jump to navigation

Open Lines, Sunday, 6-28-15 June 29, 2015

Posted by The Space Show in Uncategorized.
Tags: , , , , , , , , , , , , , , , ,
trackback

Open Lines, Sunday, 6-28-15

http://archived.thespaceshow.com/shows/2498-BWB-2015-06-28.mp3

Your Amazon Purchases Helps Support TSS/OGLF (see www.onegiantleapfoundation.org/amazon.htm)

If you rate shows on live365.com, email me your rating reasons to help improve the show

Guests: Open Lines with Dr. David Livingston; Topics: Falcon 9 launch failure, SpaceX, New Horizons, Pluto, and 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.

 

Welcome to our last Open Lines program for June 2015.  During the first segment of our 2 hour 9 minute program, we started off with my customary suggestion of a few topics including the Falcon 9 launch failure and a Space Review article from June 8 of this year by Dr. Sam Dinkin, “How much money would it take to launch enterprise into space? (See www.thespacereviewe.com/article/2766/1).  Our first caller, Dr. Dwayne Day, wanted to talk about Sam’s article and analysis.  We had an interesting discussion on its contents but see what you think after reading the short article.  Dwayne also talked about the coming Pluto flyby by New Horizons.  I then asked Dwayne for his thoughts on the Falcon 9 launch failure.  Dwayne offered us several interesting observations about the launch failure and SpaceX.  Our next caller was Tim from Huntsville and he too wanted to talk about the Falcon 9 launch attempt.  He kept repeating we have to do better than chemical rockets.  Before the break, I read an email that came in from Kelly.  Kelly is not a fan or supporter of SpaceX but as you know, The Space Show is willing to air all sides of an argument so I read Kelly’s email on air as it had much to say that was critical about SpaceX.

 

In the second segment Kelly was our first caller.  I put it to Kelly to support his critical comments about the company.  Kelly then talked about lots of issues about SpaceX processes ranging from parts, manufacturing, cutting corners, safety and more.  Several listeners sent in emails asking Kelly direct questions about what he was saying.  I made it clear that I did not agree with much of what he was saying but you give it some thought and decide the issue for yourself. Keep in mind that it is not unusual for a new rocket to have problems, even to fail to reach orbit.  Sometimes many flights have to take place to discover a problem. As I said, I have every confidence that SpaceX will fix whatever the problem is and resume launches as soon as possible.   Kelly sent in a few additional emails during the balance of the show to support the claims he was making.  Our next caller was Dr. Doug from S. California. Doug wanted to talk about the Falcon 9 launch and the need for multiple launchers which he said were a good thing.   Listner Karen emailed us with a question about the Falcon 9 debris field, then Tim called back, then Michael Listner called to continue talking about New Horizons and Pluto.  During Michael’s call, he got a listener question asking if the money would have been better spent on a Uranus mission.  He also talked about the possible regulatory impact of the Falcon 9 loss including RD180 engines, ULA, Air Force certification, and fallout with Senator McCain on his subcommittee regarding the RD180 engines.   Dwayne called back to talk Pluto, the Decadal Survey and planetary missions, plus he talked about the Applied Physics Lab (APL), the Uranus mission mentioned earlier by a listeners and more.

 

Please post your comments/questions on The Space Show blog above.  You can reach all the callers and emailers through me.

Comments»

1. J Fincannon - June 29, 2015

Tim was wanting something better than chemical rockets. Space elevators are not the solution for reliability simply because they can be severed by orbital debris or meteorites. Any kind of “gun launchers” have much larger g loads than humans or typical satellites can endure, besides heat loads or sonic booms on launch. Scramjets are just another advanced aircraft that can have launch failures. The only options that might be safer are low velocity ones like JPAerospace’s.

Matt - June 29, 2015

What about beaming? No, to be serious, there are several problems with present launcher technology: It needs an oxidizer onboard (makes even the major mass fraction), which makes it principally hazardous in combination with the fuel. The low Isp of chemical rockets allows only about 6-8% mass fraction of launch mass itself. There are no reserves for such a thin-can design in context with “bad handling” and overloads. A further problem is that there are practical no performance reserves to account for significant, not awaited disturbances during ascent. However, the most important disadvantage in terms of mission safety is that conventional chemical launchers ride alone on its thrust. No or less thrust equals vehicle loss.

Therefore, is for the far future, the best concept for transportation to LEO in terms of safety: 1. Use of wings and horizontal launch and landing 2. Separation of energy and propellant by help of fusion process 3. Use of an inert propellant as water for fusion rocket. 4. Most important: Increase of allowed structural mass fraction from 8 to 50% to allow a very robust design, which allows to some degree large overloads not expected, made possible by fusion propulsion.

Matt - June 29, 2015

Correction: “… allows only about 6-8% structural mass fraction of launch mass itself. “

Kelly Starks - June 29, 2015

Really the mass fraction isn’t the big issue. Things like some form of jet engine system to get you to Mach 6-7 halves your take off weight of LOx and Fuel.

Really though the issue is just economies of scale. You need to spend nearly as much as a long range aircraft of the same cargo capacity – but just fly a few flights over the service life of the fleet. Bad partof the economic curve.

Space Elevators (besides just being impossible to do) make it much much worse with vastly higher capital costs.

Matt - June 30, 2015

Hello Kelly, my very futuristic scenario from above will be S/F for a long time, even if Dr. Bussard made some first proposals. I sketched it, because I would like to demonstrate what characteristics an ideal launcher could me. Imagine, a winged launcher, which has large weight margins, which allow to install additional turbojets for the initial part of flight (even this could use the fusion drive) and water for an active cooling of the metallic TPS, which has “unlimited” usage time. Huge performance reserves. For the design of the airframe and propulsion system much safety factors can be applied (not 1.2 or 1.5 instead 2 or 2.5 so). All this will be possible, if one times a fusion driven rocket propulsion system with an Isp of 4,000- to 5,000 seconds and high power to weight ratio is available.

Kelly Starks - June 30, 2015

I’ve done some work looking into whats possible with the fusion electric drives Bussard worked up. (I can post AIAA paper names etc if interests.) Using water as a reaction mass, you can get 3,000-4,000 isp, and if you build a very large engine (possibly 100 foot across reactor core) you could get a thrust to weight over 10. Given that with big heavy ships – you could probably get lift in the dollars per ton range. With chemical your at $10-$20 a pound to orbit at best with current tech WITH A HUGE MARKET! 9Most space advocates credit to much to technology, and nothing to basic economics.

In deep space where you can just use the straight plasma diluted for more thrust but lower ISP, or not for max iSP you can get ISP hundreds of thousands to perhaps a million. [Have to look up my notes.]

Between the two fusion drives and some heavy and rugged ships, you could profitably mines oil andiron from the inner solar systems objects.😉

Matt - June 30, 2015

Please post the fusion rocket AIAA paper here, thank you.

One point is finally not clear to me. Is the space payload market as elastic as assumed? Or otherwise said, it is sure that at very low specific launch cost (which results from this market explosion) really a market explosion will happen? Maybe it is not only a launch cost issue, but also an issue of very harsh space environment, which affects every space related utilization of resources and makes it costly. Or is there also a way to make it much cheaper by a not mass-driven design?

Kelly Starks - July 6, 2015

Sorry I haven’t see this sooner:
AIAA (and other) papers on Bussard fusion propulsion.

System Technical and Economic features of QED-Engine Driven Space Transportation” 33rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference, July 6-9, 1997 Seattle WA.

AIAA 94-3269 From SSTO to Saturn’s Moons: Super performance Fusion Propulsion for Practical Spaceflight By Robert W. Bussard and Lorin W. Jameson

“Inertial-Electrostatic-Fusion Propulsion Spectrum: Air-Breathing to Interstellar Flight”, R. W. Bussard and L. W. Jameson, Journal of Propulsion and Power, v. 11, no. 2, pps 365-372.

“Aneutronic Fusion Propulsion for Earth-to-Orbit and Beyond” by H.D. Froning, Jr.,Flight Unlimited, 5450 Country Club, Flagstaff, AZ 86004 and Robert W. Bussard, Energy/Matter Conversion Corporation, 680 Garcia Street, Santa Fe, NM 87505

Bussard, R. W.; DeLauer, R.D. (1958). “Nuclear Rocket Propulsion”. McGraw-Hill.

Bussard, Robert. “Nuclear Rocketry – The First Bright Hopes”, Astronautics, Vol. 7, No. 12, Dec. 1962, pp. 32-35

Bussard, R.W.; DeLauer, R. D. (1965). “Fundamentals of Nuclear Flight”. McGraw-Hill.
R.W.Bussard, “Fusion as Electric Propulsion”, “Journal of Propulsion and Power” v6 no 5 September–October 1990, pp 567-574

The Advent of Clean Nuclear Fusion: Super-performance Space Power and Propulsion, Robert W. Bussard, Ph. D., 57th International Astronautical Congress, October 2–6, 2006.

Bussard R.W., “The QED Engine System: Direct-Electric Fusion-Powered Rocket Propulsion Systems“, Ppr #263, Proc. 10th Symp. Space/Nucl Pwr and Propln, Alb. NM, 14 Jan 1993

Bussard R.W. and Jameson L.W., “The QED Engine Spectrum: Fusion-Electric Propulsion for Air-Breathing to Interstellar Flight“, AIAA ppr 93-2006, 29th Joint Prop. Conf., Monterey, CA 6/28-30/93; in JPP, v11, n2, pp.
365/372.

Bussard, R.W. and Jameson L.W., “The QED Engine Spectrum: Fusion-Electric Propulsion for Cis-Oort/Quasi-Interstellar Flight“, Proc. 44th Cong. Intl. Astronautical Federation, 10/22/93, Graz, Austria

Kelly Starks - July 6, 2015

> One point is finally not clear to me. Is the space
> payload market as elastic as assumed?
> Or otherwise said, it is sure that at very low
> specific launch cost (which results from this
> market explosion) really a market explosion
> will happen?

There have been various studies suggesting it. Busnesses in the 80’s were interested in big projects using the shuttle — but they didnt trust NASA.

The current, even decades past, technology can IF THE OPERATIONAL SCALE IS BIG ENOUGH, can generate cost per pound to orbit can be lowered down bellow $20 a pound. But at the current scale of only a couple dozen of flights a year, and under a 100 tons a year, globally. Not a prayer.

>..Or is there also a way to make it much cheaper
> by a not mass-driven design?

By ‘81in a study done by NASA in late ’81, referencing these three designs, was expecting much lower cost to orbit numbers then folks of the time expected.
“…The workshop decided that, although rather advanced technology and well developed operational management would be required, it was proper to target the average cost of gross cargo payloads into LEO at $30 (1979)/kg for construction of the initial SPS. The further cost goal for repetitive construction of 30 to 60 SPS would need to be reduced to $15 (1979)/ kg for all operational payloads for ESLEO and would require the use of advanced, long-lived vehicles with a sophisticated operational organization, ..” .
“..an evolutionary series of heavy-lift and personnel-launch vehicles with chemical rocket propulsion can be targeted realistically to move heavy masses into LEO for $30(1979)/kg by the year 2000. More advanced propulsion technology and vehicles may make $15(1979)kg a goal in the foreseeable future. ..”

page-138 & page-248 NASA Technical Memorandum 58238 “Satellite Power System: Concept Development and Evaluation Program Volume VI1 -Space Transportation” Nov ‘81

B John - June 29, 2015

I don’t see the problem with chemical launchers. With reusability they would only consume natural gas, the cheapest form of energy on Earth. It doesn’t sound like a great idea to invest a thousand billion during a hundred years to develop fusion launchers, just in order to try to price compete with the products already available on the 50 cent shelf at Walmart.

Matt - June 29, 2015

I questioning the commercial success of present reusability approach. I predict SpaceX will fail with it, may be even technically.

I did not see why methane shall make such a big difference to kerosene in price. The propellant cost will play only an important role if real reusability is achieved and many, many flights happen.

BTW, SpaceX’s recent failure (and all the others seen in last 60 years) demonstrated the principal problems with chemical rockets. There are no margins, all is quizzed out to maximal extent and therefore sensitive. In this case, the extreme thin walled LOX tank saw probably an “over-pressurization” due to a valve fail function or a bulkhead failure. If weight does not matter, you can build the whole system much more robust, include more margins and makes it less sensitive. It is a difference if you can build the launcher’s structural mass 5-8-times more heavy.
We will probably never see a launcher based on chemical rocket propulsion, which is able to achieve reliability of a commercial airliner. Up to now, present chemical launchers has achieved only values between 95 and 99%. Those are very low values for a transport system and are contributed to the very nature of launchers based on chemical rockets, which are explosive devices, where its explosive components are not finally mixed yet. Even if reuse is successful technical wise, it is open if the reliability will decrease or increase with every flight of reused vehicle in my view.

B John - June 30, 2015

VTOL eliminates some of the “no margin” problems. You don’t need to have a nice fly down to a particular runway, you could land in the forest, ocean or on someones back yard in an emergency, just like any parachutist (or hang gliders, a wonderful thing to test! At least once…) does in an emergency. And ULA’s Vulcan concept looks even better to me than SpaceX concept does, given that it works.

Falcon 9 v1.1 seems to weigh 506 tons at launch, compared with 333 tons for v1.0 (I see Wikipedia). They certainly have invested alot of mass into extra fuel and extra sturdiness and landing gear. The first stage going straight on for a few seconds while its first stage/payload disintegrated during the CRS-7 failure, is pretty impressive.

I’m not sure that SpaceX can reuse their soft landed launchers. But anyway the path to reusability in different shapes is now underway, driven by multiple players. And it will reduce launch costs downwards to the fuel cost. That will change our lives, next decade already. Won’t bring people to Mars soon (what drug is Elon on?), but “skynet” in the form of internet everywhere always and stuff like that is already happening.

Matt - June 30, 2015

My futuristic talk about fusion driven rockets is something what may happen in 200-300 years or so (if mankind has survived until this date). Meanwhile, we are stick to the chemical launchers and have to optimize it.

I like the idea of a large and robust launcher, which is launched from sea and splash-down there again. Similar to the “Sea dragon” concept from Robert Truax, but somewhat smaller. A rocket builds in a ship-yard not in aerospace industry. His pressure-fed design was so large and robust that no parachute was necessary to recover both stages from flight, both splashed down into ocean with a velocity of a few hundred km/h (if I remind correct), without being damaged. Space’s landing stages are egg-shell-like devices filled gases, which can explode as displayed. There are destroyed by the smallest deviation from nominal landing.

Kelly Starks - June 30, 2015

>..I did not see why methane shall make such a big
> difference to kerosene in price. The propellant cost
> will play only an important role if real reusability
> is achieved and many, many flights happen.

Eaither way, the better packability of Kerosene would be a big plus for a launcher. And Kerosene cost is quite manageable.

> BTW, SpaceX’s recent failure (and all the others
> seen in last 60 years) demonstrated the principal
> problems with chemical rockets. There are no margins, …

That really isn’t the issue. Its just space craft in general (and SpaceX specifically) doesn’t do anything like the level of quality assurance and testing normal to aircraft etc. Especially with expendables, test flights are hellishly expensive – and the craft normally turn themselves into scrap, its hard to detect non dramatic failures.

Though another factor for SpaceX is the Falcon is a expendable design they are trying to band aid into a partial reusable. Really a hard expensive way to do it. Wich really hurts any effort to get relyability up.

Matt - June 30, 2015

In this context: It may be difficult for SpaceX to come to final conclusion about failure’s cause without any debris.

Kelly Starks - June 30, 2015

>..doesn’t sound like a great idea to invest a thousand
> billion during a hundred years to develop fusion launchers, …

more like tens of billions, over years, rather then trillions over a century. 😉

The basic reactors are looking for a couple hundred million to test them out.

J Fincannon - June 30, 2015

I have worked on the beam launchers before. Very interesting. The very small ones launched with ground based lasers use the air provided by the atmosphere to move.
https://en.wikipedia.org/wiki/Lightcraft
It did have some concerns, mainly needing to spin very fast and you needed to point pretty big lasers into space which might have some hazards to objects outbound. I recall being surprised how little energy the lasers needed. I think you needed alot of them though. The separate design of larger vehicles using microwave beamed power had to carry their own fuel and it seemed like alot of power to me.
This report outlines the results of the NASA/DARPA study:
http://ntrs.nasa.gov/search.jsp?R=20120002761
I do not see launching people with these vehicles. I also do not see them being “safer” or more reliable than chemical rockets. They may be less expensive if the infrastructure can be developed and life space of ground hardware is reasonable. For the small laser launchers, loss of a single vehicle would not be a big deal, its selling point is being able to launch lots of small vehicles. But it has a limited size.

I think there are obvious concepts to make chemical launch vehicles safer and more reliable, but these are always at the expense of upmass and cost. The same reason we do not have parachutes on commercial airplanes ( or even dedicated chutes on private airplanes). If we want to make the launch vehicle _impervious_ to a mission failure due to launch vehicle failure, you need costly heavy designs. It can be done, but no one is ever willing to do it.

JPAerospace’s concept seems to have more potential than fusion launchers.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: