Problem DG to ISS, degrees of pitch for climb and launch heading?

[rocketdued]

i found few problems in the manual for the deltaglider to iss scanerio. it states to riase the nose to 70 degrees nose up pitch. and turn to heading 140. but in tex's tutorial it says to pitch up to 50 degrees nose up pitch. and turn to the east which is 090. which is correct?

 

[Fabri91]

It depends. 140 degrees is more or less the heading you have to fly when the ascending part of the ISS's orbit crosses KSC, 90 degrees would bring you more or less in plane with the Moon, starting again from KSC and, of course, only IF you start just as the orbital plane is passing over you.

There isn't a heading that brings you always to the ISS everywhere when starting at a randomly chosen moment.

 

[rocketdued]

dg to iss

ah ok. i'll remember that. so the 140 heading is correct. but the pitch angles are differrent.

 

[Fabri91]

That doesn't make much of a difference, at least with the dg, just make sure to get above 20-30km before relatively quickly to get out of the denser parts of the atmosphere...

 

[orbekler]

The standard deltaglider tutorial will tell you to nose up at 70° then when you reach 30km to begin to get nose down to few degrees, and you can do that, but when you use vessels like XR series, you need to climp up slowly (50° first, then gradually keeping about 100m/s of climb rate) in order to operate efficiently scram jets. With experience you'll notice that.
As for the heading, is 137° for ISS (few degrees make the difference in fuel expense).

 

[rocketdued]

dg to iss

oh ok. well i'll give the 50 degrees a try and see what happens. i havn't been playing orbiter for quite a while. so i will try tex's information and see what i can get. :tiphat:

---------- Post added at 05:49 PM ---------- Previous post was at 05:45 PM ----------

oh ok. yeah the manual i think says to pitch up to 70 degrees and then at 30 km's pitch down to 20. i'll try the one from tex first maybe i can get lucky one of these days and actuly make it:lol:

 

[Tex]

If you watch the first part of my "XR2 Wideawake to Brighton Beach" tutorial, I explain better than my older "DG4 to ISS" tutorial how to determine your launch heading and when to launch. Although my new tutorial is for going to the Moon, the principle is the same when you're looking at your targets orbit on the MapMFD to get a visual reference of the approaching intersection. For ISS it will either be a NE or SE launch heading, depending on which node is approaching and crossing your launch site at that particular moment.

 

[rocketdued]

dg to iss

oh ok. well i also think im taking off to early. but still the manual is confuseing. cause you say to use 50 degrees. untill 30 km's. but the help file for the mission says 70. :facepalm:

 

[Tex]

Anywhere between 50-70 degrees is perfectly acceptable. Once I pass 10km altitude, I begin pitching down to around 25 degrees which maintains a slower rate of climb allowing you to build up the horizontal velocity required to reach orbit. By the time my altitude is around 65-75km, I'm basically flying level, strictly building up that horizontal velocity. Once orbital velocity is reached and my ApA is around 350 km, I shut down my engines and coast up to my ApA (high part of the orbit) and do a prograde burn to circularize the orbit.

 

[rocketdued]

dg to iss

ah ok. thank you i will try that.

 

[Carmen A]

oh ok. well i'll give the 50 degrees a try and see what happens. i havn't been playing orbiter for quite a while. so i will try tex's information and see what i can get. :tiphat:

---------- Post added at 05:49 PM ---------- Previous post was at 05:45 PM ----------

oh ok. yeah the manual i think says to pitch up to 70 degrees and then at 30 km's pitch down to 20. i'll try the one from tex first maybe i can get lucky one of these days and actuly make it:lol:

Don't worry about 'making it' - you have unlimited resources and time with no political pressure unlike the real world.

You can freely experiment to see what sort of climb angle is optimal for your mission profile.

It is not necessary to base mission success for your early orbital attempts at reaching the ISS. After all in the real world they progressed quite steadily from the age of ballistic missiles (suborbital) to LEO and beyond. If you can focus on launching to orbital velocity efficiently and holding a very stable orbit at a set altitude, then it's quite a simple matter to reach the ISS (you are aiming to mirror its orbit anyway).

 

[rocketdued]

dg to iss

yes thats true. but i havn't played the game in about a month. so im probebly rusty again:lol:

 

[Rtyh-12]

Isn't this like the third time you are asking this...

You don't actually have to follow strict guidelines. Just fly with your nose higher until you get high enough, and then lower your nose. After that just continue to burn forward until your ApA (apoapsis altitude) reaches 350 km.

The numbers Tex suggested(50-70 degrees, pitch down at 30 kilometers) are (of course) just fine.

Also experimenting is excellent.

 

[rocketdued]

no sir. just stateing that i thought there was a glitch in the manual thats all. i got conflicting information.

 

[Rtyh-12]

No, the numbers in the manuals will work too, but other numbers can be better (save more fuel).

 

[rocketdued]

oh ok. just makeing sure.

 

[Kveldulf]

Its worth mentioning that the two scenarios you're looking take place at different times, and as such, the ISS will be at different positions, requiring a different launch heading. The pitch degree will vary from person to person. I tend to pitch up to around 50 degrees, and then start to level out around 15km, reaching around 5 or 10 degrees by 25km.

 

[rocketdued]

oh ok. i think thast will work. but im still taking off to early.:lol: im way ahead of the space station when i do get into Orbit. :lol: thats not good. i can't dock with the space station on my tail. it has to be on my nose:lol:

 

[Wishbone]

Searching here for posts made by Tommy with the keyword "pitch" would give you a lot of very useful information on that.

 

[PhantomCruiser]

I usually wait until the station is off the coast of Africa before launch, That way I'm lower and faster than the ISS (or whichever station). Unless the scenario dictates to launch earlier...
Also, are you flying the stock DG, or the DGIV?