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Hence the interest recently expressed for reflown cores. That would be a change from the original plan, with the main motivation accelerated schedule.
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... or iPhone users who can't get enough SpaceX

There's an iPhone app which allows you to land a Falcon rocket onto a barge - right in your own swimming pool:

https://www.theverge.com/tldr/2017/6/26/15876374/spacex-arkit-falcon-9-landing-apple-iphone

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Gimballed self levelling platforms are totally standard OTS equipment. That's how fishing boats can pick up Sky TV.

Then again, fishing boats usually rock slowly in the waves and their antennas don't have to cope with plume impingement from a rocket engine and resulting thrashing and vibrations at tens to hundreds of Hz frequency...

No wait, you did not understand. The barge would have a non- or loosely directional antenna to transmit to a nerby boat, and that would have a satellite link. However, there is probably a simple explanation they are not doing it, and it is NOT that they cannot engineer one.

That explanation is that is not important enough a priority. They will have full quality video at multiple angles from the recordings. Telemetry tells them if the stage landed intact in near real time. There is no operational reason why they need perfect realtime video. Even for us spectators it adds to the drama if it cuts off briefly, and we anticipate the recordings like kids on Christmas Eve. Great fun!
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Now it appears the vibration loads will be much more concentrated somewhere near the middle. Would that be a routine engineering calculation, or something they may be risking?

 It's going to make me nervous there won't be a connecting rod across the middle. I'm guessing that might have been a subject of debate earlier in the development process.
Structural analysis is pretty routine by rocket science standards.   Back in the 1960s, NASA saw a bunch of companies each developing their own analysis software, and supported the development of NASTRAN, which has been used and enhanced for more than a half century. 

Unlike combustion analysis or computational aerodynamics, analysis of modes of vibration is a pretty mature field.  Of course you can still make mistakes, but of all the reasons the FH might fail, lack of connecting rods in the middle of stack is pretty low on the list.
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NASA's TDRS-M satellite arrives at Space Coast Regional Airport in Titusville, Florida, aboard a U.S. Air Force transport aircraft.
<snip>
The aircraft in the image is a C-17.

According to TDRS-M satellite and its Atlas 5 rocket shipped to Florida for launch campaign, delivery was last Friday, June 23, from Boeing’s Satellite Development Center in El Segundo, California, via Los Angeles International Airport.

Also,
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[T]he ocean-going Delta Mariner cargo ship delivered the Atlas 5’s booster stage and Centaur upper stage to Port Canaveral today [June 26] after an 8-day journey from ULA’s production factory in Decatur, Alabama.
Were the two stages the sole cargo?

Also,
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The vessel traversed 270 miles up the Tennessee River, 60 miles on the Ohio River and 646 miles down the Mississippi River. The trek then covered 815 miles through the Gulf of Mexico and around to Florida’s east-central coast to the Cape...
Why didn't the Delta Mariner traverse the Tennessee–Tombigbee Waterway?
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SpaceX General Section / Re: SpaceX Falcon Heavy Discussion (Thread 6)
« Last post by CyndyC on 06/27/2017 11:48 PM »
..... back when they thought it would be easy to fasten three Falcon first stages side by side.  Since then much has changed.

Exactly why I came over here, after the grid fin discussion in the Iridium thread, and wondering how tightly the cores could be secured with those [and the legs] inbetween. So a look at http://www.spacex.com/falcon-heavy says and shows bars are connecting the cores only at the top of each first stage and at the bottom near the legs. The Falcon 9 has been flown without that extra stabilization at the top and bottom of the first stage, so the vibration loads have been much more evenly distributed. Now it appears the vibration loads will be much more concentrated somewhere near the middle. Would that be a routine engineering calculation, or something they may be risking?

In contrast to my reasoning last night, there is more counterintuitive reasoning to also consider, related to the fact that brick buildings are less stable in tornadoes and high winds than buildings of more flexible materials, such as wood & vinyl. So maybe the greater risk is where the stages have extra stabilization and less flexibility. Personally I'll be opting for the former consideration. It's going to make me nervous there won't be a connecting rod across the middle. I'm guessing that might have been a subject of debate earlier in the development process.
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Has anyone Modeled a sustainer core with 2-4 over-expanded + 1 standard central merlins?

How and where would those over-expanded Merlins fit?

Take out 2 regular merlins to fit 1 slightly overexpanded one between them. Probably have to kill the center gimbal too.
Yes, or just remove engines 2, 4, 6, 8  and move 1,3,5,7 inboard slightly and add a larger bell
perhaps for the three engine version have two pumps feeding four bells, plus the central standard engine
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One of the best posts this year.
Here is what it all boils down to.

Why?

There has yet to be a good or marginal reason for Spacex to make a RUS for FH.  Nobody has on this forum has yet to come forth with a reason.

FH hasn't flown.  FH has yet to book a payload that needs its whole capability.  So why would they be looking at improvements.

LC-39A is going to be busy with Dragon 2 (cargo and crew), DOD vertical integrated payloads, NASA payloads, FH missions, etc.  So when and how is Spacex going to add a new upper stage that uses a new TEL and still service the existing upper stage.
Your line of reasoning is flawed Jim.

Why is there a Falcon Heavy? There was no need for it given that the heavy payloads could/can be lofted by Delta IV Heavy.

Yet, Falcon Heavy exists.

FH is made by SpaceX. It is to create money to SpaceX, DIVH cannot do that.
The money making machine for SpaceX is Falcon 9, not Falcon Heavy. Haven't you noticed how empty the manifest for FH is and how full it is for F9?
Cannot get why this is so hard for many here to grasp. F9 is "bread and butter". It is an excellent design for exactly what it's supposed to do.

But it is not Atlas-V. Nor any of the other vehicles. IMHO, Musk is pivoting the entire launch service provider business around F9. And "they" collectively ... don't like it. Too bad.

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Falcon Heavy serves only a very limited market. A substantial part of that market will be NSS launches. And frankly, USAF and NRO couldn't care less if FH flies or not. They already have Delta IV Heavy. Having a second heavy lifter at their disposal is merely a "nice to have". You don't believe me? Then explain why USAF never pushed LockMart for Atlas V Heavy. I'll tell you why USAF never did. Because redundancy in heavy lift for NSS is not needed. And that brings us back to my original point. From a standpoint of heavy lifters Falcon Heavy isn't needed. That was the point I was trying to make to Jim: There is no apparent logical reason for FH to exist. Yet SpaceX built it anyway. Which is a clear indicator that SpaceX decision making is not always logical. Something that Jim IMO fails to see.
Agreed.

The biggest benefactor after SX of FH flying 3+ times successfully is likely ULA! Advancing the EOL clock on DIVH likely allows a more nimble ULA. Not because DIVH doesn't ... but because it takes to much, to do it.

FH is a useful luxury. Affordable because of F9 leverage/commonality.

But FH payloads won't be a major increment to SX annual revenue yield, nor net profit. (Not much of a burden either, so by not flying it much won't require as much overhead as other rivals.)

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Why is SpaceX reusing rockets? There was no need for it given that the world did just fine for the past 5+ decades launching on expendable rockets only.

Yet, reusable Falcon exists.
SpaceX is reusing rockets because it makes launches cheaper.
Yeah, that's the SpaceX reason. However, none of the other launch providers ever found it necessary to make their launches cheaper. You wanna know why? Because prior to SpaceX their was no disruptive force acting on the market. The parties in need of launch services gladly paid for the higher priced launches. They had no choice for lack of a disruptive force. And was the point I was making to Jim: Logically speaking there was no reason for reusable launch vehicles. The launch market did not require it. Yet SpaceX went for reusability anyway. So, another fine example of SpaceX making a seemingly illogical decision without a clear why.
Well put.

Space launch has been long overdue for disruption. "They've" fought against it bitterly and are losing that battle.

So "they'll" either have to get good at competing on the edge of the wave of disruption, or fade away.

It has been mostly good our heritage. We shall build upon it, respect it, and take it to the next level as a new heritage.

Disruption means you can get access to business structural problems inside a market. In doing so, you rip it apart, make it work by means that address the structural issue, then put it back together.

To address unserved market that will not accept prior launch service provider offerings, you cannot simply address customers where price is no object. Because those simply raise the cost level when they need something, anything. This is the structural problem.

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Why is SpaceX working on recovering the fairings? There is no need for it given that they are able of meeting their launch schedule even without reusing the fairing.

Yet, fairing recovering is being worked on and tested in practice.

Fairing recovery has nothing to do with launch schedule. It's all about cost.
It is not all about cost. It is about being able to increase the launch cadence. Elon himself pointed out in 2015 that fairing production is labor intensive and takes a lot of time. So much time in fact that fairing production becomes a limiting factor once the launch tempo increases beyond a certain limit. That was, and according to my sources, still is the main driver behind fairing recovery. The improved cost aspect is merely a nice side-effect.
Indeed.

Booster reuse already is speeding up manifest consumption.

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Why is there a SpaceX? There was no need for it given that there were enough launch service providers to cater for the worlds launch needs.

Yet, SpaceX exists.


All of the previous launch providers were too expensive. There was need for cheaper rockets.
Then why is it that prior to Elon having a space-themed brainwave nobody ever bothered to succesfully market a cheaper rocket?
The answer is that there was no need for cheaper rockets. Despite the other launch service providers supposedly being "too expensive" their launch manifests were pretty full. What you don't understand is that launch service providers are interested in reliability first, and cost second. That's why one of the most expensive launch service providers -Arianespace - was capable of catching a full half of the commercial launch market: they were (and still are btw.) the worlds most reliable launch services provider.
Arianespace is also the leader in selling additional launch services to a cautious customer base.

This is the "top of the pyramid" of launch service sales. The most valuable component.

But also the slowest growth rate. The only ones slower are institutional/NSS. Which also have "special needs".

The high growth rate is at the bottom of the pyramid. The business has yet to really reach the level to access it.

And until now, no one has attempting to reach for it. It has been considered "foolish" to do so. Why risk so much for such a difficult opportunity.

Thank you woods170 for saying what needed to be said.
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SpaceX General Section / Re: Raptor Upper Stage consolidated thread
« Last post by docmordrid on 06/27/2017 11:36 PM »
The USAF is planning on DIVH going away by 2023 and choosing a replacement, and only Falcon Heavy, New Glenn, and maybe Vulcan ACES look to be in the hunt.

Add a backup launcher and the notion that the USAF has no interest in FH seems quite unlikely.

http://spacenews.com/delta-4-replacement-ready-by-2023-top-general-says/

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Delta 4 replacement ready by 2023, top general says

Testifying before the House Armed Services Committee’s strategic forces subcommittee, Raymond said that the Air Force expects to have uninterrupted access to heavy launch for national security missions.

Several companies have heavy-lift vehicles in development, including SpaceX’s Falcon Heavy and Blue Origin’s New Glenn, that could replace the Delta 4 Heavy built by United Launch Alliance.

The Air Force has purchased launches on seven more Delta 4 Heavy rockets, Raymond said, though one launch will be a NASA mission. The final launch is scheduled for 2023.
>
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SpaceX General Section / Re: SpaceX Falcon Heavy Discussion (Thread 6)
« Last post by dorkmo on 06/27/2017 11:35 PM »
It is looking like SpaceX will have about a month of downtown between the upcoming Intelsat launch and CRS-12. Is it possible that some of the FH upgrades could be completed during that time?

Id guess they could if they ran three shifts a day.
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