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Dan Adamo, Tuesday, 9-14-14 September 10, 2014

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Dan Adamo, Tuesday, 9-14-14


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Guest:  Dan Adamo.  Topic:  Range safety issues at the proposed Brownsville, Texas spaceport plus much more.  Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, https://thespaceshow.wordpress.com.  Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See http://www.onegiantleapfoundation.org/amazon.htm.  For those listening to archives using live365.com and rating the programs, please email me as to why you assign a specific rating to the show. This will help me bring better programming to the audience.

We welcomed back to the show Dan Adamo to discuss his paper, “Range Safety Implications for Brownsville, Texas Launches To Earth Orbit.”  You can freely download the paper by registering for at http://www.spaceenterpriseinstitute.org.  During the first segment of our 2 hour program, Dan started out telling us why he did the calculations and wrote this paper.  Next and for the balance of the discussion, we talked about range safety issues, the enforcing organization which is the FAA, the Brownsville EIR, SpaceX launches & how they might work given the range safety constraints that may be applied to this launch site.  As you will hear, Brownsville is a completely new launch site with zero history or data behind it so as Dan said, it might have been very easy to overlook or even defer the analysis regarding range safety issues.  Also note that Dan said range safety issues are not concerned with the normal or the nominal ground track.  The range safety rules consider what may go wrong and who might be impacted by a failed launch, even if it might be rare that such an incident would happen.  In response to email questions, Dan said that range safety issues apply to the launch regardless of destination though clearly they can limit the choice of destination as in the case of limitations from Brownsville to the ISS. Dan does a good job of explaining this in the first segment and throughout our discussion. He also addressed listener questions regarding a possible difference in the range safety rules for cargo/satellite launches & human launches.  Another issue that came up questioned if FAA range safety rules would be applicable to a private spaceport in the same way for a government launch center like the Cape, KSC, or Vandenberg.  Dan said yes and explained the reasoning behind range safety rules.  Joe emailed in about range safety for Russian launches, then as the segment ended, our guest addressed launching from other parts of the Texas Gulf Coast which he said presented similar constraints as Brownsville.

In the second segment, Alan asked Dan if he would write a simple primer for orbital dynamics to help the untrained person understand the issues better.  Dan will be considering doing that.  The question came up if SpaceX rockets would be required to use explosives on board for a destruct command or if the termination of thrust in a problem launch could be handled by other means.  Dan got specific questions about the EIR and a possible Falcon Heavy launch as well as Falcon 9 launches.  As we neared the end of the show, the subject of reusability came up and then the sparks flew as listeners did not like what Dan said and which I supported.  For the most part, the controversy arose because Dan suggested that some customers may not want to pay for the launches of others through reusability and in fact may need more lift from the rocket or more fuel on board their satellite.  Reusability requires putting extra mass for hardware and fuel on the rocket, not the customer’s payload.  He noted that several Falcon 9 launches had already been made without the reusable hardware.  I supported this economically & suggested that as we move toward a fully commercial launch market, customers will buy the launch that meets their needs.  Some may be OK with the lower launch costs and less payload capacity while others may need all the fuel they can get on their satellite or all the launch power they can get to put their heavy payload into the right orbit.  I made an analogy to the trucking industry where people rent or buy the type and size of truck they need to get the job done & suggested this would emerge for our launch industry in the future.  Listeners objected, remained focused only on lower launch costs & not customer requirements. Several listeners sent in strongly worded emails of disagreement with Dan and me for our comments.   Both Dan and I said over and over again we supported SpaceX in its reusability work and were glad they were doing this work.  We only suggested that the economic of it were still unknown but that would likely change fair soon given the success SpaceX is having with its R&D for reusability.   Still, this did not set well with some listeners.

If you have questions/comments please post them on TSS blog above.  Even your critical emails but remember our rules for civility.  Ideas are fair game, w e do not permit character assassination or name calling.  If you want to disagree with Dan, do so with civility.  Also, if you do want to disagree, brings facts to the discussion as that is always better than just ideas without supporting information to backup the ideas.  You can email Dan Adamo through me.  Be sure to download his paper and read it.



1. B John - September 16, 2014

Has any attempted rocket launch to orbit, or any sub-orbital ICBM, ever crashed and killed someone on the ground many miles away after having taken off? Is this an important problem, or more of an imaginary worry?

Matt - September 16, 2014

Not many miles, but some miles: In China, in 1996 a long march rocket did kill hundred people in village after 22 seconds of flight.

B John - September 16, 2014

Yeah, some miles… Within 22 seconds, how far would a rocket get from Brownsville? Is that at all relevant to the “range safety” concerns which Dan Adanamo talked about on the spaceshow? Or were you just another one of those which Dr. Space himself complains about “Didn’t listen to what he said!” (in the opening of his following show)?

And I would like to ask you if you have any reliably sources about what really happened in that case in China 18 years ago, but of course no one does and I don’t blame you for that. But how is the imagined scenario of a rocket launched from the new SpaceX facility on a Texas beach in 2016, falling down killing people in Florida far far away, comparable to the 1996 commie government launches in the middle of the most populated country in the world killing people nearby?

Thousands of rockets with orbital payload have been launched. Some by desperate political regimes for war purposes. And still people have not been killed by them crashing down hundreds of miles away? No one? Not in 70 years? So… therefor there is an imagined “safety” reason for the government to refuse SpaceX to use Brownsville? I DON’T THINK SO! And I really hope that Dan Adamo doesn’t actually claim that.

Matt - September 16, 2014

I did only some googling, but here is something about thsi worst accident:


LocalFluff - January 18, 2015

I agree. The entire space industry should be abolished. It is to dangerous.

Dwayne Day - September 18, 2014

“And I really hope that Dan Adamo doesn’t actually claim that.”

Why don’t you bother to actually listen to the show before you fly off the handle?

2. Paul - September 11, 2014

Dan Adamo mentioned that he uses the software of his own design to run trajectory simulations and that it runs on an old

Macintosh operating system. If the hardware gives out, he loses the ability to run the software because it lacks compatibilty with

the new OSes. It seems to me there must be a way to run his software inside one of the Mac OS emulators in Windows, Linux,

or new Mac. There are emulators of various old hardware setups. I think it unlikely he didn’t think of this before, but just in case

he didn’t, I wanted to mention that. Here is one link:


Or possibly use something like VirtualBox.

If that doesn’t work, I think he should describe the problem in a post on slashdot.org; those guys like those kinds of things and

would probably come up with something useful.

3. The Space Show - September 11, 2014

Listeners, Dan sent the following information for me this morning in that he has now made available the primer or orbital and flight dynamics that listener Alan asked about with his email. Here is Dan’s comment and the URL:

“Per my promise to “Alan” during our Brownsville discussion, I’ve posted my “Interplanetary Cruising” primer on the SEI website. Note this download doesn’t have the “Popular” attribute so it doesn’t affect what’s initially seen on the SEI homepage. Just direct your listeners to http://www.spaceenterpriseinstitute.org/2014/09/interplanetary-cruising/ to obtain a copy of this primer.

Listeners, remember you do need to register at the spaceenterpriseinstitute.org website to freely download papers.



4. jimjxr - September 11, 2014

Regarding the 2nd stage safety issue, I wonder if Dan considered the following:
1. There is FTS on 2nd stage, if they trigger that the stage would be in pieces, given its near orbital velocity, wouldn’t most of it be burned up during reentry?
2. SpaceX named their Texas holding company Dogleg Park LLC, so it pretty obvious they are considering doing doglegs, I wonder if this can be taken into consideration.

Regarding reusability, I think there’s some important facts missing from the discussion:
1. FH is vastly overpowered for a normal GTO launch, its full expandable GTO capability is 21 tons, while the heaviest GEO bird is only about 6 tons.
2. F9 has done 4 GEO launches, none of them has reusability hardware or the fuel reserve, but for different reasons. The 1st two launches (SES and Thaicom) are for 3 ton satellites, and they used the reusability performance reserve to put them into SSTO which is better than GTO, based on SpaceX’s statement it looks like this is a bonus given to early customers. For the two Asiasats, there’s no reusability tests since they’re too heavy (4.5 tons), SpaceX has said in the future satellites like these would be launching on FH.

Given these facts, I think we can have a rational discussion regarding reusability economics:
1. The reusability penalty: Reusability would reduce the payload you put into orbit, there’s no question about this. But it is only a penalty if this payload reduction means you couldn’t lift as much mass as your competitor. This is currently true for F9 when launching heavy GEO birds, so they had to fly expandable some times. But for FH, there is no penalty, since it has so much excess performance, even if reusability eats a lot of it, it still have enough performance to compete with Atlas 5 or Ariane 5. If you look at SpaceX’s website, FH’s price is for 6.4 tons to GTO, this is the performance given all 3 1st stages are reused, and this is comparable to other launch providers’ heavy vehicles, so there is no penalty here.
2. So the economics is pretty easy if we assume reusability works technically: you can launch the same mass to the same orbit, either using a expandable vehicle, or a cheaper reusable vehicle (which is more powerful than the expandable vehicle), seems a no brainer to me.
3. Finally, even if a customer wants all the performance he can get, this doesn’t mean he couldn’t benefit from reusability, since SpaceX can fly a recovered 1st stage in this case, the benefit wouldn’t be as large, but it’s there.

Chufu - September 11, 2014

Thanks, but I think that are not all issues in respect to reuse:

1. In case of FH central stage cannot flown back, it it too fast.

2. Furthermore, a resuable vehicle (or stages) needs to be more reliable and robust, because it shall used many times. It is not clear that standard very light F9 lower stage or FH lower stages have this capability. We do not know, which loads are applied to stages during landing at more windy weather and which could case fatique damage. What about engine life time? Every small deviation from planned landing procedures will cause of vehicle, because it so fragile.

3. Finally, will the user accept used rocket stages? Can he be sure to get stages with same reliability as new one?

jimjxr - September 11, 2014

1. Yes, it can fly back, the 6 tons to GTO number assumes center core flies back. If you expand the center core, FH can lift more than 10 tons to GTO. Remember FH’s full expandable capability to GTO is 21 tons, it has a lot of performance reserve.

2. This would be the technical issue I mentioned, nobody knows for sure at the moment. But we know the F9 1st stage can fly several short flights, F9R-Dev1 proved this. SpaceX also said Merlin 1D can fire 40 duty cycles, so they are not going into this blind.

3. Yes, SpaceX will need to assure customers that reused stage is as reliable as new ones, I think test flights of F9R-Dev2 in New Mexico would help here, they can also demonstrate this in CRS flights.

Chufu - September 12, 2014

O.K., I understand stage reuse for GTO injection relies on a significant scarification of launchers payload capability.

Another point: The stages to be returned are not missiles and may exhibit only a quite low lateral acceleration capability, because they are so thin walled. I am wondering, which aerodynamic angle of attack (AOA) the stage can handle? It may necessary to build up a significant AOA to steer the stage to the targeted landing point during guided and controlled descent. The landing on small target was not yet demonstrated. I think will try to use a beacon to support the navigation and guidance for the case that barge (if a barge landing is objected) moves in the sea. In this case SpaceX needs also a stabilized platform on barge to compensate for pitching, yawing and rolling due to sea.

5. Max - September 10, 2014

I am not finally convinced that first stage of Falcon is able to “hit” such a small area as a barge of potential 1000 m² in ocean as discussed in show.

We saw also at the last stage landing trial that the stage came down apparently some miles away where the observing aircraft had it awaited and the stage displayed finally a quite large angle of inclination to the vertical of 10-20°. Some work to do.

Some simple calculations using rocket equation and Falcon 9 data predict a loss of at least 35-40% of payload if fly-back to launch place is attempted (only by used propellant for breaking, return acceleration and final landing).

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