neil]

I think you have covered all the possibilities ... I would point out that 500 Yards for multi-thousand ton ships that take miles to stop and hundreds of Yards to turn, is pretty close.You might try keeping 1000 yards between ships, it should help some as well. It is also Historical if you read WW 2 history.

[Lonnie Gill]

Mark,There's been some good dialog on this subject. I agree that most of us are more interested in being tacticians, rather than helmsmen. But, moving ship formations in close quarters was not as easy as we make it in a game - as many an OOD found to his cost - and the unexpected did happen. Thus, captains maneuver in close quarters at risk.Two additional thoughts. First, 5oo yards is the minimum distance fore and aft in GQ to enable ships in the same division to have some chance to react to an unexpected maneuver. You may wish to increase your interval beyond the minimum as Bravo6 suggested. I've added a simplifying clarification in FAI [the upcoming WWI rules] that if ships maintain a 500 yard minimum separation, they don't need to test for collision with other ships in their own division. They would still need to test against ships in other divisions.Second, it was quite common to maintain intervals of 1,000 yards or more between divisions and/or columns to minimize the collision risk.LONNIE

[Mark Sieber]

Thanks, Lonnie.I was hesitant to place my original post, as there is a great temptation to make the game 'easier' at the cost of representing the real challenges facing captains. I did so because of the technical problem of spacing within divisions when using dramatically out-of-scale larger ships.On page 1-3, the rule states:Formations The ships of a division move in either LineAhead, Line Abreast or Quarter Line formations, conformingto the movement of the flagship, equally spaced 500 to 1000yards apart in a seaman like manner.However, even when keeping station within a division at the maximum 1000 yards, battleship models in 1:2400 will risk collision when turning 90 degrees from line abreast into column.Models of Italian Littorio class battleships, for example, is 110 yards long on the table--in making a division turn at 1000 yard separation, the models actually touch each other once in line!I'd rather not tinker with the rule, but we were finding collisions unavoidable while doing this basic maneuver and following the letter of the rules.Not testing in the same division will be a cure, but then misses the problems which occur when one ship is hit and slows to create a problem for it's mates.Perhaps I was asking about the wrong rule: May ships in the same division be more than 1000 yards apart? Thanks very much,Mark

[DAVID THORNLEY]

From my observations, it's reasonably correct to say that a line-ahead formation of homogeneous ships (all cruisers, or all destroyers, etc.) will be about 1/3 ship and 2/3 interval. The standard GQ scale is 1cm = 100 yards, which is about 1:9000, so a 1:2400 model would account for ship and interval.Therefore, for 1:2400 ships of the same rough types in line-ahead, I'd allow the ships to all but touch without checking for collisions. 1:6000 are smaller, and so there should be some additional interval, about half a ship length if my mental calculations are correct.This will allow historical concentrations while being easier to use.Of course, I'd enforce the rules strictly for ships of different types, or in different formations, and probably fudge it in the case of a sudden speed loss.

[DAVID THORNLEY]

From my observations, it's reasonably correct to say that a line-ahead formation of homogeneous ships (all cruisers, or all destroyers, etc.) will be about 1/3 ship and 2/3 interval. The standard GQ scale is 1cm = 100 yards, which is about 1:9000, so a 1:2400 model would account for ship and interval.Therefore, for 1:2400 ships of the same rough types in line-ahead, I'd allow the ships to all but touch without checking for collisions. 1:6000 are smaller, and so there should be some additional interval, about half a ship length if my mental calculations are correct.This will allow historical concentrations while being easier to use.Of course, I'd enforce the rules strictly for ships of different types, or in different formations, and probably fudge it in the case of a sudden speed loss.

[Lonnie Gill]

Mark,We all recognize that scale (i.e. reduced) ranges enable a scenario to be resolved in a reasonably sized area, as few of us have access to a gym for our hobby. This works well most of the time, but can be a bit of a compromise vs 1:1 ranges at very close quarters. The spirit of the upcoming rules clarification, that exempts collisions between ships in a division that maintain the minimum 500 yd separation, is to exempt captains from taking unrealistic measures to deal with the scale vs 1:1 range discontinuity. We want to keep the focus of the player on commanding ships rather than concerning themselves with the full intricaties of conning the ship. In the same spirit, we have adopted a standard, average turn radius rather than slightly different ones for different types of ships. In reality, the radius varies from one ship design to another rather than by types and, more importantly, varies with the speed a ship is steaming. All these complex variables have been streamlined into a common, average turn radius to keep play moving and focused on the many other decisions a captain or admiral had to make in action. His crew steers the ship and actually aims the guns and torpedoes. Another view of the whole formation maneuver process is provided by the written, standard USN tactical doctrine from 1944. Old battleships (pre "fast battleships" of the North Carolina and later classes) were to maintain an interval of 700 yds between ships and 2100 yds between divisions. For fast battleships (BB55 and later) these were increased to 1000 yds between ships and 3000 yds between divisions. Distances for Cruisers were similar at 600yds between ships and 2600 yds between divisions. In historical actions, ships often varied from these standards, but closer intervals resulted in near collisions and more than one actual collision under fire or when the ship ahead suddenly altered course or lost speed as a result of damage. You may want to use these standards, which were developed in the 1939 - 1941 Fleet Problems, as normal guidance for your scenarios. The GQ III maneuver minimums are intended to be just that, the bare minumim to avoid collisions between large, fast moving vessels.LONNIE