OHM Launch MFD - v. 1.6.6 for Orbiter 2016

Nope. In this case the difference is about 0.02 degrees so just launch eastwards and do plane change burn.

this is why the ISS launch window for shuttle is five minutes and for Hubble was three hours.
 
Enjo, I am still having issues getting the HUD to draw.

I have the HUD Drawing plugin enabled, I can press the HUD button in LaunchMFD and hear the audio cues, I open the MFD for the HUD drawing and verify that Launch MFD is enabled, I toggle it back and forth just to be safe.

I am running in 2010P1 and the R10 of D3D9 client if that makes any difference, but I tried it using the in-line and same result.
 
Ah... that makes sense. The satellite never crosses the launch site, so there is no intersection.

Understandable. Still, I would prefer a "Best time to launch" countdown if nothing else. Otherwise, it seems as though I need to load the scenario, fast forward until the RInc is at the lowest point, pause the simulation, write down the time, exit Orbiter, reload the scenario, then fast forward back to the time I'd written down -300 seconds. A bit tedious.

At any rate, thanks again for the replies.

So basicaly,I just have to wait for the perfect launch window,where both latitudes match correctly?

Nope. In this case the difference is about 0.02 degrees so just launch eastwards and do plane change burn.

this is why the ISS launch window for shuttle is five minutes and for Hubble was three hours.

I've figured out a nice trick against this problem:

  1. Open Orbit MFD and set it to equatorial frame to read the target's LAN
  2. In Launch MFD enter manual inclination and LAN, where inclination is greater than your latitude by at least 0.3*, but not more than by 0.6*, and LAN is that of the target
  3. Launch to the newly set target
This will get you into orbit in the right time, and will minimize the Rinc.

[EDIT] When I think about it, I could even automate it...


Enjo, I am still having issues getting the HUD to draw.

I'm sorry to hear that... You have email. This may require some more debugging.

I assume that the HUD drawing is working fine for the rest of you?
 
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I assume that the HUD drawing is working fine for the rest of you?

Just done a very quick check in 2010-P1/D3D9 R10 with the stock DG-S ready for launch scenario. At first I had no HUD but quit back to the launchpad and discovered I hadn't enabled the HUD Draw module, re-launched current scenario and it was fine. Toggling LaunchMFD in the HUD MFD switched on and off as expected. Seems fine here :shrug::thumbup:.
 
I've figured out a nice trick against this problem:

  1. Open Orbit MFD and set it to equatorial frame to read the target's LAN
  2. In Launch MFD enter manual inclination and LAN, where inclination is greater than your latitude by at least 0.3*, but not more than by 0.6*, and LAN is that of the target
  3. Launch to the newly set target
This will get you into orbit in the right time, and will minimize the Rinc.

[EDIT] When I think about it, I could even automate it...

Done. Check the attachement. It can be tested for example with a launch from Cape to Moon's orbit.
Notice that since the inclination is very similar to your latitude, it only makes sense to launch to the second launch window, in this case the southern one, because launching to the northern one would increase your latitude to a value above the targeted inclination, which confuses the MFD.
 

Attachments

Done. Check the attachement. It can be tested for example with a launch from Cape to Moon's orbit.
Notice that since the inclination is very similar to your latitude, it only makes sense to launch to the second launch window, in this case the southern one, because launching to the northern one would increase your latitude to a value above the targeted inclination, which confuses the MFD.

Works good Enjo,thanks for the fix.
 
Hi Enjo.

In the last few versions I've been having difficulty with low inclination launches from Cape Canaveral when I try to select one azimuth over the other. This became apparent once again when I tried to target the moon in the latest forum release. Seems like autopilot gets confused near burnout and starts a sharp yaw way out of plane. I think it starts chasing the wrong azimuth, or something, as the two are quite close. I would describe the behavior as similar to what was happening when polar orbits were attempted, before you fixed that issue back in February.
 
Hi

I think I know what you mean. Try selecting the 2nd azimuth available for low inclination launches. For Cape this would be the southern one.
Hope it helps.
 
New version is out. Please note that now, for 2010 version, you have to install [ame="http://www.orbithangar.com/searchid.php?ID=6023"]HUDDrawer SDK v.0.3[/ame] to make it run. 2006 version has it preinstalled as I don't expect anobody making addons for this version.

v. 1.6.1 25-05-2013
- Direct Ascent: added target distance under [Shift A] in DA mode, once AP is enabled
- When setting target with incl. lower than your latitude, a dummy probe will be targeted and can be intercepted
- Selecting 2nd azimuth only for low inclination launches
- Displaying relative inclination also in standard mode
- Bugfix: restoring target from scenario file

New entries in the documentation:

Target input
Whenever you enter a combination of inclination with LAN, as in this case, be aware that due to non-spherical gravity sources (Orbiter's option), the targeted dummy vessel's LAN will drift, so be sure to target the same orbital parameters again a few hours before the launch to update the dummy's position.

You can't launch a spacecraft into an inclination lower than your latitude (in equatorial frame), for example to Moon or Mir from Cape Canaveral. If you intend to intercept these targets anyway, you need to launch into inclination same as your latitude, by launching in a purely eastern direction. After reaching the orbit, you need to perform a plane change manouevre. It will cost less fuel when you launch in the correct time. Launch MFD supports such launches, by using a dummy, which has the same LAN as the target, whose name needs to be entered as usual. Note however, that such launches are limited only to the second possible heading, in case of Cape – southern, because launching into the northern one would increase your latitude to values exceeding the dummy's inclination, which confuses the MFD. In case of selecting a celestial body as your target, you will also have to target it again a few hours before launch, because the dummy may be subject to LAN drift. If you want to launch a winged spacecraft, like DG, instead of launching east, using a dummy, it will surely be more efficient to launch southwards and cruise in atmosphere for as long as your latitude is greater than target's inclination, and then, still in atmosphere make a turn towards the target orbit's plane to create am optimal intersection, effectively enabling Off-Plane correction. The turn will be more efficient than an in-orbit plane change, because of much smaller velocity which you need in the atmosphere, and because the velocity vector will be changed by your wings' lift, not engine power. It will make even more sense, if you use DG-S, which is equipped with SCRAM engines.

Final distance selection for Direct Ascent
When the autopilot for regular DA is enabled, using (Shift A) or ALT button, you may enter the final distance to the target in meters. Positive values mean ending n meters above target and negative mean ending below the target. Notice that for reasons of realistic spaceflight, the positive values make less sense than negative, because you always approach the target from below, firing thrusters in the direction of target. If you intend to end up above the target, there would be a moment when you cross the altitude of the target, firing your exhaust right at the target.

Enjoy!
 
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Hello,

Would it be possible to allow entering a negative periapsis?

I'm trying to lob a payload into a precise sub-orbital trajectory. The payload ignites a solid at apoapsis to circularize its orbit. I need to launch to an initial orbit of
-1831 km x 700km. However, min allowed periapsis in LaunchMFD is zero.
 
Hi,

That's interesting, but I need to see if PEG stays stable in such setup.

---------- Post added at 04:16 PM ---------- Previous post was at 09:24 AM ----------

Unfortunately it's unstable and can't converge.
 
Neither the LaunchMFD nor the HUDDrawerSDK descriptions are clear on this point:

Does the latest version of LaunchMFD require the HUDDrawerSDK (presumably for the vesselhooking.dll)?

The description for LaunchMFD in Orbit Hanger looks like this :

"Works with Orbiter 2010 P1 only. Don't it use with Orbiter 2006. Launch MFD for Orbiter 2006 can be found here:
[ame="http://www.orbithangar.com/searchid.php?ID=4408"]Launch MFD - v. 1.6.1 for Orbiter 2006[/ame]
Additionaly requires HUDDr awer SDK."

What is not clear is whether it is the old version of LaunchMFD or all versions of LaunchMFD require the additional SDK.
 
The old version has its HUD drawer 2006 version embedded in the package, so in theory, you don't have to care about it.
 
The old version has its HUD drawer 2006 version embedded in the package, so in theory, you don't have to care about it.

I am sorry for what I am about to say, Enjo; but thanks very much for the reply.

It's difficult for me to understand non-literal context. What you said above does not answer my question, so I remain in the dark.
 
"The old version doesn't need it" then
I knew that this question would be asked some day. I also knew that the real answer (my previous post) wouldn't be of any help :)
 
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