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Questions tagged [merlin-1d]

Questions about the SpaceX produced Merlin-1D engine, used by the Falcon rocket.

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What are these flames on the Falcon 9 booster?

When Falcon 9 was on its way to ascend, flames appeared around the bottom of the booster. What are they? It seems to begin around about 20:36 in the video, ...
4
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1answer
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Actuators for gimbaling of engine in rockets and launch vehicles

For controlling the rockets to stay on course, continuous engine control is require which is done by using gimbal actuators. What type of gimbal actuators have been used on SSME, Rocketlab's ...
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0answers
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Why is the exhaust plume of Falcon 9 upper stage shaped the way it is?

The (single) Merlin 1D vacuum engine's exhaust plume has a symmetric shape, comprising of six distinct "inner" plumes. Why does it have this shape? Is it due to the shape/configuration of fuel ...
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1answer
196 views

How do you shut off a Merlin-like rocket engine quickly? How quickly can it be done?

After about 36:17 in part 1 of this recording of SpaceX's Hans Koenigsmann's talk at IAC 2018, he narrates the propulsive landing of a Falcon 9 first stage, and ...
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1answer
626 views

What flame is SpaceX's Hans Koenigsmann describing in his presentation?

At 35:46 in part 1 of this recording of SpaceX's Hans Koenigsmann's talk at IAC 2018, he says something like: The green stuff that you see is TEA-TEB, that’s the ...
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0answers
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Why is Rocketlabs having lengthy combustion chamber?

Looking at different rocket engines, L/D(CC_length/CC_diameter) ratio of combustion chamber is very much less compared to Rocket labs. Even the modern age engines like Merlin 1d and Raptor engines ...
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1answer
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1answer
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What is the Kerosene/LOX mixture ratio of the Block 5 Falcon 9?

as the title would suggest, does anyone know a calculation or solution to finding the current mixture ratio used on the latest block 5 configuration? This would be easier if so many people did not ...
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2answers
539 views

Does anyone know how to calculate the KG per second of RP-1 and LOX from the 9 Merlin 1D engines?

as can be seen from the title, I have been through at least 1,000 chrome tabs in the last few hours trying to find some form of definitive answer, but I've found absolutely nothing. Could anyone help ...
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1answer
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Merlin 1D Engine [closed]

How does the Merlin engine work? How does it's working compare to the working of SuperDraco engine? To be more specific, What features of Merlin make it unique and more efficient than other rocket ...
6
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1answer
622 views

How did SpaceX achieve such a high Thrust to Weight ratio with the Merlin engine?

Were there specific breakthroughs which allowed SpaceX to get such an incredible thrust to weight ratio? The next closest American engine was almost twice as heavy (199 vs 82), and the next closest ...
8
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1answer
1k views

Why does Merlin 1D Vac turbopump drive exhaust go around the nozzle?

In Merlin 1D Vac engine: the turbopump drive exhaust goes around the nozzle. Why is that so? The feature also seems to be missing in the first stage engine, as seen here: (screenshot taken from ...
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1answer
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What is this jet of material spraying out from Stage 2 during the SPACE-X PAZ mission?

This spray seemed to be there throughout the entirety of the Stage 2 burn but was especially visible once Stage 2 cutoff had happened. As that nozzle uses radiant cooling, it can't be cooling fluid, ...
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3answers
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SpaceX merlin engine failure

On SpaceX's website, they make a claim that their rockets are the safest and most reliable in the industry. This is because apparently it can complete its mission even if up-to two of its engines fail ...
3
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1answer
308 views

How do re-usable boosters handle re-entry damage? [duplicate]

Watching Falcon Heavy's side boosters land, I was amazed that they could withstand the stresses of re-entry yet still fire again for a (relatively) slow, smooth landing. I see there are heat shields ...
9
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1answer
2k views

Pintle Injector Face Shut Off - Merlin

The information and schematic are from the web site Pintle Injector Blog. A pintle injector is a variable area injector consists of a movable pintle, an annular nozzle and the central pintle nozzle....
5
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1answer
692 views

Merlin Engine Stoichiometry

As evidenced by the bright exhaust plume at launch, the billowing black smoke rolling out of the flame trench during static tests, the wispy grey effluent from the Merlin Vacuum engine, and the layer ...
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0answers
1k views

Where is the TEA-TEB stored for the Merlin engines onboard Falcon 9?

The Merlin 1D engines can restart up to four times, they use the pyrophoric mixture of TEA-TEB (Triethylaluminum-Triethylborane) to ignite the engines. My question is where is this stored in the ...
6
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1answer
450 views

What does SpaceX do with all the engines?

SpaceX has had 8 successful launches in 2016 according to a wikipedia article. The launch manifest agrees with that, but leaves out the launch pad failure. According to another wikipedia article, ...
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1answer
389 views

What are the differences between the SpaceX Merlin 1D and 1D+ engines?

I am trying to model the Merlin 1D+ using inventor. I was wondering what the major differences between the Merlin 1D and 1D+ were. I find when I search trying to find a 1D+ engine all I come across is ...
6
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1answer
2k views

What material is the Merlin 1D made from?

I am working on high school presentation about rocket engine materials and I'd like to have a part about Merlin 1D engine as it is supposed to be reusable, but I can't find anything about materials ...
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3answers
1k views

GSLV MK2 vs Falcon 9 - Reasons for Huge performance difference

Yesterday ISRO operated the GSLV MK2 launch vehicle, which is a medium lift launch vehicle with a capability to lift 5 tonnes to LEO. I just compared Falcon 9 with GSLV MK2. Falcon 9 capability to ...
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2answers
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Can Falcon 9 first stage landing final burn using one, two, and three engines? Tradeoffs?

This question is about the final burn in the landing sequence of the Falcon 9 first stage return to Earth tests. If I understand correctly, there is usually far more thrust than there is weight at ...
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1answer
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If it is difficult for Merlin engine to have deeper throttling, could it be as an option a different engine at the center of the rocket?

In the landing procedure for the first stage of the Falcon 9 one concern is that : Merlin 1D throttling at its lowest level still generates more thrust than the empty mass of the first stage. So ...
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0answers
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How long does it take to chill the LOX and RP1 for Falcon 9 V1.1 Full Thrust?

The new version of the Falcon 9 v1.1 Full Thrust, or as SpaceX would like everyone to start calling it "Falcon 9", uses super cooled LOX and RP1 to improve the density of the fuel for better ...
7
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1answer
681 views

How many engine firings can a SpaceX Falcon handle?

For every Falcon 9 launch to date, the process has been: Each Merlin is test fired/acceptance fired at McGregor by themselves. The entire stage is test fired at McGregor. The entire stage is hot ...
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7answers
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How can a 9-engine Falcon rocket be cheaper than single engine rockets?

From what I understand, the engine is usually the most expensive part of each rocket, excluding payload. I'm struggling to understand how SpaceX can have one of the cheapest launchers on the market ...
11
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1answer
4k views

How do the Falcon 9 engines re-ignite?

Do they use a tungsten wires or something else?
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0answers
485 views

Falcon 9 v1.1 Full Thrust Specifications

Does anyone know what the dry mass and mass ratio of the Falcon 9v1.1 Full Thrust Stage 1 is? The best info I've been able to find was by taking the specified burn time and multiplying it by the mass ...
5
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1answer
505 views

Falcon 9 engine ignition sequence

On the space shuttle, engine ignition was delayed for the main engines. Not all of them were started at once, presumably to avoid vibrations. How does that work for the Falcon 9? I imagine that the ...
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5answers
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What are the challenges in Falcon 9 “full thrust” (v1.2) with densified propellant?

SpaceX has announced an upgrade to their Falcon 9 rocket, achieving greater thrusts with, as far as I can tell, the same rocket motors (at least, they apparently still call the motors "Merlin 1D"). ...
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2answers
376 views

SuperDraco Dragon V2 vs Merlin 1D Falcon

I figured out that ten SuperDraco engines have about the same thrust as a Merlin 1D. So if we replace Falcon 9's second stage with a Dragon V2 with 2 additional SuperDracos ( and replace some seats ...
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0answers
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What upgrades does the Merlin 1D need to increase its time between overhauls to 1000 hours?

This is a question I've been pondering for the last few weeks after I back-calculated the details of the Merlin 1D engine. Just as a thought exercise, I wanted to see what upgrades the Merlin 1D would ...
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1answer
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What is the cycle life of the Merlin 1D?

I was doing some back of the envelope calculations to see improvements SpaceX would have to make to reach a cost target of $100/kg into orbit. After doing some basic calculations, it seems that SpaceX ...
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3answers
3k views

How does SpaceX plan to achieve reusability of the Falcon 9 *second* stage?

Update 08 April 2017: Elon Musk tweeted an indication that they're revisiting the possibility of second stage recovery, so this question is again relevant, and the details of the new solution may be ...
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3answers
12k views

What are the differences between a standard Merlin engine and the Merlin Vacuum engine?

I know that there's a difference between SpaceX's Falcon 9 1st stage engines and the 2nd stage engine, since that stage is specifically tuned for vacuum. Wikipedia also says that the Merlin Vacuum ...
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1answer
959 views

How low can the single Merlin engine on the Falcon 9 first stage throttle?

As I understand it, the Merlin 1D engine on the Falcon 9 that is used to land the first stage, is fairly limited in how low it can throttle. This makes landing on the barge more difficult -- a ...
6
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1answer
3k views

What is changing between the Merlin 1D engine and the uprated Merlin 1D+ engine?

SpaceX is apparently uprating the thrust of the Merlin 1D engine used on the Falcon 9, by about 15-20%. What are they changing (in the engine, in the fuel) to achieve this new thrust level? It has ...
2
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1answer
1k views

What are the costs of the various different engines in current use?

This may be impossible to answer, since the data is often not disclosed. But in an article, about ULA getting RD-180's from Russia it claims: Each engine reportedly costs between \$11 to \$15 ...
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2answers
490 views

Why does $I_\text{sp}$ on an upper stage matter so dramatically?

When you compare the upper stage of an Atlas 5/Delta 4, which use an RL-10 upper stage engine vs a Falcon 9 upper stage that uses a Merlin 1D Vac version, you see really big performance differences. ...
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3answers
3k views

When SpaceX claims to build 4 engines/week, which engines do they mean?

In this Tweet (dated 11 Sept 2013) Peter de Selding reported that Gwynne Shotwell of SpaceX said: SpaceX's Shotwell: We're building 7 Falcon 9 fairings/yr now, 15 in 2014, & 4 engines/week ...