I was spreadsheeting some travel numbers for fun, expanding on a recent post in the misjump thread.
What was enlightening when it comes to intersystem travel, is how little the drive rating impacts overall travel times when you're limiting your burns because of fuel.
When you have a generic Traveller M-Drive, with "infinite" fuel, then drive rating has a great impact, because you can burn, baby, burn all the way to halfway before you decelerate.
Consider simple Jupiter to Earth scenario. Jupiter (in this case) is 588Mkm from Earth.
With a 1G drive, full burn/decel, it's about 5.6 days of travel. 2G, it's 3.8 days, almost 2 days difference. 5G, 2.4 days. Over 3 days faster.
A generic M1,J1 TNE Free Trader has 28 G-Hours of fuel. 1G for 28 hours.
If they burn 1G for 10 hours to start, needing 10 more to decel (handwaving gravity parts away), the trip takes 19.3 days.
If the ship had, say, a 5G drive, it could burn that much fuel in 2hrs, instead of 10 hrs.
In the case, the trip would take 18.98 days.
"Big deal"
The size of the drive is proportional to the G rating, so a 5G drive is 5x the volume/mass of a 1G drive.
Now, all that said, flying from Earth to 100D, a 2G drive saves about an hour over the trip (2hrs if you count the trip coming back in once out of jump). A 3G drive save about 2hr each leg.
You're still stuck in a week of jump, so it's not really clear how important save those few hours in normal space really matter (considering hours are likely consumed just getting in the pattern, docking, etc. which a drive can really help with).
In the end, I can see a lot of commercial ships having, at best, a 2G drive routinely.
Only combat vessels would likely have higher G drives, and that solely for combat maneuver, not even cruising. Why stress the ship and crew with a 5G burn if it doesn't really matter.
So, just a curious bit of insight how little the G rating would impact travel in a HEPlaR galaxy vs an M-Drive one.
What was enlightening when it comes to intersystem travel, is how little the drive rating impacts overall travel times when you're limiting your burns because of fuel.
When you have a generic Traveller M-Drive, with "infinite" fuel, then drive rating has a great impact, because you can burn, baby, burn all the way to halfway before you decelerate.
Consider simple Jupiter to Earth scenario. Jupiter (in this case) is 588Mkm from Earth.
With a 1G drive, full burn/decel, it's about 5.6 days of travel. 2G, it's 3.8 days, almost 2 days difference. 5G, 2.4 days. Over 3 days faster.
A generic M1,J1 TNE Free Trader has 28 G-Hours of fuel. 1G for 28 hours.
If they burn 1G for 10 hours to start, needing 10 more to decel (handwaving gravity parts away), the trip takes 19.3 days.
If the ship had, say, a 5G drive, it could burn that much fuel in 2hrs, instead of 10 hrs.
In the case, the trip would take 18.98 days.
"Big deal"
The size of the drive is proportional to the G rating, so a 5G drive is 5x the volume/mass of a 1G drive.
Now, all that said, flying from Earth to 100D, a 2G drive saves about an hour over the trip (2hrs if you count the trip coming back in once out of jump). A 3G drive save about 2hr each leg.
You're still stuck in a week of jump, so it's not really clear how important save those few hours in normal space really matter (considering hours are likely consumed just getting in the pattern, docking, etc. which a drive can really help with).
In the end, I can see a lot of commercial ships having, at best, a 2G drive routinely.
Only combat vessels would likely have higher G drives, and that solely for combat maneuver, not even cruising. Why stress the ship and crew with a 5G burn if it doesn't really matter.
So, just a curious bit of insight how little the G rating would impact travel in a HEPlaR galaxy vs an M-Drive one.