So a ship has 2 speeds.    Normal speed or super speed (when not next to planets / ships)

The book talks about air envelopes spanning a ways out past diameter of the planet. The boo talks about 5,000 diameter planet with 5,000 diameter . With the speed of ships it seems like going from planet to wildspace will take a LONG LONG time.  

is this intended.  Seems like when they wrote the system (as short as it is) they didn't account for this part at all. People going to/from planets would be somewhat common, but it seems very clunky based on the rules in the book.

On one hand, it only says they drop to their slow speed when they “come close to” something big enough to have it’s own air envelope and that the distance should be at whatever the DM thinks is convenient. So for planets, you don’t necessarily drop to slow speed when hitting the air envelope (remember real world physics don’t apply, so you could potentially cruise through the atmosphere of a planet without getting close to it at millions of mph without burning up). You only drop to slow speeds when narratively convenient. 

That being said, it is a big oversight and confusion in the rules. In the original 2e rules, it specifically listed the times to leave a planet’s gravity well and enter Wildspace as ranging from 1 minute to 16 hours depending on the planet size. Since pretty much all of the other 5e rules are nearly identical to the 2e rules, I’d say that works as a decent range.

Edit: I’m failing to find where the size classes are defined in the old books in a quick search, but the Spelljammer Fan Site has these numbers which match all the examples I saw offhand in the books, so are likely correct.

Celestial Body Sizes

I feel like I'm going to have to buy a lot of spelljammer stuff on dmguild to get more rules in spelljammer, and while I like using dmsguild I usually don't feel its as much of a requirement as it will be with spelljammer.

Also thank you for that information. It was very helpful reference!

I can double check some of the ship combat rules, maybe, but I don't think there was a lot more to the old rules either. It was pretty sparse, but I'll see about re-reading some of them to see at least what else was in there.

The majority of the original Spelljammer products were primarily detailing different locations to visit - although that does make them still really useful to 5e games! But as lore rather than additional mechanics.

However, I do imagine a lot of writers will be publishing rules expansions on DMs Guild for those who want crunchier space rules. It's definitely an open design space to explore.

Check out War Captain's Companion on DMsGuild. It was published by TSR and summarized the other books rules as well as introduced a simplified movement/combat option I still use.

This honestly feels cobbled together and low effort. Even the Spelljamming ship maps are simply recycled from the original 2e release: https://waynesbooks.files.wordpress.com/2020/11/dscn8804.jpg?w=600

It feels like they just took the old ruleset, through out anything that didn't translate or seemed too complicated, and didn't replace any of the cut material.

As for this air envelope oversight, I think I'm going to use a homebrew rule that any object over, say, 500 miles in any dimension has an air envelope that extends 1/100 of its diameter. So an Earth-sized planet of about 8000 miles would have an atmosphere of around 80 miles, which isn't too far off Earth's, which is about 60 miles. So the slowest Spelljamming ship takes 1.11 days to leave the envolope (assuming 24 hours of consistant flight, which might not be possible), while the fastest takes about 10 hours. It ain't perfect, and I might fiddle with to to be 1/500 or maybe 1/1000, I'll see how it goes in my games.

The problem is the simplistic definition of an air envelope. The rule works fine for ships or small asteroids but doesn't make sense scaled up for planets. There should be a maximum air envelope size.

In the real world, Earth's atmosphere is breathable up to only a few miles. For example, climbing to the top of Mount Everest is possible without using oxygen tanks, but is very difficult. In game terms that would result in some levels of exhaustion. Everest is 29,000 feet tall or about 5.5 miles. So, getting back to 5e fantasy worlds, a reasonable max size for an air envelope would be 4 or 5 miles above the planet.

That would make the typical escape flight time about one hour.

Thank you for the discussion here.  How is anyone handling the fact that Ghosts of Saltmarsh has better ship board, combat rules than Spelljammer does?  For instance, I am looking for references on...how does a Spelljammer ship not have Ship Actions like ships in Ghosts of Saltmarsh do?  Clarity on , a Spelljammer with a Magonel that takes 2 actions to load, 2 actions to aim, 1 action to fire....whose actions are those on a Spelljammer ship?

None of the ships have actions listed?  Stats even?  How is anyone else thinking on this to handle?

Quote from Sharkman2361 >>

Thank you for the discussion here.  How is anyone handling the fact that Ghosts of Saltmarsh has better ship board, combat rules than Spelljammer does?  For instance, I am looking for references on...how does a Spelljammer ship not have Ship Actions like ships in Ghosts of Saltmarsh do?  Clarity on , a Spelljammer with a Magonel that takes 2 actions to load, 2 actions to aim, 1 action to fire....whose actions are those on a Spelljammer ship?

None of the ships have actions listed?  Stats even?  How is anyone else thinking on this to handle?

Part of the difference is that Spelljammer ships operate differently than other ships due to the Spelljammer Helm. So it only takes 1 person to make the ship move rather than a bunch of crew working together. As for the weapons, the actions are the crew's actions. So the mangonel that takes 5 actions to fire also requires 5 crew to operate it. And since the book says to use the Side-Initiative from the DMG, individual crew initiatives don't matter. Just 5 crew members are busy firing that mangonel on their turn (or if fewer, I imagine it just takes more than 1 turn to fire). In Ghosts of Saltmarch, the ships have actions because it is abstracted from a lot of crew members doing things together. With Spelljammer, it doesn't necessarily need that level of abstraction. Just that person is in the helm flying the ship, those 3 people are operating that ballista, etc. The Descent into Avernus infernal war machines work the same way.

Thank you that is very helpful.  So a tad more clarity, when the Mangonel says, crew of 5, 2 actions to load, 2 actions to aim, 1 action to fire...that mangonel can fire every round if there is enough crew assigned to it?

Quote from Sharkman2361 >>

Thank you that is very helpful.  So a tad more clarity, when the Mangonel says, crew of 5, 2 actions to load, 2 actions to aim, 1 action to fire...that mangonel can fire every round if there is enough crew assigned to it?

That's at least how I read it. I believe each also says "Mangonel (Crew: 5)" or whatever and spot checking, the listed number of crew to operate seems to always match the number of actions needed to fire. So I at least interpret it that way, but someone correct me if I'm wrong.

I couldn't find anything specific, but as a DM, I would also be open to allowing fewer crew members to operate it if necessary but it just takes more than a round. So, for example, if there's only 1 person, they can fire  that mangonel once every 5 rounds. I couldn't see that specifically stated, and some things like the Bombard's cannon that takes 4 to load might just be too big for 1 person to do alone, but I could see an interesting situation of only a few people scrambling to operate more weapons than they have crew for. :)

Could also see DMs ruling things like a fighter's action surge allowing them to do 2 of the actions, etc.

There are already some good add-ons stuff posted in both DMS GUild and /spelljammer on reddit for enhancements to ship combat.

I get Wizards wanted to keep it simple, but the base level still could have had a little more meat added to it.  Spelljammer ship combat is one of the draws of spelljamer. Shame its so bland by default.

They missed an obvious opportunity to make Spelljammer helms optional and evolve the airship concept giving characters and crew something to do other than consume air and clean artillery.

Quote from Sharkman2361 >>

Thank you that is very helpful.  So a tad more clarity, when the Mangonel says, crew of 5, 2 actions to load, 2 actions to aim, 1 action to fire...that mangonel can fire every round if there is enough crew assigned to it?

 

Yes.  And apparently the attack bonus and damage values are independent of the crew's statline, so it's not generally worth shelling out more money for more competent crew (outside of other ship concerns, like dealing with jammer leeches or casting mending).  But since Spelljammer explicitly has firearms, I imagine absolutely everyone is going to replace their ship's mangonels with cannons.

In the spelljamming helm item description it says you move at the ships speed while you are 1 mile or closer to any object that weighs 1 ton or more.  So you have to travel 1 mile away from the surface of the planet then you can begin moving at the 100 million miles per 24 hours speed.

Quote from PirateJit >>

In the spelljamming helm item description it says you move at the ships speed while you are 1 mile or closer to any object that weighs 1 ton or more.  So you have to travel 1 mile away from the surface of the planet then you can begin moving at the 100 million miles per 24 hours speed.

 "If the ship is in space and no other objects weighing 1 ton or more are within 1 mile of it, you can use the spelljamming helm to move the vessel fast enough to travel 100 million miles in 24 hours." 

Note the "If the ship is in space" part. It seems, to me at least, that you have to be in space, i.e. outside of a planet's atmosphere, to travel at high speeds. Meaning you have to travel the diameter of a planet at low speed anytime you want to reach or take off from a surface, as atmospheric height from a body's surface is equal to its diameter.

I mean, that sounds like good traffic safety -- areas close to planets are more likely to have other ships in orbit. Crashing into them at full speed sounds no fun.

Well, 5000 miles at 3mph is 69 days. 

Our you just use Earth as an example of a "real" planet. Our atmosphere is between 5.6miles at the poles to 11miles at the equator with an avg of 6.8miles. So I would say 2 hours is a fair time.