Getting to Venus in the DGIV

[Clavius0712]

Hi all,

Today I thought I'd try something I'd not tried before. Take off from KSC and fly to Venus, orbit Venus a few times, then fly back to Earth.

At first this seems fairly straight forward. I checked the Cosmic Train Schedule site and it gave me a launch window of 2nd Aug 2010, so I booted up Orbiter and loaded the "Landed KSC Depart for ISS" scenario in the DGIV "Earth Scenery" folder and set the date accordingly.

Through trial and error I found that running the Ascent autopilot with a heading of 100 degrees (PRO903SPEC100) got me nicely lined up with the orbital plane of Venus. I only needed a thirty second burn in orbit to reduce the relative inclination to 0.01 degrees. So far so good.

I then did the burn to start off for Venus and waited..and waited. Eventually my O2 ran out and I'd barely left Earth's orbit around the Sun.

Checking the Cosmic Train Schedule site again I found it would take about 5 months to get to Venus using a Tangential Transfer. Even if I got there OK, the next window for a transfer from Venus back to Earth wasn't until 6th April 2012!

Now I've read somewhere that NASA was seriously thinking of putting a man in orbit around Venus and returning him back to the Earth at around the same time as the Apollo flights. If so, they surely couldn't have been planning on using Tangential Transfers, as the trip times are way too long.

Does anyone know how they planned to do it? If not, can anyone recommend the best way to do it in Orbiter that is a happy medium between fuel efficiency and length of trip?

 

[ar81]

I think Flytandem has great tutorials on it.
Flytandem is the master of slingshots and fuel efficiency.

 

[RisingFury]

Fuel efficiency means longer travel times.


Go into DGIV settings and set the fuel and oxygen reserve to largest value - a trip to Jupiter. Though if you're serious about long travel times with DGIV, just turn off the function of crew dying, or you could use the default DG.

 

[Clavius0712]

Thanks for your replies.

I did a search in Google for the NASA plans from the Apollo era and found they had anticipated a fairly long trip time - about 4 months to get there for a very fast flyby of the planet according to this Wikipedia article - so maybe I was being too optimistic for a shorter flight!

I will do as RisingFury suggests and try again with more O2 and fuel.

 

[Ark]

You could do the Energia/Delta Tug launch and use the tug to set up a faster trip. I haven't really played around with faster transit times, though, I do everything minimum-energy.

 

[ijuin]

You can also extend your life support time by carrying fewer crew--the default time is for a crew of five, so if you were carrying only three, it would last 5/3 as long, or 5/2 as long with a crew of two.