Author Topic: Speculation: what will be the first ITS hardware to fly?  (Read 4710 times)

Offline Kaputnik

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There's a lot of discussion on the main thread about the ITS develoment, and precious little information to go on.
One thing that stands out is that different commentators have different ideas about how we can expect the development to proceed- particularly whether there will be a 'mini ITS', subscale Raptor, or Raptor-on-Falcon upgrade.

So my question is- what do you think will be the first flight in support of ITS develoment? By this I mean any flight that directly contributes towards the ITS project, be it an engine, materials, aerodynamic profile, a landing manoeuvre, etc etc.
Something like the first flight of FH would not count, but a Raptor upgrade, a switch to composite tanks, a landing cradle, all would.
I don't think Red Dragon would count as that is not really ITS hardware, although it is relevant to the overall project. YMMV.

My own guess: a variant of the BFS, probably with representative aerodynamics, reduced engine count, and higher dry mass. This would be flown suborbital in a grasshopper style program to verify in-atmosphere aero loads and landing software. It would be full size but probably not utilise the full composite construction of the production design.
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Offline stcks

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #1 on: 04/14/2017 01:00 PM »
If the big CF lox tank is any indication (probably not) then it would be the ITS first.

Offline Robotbeat

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #2 on: 04/14/2017 01:05 PM »
Falcon Heavy demo flight. Whatever method of reuse they try, they will be retiring risk for the ITS spaceship.
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Offline Lar

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #3 on: 04/14/2017 01:26 PM »
Falcon Heavy demo flight. Whatever method of reuse they try, they will be retiring risk for the ITS spaceship.

I agree with this... especially if there is any sort of S2 experiment, whatever form it takes.... but I suspect the way the OP defined it, they would not.
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Offline Kaputnik

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #4 on: 04/14/2017 02:44 PM »
Falcon Heavy demo flight. Whatever method of reuse they try, they will be retiring risk for the ITS spaceship.

Ha! I knew someone would bring this up! Wasn't sure how to categorise it- they might have chosen this route for Falcon regardless of ITS development needs. So I suppose the clincher would be if the predominant driver for the test is for BFS design validation, or if it's mostly about developing a reusable F9 US. And of course you can argue that the two go very much hand in hand.

If that's the first step... then what comes next?
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Offline Xaryen

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #5 on: 04/14/2017 03:05 PM »
Technically, the experimental composite tank has already "flown" on its own.

Offline Lar

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #6 on: 04/14/2017 03:25 PM »
Technically, the experimental composite tank has already "flown" on its own.

ha. It wasn't that successful of a test flight though. More of a RUD.  I am still hoping to hear serious ideas on this topic, it is fascinating.
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Online jpo234

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #7 on: 04/14/2017 03:27 PM »
The "Next Steps" slide from the IAC presentation lists ship testing followed by booster testing.
« Last Edit: 04/14/2017 03:27 PM by jpo234 »

Offline philw1776

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #8 on: 04/14/2017 06:45 PM »
The "Next Steps" slide from the IAC presentation lists ship testing followed by booster testing.

My initial reaction was "That's backwards" but upon reflection, building a proto ITS with sea level Raptors, maybe not more than say 4 engines initially, gets flight experience without manufacturing dozens of Raptors for even a depleted booster stage that will get change ordered to death with early flight feedback.
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Offline ncb1397

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #9 on: 04/14/2017 06:56 PM »
The "Next Steps" slide from the IAC presentation lists ship testing followed by booster testing.

It also puts that milestone at 16 months from now. Does SpaceX have a secret volcano lair where all this work is happening?
« Last Edit: 04/14/2017 07:10 PM by ncb1397 »

Offline Coastal Ron

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #10 on: 04/14/2017 07:18 PM »
The "Next Steps" slide from the IAC presentation lists ship testing followed by booster testing.

It also puts that milestone at 16 months from now. Does SpaceX have a secret volcano layer lair where all this work is happening?

Hasn't Elon Musk shown that he can do more than one thing at a time?  Who knew they were building a composite LOX tank for ITS testing until we saw a picture of it?

Musk has not perfected his space-time dilation techniques, but he has shown that when he says he plans to do something that he's already looked into seeing if it's possible - and he's obviously OK with being derided publicly if they don't make his wish dates.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Online dkovacic

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #11 on: 04/14/2017 08:58 PM »
I think that the first ITS flight variant will be SSTO without BFR. It can fly itself to the orbit, leave some usable payload in LEO and perform reentry. Thus it can earn money AND build flight heritage AND do reentry/reusability/endurance testing.

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Offline Robotbeat

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #12 on: 04/14/2017 11:47 PM »
SSTnotquiteO, more likely. Like X-33 kinda. Perfectly acceptable for testing.
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Offline Kaputnik

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #13 on: 04/15/2017 12:36 AM »
I think that the first ITS flight variant will be SSTO without BFR. It can fly itself to the orbit, leave some usable payload in LEO and perform reentry. Thus it can earn money AND build flight heritage AND do reentry/reusability/endurance testing.

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My understanding is that the BFS can get to orbit but would be stuck there. You'd have to concoct some hairbrained scheme partially refuelling it using Falcon launches if you wanted it back. Hardly likely to be an economical launch vehicle in its own right.
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Offline OneSpeed

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #14 on: 04/15/2017 12:53 AM »
My understanding is that the BFS can get to orbit but would be stuck there. You'd have to concoct some hairbrained scheme partially refuelling it using Falcon launches if you wanted it back. Hardly likely to be an economical launch vehicle in its own right.

A BFS tanker with all sea level engines has a theoretical ΔV of about 11km/s. It could get to orbit and land. There is a summary of some options that have been simulated here: https://forum.nasaspaceflight.com/index.php?topic=42003.msg1635249#msg1635249
« Last Edit: 05/04/2017 01:24 PM by OneSpeed »

Offline brickmack

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #15 on: 04/15/2017 01:18 AM »
My guess at the testing path:

1. Falcon-Raptor, in-flight demonstration of Raptor and testing of something approximating the Spaceship landing profile

2. ITS-Spaceship-Dev1. 3 engine Spaceship semi-boilerplate,  flies partially filled for short hops (<1 km), validates final landing targeting on unprepared terrain, leg design, large-scale flight-qualified composite tanks

3. ITS-Spaceship-Dev2. Nearly-complete copy of a tanker-variant ship, but with 9 SL Raptors to allow it to take off fully fueled. Flies first on a New Shepard style trajectory, then expanding to a near-orbital trajectory (with downrange landing). Tests aerodynamics on reentry, heat shielding, landing from high velocity, attitude control during coasts, propellant dynamics, near-complete propulsion system.

4. ITS-Booster-Dev. Shortened booster, same diameter, fewer engines. Flies with non-retracting legs (like the original Grasshopper) at first to validate landing control, then moves on to a landing cradle. Short hops only

5. ITS Booster, final design but with nose cap mass simulator. Just 1 flight, validates entire booster mission profile

6. ITS Tanker to orbit. Likely dozens of flights, some carrying paying payloads. Proves full launch and reentry profile, medium-term LEO coast (days-weeks), orbital maneuvering, rendezvous/docking, propellant transfer, rapid reuse, overall reliability

7. Spaceship to orbit, unmanned to prove equipment not tested on tanker.

8. Spaceship to lunar orbit and back. Proves full refueling campaign, high velocity reentry

9. Manned spaceship to orbit, routine crew flights within the Earth-moon system begin

10. First ITS to Mars, proves full cargo mission profile and carries critical hardware for the base

Offline Kaputnik

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #16 on: 04/18/2017 07:18 AM »
Another thought:
What would be the largest payload that could be placed on top of a FH core+boosters stack?
Using their existing heavy launcher, SpaceX could fly a subscale ITS stage as a reusable combined US/payload, and validate the OML. If adding CH4 to thr pad was possible, then it could also test fly the Raptor- otherwise it would use Merlins.
This would get flight experience on a large lifting body, without needing to build the BFR and its pad first.
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Offline OneSpeed

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #17 on: 04/18/2017 12:16 PM »
Another thought:
What would be the largest payload that could be placed on top of a FH core+boosters stack?
Using their existing heavy launcher, SpaceX could fly a subscale ITS stage as a reusable combined US/payload, and validate the OML. If adding CH4 to thr pad was possible, then it could also test fly the Raptor- otherwise it would use Merlins.
This would get flight experience on a large lifting body, without needing to build the BFR and its pad first.

Yes, and there is a simulation of it here: https://forum.nasaspaceflight.com/index.php?topic=42336.msg1646574#msg1646574
With the latest FH specifications, it should get a 100% reusable 40mT+ payload to LEO, and if the half scale BFS used 6 or 7 half scale Raptors, the centre one could be throttled low enough to land it.

Offline DreamyPickle

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #18 on: 04/18/2017 12:44 PM »
I think the first flight will be a full-size ITS tanker doing suborbital hops (Grasshopper-style).

Offline Kaputnik

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #19 on: 04/18/2017 12:47 PM »
Another thought:
What would be the largest payload that could be placed on top of a FH core+boosters stack?
Using their existing heavy launcher, SpaceX could fly a subscale ITS stage as a reusable combined US/payload, and validate the OML. If adding CH4 to thr pad was possible, then it could also test fly the Raptor- otherwise it would use Merlins.
This would get flight experience on a large lifting body, without needing to build the BFR and its pad first.

Yes, and there is a simulation of it here: https://forum.nasaspaceflight.com/index.php?topic=42336.msg1646574#msg1646574
With the latest FH specifications, it should get a 100% reusable 40mT+ payload to LEO, and if the half scale BFS used 6 or 7 half scale Raptors, the centre one could be throttled low enough to land it.

Thanks, I had forgotten about that. Neat, but the argument against is that it's a huge development project in its own right. Perhaps a Merlin powered version would be more likely? Serving a similar role that Enterprise did for STS. But perhaps we have good enough computer modelling now that such a thing is not needed.

Another thought is that the FH US/payload should total around 175t, and the dry mass of the BFS is supposed to be 150t- and the tanker presumably a bit less than that. So in fact it would be, in theory, possible to launch a short-fuelled full size BFS onto a suborbital trajectory. The aero loads for the poor little Falcon would perhaps be too much, and operating the BFS as a single stage suborbital (or even orbital) vehicle is probably more likely- but it's fun to run through the different options.
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Offline envy887

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #20 on: 04/18/2017 12:53 PM »
Another thought:
What would be the largest payload that could be placed on top of a FH core+boosters stack?
Using their existing heavy launcher, SpaceX could fly a subscale ITS stage as a reusable combined US/payload, and validate the OML. If adding CH4 to thr pad was possible, then it could also test fly the Raptor- otherwise it would use Merlins.
This would get flight experience on a large lifting body, without needing to build the BFR and its pad first.

I don't think that upper stage mass would be the limiting factor. Peak stresses are almost certainly in flight, not sitting on the pad, and flight stresses might actually go down with a larger upper stage because the vehicle accelerates slower and hits trans-sonic and MaxQ later and higher in the atmosphere. Wind shear is also less stressful due to lower speeds in the dense part of the atmosphere.

IMO, bending moments from a large upper stage under aero loads will be the limiting factor.

Offline envy887

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #21 on: 04/18/2017 12:57 PM »
...
Another thought is that the FH US/payload should total around 175t, and the dry mass of the BFS is supposed to be 150t- and the tanker presumably a bit less than that. So in fact it would be, in theory, possible to launch a short-fuelled full size BFS onto a suborbital trajectory. The aero loads for the poor little Falcon would perhaps be too much, and operating the BFS as a single stage suborbital (or even orbital) vehicle is probably more likely- but it's fun to run through the different options.

A BFS would look preposterous sitting on top of Falcon Heavy. Falcon Heavy boosters next to a BFS might work, but are entirely unnecessary if the goal is suborbital flight.

Offline OneSpeed

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #22 on: 04/18/2017 01:07 PM »
Neat, but the argument against is that it's a huge development project in its own right.

It would be a logical first step in the ITS development process, and retire many risks early. It would have one eighth of the material costs, and potentially be a money earner in the shorter term. That is why it is a good candidate for the first ITS hardware to fly. The updated SpaceX plans for ITS can't come soon enough ;)
« Last Edit: 04/18/2017 09:29 PM by OneSpeed »

Offline guckyfan

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #23 on: 04/18/2017 01:24 PM »
Coming back to a methane upper stage for F9/FH. Just one Raptor vac, scaled or full size. Make it the weight of the present upper stage, so slightly more diameter, but same height. How much can the TE take without shape modification? 50 or 60cm more diameter should do it. Carbon fiber body, autogenous pressurized. With the winglike extensions of ITS or without, but with the flaps. Nozzle extension small enough to fit into the existing interstage.

This should give the reusable upper stage for F9 and FH without payload penalty for most orbits plus plenty of ITS related experience. It could even fit the end of next year timeline for reusable upper stage, or almost, if they have been working the idea for a while.

Offline OneSpeed

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #24 on: 04/18/2017 09:44 PM »
Coming back to a methane upper stage for F9/FH. Just one Raptor vac, scaled or full size. Make it the weight of the present upper stage, so slightly more diameter, but same height. How much can the TE take without shape modification? 50 or 60cm more diameter should do it. Carbon fiber body, autogenous pressurized. With the winglike extensions of ITS or without, but with the flaps. Nozzle extension small enough to fit into the existing interstage.

This should give the reusable upper stage for F9 and FH without payload penalty for most orbits plus plenty of ITS related experience. It could even fit the end of next year timeline for reusable upper stage, or almost, if they have been working the idea for a while.

Everything in the current launch process assumes a 3.66mØ rocket, including tooling, road transport, and the TE. If you are going to change all of those, why not go straight to a half scale (6mØ) BFS, and learn a lot more?

Also, the split body flaps would be integrated with the strakes, not a separate option.

Offline guckyfan

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #25 on: 04/18/2017 09:59 PM »
Road transport is not important for reusable stages. The airframe would be produced where ITS would be produced later. I was suggesting a very moderate diameter increase, just enough that the same propellant weight fits. The idea being that the TE does not need modifications. If I am wrong and the TE can really not handle 50cm additional diameter, that would be 25cm/10 inch closer to the TE, then indeed the idea is not feasible. But that is why I am not suggesting something much larger, optimized for FH.

The idea is just getting experience with the new materials and technology and at the same time gaining enough performance to compensate for reusability losses, no more.

Offline Paul451

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #26 on: 04/19/2017 11:26 AM »
Hard to imagine that SpaceX would hesitate to modify the TE again, if they thought a wider diameter upper-stage had a market.



Generally:

No methalox launch vehicles smaller than ITS. No Raptors smaller than the ITS-version. No intermediate-sized versions of anything. (This is not my preference. I'd prefer them to go the other way, but I see nothing to suggest they will.)

[Exception: if someone like the USAF wants to pay (directly or through significant contract launches) for an upper-stage development, and Musk thinks there's a profit in it. He'll use it to further practice building recoverable upper-stages, vacuum versions of Raptor, etc.]

First, a dumb but full-diameter variant of the ITS-Orbiter created within 2yrs as a Grasshopper (more like a kangaroo) to test engines and landing systems, eventually to test the recovery cradle. This is the first vehicle that Musk referred to.

Then the ITS-Booster, possibly skipping right past a Grasshopper test-vehicle step for that. This tests the launch infrastructure. If the ops cost is comparable with the multi-core complexity of FH, ITS will immediately replace FH as SpaceX's heavy lift launch vehicle. Let customers pay for recovery tests. (If not, no harm done.)

(I suspect the first version of the recovery/capture system will be separate from the launch pad. Same site, but far enough apart that a failed landing doesn't take out the launch pad.)

Then a simplified cargo-carrying ITS-Orbiter, launching on the ITS-Booster, for launch & recovery tests.

Then the ITS-Tanker, that allows orbital docking tests and higher-rate ground-ops practice. Now they have the parts necessary to deliver a payload or two to surface of Mars. I suspect they'll test a couple of versions of their fuel-production system in-situ, rather than try to sim everything to death on Earth. But its likely this flight (or flights) will be sold to someone like NASA, early 2020's for a next-gen rover, sample-return missions, etc, letting SpaceX effectively fly their test missions for free.

Then a man-rated version of the ITS-Orbiter, flown into space a couple of times to test, maybe flown unmanned to Mars once. Maybe. But the moment SpaceX is comfortable with the orbital propellant transfer system, the in-situ Martian propellant manufacturing system, and the reliability of the manned Orbiter, they will fly humans to Mars. Even if the early versions can only support a handful of people for a short-duration mission, they'll fly volunteer researchers and bring them back. (And I suspect they'll be able to sell seats to existing agencies.)

[Nomenclature: ITS (the whole thing). ITS-Orbiter (AKA "BFS", the top bit). ITS-Tanker (the other version of the top bit). ITS-Booster (AKA "BFR", the bottom bit.)]

Offline guckyfan

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #27 on: 04/19/2017 11:57 AM »
Hard to imagine that SpaceX would hesitate to modify the TE again, if they thought a wider diameter upper-stage had a market.

They will not want to cause significant downtime. The TE will need to be modified to carry methane for the new upper stage. But it would need to be compatible with the existing upper stage for a while.

Offline Robotbeat

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #28 on: 04/19/2017 01:21 PM »
They've probably built at least 10 different variants of the TE. I remember that in the early days it seemed they used a new TE variant for every launch.
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Offline spacenut

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #29 on: 04/19/2017 01:51 PM »
Does anyone have an idea of the time frame for any of SpaceX's equipment?  Raptor?  Raptor vacuum?  ITS? BFR? 

Offline guckyfan

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #30 on: 04/19/2017 01:53 PM »
They've probably built at least 10 different variants of the TE. I remember that in the early days it seemed they used a new TE variant for every launch.

Yes, we all remember the downtime. Or the time between flights. They will not want that back.

Offline Kaputnik

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #31 on: 04/19/2017 03:31 PM »

First, a dumb but full-diameter variant of the ITS-Orbiter created within 2yrs as a Grasshopper (more like a kangaroo) to test engines and landing systems, eventually to test the recovery cradle. This is the first vehicle that Musk referred to.

The BFS doesn't land on a cradle, it has legs. Are you suggesting they might make a one-off version that would be different?
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Offline philw1776

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #32 on: 04/19/2017 04:05 PM »
1) ITS boilerplate.  Maybe aluminum.  Purpose to test SL Raptors.  Grasshopper style flights.  Maybe 3 Raptors.
Tests methalox engines in flight and some avionics.

2) ITS prototype with design goal carbon-fiber tanks & skin.  Rvac & SL Raptors, flies downrange & back RTLS.
Completes Block 1 Raptor engine design validation for build out & qualifies basic tank & airframe technology.

3) Booster prototype with ~21 engines. Inner ring & central cluster.  Flies downrange & RTLS but not on cradle for initial flights; temporary "legs".  Followed by cradle landing tests.

The goal of this approach is to allow rapid prototyping and flight experience without large expense building lots of early prototype engines that get ECOed and discarded.

4) Booster with ~21 engines with ITS (minimal "payload") 6 Rvac & 3 SL engines to LEO.
I've run #s based on Musk's September reveal and a 21 Raptor booster lifts a low payload ITS to LEO.
ITS orbital velocity re-entry qualified.

5) All-up all engines testing to LEO with ITS tanker re-fueling.  5b: Possible crew config ITS around the moon flight ECLSS etc. qualification.

6) Un-crewed cargo ITS re-fueled in LEO; lands on Mars with cargo, e.g. in-situ propellant equipment.
« Last Edit: 04/19/2017 04:08 PM by philw1776 »
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Offline envy887

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #33 on: 04/19/2017 04:46 PM »
1) ITS boilerplate.  Maybe aluminum.  Purpose to test SL Raptors.  Grasshopper style flights.  Maybe 3 Raptors.
Tests methalox engines in flight and some avionics.

2) ITS prototype with design goal carbon-fiber tanks & skin.  Rvac & SL Raptors, flies downrange & back RTLS.
Completes Block 1 Raptor engine design validation for build out & qualifies basic tank & airframe technology.

3) Booster prototype with ~21 engines. Inner ring & central cluster.  Flies downrange & RTLS but not on cradle for initial flights; temporary "legs".  Followed by cradle landing tests.

The goal of this approach is to allow rapid prototyping and flight experience without large expense building lots of early prototype engines that get ECOed and discarded.

4) Booster with ~21 engines with ITS (minimal "payload") 6 Rvac & 3 SL engines to LEO.
I've run #s based on Musk's September reveal and a 21 Raptor booster lifts a low payload ITS to LEO.
ITS orbital velocity re-entry qualified.

5) All-up all engines testing to LEO with ITS tanker re-fueling.  5b: Possible crew config ITS around the moon flight ECLSS etc. qualification.

6) Un-crewed cargo ITS re-fueled in LEO; lands on Mars with cargo, e.g. in-situ propellant equipment.

Part 1 isn't necessary. All the relevant testing can be done on the test stand.

I think part 2 will be the first ITS hardware to fly (unless a FH upper stage appears). Might include downrange landings until the flight and landing characteristics of the ITS ship are verified.

Part 3 is also unnecessary, there is no reason to launch the booster without an upper stage.

Part 4 would be a natural step, much like building a F9 v1.0 before jumping to the final Falcon 9. Could use fewer and derated Raptors, and the same tanks as the upper stage. They could even crew-rate this "short" ITS booster and start cislunar and Mars flights with it. Fully reusable payload should be ~175t to LEO launching the crewed upper stage and ~225t to LEO launching the tanker upper stage.

Offline oldAtlas_Eguy

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #34 on: 04/19/2017 07:05 PM »
If the ITS has the thrust to weight ratio to liftoff the ground with 0 payload, then a flight of just the ITS without the 1st stage BFR to sub-orbital or orbital once around test flight to test the ITS systems and it's ability to reenter and land.

Once a ITS can do this then they would be ready to build and test the BFR. Then the full stack 0 payload or even a possibility of the ITS being the tanker version is sent to LEO with its tanks full.

Followed by another BFR/ITS launch this time a cargo/personnel one loaded with cargo (or payload simulators at 1/4 total payload mass simulating the payload that the ITS would have on it's return from Mars) would then refuel from the tanker go to a higher orbit and then perform a high velocity reentry (not quite Mars return speed but much higher than just a LEO return).

Now all the elements except the long duration to Mars, Mars landing, and Mars liftoff with return journey to Earth has been tested.

Offline sanman

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #35 on: 04/25/2017 08:15 PM »
So are there going to be Grasshopper-style test flights for ITS? Will they likely start at McGregor?

Offline envy887

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Re: Speculation: what will be the first ITS hardware to fly?
« Reply #36 on: 04/25/2017 08:31 PM »
So are there going to be Grasshopper-style test flights for ITS?

IMO yes. That's my take based on the IAC presentation.

Quote
Will they likely start at McGregor?

Probably not. I think McGregor has some noise and altitude restrictions that would make that kind of testing more difficult. Check the past McGregor threads, there's more of a discussion there.

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