Project SpaceX SuperHeavy

[Marijn]

Hmm, so for the De-orbit burn I link BaseSyncMFD with Glide slope MFD. Since I am puzzled now.

You can use BaseSyncMFD standalone for this. Just enter the three numbers mentioned above, turn the ship retrograde and burn the amount of seconds indicated by BaseSync.

 

[BrianJ]

Updated on OH: v.210521
RCS linked to Main Propellant Tanks.
RCS Propellant Tanks removed - propellant tank indexes changed, saved scenarios may not load propellant correctly.
New RCS exhaust visuals.
Vessel names changed to "Starship" in scenarios, propellant entries updated.
Readme doc revised.

Note - I tried "overloading" the Tanker variant with extra fuel, but performance was actually worse - 100T to 130T fuel payload seems to be optimum.

 

[MarkWatney2015]

Note - I tried "overloading" the Tanker variant with extra fuel, but performance was actually worse - 100T to 130T fuel payload seems to be optimum.

Makes sense, the tankers after all have the same payload capacity as the Cargo/Crew versions anyway

 

[MarkWatney2015]

But the circular arrangement and gigantic size of the Booster remembers me of the N1.
I really really hope the Raptors perform well.

Starship's advantages over the N1 is that the Raptors can be put into static fire tests, both individual and group, and then later be used on actual launches, whereas the NK-15 engines of the N1 had to be replaced entirely once fired. There's no way of telling on the N1 which engine it uses is defective

 

[francisdrake]

Thanks for the update! It is much fun to fly!
This time I managed docking to the tanker in the double-launch scenario on the first try. Although with less than expected fuel remaining, which is probably due to my point-and-go docking approach.

Really challenging is that the RCS controls are mostly inverted when looking backwards while approaching the aft docking port of the tanker. This took my armchair piloting skills to test.

On the fuel payload I guess the tankers will just have bigger tanks, so the tanking will consume the remaining fuel, minus the fly-back reserve.

 

[Marijn]

A few things:
-I am only seeing the RCS visuals from the external view now. Not from the main forward view anymore. Not sure if that is intentional?
-Dumping the 2nd stage fuel now also leads to zero RCS fuel, while you need some for the landing. So this has become a little harder to manage. Maybe implemend some lower limit to keep some fuel aboard?
-I also would like the option to have the trim controls reversed. I prefer pulling back on the stick (down arrow) to increase the AoA, like normal aircraft. I keep pressing the wrong buttons when controlling the trim.

Thanks for your efforts!

 

[Sbb1413]

Starship's advantages over the N1 is that the Raptors can be put into static fire tests, both individual and group, and then later be used on actual launches, whereas the NK-15 engines of the N1 had to be replaced entirely once fired. There's no way of telling on the N1 which engine it uses is defective

While Super Heavy will have more engines than N1 (37-ish compared to 30 of N1), the former may perform much greatly than the latter, which was boomed four times. Therefore, I don't have to hear the stereotype "more engines more problems" anymore.

 

[BrianJ]

Thanks for the update! It is much fun to fly!
This time I managed docking to the tanker in the double-launch scenario on the first try. Although with less than expected fuel remaining, which is probably due to my point-and-go docking approach.

Really challenging is that the RCS controls are mostly inverted when looking backwards while approaching the aft docking port of the tanker. This took my armchair piloting skills to test.

On the fuel payload I guess the tankers will just have bigger tanks, so the tanking will consume the remaining fuel, minus the fly-back reserve.

Yes, not so easy to dock facing backwards. I could try an option to reverse the pitch and yaw rotation, and fwd/back and left/right translation RCS. Didn't the SpaceShuttle have something like that?

re:Tanker - I calculated you could get another ~400T LOX/Methane into the payload bay, so tried enlarging the fuel payload tank to that size and linking the main engines to it after main tank depletion, but actually ended up with less than 100T remaining. Gravity losses on the way up?

A few things:
-I am only seeing the RCS visuals from the external view now. Not from the main forward view anymore. Not sure if that is intentional?
-Dumping the 2nd stage fuel now also leads to zero RCS fuel, while you need some for the landing. So this has become a little harder to manage. Maybe implemend some lower limit to keep some fuel aboard?
-I also would like the option to have the trim controls reversed. I prefer pulling back on the stick (down arrow) to increase the AoA, like normal aircraft. I keep pressing the wrong buttons when controlling the trim.

Thanks for your efforts!

No way to control cockpit view of RCS visuals as far as I know - I guess the exhaust plume is just a bit smaller, or something.

RCS are also linked to Landing Reserve Fuel tank, so if you switch over to that then RCS should work.

Maybe I can have an option to reverse Wing Trim controls also.

Cheers,
Brian

 

[ChrisRowland]

Apparently the first booster will have 29 raptors, an extra one in the center. Later this will increase to 32. This can be done with a ring of 4 in the center, then rings of 8 and 20.

This is based on a thrust puck being seen at Boca Chica and an Elon tweet. He's also talking about increased thrust (7,500 t?) and a thrust to weight ratio of 1.5.

Just seen another ElonTweet, 3 in the center, then 9 and 20. The inner 12 gimbal. May be better to wait and see. Get the impression that 12 are used for the boostback.

 

[BrianJ]

Apparently the first booster will have 29 raptors, an extra one in the center. Later this will increase to 32. This can be done with a ring of 4 in the center, then rings of 8 and 20.

This is based on a thrust puck being seen at Boca Chica and an Elon tweet. He's also talking about increased thrust (7,500 t?) and a thrust to weight ratio of 1.5.

Just seen another ElonTweet, 3 in the center, then 9 and 20. The inner 12 gimbal. May be better to wait and see. Get the impression that 12 are used for the boostback.

Hi Chris,
thanks for the updates. I don't tweet or go to NSF much, so I miss these things. I'm having fun with reentry autopilot for the upper stage at the moment, booster updates are on the back-burner anyway. 32 engines, thrust/weight of 1.5 - monstrous!
Cheers,
Brian

 

[Challenger007]

Hi Chris,
thanks for the updates. I don't tweet or go to NSF much, so I miss these things. I'm having fun with reentry autopilot for the upper stage at the moment, booster updates are on the back-burner anyway. 32 engines, thrust/weight of 1.5 - monstrous!
Cheers,
Brian

Monstrous in a good or bad way? After all, if humanity plans to send a human crew into space (for example, to Mars), then the spacecraft must be very powerful in order to overcome the force of gravity and gain sufficient speed to enter orbit and travel in space.

 

[BrianJ]

Monstrous in a good or bad way? After all, if humanity plans to send a human crew into space (for example, to Mars), then the spacecraft must be very powerful in order to overcome the force of gravity and gain sufficient speed to enter orbit and travel in space.

"Monstrous" in a large way ;-)

 

[Kyle]

Here's the configuration of the engines as confirmed by Elon: https://i.redd.it/cd9r23o9wd271.png

 

[BrianJ]

Here's the configuration of the engines as confirmed by Elon: https://i.redd.it/cd9r23o9wd271.png

Thanks

 

[Kyle]

Elon has confirmed no entry burn for Super Heavy, just a landing burn.

https://twitter.com/x/status/1410325315835109378

 

[BrianJ]

Thanks. Quite astonishing to me!
btw I'm still struggling with trying to get some kind of re-entry autopilot working for the upper stage.

 

[Kyle]

Tons of juicy details for you, Brian.

First: Probable Starship orbital attempt TLEs.

https://twitter.com/x/status/1411792020105043968

Second: Elon has dropped specs on booster thrust and Raptor performance:

https://twitter.com/x/status/1411794332340740099

 

[BrianJ]

Thanks. Like J.McDowell, I suspect the Starship will be launched on an eccentric ~50km x 250km orbit, with orbit insertion somewhere in between PeA/ApA. No de-orbit burn required. I haven't implemented that kind of launch profile for the SuperHeavy add-on launch autopilot, but it might be possible to use BaseSyncMFD or IMFD "Base Approach" immediately after SECO to set up that trajectory. Will have a look at booster specs later ;-)
Cheers,
Brian

 

[BrianJ]

I just tried a little experiment with the "Flight Test 1" scenario and IMFD "Base Approach" with a quite interesting result - a 50km x 590km orbit. Any tweets from Elon about maximum altitude for the flight profile?

Here's my settings and method:
Set the "SuperHeavy" launch controls for PeA 160km, ApA 200km.

Set IMFD "Base Approach" to the LZ_KAUAI vessel long. and lat. : -160.12, 22.82
ReA 1.5
Alt 120km
Ant 45.0
Hint 5000s

Launch "SuperHeavy" using the launch autopilot.

Just before SECO, at about 157km alt turn off the Starship launch autopilot, kill the engine, and hit IMFD "Base Approach" autoburn [AB].

You can even give my (very clunky) reentry autopilot a try - use new starship.dll in the attached .zip
Press U for reentry autopilot from 120km. (it does like to "overfly" target at the moment).

Cheers,
Brian

 

[Marijn]

You can even give my (very clunky) reentry autopilot a try - use new starship.dll in the attached .zip
Press U for reentry autopilot from 120km. (it does like to "overfly" target at the moment).

Sure pressing U should work? I don't notice anything happening. I don't see 'U' listed as a button on the HUD either. Any idea what I could do wrong maybe?