SpaceX Successfully Delivers AsiaSat-6 to Orbit in Spectacular Sunday Morning Launch

SpaceX has successfully lofted its fifth Falcon 9 v1.1 mission of 2014, and its seventh flight of the upgraded booster in less than 12 months. Photo Credit: John Studwell/AmericaSpace
SpaceX has successfully lofted its fifth Falcon 9 v1.1 mission of 2014, and its seventh flight of the upgraded booster in less than 12 months. Photo Credit: John Studwell/AmericaSpace

In spite of ominous weather conditions at Cape Canaveral Air Force Station, Fla., which required a slight, 10-minute adjustment of the targeted T-0 launch time, SpaceX has successfully executed its fifth Falcon 9 v1.1 mission of 2014. Liftoff of the two-stage vehicle, carrying the AsiaSat-6 telecommunications satellite into geostationary transfer orbit, took place at precisely 1:00 a.m. EDT Sunday, 7 September, from Space Launch Complex (SLC)-40 at the Cape, turning night into day across the Florida landscape. This year is shaping up to be a banner 12 months for SpaceX, marking the first time in its history that it has launched more than three missions and gradually cementing the reliability credentials of Elon Musk’s Hawthorne, Calif.-based launch services organization.

As described in AmericaSpace’s AsiaSat-6 preview article, the mission was originally targeted to fly on 26 August, but was initially postponed by 24 hours, following the explosion of the Falcon 9 Reusable Development Vehicle (F9R Dev) on 22 August and the need for SpaceX engineers “to review the circumstances that caused the test vehicle to auto-terminate to confirm that there is not a risk to orbital flight.” Rescheduled for 27 August, the second effort to get AsiaSat-6 airborne was called off about 10 hours before the opening of the launch window and the mission was delayed by up to two weeks, reportedly to allow additional verifications of “the Falcon 9 fault detection and recovery logic, with particular focus on highly improbable corner-case failure scenarios.”

At length, the 45th Weather Squadron revealed Thursday, 4 September, that a launch attempt would be made on Sunday, 7 September, and this was subsequently confirmed by both SpaceX and AsiaSat on Friday afternoon. With a 70 percent likelihood of acceptable meteorological conditions—and key concerns centering upon the possibility of violating the Thick Cloud Rule—the launch was scheduled to occur during an expansive “window,” extending from 12:50 a.m. until 4:04 a.m. EDT.

Powered by nine Merlin-1D engines, the Falcon 9 v1.1 turned night into day across the Cape. Photo Credit: Alan Walters/AmericaSpace
Powered by nine Merlin-1D engines, the Falcon 9 v1.1 turned night into day across the Cape. Photo Credit: Alan Walters/AmericaSpace

Shortly after 8:40 p.m. EDT Saturday, SpaceX management kicked off the lengthy process of loading liquid oxygen and a highly refined form of rocket-grade kerosene (known as “RP-1”) into the propellant tanks of the Falcon 9 v1.1, in order to feed its nine Merlin-1D first stage engines. The cryogenic nature of the oxygen—whose liquid state exists within a temperature range from -221.54 degrees Celsius (-368.77 degrees Fahrenheit) to -182.96 degrees Celsius (-297.33 degrees Fahrenheit)—required the engines’ fuel lines to be chilled down, in order to avoid thermally shocking and fracturing them. Within an hour, by 9:35 p.m. EDT, all propellants were fully loaded aboard the vehicle.

As expected, the Thick Cloud Rule reared its ugly head, with the Eastern Range declaring itself “Red” (“No Go”) at 10:50 p.m. However, with conditions expected to revert to “Green” as temperatures cooled following a stormy day at the Cape, SpaceX slightly adjusted its T-0 time to 1:00 a.m. EDT Sunday. The standard Go-No Go poll of all stations at T-13 minutes took place promptly at 12:47 a.m., producing a flurry of rapid-fire “Go” calls across the board, and this set up the countdown for its “terminal” phase at T-10 minutes. During this phase, the Merlin-1D engines were chilled, ready for their ignition sequence, and at 12:53 a.m. AsiaSat-6 was transferred to internal power, and the rocket itself transitioned to its on-board batteries. All external power utilities from the Ground Support Equipment (GSE) were disconnected, and at 12:55 a.m. the approximately 90-second process of retracting the “strongback” away from the vehicle got underway. The Flight Termination System (FTS)—tasked with destroying the Falcon 9 v1.1 in the event of a major accident during ascent—was placed onto internal power and armed.

By T-2 minutes and 15 seconds, the first stage tanks had reached flight pressure. “Range Green!” came the call from SpaceX’s Range Operations Co-ordinator (ROC), clearing the weather as the last remaining issue in an otherwise flawless countdown. The Merlin-1D engines were purged with gaseous nitrogen, and, at T-60 seconds, SLC-40’s “Niagara” deluge system of 53 nozzles was activated, flooding the pad surface and flame trench with 30,000 gallons (113,500 liters) of water, per minute, to suppress acoustic waves radiating from the engine exhausts. At T-3 seconds, the nine Merlin-1D engines roared to life, ramping up to a combined thrust of 1.3 million pounds (590,000 kg). Following computer-commanded health checks, at the stroke of 1:00 a.m. the Falcon 9 v1.1 was released from SLC-40 to commence SpaceX’s fifth mission of 2014, turning night into day across the Cape.

Immediately after clearing the SLC-40 tower, the rocket executed a combined pitch, roll, and yaw program maneuver to establish itself onto the proper flight azimuth to inject AsiaSat-6 into geostationary transfer orbit. Eighty seconds into the ascent, the vehicle surpassed the speed of sound and experienced a period of maximum aerodynamic stress (colloquially known as “Max Q”) upon its airframe. At about the same time, the Merlin-1D Vacuum engine of the second stage underwent its own chill-down protocol, ahead of its own ignition later in the ascent phase. At 1:02 a.m., 130 seconds after liftoff, two of the first-stage engines throttled back, under computer command, in order to reduce the rate of acceleration at the point of Main Engine Cutoff (MECO).

Beautiful view of the effect of the Falcon 9 v1.1's exhaust upon high-altitude clouds. Photo Credit: Alan Walters/AmericaSpace
Beautiful view of the effect of the Falcon 9 v1.1’s exhaust upon high-altitude clouds. Photo Credit: Alan Walters/AmericaSpace

Finally, at 1:02:41 a.m., the seven remaining first-stage engines were shut down and the lower component of the Falcon 9 v1.1 separated from the rapidly ascending stack. The turn then came for the restartable second stage, whose single Merlin-1D Vacuum engine—with a maximum thrust of 180,000 pounds (81,600 kg)—roared to life at 1:02:49 a.m. to continue the boost to deliver AsiaSat-6 into orbit. Thirty seconds into its burn, the 43-foot-tall (13.1-meter) payload fairing was jettisoned, exposing the satellite to the space environment for the first time. Finally, the Merlin-1D Vacuum shut down at 1:09:35 a.m., after which the stack coasted for 17 minutes, prior to a restart at 1:26 a.m. The second burn lasted approximately one minute and served to raise the orbital apogee to geostationary altitude. AsiaSat-6 was released into free flight a few minutes later at 1:32 a.m.

Built by Space Systems/Loral (SS/L), the cube-shaped satellite weighs 8,100 pounds (3,700 kg) and represents one of the largest and most powerful AsiaSats ever inserted into orbit. Following initial checkout, AsiaSat-6 will be positioned at 120 degrees East longitude. It will be operated by the Asia Satellite Telecommunications Company Ltd., headquartered in Hong Kong, and 14 of its 28 high-powered C-band transponders will be leased to Thaicom—under a $171 million, 15-year contract, signed in December 2011—who will market them as “Thaicom-7.” The satellite is equipped with one “global” beam and one “regional” beam, providing region-wide coverage of Asia, Australasia, Central Asia, and the Pacific Islands, with enhanced power and look angles over Pacific Rim countries.

AsiaSat selected SS/L in November 2011 to build its AsiaSat-8 and AsiaSat-6 platforms, both of which are expected to support 15-year operational lifetimes. Based upon the LS-1300 “bus,” with a pair of deployable solar arrays and batteries, both satellites breezed through thermal vacuum tests last December and underwent dynamic tests and Compact Antenna Test Range (CATR) tests in January-February 2014. The latter allowed engineers to measure antenna and payload performance and demonstrate their compliance with spacecraft specifications. “These critical tests are essential,” AsiaSat reported in December 2013, “in order to achieve the highest quality and reliability of the spacecraft before shipment to the SpaceX launch pad at Cape Canaveral.”

The Falcon 9 v1.1 takes flight from Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station, Fla. Photo Credit: Alan Walters/AmericaSpace
The Falcon 9 v1.1 takes flight from Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station, Fla. Photo Credit: Alan Walters/AmericaSpace

The arrival of AsiaSat-6 marks the tenth in a series of satellites, which can trace its ancestry back almost a quarter-century. AsiaSat-1, launched atop a Chinese Long March-3 booster in April 1990, had an interesting back story, for it was originally the Westar VI communications satellite, delivered into an improper orbit by shuttle mission 41B in February 1984 and triumphantly retrieved and returned to Earth by the 51A shuttle crew the following November. AsiaSat-2 followed in November 1995, also aboard a Long March rocket, after which the third (AsiaSat-3) and fourth (AsiaSat-3S) satellites in the series were delivered by Russian Proton-K boosters in December 1997 and March 1999. The latter replaced the decomissioned AsiaSat-1 from May 1999 and is today the oldest member of the fleet still in operational status. Kicking off the 21st century, AsiaSat-4 rode an Atlas IIIB from Cape Canaveral in April 2003, followed by AsiaSat-5 atop a Proton-M/Briz-M from Baikonur in August 2009, AsiaSat-7 in November 2011, and AsiaSat-8 in August 2014.

Stunning "streak" effect, with high-level clouds illuminated, during first-stage flight. Photo Credit: John Studwell/AmericaSpace
Stunning “streak” effect, with high-level clouds illuminated, during first-stage flight. Photo Credit: John Studwell/AmericaSpace

AsiaSat-5 entered the headlines in the summer of 2014, during the World Cup coverage from Brazil, when it delivered the first-ever live telecast of the international football competition in 4K resolution. Commonly (though not strictly accurately) known to the general consumer as “ultra-high-definition television” (UHDTV), 4K produces horizontal resolution of close to 4,000 pixels, more than four times higher than standard HDTV and capable of 60 frames per second. AsiaSat-5 delivered live 4K coverage of the Colombia-Uruguay Round of 16 match on 28 June, followed by the Germany-France quarter-final on 4 July and the final, between Germany and Argentina, on 13 July. According to AsiaSat, the worldwide number of 4K television households is expected to rise from 2.2 million at the end of 2013 to as high as 66.2 million by the end of 2018. Moreover, the Asia-Pacific region is forecasted to become the single largest 4K television market by 2016, accounting for 42 percent of global 4K television households.

As with its sibling, AsiaSat-8, launched on 5 August, the geostationary requirement of the AsiaSat-6 mission required the maximum performance capability of the Falcon 9 v1.1 and consequently the booster was not equipped with extendible landing legs and did not perform a “propulsive return-over-water” and controlled splashdown. The next attempt to perform such a maneuver will be made during the launch of the fourth dedicated Dragon cargo mission (SpX-4) to the International Space Station (ISS), which was originally scheduled for launch on 19 September, but which may suffer some slippage in the wake of the AsiaSat-6 delays.

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    • Or just get the competition to up the ante. SpaceX is doing well, But depending on a single supplier of anything is a bad idea.

        • I think history will render a verdict on single suppliers there as well. I think it is unfortunate that lawsuits are necessary as a means of communication in that instance. In many fields a block buy of 40 units would be a normal way to reduce costs. The current snafu is an artifact of there being only one realistic supplier (ULA)for a period of time.

          Actually my meaning should have been stated that limited suppliers for any good or service tends to drive price up and quality down. Boeing and Airbus having no effective competition on airliners limit the choices for instance.

  1. Great news now SpaceX must land on an ocean barge for the CRS4 to contest Blue Orgin patent filing for the same ….

    • Hi Tracy,

      I am not a lawyer, but I believe SpaceX has to win its patent contest with Blur Origin to legally use the barge approach.

      Additionally, CRS-4 will supposedly launch on September 19 (about 11 days from now).

      – Where is the barge (have they built or bought and modified one)?
      – have they trained recovery crews to do what would be a very exacting job?

      • Joe,
        I don’t think SpaceX has to do as you are indicating above to demonstrate intent of ability when you consider they have already completed two “soft water” landings with the 1st stage booster. By putting a barge in the ocean and then making a stated attempt to land on it shows continuous progressive capability whether or not the actual landing was achieved.

        When a patent is filed the company does have to demonstrate the ability to perform the action or provide the service or create the object etc. At this juncture I think Blue Origin will have a harder time completing their patent process in regard to showing these capabilities vs SpaceX.

        • Tracy,

          As I said I am not a lawyer, but from the news accounts I have read (link to one below) Blue Origin already has a patent and SpaceX is trying to take it back.

          I am now going to stay out of any further discussion of patent law; perhaps another reader with a legal background can shed light on the subject.

          On the subject of an attempted barge landing on CRS-4, they would need a barge, modified to be a rocket landing pad (whatever that would entail). CRS-4 is supposedly going to launch in 11 days and as far as I know there is currently no such barge. If you (or anyone else) knows of such a barge please provide information. Otherwise 11 days is a very short time to produce one.

          • Joe,
            I did read the article and….the comments below the article which seem to prove my point that it is highly unlikely that Blue Orgins’ patent will stand. Furthermore I was mistaken as the response from SpaceX gives evidence of three other groups suggesting the very same thing. Hence there is no need for SpaceX to put a barge out in the Ocean to contest anything rather it would appear they already have contested it as the article suggests this is “common knowledge”..

            • Tracy,

              I went to the article and read the comments.

              As an engineering grad student at U. Texas—Austin, I audited two IP law classes. In my business career I have been through three tort cases and directly and indirectly in two IP cases. So I know a bit more than the common person but far, far less than an IP attorney, and zip compared to the Blue Origin IP attorneys.

              But I do know enough to say with 99.99999% confidence that none of the commenters are an attorney. Therefore, their opinion on whether Blue Origin will prevail in defending its patent has only marginally more weight than a Mongolian horse herder’s living in the remotest of steppes and without connectivity. Some of the reasons given as to why BO would fail were obviously ignorant of what obviousness is and isn’t, what constitutes prior art, and none seemed aware that a big part of any patent exam is the petitioner’s due diligence and documented development, their R&D if you will.

              Both SpaceX and Blue Origin have a large number of good attorneys. But Blue Origin, because Bezos’ net worth is over twice that of Musk’s, has the advantage of more money, more lawyers, and therefore more time. As to the outcome of this fight, we will all have to wait several years to know that as it goes from trial to the appellate.

              Lastly, if you are interested in the back-and-forth of this patent fight, I’d suggest adopting a law review covering this case as your source, rather than SpaceRef, for less GIGO.

              • Hi Jim,

                In Tracy’s defense I am the “guilty party” for the Space Ref link. It was one of several general news articles I had seen and the easiest to find.

                As I said I am not a lawyer, but all the articles seemed to indicate that SpaceX was trying to overturn a patent Blue Origin already had.

                Since you have had some experience with this kind of thing a question:

                You say it may well take years for the issue to be resolved. Assuming SpaceX can technically accomplish the “barge landing”; can they attempt it legally until the issue has been resolved?

                • Good question. The whole purpose of a patent is to give an inventor a temporary monopoly in order to profit from their innovation, absent any exceptions due to other factors, e.g. FRAND licensing. So, if SpaceX goes through with that barge landing without injunctive relief, it had better win its case to invalidate the Blue Origin patents. Deliberate and willful infringement is looked upon very poorly, re Samsung. As I recall, and it has been awhile, there might be mandatory penalties in that situation.

                  • Do patents apply to commercial operations, or do they completely prevent any research in the area? Surely it will be quite some time before the landings will be followed by commercial re-launches.

              • Jim,
                Clearly you and I disagree on validity or importance of BO ocean barge landing patent…I don’t believe that BO patent will prevent SpaceX from landing on an ocean barge. Time will tell if this patent holds up. Musk has been adamant not to patent his systems because he believed that China would simply copy his designs.
                Perhaps he was naïve to think that others would NOT feel the same way about patenting as a way of trying to slow SpaceX progress.

                Musk has always indicated the future of his company will be completely determined by a reusealble rocket system … I am puzzeled why considering the success that SpaceX has had thus far that they didn’t plan on a ocean barge at the start of this testing…Which I do think is only for testing as his ultimate objective of launch, land, refuel and launch again within 24 hours will require landing back at the launch site…

                • Tracy,

                  Blue Origin has also been working on re-useable rockets from the very beginning. In fact Dr. Bill Gaubatz (the head of the Delta Clipper Project) was working for them as a consultant up until his untimely death earlier this year. A number of other former Delta Clipper personnel also work for Blue Origin. Therefore, your assertion that the patent was achieved as a way to “slow SpaceX progress” is without merit or factual basis.

                  It is illustrative, however, of SpaceX fans growing enemies list.

                  (1) Originally it only included what they referred to (when they were feeling polite) as the “Shuttle Mafia” which included by extension Constellation Systems and now SLS/Orion. ULA was considered an ally and only good things were said about the Evolved Expendable Launch Vehicle (EELV).

                  (2) Next ULA became an enemy and the EELV became the Extremely Expensive Launch Vehicle, as the SLS is the Senate Launch System (a level of juvenile snark sure to impress an 8 year old).

                  (3)Now Blue Origin becomes an enemy. It does not matter that it is a “new” space company, perhaps the only one that can honestly claim to be commercial, as they are not taking government money. All that is required is that they may stand between Musk and anything he wants.

                  • Joe,
                    Clearly SpaceX and Blue Orgin and ULA are all competitors for future space services in one fashion or another. And whether or not this was the intent when the government started this process is unknown. Currently SpaceX is the only company that I see that offers any hope as to truly reduce launch costs with their reusable plans which they have publically presented to some extent..I realize that there are others and I look forward to what BO is doing as well as Serria and Excor and others who have not been named…Additionally while SLS is not part of that “reuseable” group I do expect LM to dust off the X-33 at some point and fast track a reusable production craft as well. I think the market will be big enough for all of these players…I hope SpaceX does NOT get the NASA crew ship contract as I want them to strictly serve the commercial market that will allow them to continue to innovate unhampered from to much government red tape..

                    • Tracy,

                      Noble sentiments and I applaud you for them.

                      I would hope that in the future you could support those sentiments without finding it necessary to baselessly question the motives of others whose only crime is to be in an altercation with SpaceX. An altercation initiated by Musk.

                    • Tracy,

                      Since you follow SpaceX very closely, concerning reusability of hardware, how many Dragons have been reused so far? When will that change? If you know, please tell us. The company’s business model was built on the promise of reusability and not reusing Dragon’s has to be impacting the bottom line, although to what extend I hardly know.


                    • Jim,
                      I don’t believe any Dragons have been reused and I didn’t think any would be until SpaceX completed Dragon V2 Cargo which has the landing legs and retro rockets installed…I don’t think there was a plan to reuse anything that went into the Ocean…As for when… I think that after the booster is finalized for reuse (1 to 2 years my guess) then the Dragon V2 Cargo would be next followed by the 2nd stage

                • Tracy,

                  I am not in a position to put any merit as to the validity or importance of the Blue Origin barge rocket landing patents. To do so requires at least a law degree or a good deal of experience in IP matters, neither of which I have.

                  But here’s what I think. I doubt Bezos or BO hired anything but very good IP lawyers and I imagine they feel pretty good about their work. And Musk, seems to have a “Ready, shoot, aim!” approach to matters of law and hasn’t exactly had a good run in the courts–I think he’s 0-2 or nearly so. So, if I was a betting man, and forced to make a call on this, I’d go with Blue Origin. But heck, every dog eventually has its day, and maybe Musk will to in a court.

                  Why didn’t SpaceX consider a barge in the first place? Well, if you go back to 2013 and Musk’s Press Club dog-and-pony show, you can see that SpaceX was planning on landing at KSC. I guess he was finally convinced that wasn’t going to happen. So, barge. Also, a barge a few hundred miles off the cost means that much less fuel that needs to be spent reversing the velocity of the Falcon first-stage. I’ve heard that a reusable Falcon 9 first stage costs 40% of payload mass, so any savings on the mass budget would be good. Also a barge means that if something goes awry, people are less likely to die.

                  • Jim,
                    I think that the thing about Patents and Lawyers in space right now is that less is more and I don’t think the government that has really tried to limit red tape and over regulation in this new industry is going to allow to many patents or Lawyers to mess this up…NASA has been shackled by launch cost issues going back …forever. The Shuttle was supposed to be the cure all..Then the X-33 and VentureStar…etc.

                    Yes I do believe that Musk makes this up as he goes…That is his genius…. That and doing very very simple things simplify those even further and computerize them…

                    Now I have heard on this board with great interest on the fuel cost for the “retrograde” turn required to launch in one direction and bring the booster back in a 180 degree direction will be impossible to achieve… I feel pretty certain that SpaceX will find a solution to that as well whether that means putting retractable wings on the booster or completing a single orbit like the planned 2nd stage or combination of the two or as you say he has come to the conclusion of a ocean barge..Or does he land in the Caribbean?

                    • Tracy,

                      Do not want to beat this too much, but the old adage “There ain’t no such thing as a free lunch” applies here.

                      Anything that adds weight to the first stage (or alternatively causes it to use less fuel during ascent) will reduce payload. The question is, how much?

                      Your inventive solution to the problem (retractable wings) would add weight and complexity.

                      Jim noted in an earlier discussion that SpaceX originally intended to recover the stage down range using parachutes, but decided that the chutes weighed too much. How they decided that the fly back scenario would be lighter would make for an interesting story.

                      If they could make a complete orbit (like the second stage) they would not need a second stage, but they obviously do.

                      The barge solution is certainly more practical, but remember that re-usability is not an end in itself, it is desirable only if it reduces cost.

                      A few things to contemplate:
                      – You would then have additional constraint: weather at the landing site.
                      – How is the stage to be returned to the launch site (barge returns to shore or use another water going vessel? Land vehicles from dock to launch site?)?
                      – How does this additional handling affect Musk’s assertions that the stages will be turned around in one day with no required refurbishment.
                      – Musk also assert they will be flying 100’s of times/year (if not 1,000’s of times/year) how big a fleet of these specialized barges would be required to support such launch rates.

                      How much operational cost would be added by all that extra activity.

                    • Joe,
                      Can SpaceX land at Bermuda? Or doe the “normal” trajectory take the craft further north to say into Georgia? As for retractable wings, wouldn’t the reduced weight of the fuel loss and payload loss mean that a lightweight wing for gliding be somewhat feasible to create some lifting ability? Certainly the DOD or NASA has experimented with something like this I would think…Serria’s Dream Chaser isn’t that directly from the H-20 Lifting body X craft from the Air Force or something?

                    • I’ll chime-in here. I went to Bermuda as a teenager and my answer is, “No”. It’s too crowded for one. It’s chock-full of people. Bermuda real estate is pricey, the inverse of Brownsville, TX real estate. Crashing into that would be very, very expensive.

                      Once you add wings, the structural dynamics, and thus the structure of the stage, change a lot.

                    • Tracy,

                      The Administration, and by extension NASA, have no say in whether an aerospace company can get a patent.

                      As for flying back a Falcon 9.1 first-stage, the fuel cost is 30-40% of payload mass, according to SpaceX engineers.

                      But let’s walk through an intro into astrodynamics; first stage fuel mass that would have other-wise been used to increase the velocity of the rocket to get the payload into orbit is instead needed stop or even reverse it’s motion, depending upon when this happens in its trajectory, and then provide for a soft landing. This fuel unused for delivery of payload is a fuel mass penalty.

                      The delta-v needed to get into orbit is roughly 17,000 mph, or 7,600 m/s. The velocity component due to the earth’s rotation is 914 mph, or 410.1 m/s. So a rocket needs to add 16,086 mph, about 7,190 m/s. The ideal rocket equation is a good back-of-the-envelope to figure out very roughly how much fuel you’ll need for a given mass, ignoring the penalty due to total drag and staging, among other factors. Initial mass, mi, is the mass of the whole rocket, that is fuel, engines, structure, and payload. Final mass, mf, is all of that less the fuel. If you think about this, you can immediately see the beauty of staging. Tsiolkovsky was cool. Anyway, g is whatever you using for gravity, either 32.2 ft./ s^3 or 9.81 m/s^3. And Isp is the specific impulse, performance or efficiency really, of your propulsion system. The units are s^-1, but everyone just uses “seconds”. For SpaceX’s Merlin 1D engines, Isp is at between 282 to 311 s^-1, or averaging 297 s^-1. So, with all of that, here Tsiolkovsky’s equation,

                      delta-v = g Isp ln( mi / mf )

                      You know already that Dragon can get a 10 mt payload (or whatever it is) into LEO. Once Elon tells us how much fuel is roughly needed to accomplish the fly-back, you can deduct that from the mass ratio and punch that into the above eqn. and get a rough idea for yourself of the payload mass penalty the fly-back costs. Easy-peasy.

                      I need to stress that Elon’s whims and desires have zero effect on astrodynamics. Astrodynamics is fair in that all are equally penalized.

                    • Jim,
                      Thank you for a very detailed explanation of launch formulas that are common knowledge among the rocket engineers…Which begs the question…. Is Musk just wrong in his stated plan of landing the booster back at the launch pad? Does this prove he intended to land at sea all along? Or is there more “math” that you didn’t list that allows Musk to think he can still complete launch pad landing? Why would he intentionally lie?

                    • Jim,

                      Excellent explanation of the basics.


                      – Is Musk just wrong in his stated plan of landing the booster back at the launch pad?

                      – Does this prove he intended to land at sea all along?

                      – Why would he intentionally lie?

                      Those are all interesting questions, to which many people would like the answers. Unfortunately, per Mike Killian’s post below, we are not likely to get any answers from SpaceX.

                  • Jim and Joe,
                    Clearly you both come from the aerospace industry…What does Musk do if can’t land back at the launch PAD? John below has an idea about a hovercraft that has a 50 ton capacity that enough to put some type of “booster catching crane”??? What say you ???

                    • Tracy,

                      Just a personal opinion.

                      As much as I am fascinated by John’s concept (even if it did not turn out to be operationally practical, it would be impressive to pull it off once), SpaceX needs to consider concentrating on making the Falcon 9 a reliable expendable vehicle.

                      Jim may have more information on this, but I saw presentations at the beginning of the COTS program where SpaceX intended to use parachutes to recover the first stage for the purpose of studying it to be able to increase reliability while decreasing manufacturing cost. There was mention of possibly re-using some components (if it was economically justified), but that was a secondary objective.

                      The goal was to eventually provide a relatively low cost expendable vehicle, reliable enough to be considered crew rated and try to achieve a flight rate of as many as 50 flights/year. That (in my opinion) was an ambitious but potentially achievable goal and (believe it or not) I was very enthusiastic about it.

                      Somehow that morphed into the current situation.

      • Hi Joe,

        You always have good questions about SpaceX. However, by now it should be pretty obvious SpaceX will tell us all, media & public alike, only what they want us to know. As a commercial company that is understandable, but will take some getting used to (we’re all used to NASA having to make stuff freely & openly available). Bottom line, many questions will likely never be answered, it’s moreso just wait & see…

        • Hi Mike,

          I understand what you are saying and hope my questions are not irritating to you.

          I keep asking them because people (based to a considerable degree on statements by Musk) believe that all kinds of unlikely things are “just about to happen”.

          A barge landing on CRS-4 is a good example. If such a barge does not exist by now, it is not going to be produced from scratch by the end of the year; and a barge being modified in a ship yard would be a hard thing for even SpaceX to keep secret.

          • Not at all, your questions are always appreciated. I meant it moreso as just something that is becoming more of a reality, getting used to not getting all the facts, or whole story, with SpaceX, because of them being a commercial company rather than the NASA America has been used to for 50 years.

  2. @ Jim 12:54 AM

    Minor quibble with one number. I believe the 7,600 m/s to reach orbital velocity has already taken Earth rotational velocity into account for an actual orbital velocity of 8,000 m/s.

    I think we can agree that boost back is very expensive in terms of payload hit to orbit. For every 1,000 m/s that an empty stage must use to boost back and land, about 400 m/s could have been added to the upper stage velocity for the main task. (If I have my guestimates right for the various Falcon masses) That 400 m/s unit subtracts about 12-15% of final mass of an upper stage, which all comes out of payload. Multiplied by however many 1,000 m/s units are needed to get the first stage home can lead to very high payload hits.

    As an inventor myself, I have a couple of observations on the patent issue. It is very difficult to write a patent that is so comprehensive that it prevents people from designing around it. For instance an air cushion vehicle may not be covered. Some very large air cushion ferries were retired some time ago from the English channel run that might have the capability if still available and modified. Design around by this or another method is likely to be more effective that fighting the patents directly.

    • John,

      I am no expert on “air cushion” vehicles (hover craft?), so believe me I am not arguing with you.

      If there really are such vehicles big enough (and stable enough) to allow an F9 first stage to land on it and remain stable long enough for a recovery crew to check for toxic fumes (from the hypergolic attitude control system) and strap it down, I really (no sarcasm intended) want to see that done. Even if it is not practical as a routine procedure, it would be impressive.

      • Joe This was example it would take some research to reach the level of being an idea. My info is from a couple of documentaries on the ferries and marine corp lcac. iPhone at lunch more later

        • Joe,

          Sorry about the earlier reply. IPhones are hard to use for comments when you are a geezer with limited tech skills and time limited.

          I did a quick search. Marine LCACs are listed as 60-75 ton payload capacity with a speed of over 40 knots. The channel ferries had a capacity of 52 cars and a speed of 60 mph.

          Dim memory from somewhere way back is that air cushion vehicles are more stable than an equivalent sized ship. That is a dim memory and not reliable. I may do a bit more looking on this aspect.

          If it looks feasible enough for a blog post, I may write it up as an actual idea at

          • John,
            Thanks for your contribution. I see these things happening with SpaceX and as a laymen am puzzled as to “why” SpaceX has accomplished so much in so little time …..Which I suppose really just means this rocket technology is very mature to the point of being ripe. I am very interested in what they are up to next and how they innovate or adjust their plans …but seem to keep moving forward…So thanks for giving me at least an idea on how they might get around a barge patent for ocean landing. And if the Hover craft can travel at 60MPH then if the are out to sea 200 to 300 miles then it is merely a day trip to return to land and also with the hover craft can’t it just drive right up onto land and right next the processing building for booster off load.??

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