OHM SpaceX launch vehicles and Dragon

[Grover]

all sounding good! ill give it a try in a bit

im gonna try and get an ISS launch scenario going with the dragon-4, cant imagine it should be too hard to swap out a single payload. and it should make for an easier ISS scenario since it has slightly more dV

---------- Post added at 10:27 AM ---------- Previous post was at 09:06 AM ----------

ok, one little bug

UMMU arent assigned their numeric properties correctly it seems.

their age becomes the slot in the craft the occupy
a random number (3,000,000 +) becomes their age
and their name always becomes "*&" or something like that

they work fine, but they dont seem to know who they are :S

 

[Wishbone]

Thanks for the update!

Glider, found some bugs in the old version that did not make it into changelog:

a) Propulsive landing AP makes the Dragon go like a ping-pong ball, bouncing up and down.
b) The Dragon capsule has some mighty engines not envisaged by Musk and Co.
c) The lateral linear RCS mix-up is a problem for Attitude MFD in the Kill velocity mode.
d) It may be dangerous to have Shift-J key work to jettison fairing in the Falcon but to jettison trunk in the Dragon. Suggestion - map Shift-J to fairing jettison in both Falcon and Dragon, and Shift-N to trunk jettison.
e) During solar panel deployment, all rotations (automatic as well as manual) should be inhibited (a known bug from prior releases, but there was nothing you could do in Spacecraft-based animations, now it can be fixed).
f) UMMus' definitions are not read from the file. As a feature request, it would be nice to have face meshes inside the capsule correspond to UMMu faces outside it.
g) Battery charge is not clamped to the 0-100 range, it starts to charge or discharge ONLY at x1 time acceleration, and may easily go above 100 or below 0.
h) The Dragon docs should be a bit more explicit on the re-entry profile. While aiming for Cape Canaveral with Aerobrake MFD, I ended up 1000 km short, in Memphis, Tennessee. No need to say I had to take a Greyhound back to Houston...

 

[Spicer]

Just a question. On the manned dragon capsule, there is no escape tower. Is the Dragon going to have a tower or a ring-based escape procedure? Just wondering. I finally got the add on working, and I love it!

 

[Jarvitä]

Just a question. On the manned dragon capsule, there is no escape tower. Is the Dragon going to have a tower or a ring-based escape procedure? Just wondering. I finally got the add on working, and I love it!

I believe the current plan is to use a combination of magic and onboard RCS propellant for a "push-type" abort system.

 

[N_Molson]

Just a question. On the manned dragon capsule, there is no escape tower. Is the Dragon going to have a tower or a ring-based escape procedure? Just wondering.

The Dragon has abort motors integrated to the capsule, that can be used to slow down the capsule on ground landing.

 

[Jarvitä]

The Dragon has abort motors integrated to the capsule, that can be used to slow down the capsule on ground landing.

So in case of a launch failure, the crew have to choose between surviving the LV explosion and surviving the landing? :facepalm:

 

[T.Neo]

I believe the current plan is to use a combination of magic and onboard RCS propellant for a "push-type" abort system.

That is not nice. How do you know what they plan to do with the abort system and how they plan to do it? Maybe the real "magic" bit is just the mystery behind it...

There has been interest in "pusher LAS" systems. There are issue with the concept, and it would be very nice if someone would explain how these would be solved...

So in case of a launch failure, the crew have to choose between surviving the LV explosion and surviving the landing?

There would be a parachute as backup, of course... :uhh:

 

[PhantomCruiser]

Launch escape is integrated into the control system. SpaceX has the goal of eventually using the engines to 'spot' land on the ground, that's in addition to the ability to make a water recovery.
In short, no there's not a tower for LES.

Ah, hurrah YouTube

 

[N_Molson]

So in case of a launch failure, the crew have to choose between surviving the LV explosion and surviving the landing?

The landing should be rough in that case, but survivable. But if you launch from the Cape, typically, it will be a water landing, that is a little softer.

 

[anemazoso]

My understanding is that the re-entry process would include the use of a drag chute prior to the final propulsive deceleration and landing so it wouldn't take much fuel for a soft landing. Correct me if I'm wrong.

 

[Glider]

Another update. Only three changes:
- K+Shift for fuel dump now doesn't interfere with K for animation.
- fixed wrong info for UMMUs. (now age, slot and name should be shown properly)
- Dragon controls changed: Shift+J - jettison fairing, Shift+N - jettison trunk.

a) Propulsive landing AP makes the Dragon go like a ping-pong ball, bouncing up and down.
....
h) The Dragon docs should be a bit more explicit on the re-entry profile. While aiming for Cape Canaveral with Aerobrake MFD, I ended up 1000 km short, in Memphis, Tennessee. No need to say I had to take a Greyhound back to Houston...

a. What was the type of Dragon ? was it reentry/launch abort ? I tried to reenter, do launch abort both on LPad or in flight and it always landed as it should: rotation->high thrust and when vertical speed == 0.0 -> low thrust(less than 1 g).
b. LES engines ? Why not envisaged ?
c. I think I've already fixed c. francisdrake said that ATT_LEFT and ATT_RIGHT were wrong, so I've changed directions of left and right linear thrusters in the previous update.
d. Changed.
e. I wasn't able to rotate SP during their deployment. Are you sure in this bug ?
g. should be fixed with the previous update.

 

[francisdrake]

Good update! The autopilot on the ride to orbit was much smoother now. Left-right linear attitude thrusters are corrected. Frame rate in orbit was much better now, ~25 fps. This addon includes an abundance of Falcon & Dragon combinations, I just tried the manned Dragon to ISS; looking forward to test-fly all the others
_____

A word on the pusher-type LAS: Yes, this may work. I did some calculations a while ago. Came up with 8 engines @ 95 kN each. They burn ~ 1 ton fuel in 2 seconds. This provides an initial separation acceleration of 72 m/s² (~ 7 g) and a delta v of 200 m/s (which is comparable to published figures of the Orion LAS).

An abort during a launch from KSC will most probably result in a water landing, so no landing thrusters are needed. But even on a hard surface an unpowered landing will be surviveable, although inconvenient.

 

[Grover]

it is well thought through... mainly becuase its a real life craft, many highly-paid designers have struggled over many aspects of the Dragon/Falcon. all that was left for glider to do
(though it is still hard at times) is to get reliable info, high quality meshes/textures (good work by the way ) and code it all together, which has been done beautifully!

 

[Wishbone]

Glider, thanks again, will d/l and try out the revised version this week. The off-nominal (bouncing) re-entry occurred because a) I was fighting the autopilot, b) there was too much fuel. Will try to replicate the conditions for the defect. As I re-entered with the right amount of fuel and without battling the default autopilot, the Dragon performed admirably (however, Load MFD showed 72G at touch-down... this sort of discontinuities can be Orbiter's fault, though).

Re: solar panels - yup, the panels looked weird (one pane 1 meter above the other with struts out of place) in this release after I pressed S _before_ deployment. Saving and restoring fixes that since stored animations are presented the correct way.

 

[Grover]

72G for touchdown could be correct, since its technically an infinite acceleration because there is no shock absorption in any landing gear, you lose all your vertical speed in an instant... therefore 72G for an instant sounds about right i think

 

[N_Molson]

It seems that the crew data isn't saved.

I added a crew of 7 prior to launch, using the "M" key, and the capsule filled with the orange-blue 'nauts as I hoped.

Then I launched the spacecraft to LEO and saved. When I reloaded, the crew was gone... "Nobody on board". :hmm:

Has someone else experienced this ?

 

[Interceptor]

Yes Molson, I have experienced the same problem with the ummu,and also with ucgo cargo too,with this addon.

 

[Wishbone]

Yup, already reported. It looks like a parsing error (been there done that :blush.

 

[sorindafabico]

Hi, this is my first post in O-F. I'm from Brazil and I play Orbiter since last year.

Great addon! But Falcon Heavy has a couple of bugs: I tried to launch a Dragon (both manned and cargo) to the Moon. After TLI, the second stage (with some fuel yet) becomes trash randomly.

The FH's autopilot has a problem too, I set apoapsis to values like 200~250km, but the first stage goes a little crazy just before MECO and apoapsis ends at +-400km. Falcon 9's autopilot is fine (I didn't test the others) and works well.

 

[Wishbone]

sorindafabico, can confirm the TLI bug - I tried to send the second stage to Mars and beyond after a successful payload separation (on FPR fuel ), and it indeed became "Trash".