Request DG-EX launcher

[Grover]

is there currently a launcher for the DG-EX? i only ask because it is shaping up as quite a nice craft, but its realistic settings make it difficult, and inefficient to reach orbit, even when using the plasma engines as well as the conventional rockets to get above the thickest of the atmosphere.

ive tried using the process described in the documentation, but it remains extremely difficult, and tempermental, i usually have to use full trim and gimbal to keep the nose up and the acceleration gets down to <1m/s^2.

a launcher would make it much easier, even if it does have to be a manual launch (or possibly use the atlantis launch LUA script?)

 

[Izack]

Ta-da!

[ame="http://www.orbithangar.com/searchid.php?ID=3417"]DGEx on JupiterIII-X[/ame]

Alternatively, you can use Velcro Rockets to make your own launcher, if this one is overkill. Strapping the SRBs directly to it might be interesting.

EDIT: Holy crap, this was my 2000th post.

 

[Grover]

ill give it a go once ive got this blasted essay done, thanks!

looks a little big, you sure it wont blast me into the sun or somethin?

 

[N_Molson]

A little big for the DG-Launchers :lol:

Maybe a super-launcher for this craft/the XR-5 could be fun

 

[Grover]

i was thinking something similar to the ones that launch the DG-IV, but i guess this will do, ill just make sure to cut the engines nice and early. would something this size have a "shut down" button? or i could just jettison it and go to my own thrust once im out of the atmosphere and on my way up (at perapis, apoapsis well above altitude)

one worry is that it says that says (on the jupiter launcher download) that its target altitude is about 500KM, which is a little high to go to the ISS. fine for the moon (awesome in fact) but its a little high.

and in keeping with the realism of (make sure your launcher ends up back on earth, an eccentric orbit like the ET SEP on the space shuttle could take care of that

 

[PhantomCruiser]

I found it easier to use the conventional launch profile when I had a joystick. The up/down trim helped a lot, but I never got to where I could walk away from the computer for more than a few minutes. With the DG-EX, you've pretty much got to fly the craft to orbit, rather than raise the nose and firewall the throttle like a DG.

And it's not that it's inefficient, just not possible with current tech. This is what I think would probably be the ultimate goal of an actual SSTO winged craft. A nice and steady climb to orbit with a relative low 'G' load.

In the DG-EX thread there are a few more suggestions for launch profiles also, there is always more than one way to skin a cat...

 

[Sky Captain]

Maybe a shuttle stack could be used. Remove the shuttle from the SRB and ET stack and put a DG EX there. I think it should be possible with Velcro rockets

---------- Post added at 11:07 PM ---------- Previous post was at 11:04 PM ----------

Ops, forgot that DGEX has low thrust so in place of shuttle stack try to use Energia which have the main engines on the core.

 

[Grover]

@PhantomCruiser
well, it may well be possible, and i am sure that people here can and have done it. my point is that its a little difficult. sure SSTO is better for the environment and all that, since making a huge ET and some SRBs cant be very eco-friendly, but my first thought was to make it launch vertically like teh shuttle.

an alternative (a midway point if you will) is a scramjet ascent. that would five a high tangentenial velocity, could leave you in the higher reaches of the atmosphere where a little burn could change your course to an orbit, and from there that huge drag factor isnt there, so it is easier to get into LEO. like an XR-2 launch and SCRAM ascent in slow motion.

 

[JonnyBGoode]

You could put it on top of a TX...

 

[Grover]

or maybe just fit it into a cannon? :rofl:

seriously though, thats worth a try

 

[JonnyBGoode]

You could put it on the Delta Cannon, but I don't think that would give you any real advantage...

 

[PhantomCruiser]

Actually I'd thought of the TX, but I got called away for dinner before I could amend my earlier post. How she do in that configuration JonnyBGoode?

 

[Hielor]

ive tried using the process described in the documentation, but it remains extremely difficult, and tempermental, i usually have to use full trim and gimbal to keep the nose up and the acceleration gets down to <1m/s^2.

If you're having to use full trim, I suspect you're not using the correct process.

The DG-EX has a quirk where the engines become less effective at 30km altitude, and then even less effective again at 60km altitude. This should probably be dependent on pressure instead of altitude, but it'll do the same thing on Mars or Venus as on Earth, at the same altitudes.

What you want to do is get up to ~29k as quickly as you can, and then level off there until full nose down trim can no longer keep you below 30k. Once crossing 30k, climb up to ~59k as quickly as you can without actually losing speed, and then do the same thing--level off there until you need full nose-down trim to stay below 60k, then let yourself drift above it until you reach orbital velocity.

 

[JonnyBGoode]

Actually I'd thought of the TX, but I got called away for dinner before I could amend my earlier post. How she do in that configuration JonnyBGoode?

Does very well... but you need a really long runway.

 

[Grover]

edwards AFB it is then

 

[River Crab]

One more possible combination would be using a mass driver to "shoot" it up to a high altitude, making the ascent faster (and saving some Dv), but we don't really have a good one for Orbiter aside from Kulch's old Lunar Mass Driver.

Edit: it would also need to be ridiculously long to keep the Gs safe for human use, and not negate the advantage of what would be a slow, gentle ascent...

I really wish it had a config file like the XRs, though. I like flying to orbit, but this takes REALLY long without risking use of time accel in atmosphere.

Also: for those who want to make the ascent a bit more exciting: Use a chase plane (or an escort)!
Being a spacecraft, I'd guess that it has no ECM, so for sensitive payloads, who you gonna call?

You can use the docking HUD to intercept it and fly in very close formation, making the first part of the ascent that much more exciting. I managed to follow it in an F-22A to within a distance of 200m up to 17km alt, before my engines flamed out. AerobrakeMFD's autopilot can be a help here.

Also, with clever use of replays, you can have the DGEX take off by itself, and switch to it after you've landed the chase plane. Which lets you focus on flying in extremely close formation (less than 20m) at supersonic speeds...

 

[Schimz]

If you're having to use full trim, I suspect you're not using the correct process.

If trim is set at full, your climbing rate will never be stable. You must gimbal the engine and fine tune the trim to get a steady climbing (I can make laundry folding or cooking during ascent).

The DG-EX has a quirk where the engines become less effective at 30km altitude, and then even less effective again at 60km altitude. This should probably be dependent on pressure instead of altitude, but it'll do the same thing on Mars or Venus as on Earth, at the same altitudes.

That's the 3 modes. Below 30km/M3.5: turbojets ; 30km to 65km/M23 : scramjet ; In vaccum : retractable rocket nozzles.
And yes, it's rely on altitude. The engines perf are like I've wanted, but the algorythm is ugly and only relevant with Earth atmosphere.
Due to the fact that systems are not modeled (i.e. : overhead panel), the engines switches are automatic (i.e : not manual) and abrupt (sorry, I'm the first to whinning about that :facepalm.

About efficiency :

• Does anyone try payloading 180 tons of stuff to LEO ? :shifty:
• A "world record" : 29min (sim time) to LEO

 

[PhantomCruiser]

Dang 29 minutes, sweet... I usually average 35 minutes.
I "accidently" launched the other day with the stereo turned up pretty loud. My wife came in right as I firewalled it for the takeoff roll. Epic sound! The room shook, the windows shook, then the wife walked in the room (busted). But I think it was worth the evil glare I'd gotten.

 

[Schimz]

Dang 29 minutes, sweet... I usually average 35 minutes.

PRPLEVEL 0:0.25 1:0.2

And no payload of course