|09-30-2016, 02:44 PM||#1|
One insane earth to pluto trajectory & another completely sane one
Two days ago, I downloaded the UCGO addon to fly the Arrow Freighter again after a really long while. I didn't remember too much about it from the last time I used it, so exploring the Arrow Freighter was almost like exploring a completely new ship.
The first thing I did after loading the Arrow Freighter ship was to check it's default fuel values, which was 92.421 km/s!!!! Considering that most of my trips to outer planets/Kuiper belt objects only require fuel to get to venus, which would be somewhere around 3.9k to 4.3k, this was an insane amount. Even performing a braking burn to land on a dwarf planet would add at most 23k, the addition of the two still being less than one third of the total fuel available on the Arrow Freighter.
So I decided to find out how fast I could get to pluto from earth using the fuel available on the Arrow Freighter. But not just a direct flight, I also wanted to see how useful a sling around jupiter would be, at such insane speeds. So I came up with a earth-jupiter-pluto trajectory that used 91.38k of fuel, leaving some fuel because I had no idea if the MCC's would also take an insane amount.
So, my first doubt was, do the available tools,TransX/IMFD work for such huge burns? Will I be on the correct trajectory after I finish my burn or will I be way off? To answer that, as far as TransX goes, by looking at some abnormal values presented by TransX on which I wouldn't go in too much detail here, no I don't think it'll work, I didn't try. The IMFD target intercept + orbit eject program? It's begin burn time was off by a couple 100 seconds from the actual correct begin burn time, which I found using the IMFD map program, so no, I don't think even the IMFD orbit eject program could be used for such long burns. I input the values from the IMFD target intercept program into the deltaV program & adjusted the time until I was getting close to jupiter in the map program of IMFD and it worked fine.
Speaking of MCCs, any burn in the Prograde/Retrograde direction had little effect on our trajectory since there was already this huge velocity vector in that direction, but Plane change/Outward worked like normal & MCCs didn't require stellar values.
The trip from Earth to Pluto as per TransX took 443.87 days, with a jupiter sling. Jupiter increases our speed as well as changes our plane to get to pluto. To see how useful jupiter was, I planned a trajectory straight to pluto without jupiter by adding plane change fuel & then subtracting the prograde fuel to get the same fuel amount as before & that made the TOF to be about 447.33 days. Not too much of difference here, but if we were to add prograde to the direct earth - pluto trajectory so that the TOF becomes 443.87 days, we would have to add some 880 dv more. So jupiter saves us fuel by that amount.
But these values are obtained from theoretical two body calculations, when I executed the EJP trajectory, it took 454 days to get to pluto, largely affected by how we perform our MCCs. While arriving at pluto, I was travelling at a whooping 119.3 km/s speed relative to it.
THE SANE TRIP TO PLUTO
In this scenario, the delta glider(Not the Arrow Freighter) goes from Earth-Venus-Earth-Earth-Jupiter-Pluto. But, this one has a deep space maneuver of 170 dv to perform after the first earth sling, which makes this my first slingshot plan which involves a DSM.
Why does it require a DSM? Because the Pe/Pl rad at my first earth sling was below 1(but close to it), which means I needed a larger boost than what the planet could offer from above the surface. To counter that, I had two options.
A) Change the inclination angle until the Pe/Pl rad went above 1, which would mean I no longer sling earth without any inclination change, which would also mean I need to perform a plane change correction at a node to intercept earth a second time to get to jupiter.
B) Change the outward angle until the Pe/Pl rad went above 1, which would mean I no longer would be able to intercept earth at the right position because I would be arriving back too quickly. To get around this problem, after my first earth sling, I waited until I reached the periapsis of my orbit around the sun & then performed a prograde burn to intercept earth at the right position.
Option A required 260 dv of burn, but option B required 170, so I went with option B.
Even though the DG is a futuristic ship, the trajectory it follows in this scenario does not require a futuristic ship, neither does this trajectory require a large realistic rocket.
Time it took to get to pluto after flying the trajectory - 15.64 years. Total fuel used (Excluding MCCs) - 4.3852k. Arrival velocity at pluto - 18.36 km/s
Scenarios attached below. You'll need the UCGO addon to view my Earth-Jupiter-Pluto scenarios.
Last edited by downloaderfan; 09-30-2016 at 02:57 PM.
|Quick Links||Need Help?|