LIVE: SpaceX - Falcon I (Mk.II) NET March 20 (Attempt 2)

[Danderman]

aero313 - 28/3/2007  10:11 AM  The way mission design works is that the candidate launch vehicle (or possibly multiple vehicles for backup) is selected.  That fixes the total mission throw weight to a particular orbit.  The satellite designer (at least a GOOD satellite designer) will hold some performance back as margin against unforseen weight growth.  A good launch vehicle provider will do the same, by the way.  At the launch pad, the satellite will often come in under the max capability of the booster, thus the room for a secondary payload.  Again, this is done on a space available basis.

This works extremely well in theory, but maybe not so much in practice.

The satellite contractor will typically ensure that their propellant tanks can hold as much as the selected launch vehicle can handle plus margin. This margin, however, must cover such issues as variance from optimal launch windows, and even to some degree, launch vehicle injection accuracy. So, when does the 100 kg satellite customer know when that margin is available?

There is a reason why most successful commercial GEO comsat launch vehicles do not accommodate secondary payloads.

 

[Jim]

Danderman - 28/3/2007  2:21 PM

aero313 - 28/3/2007  10:11 AM The way mission design works is that the candidate launch vehicle (or possibly multiple vehicles for backup) is selected.  That fixes the total mission throw weight to a particular orbit.  The satellite designer (at least a GOOD satellite designer) will hold some performance back as margin against unforseen weight growth.  A good launch vehicle provider will do the same, by the way.  At the launch pad, the satellite will often come in under the max capability of the booster, thus the room for a secondary payload.  Again, this is done on a space available basis.

This works extremely well in theory, but maybe not so much in practice.

The satellite contractor will typically ensure that their propellant tanks can hold as much as the selected launch vehicle can handle plus margin. This margin, however, must cover such issues as variance from optimal launch windows, and even to some degree, launch vehicle injection accuracy. So, when does the 100 kg satellite customer know when that margin is available?

There is a reason why most successful commercial GEO comsat launch vehicles do not accommodate secondary payloads.

Neither are right.  

Most GTO launches (Delta IV, Atlas V, Zenit-3SL, etc) the customer gets all the performance.  The LV will burn to depletion and either put the spacecraft in a supersynchronous orbit or reduce inclination.  Either way, this allows the spacecraft to have more fuel onboard.  

With dual payloads, Ariane is like the shuttle and holds the reserve and so they are the ones who determine want to do with the excess performance.

[Danderman]

More on SpaceX:

Link to the most current manifest: http://spacex.com/launch_manifest.php

Attached is the SpaceX manifest from almost a year ago, about a month after the failure of the first launch. Among the interesting changes:

NRL, slipped from Q4 2006 to Q3 2007 (4 quarters).

Malaysia, slipped from Q1 2007 to Q4 2007 (3 quarters)

US government Falcon 9 demo: slipped from Q4 2007 to Q2 2008 (3 quarters)

Bigelow Aerospace F9: slipped from Q2 2008 to Q3 2010 (8+ quarters)

MDA Corp Kwaj F9: Q2 2008 no slip

MDA Corp Vandenberg F1: Q3 2008 to Q3 2009 (4 quarters)

SpaceDev F1: Q4 2008 to Q1 2009 (1 quarter)

Swedish Space Corp Vandenberg F1:  Q4 2008 slipped to Q4 2009 (4 quarters)

Some notes:

Both Vandenberg launches have slipped one year in the last year. Probably the range issues there are serious as a result of the launch failure last year.

3 NASA demo missions have been added. The first mission is scheduled for Q3 2008, a slip of one quarter from the Space Act agreement signed last summer.

Bigelow Aerospace's big slip is probably not related to SpaceX technical issues.

The Falcon 9 schedule has experienced major delays. Its not clear if these are related to Falcon I issues, or there are specific F9 issues.

Apart from the NASA F9 demos, no new customers have come on board in the last year.  The DoD IDIQ contract has not produced any new launches, except for possibly this last DARPA test.

The SpaceDev slip of one quarter is interesting in that SpaceX has no Q4 activities, and its unlikely that the Falcon I delays percolated into late 2008; either something affected the SpaceDev payload or there are business reasons for the delay.

 

[spacedreams]

aero313 - 28/3/2007 11:05 AM

bad_astra - 28/3/2007 1:32 PM China has quite literally blown up that paradigm. It may take some time to adjust but I suspect SOME satellites are about to get a lot smaller and a lot cheaper to replace.

Doubt it. The satellites that might be of concern have aparture sizes that are limited by physics - you CAN'T make the antenna or optics package smaller. Yes, you can build a smaller sat with limited capability for a rapid but degraded replacement, and you can also think about smaller sats in a defensive role. In the latter case, the small sat would almost certainly be co-launched with the primary. Also, let's just say that some organizations are looking at what it would take to get bigger satellites launched responsively - although the problem still remains that 24 hr vs. 24 day launch responsiveness is irrelevant if the satellite still takes months in orbit for checkout, deployment, and calibration. AFRL is finally looking at ways to solve THAT part of the problem.

 

Not to mention that the bigger satellites are more likely to be at GEO which makes it a bit more difficult to reach/target for any hostile actions 

[aero313]

Danderman - 28/3/2007  2:21 PM

The satellite contractor will typically ensure that their propellant tanks can hold as much as the selected launch vehicle can handle plus margin. This margin, however, must cover such issues as variance from optimal launch windows, and even to some degree, launch vehicle injection accuracy. So, when does the 100 kg satellite customer know when that margin is available?

There is a reason why most successful commercial GEO comsat launch vehicles do not accommodate secondary payloads.

While I agree that a payload obviously needs to account for margins in propellant load, total mass, etc, I would argue that the real reason that GTO missions do not have many secondary payloads is that GTO is a pretty useless orbit for most smallsats.  You typically have a very low perigee; coupled with a GEO-altitude apogee it means the satellite will come screaming through at perigee, resulting in high drag and a short in-orbit lifetime.  Couple this with two passes through the Van Allen belts on every orbit, a low inclination that puts the satellite out of sight of most ground stations at perigee (not to mention a very short pass duration due to the high perigee velocity) and a very long comm link for a low power, small antenna spacecraft at apogee and you begin to see why smallsats aren't rushing to fly on GTO missions.

Smallsat missions tend to fall into three categories:  observation, which requires a low circular orbit and usually wants to be sun-sync; comm, which prefers a low to mid circular orbit but with variable inclination requirements; and tech demo, which really doesn't care about the orbit so long as the builder's ground station can see the satellite for a reasonable amount of time.  GTO really doesn't satisfy any of these missions.

[Orbiter Obvious]

How important is SpaceX in breaking up the monopoly on the massive companies like Lockheed and Boeing for launch contracts? Could they force those big players to reduce their prices?

[vt_hokie]

aero313 - 28/3/2007  5:31 PM

While I agree that a payload obviously needs to account for margins in propellant load, total mass, etc, I would argue that the real reason that GTO missions do not have many secondary payloads is that GTO is a pretty useless orbit for most smallsats.  You typically have a very low perigee; coupled with a GEO-altitude apogee it means the satellite will come screaming through at perigee, resulting in high drag and a short in-orbit lifetime.  Couple this with two passes through the Van Allen belts on every orbit, a low inclination that puts the satellite out of sight of most ground stations at perigee (not to mention a very short pass duration due to the high perigee velocity) and a very long comm link for a low power, small antenna spacecraft at apogee and you begin to see why smallsats aren't rushing to fly on GTO missions.

Hmm, I hadn't considered the Van Allen belt radiation exposure.  Makes me wonder how they could have possibly saved Orion 3 (there was talk of a space shuttle rescue flight sometime in 1999 I think).  I'm not sure what Orion 3's perigee was/is (I guess it would have been lowered for the shuttle rendezvous), but would that mission have really been feasible?  I'd be curious to know how the satellite was operated while it was still alive and a rescue was being discussed.

[Jim]

Orbiter Obvious - 28/3/2007  9:23 PM

How important is SpaceX in breaking up the monopoly on the massive companies like Lockheed and Boeing for launch contracts? Could they force those big players to reduce their prices?

There isn't Lockheed and Boeing, it is one company ULA.  Not until spacex has something in the same class, then there is no threat

Just like if I built a go cart, would GM and Ford worry?

 

[Jim]

vt_hokie - 28/3/2007  9:25 PM
Hmm, I hadn't considered the Van Allen belt radiation exposure.  Makes me wonder how they could have possibly saved Orion 3 (there was talk of a space shuttle rescue flight sometime in 1999 I think).  I'm not sure what Orion 3's perigee was/is (I guess it would have been lowered for the shuttle rendezvous), but would that mission have really been feasible?  I'd be curious to know how the satellite was operated while it was still alive and a rescue was being discussed.

No rescue was considered

[vt_hokie]

Jim - 28/3/2007  9:27 PM

No rescue was considered

I'm sure I remember reading about it at the time.  

Lest you think I'm crazy...I knew I wasn't imagining things!  

http://www.space.com/news/spaceagencies/orion_satellite_rescue.000526.html

Perigee was very low apparently!  And apogee was lower than I'd have guessed as well.

[kevin-rf]

aero313 - 28/3/2007  4:31 PM
 You typically have a very low perigee; coupled with a GEO-altitude apogee it means the satellite will come screaming through at perigee, resulting in high drag and a short in-orbit lifetime.  Couple this with two passes through the Van Allen belts on every orbit, a low inclination that puts the satellite out of sight of most ground stations at perigee (not to mention a very short pass duration due to the high perigee velocity) and a very long comm link for a low power, small antenna spacecraft at apogee and you begin to see why smallsats aren't rushing to fly on GTO missions.

Unless the test objective of your small sat. is to space qualify your rad hard electronics in the Van Allen Belts. But I am dragging us off topic even further...

[Jim]

vt_hokie - 28/3/2007  9:33 PM

Jim - 28/3/2007  9:27 PM

No rescue was considered

I'm sure I remember reading about it at the time.  

Lest you think I'm crazy...I knew I wasn't imagining things!  

http://www.space.com/news/spaceagencies/orion_satellite_rescue.000526.html

Perigee was very low apparently!  And apogee was lower than I'd have guessed as well.

Maybe a better word would have been seriously considered.  It never got past the back of an envelope

[Avron]

Danderman - 28/3/2007  10:51 AM

Avron - 27/3/2007  9:06 PM    Yip, it starts with a trickle, not very noticable at first, then it grows, feeding on success.. who knows, SpaceX is not limited by anything yet, and they have not gone to the Public for funding.. imagine what they could do with a few $100 million more?

The COTS program is providing Elon with up to $274 million in public funding.

This flight was not part of COTS was it? If not, when will we see what $274 million can do?

[Jim]

Avron - 29/3/2007  12:30 AM

Danderman - 28/3/2007  10:51 AM

Avron - 27/3/2007  9:06 PM    Yip, it starts with a trickle, not very noticable at first, then it grows, feeding on success.. who knows, SpaceX is not limited by anything yet, and they have not gone to the Public for funding.. imagine what they could do with a few $100 million more?

The COTS program is providing Elon with up to $274 million in public funding.

This flight was not part of COTS was it? If not, when will we see what $274 million can do?

Not part of COTS,  Falcon 9 is

[aero313]

Avron - 29/3/2007  12:30 AM

This flight was not part of COTS was it? If not, when will we see what $274 million can do?

No, but the thing to remember is that COTS is now carrying a significant portion of the company's overhead costs.  These are not insignificant costs (priced real estate in SoCal lately?).

[Jim]

aero313 - 29/3/2007  9:59 AM

Avron - 29/3/2007  12:30 AM

This flight was not part of COTS was it? If not, when will we see what $274 million can do?

No, but the thing to remember is that COTS is now carrying a significant portion of the company's overhead costs.  These are not insignificant costs (priced real estate in SoCal lately?).

And they need a new factory

[rpspeck]

aero313 wrote ( Posted 28/3/2007 12:19 PM (#124767 - in reply to #124749) )

“Your statement implies that you don't fully appreciate the phenomena of "staging fraction". On a two-stage to orbit vehicle, a pound of Stage 2 weight is one less pound of payload weight - in other words, a 1:1 staging fraction. The first stage is probably in the 8:1 range. If your goal is to offer a launch cost of $1,000/lb (as an example), then you should be willing to spend nearly $1,000 a vehicle (on a recurring basis) to save a pound of Stage 2 weight, but only $125 to save a pound of Stage 1 weight. This staging fraction, coupled with the fact that Stage 1 SHOULD BE primarily dumb tankage, is why Stage 2 should be more expensive.”

I understand both the “staging Fraction” and the power of the ($ Cost/pound saved) = ($/ps) ratio in making tradeoff decisions.  But the danger with any “mantra” or “rule of thumb” is that they make it easy to forget the assumptions.

The limit ($/ps) ratio will be higher for acceptable options in the second stage IF THEY ARE AVAILABLE.  The real world severely limits the mass saving options and is very nonlinear for those which exist.  An extreme, but real example considers a custom integrated circuit to shave one pound from an electronics module.  The cost of such a circuit typically runs $20 Million.  With optimistic 100 unit production this runs $200,000/pound ($/ps) mass saving ratio.  For LEO, this option is rejected.  It doesn’t matter that the “stock” circuit only costs $100, if no more expensive (but still affordable) lower mass alternative exists.  Moreover, even when a continuity of options exists, the incremental cost (for an enhancement) says very little about the total cost and this relationship depends entirely on the shape (and local slope) of the curves.

This reality remains in both the high and low ($/ps) range when one is restricted to QUALIFIED and APPROVED parts and materials.  Scrap iron can’t be considered to reduce the cost of the first stage because the cost of proving that it was an adequate material would exceed the cost of using aircraft aluminum.  Similarly, exotic materials like carbon nanotubes can’t be considered for the second stage until someone has paid to qualify them for aerospace applications.
 
The bulk of the materials in both stages will actually be standard aerospace components and materials, with lower mass premium forms, if available, used in the second stage.  The aluminum sheet might, for example, be purchased with a tight spec, close to the minimum thickness and excluding extra thick batches.  This reality is evidenced in “dry mass fractions” only modestly better in second stages than in first – the 8 times higher ($/ps) limit in the second stages is actually not buying much mass reduction.

The second stage cost per pound could be 8X greater (for equal structural and engine cost - 8X $ per pound * 1/8 mass) but probably isn’t.  The second stage should cost more PER POUND.  It may or may not exceed the total first stage cost – as will be determined by real engineering, not a “rule of thumb”.

[aero313]

rpspeck - 29/3/2007  9:23 PM
I understand both the “staging Fraction” and the power of the ($ Cost/pound saved) = ($/ps) ratio in making tradeoff decisions.  But the danger with any “mantra” or “rule of thumb” is that they make it easy to forget the assumptions.

The limit ($/ps) ratio will be higher for acceptable options in the second stage IF THEY ARE AVAILABLE....  An extreme, but real example considers a custom integrated circuit to shave one pound from an electronics module.  The cost of such a circuit typically runs $20 Million.  With optimistic 100 unit production this runs $200,000/pound ($/ps) mass saving ratio.

Unfortunately you've confused recurrring and non-recurring cost.  I specifically used recurring cost (and said so) in my very simplistic illustration since that is a real cost that is incurred every time one builds and launches a vehicle.  In the real world the treatment of nonrecurring cost (ie, development cost) can vary greatly.  At one extreme is a fully government funded development program where non-recurring is a paid by the government and no amortization of these costs is necessary in the recurring vehicle cost.  At the other end is a purely commercial venture (say, the development of a new car by GM) where a piece of the development cost is allocated to every production vehicle.  Your IC example is of the latter.   While your example is certainly true in a purely commercial world, we do not live or operate in that world.  At a minimum these sorts of development costs can be tax writeoffs and can be depreciated and recouped over time.  I'm sure Musk is doing this to some extent on his personal investment in SpaceX, so it isn't a dollar-for-dollar cost out of his pocket.  Once one has governement contracts, one can allocate internal R&D costs to labor overhead rates.  This is yet another way for the Gov't to pay for development of a commercial project.   All of these methods (and more) are alternative ways to recoupe a nonrecurring investment that would lower the weight of a vehicle on a recurring basis.

...For LEO, this option is rejected.  It doesn’t matter that the “stock” circuit only costs $100, if no more expensive (but still affordable) lower mass alternative exists.  Moreover, even when a continuity of options exists, the incremental cost (for an enhancement) says very little about the total cost and this relationship depends entirely on the shape (and local slope) of the curves.

This reality remains in both the high and low ($/ps) range when one is restricted to QUALIFIED and APPROVED parts and materials.  ...

In fact there are usually more design options available than the designer has time to properly evaluate, so experience and personal biases usually play in the decision.  As for "QUALIFIED" and "APPROVED"... by whom?  To at least partially drag this thread back on track, the only approval authority for SpaceX (ignoring flight termination hardware) is Elon Musk.  Obviously any hardware the impacts range safety requires that organization's approval, but for mission success issues on a commercial mission, the organization signing the check is the final approval authority.  Qualified is a relative term and again, the organization signing the check gets to define what is qualified and what is not.  MIL-HDBK-1540 is generally accepted as a qual program guideline, but those requirements are not binding on a commercial program.
 

The bulk of the materials in both stages will actually be standard aerospace components and materials, with lower mass premium forms, if available, used in the second stage.  The aluminum sheet might, for example, be purchased with a tight spec, close to the minimum thickness and excluding extra thick batches.  This reality is evidenced in “dry mass fractions” only modestly better in second stages than in first – the 8 times higher ($/ps) limit in the second stages is actually not buying much mass reduction.

Unfortunately, mass fraction is only one optimization metric.  The cost of integration labor is frequently a much greater cost than the cost of the parts.  Also, liquid propulsion systems do not scale very well.  A pump-fed propulsion system might be a perfectly appropriate choice when sized for a first stage, but when scaled to the much smaller second stage the cost per pound for this technology is too great for the weight savings.  Thus, the use of a pressure fed system.  Obviously a pressure fed stage will have a worse tank and plumbing mass fraction than a pump fed system, but when cost is factored in the choice is clear.

The second stage cost per pound could be 8X greater (for equal structural and engine cost - 8X $ per pound * 1/8 mass) but probably isn’t.  The second stage should cost more PER POUND.  It may or may not exceed the total first stage cost – as will be determined by real engineering, not a “rule of thumb”.

No argument here.  I used a gross simplification in my example.  The fact does remain, however, that since avionics are usually located on the top stage, it tends to be the most expensive, particularly as compared to a large stage that is mostly tankage.

[Antares]

Avron - 29/3/2007  12:30 AM
This flight was not part of COTS was it? If not, when will we see what $274 million can do?

Within the next week or two, SpaceX will have gotten $86.4M of the $274M.  They will have met their first 5 milestones.

[Avron]

Antares - 29/3/2007  11:09 PM

Avron - 29/3/2007  12:30 AM
This flight was not part of COTS was it? If not, when will we see what $274 million can do?

Within the next week or two, SpaceX will have gotten $86.4M of the $274M.  They will have met their first 5 milestones.

Thanks for the feedback folks... whats the next milestone, and what is it worth?
A new Factory, says one thing to me, new Business, growth.. that is very positive


( Just to remind us all that SpaceX won that $274 million in the COTS competition, and had to do so with its own efforts... i.e. it won the "business")


Also looks like Elon has been doing some reading here..

So Mr Musk, how do we buy in with SpaceX... ? (money very well invested - when do we get the option?)