Talk:Falcon 9 Block 5

Successor
What will be the successor of Falcon 9? — Preceding unsigned comment added by 84.61.230.52 (talk) 21:43, 6 May 2017 (UTC)


 * Falcon 9 will be complemented by Falcon Heavy for heavier payloads, but long-term it and FH will be replaced entirely by the BFR according to Elon Musk's presentation at the 2017 International Astronautical Congress. TROPtastic (talk) 06:55, 18 December 2017 (UTC)

Merger proposal
I propose that this page be merged into the corresponding section in the Falcon 9 article. As a version of the Falcon 9 rocket it seems more appropriate to have a slightly larger section within the original article instead of an entirely separate article just for Block 5, especially considering that there aren't huge differences between Block 5 and previous versions (as far as we are aware) and that it is seen as an improvement on Falcon 9 (and not a separate rocket) both by SpaceX and by external observers. As far as I know, there isn't really a precedent for having separate articles for variants of other rockets, eg. Atlas V and its many configurations, so it would be odd to start one for Falcon 9 Block 5. It wouldn't take much work to expand the Block 5 section of the Falcon 9 article since much of the information is already there and there is already a comparison table for the other versions of the Falcon 9 rocket. TROPtastic (talk) 06:49, 18 December 2017 (UTC)
 * Support – Block 5 succeeds Block 4 which succeeded Block 3: all these variants implement incremental changes to the rocket; the overall design has remained the same since the v1.2 "Full Thrust" version. The company itself only calls the product "Falcon 9" and downplays the block 3-4-5 evolutions. There were more substantial differences between Falcon 9 v1.0 and v1.1 (much taller, more powerful engines) and with v1.2/Full Thrust (densified propellants, slightly taller still, successful reuse). — JFG talk 11:53, 18 December 2017 (UTC)
 * Note: I would rather merge this into Falcon 9 Full Thrust, which includes blocks 3-4-5, leaving the Falcon 9 article for an overall description of the rocket family. — JFG talk 12:01, 18 December 2017 (UTC)


 * Support - As a minor revision of the Falcon 9 Full Thrust, Block 5 belongs there. Currently there is a lot of interest in Block 5 but I guess that as soon as it flies and SpaceX moves on to other developments this page will be left for dead. Mateus Araújo (talk) 13:11, 18 December 2017 (UTC)
 * Support I agree with an above suggestion about merging with F9 full thrust. YuriGagrin12 (talk) 20:58, 19 December 2017 (UTC)
 * Support - merge into Full Thrust article. The landing legs should be significantly different and the second stage could see notable changes (as SpaceX is considering landing it), but that can be discussed in the FT article. --mfb (talk) 07:07, 26 December 2017 (UTC)
 * Last I heard, recovery of the second stage was off the table; do you have fresh news? — JFG talk 23:53, 28 December 2017 (UTC)
 * Reuse is gone. Did you see a comment that even recovery (to learn more about reentry, or for inspection) is not planned any more? --mfb (talk) 00:08, 29 December 2017 (UTC)

Looks like we have unanimous approval. ✅ — JFG talk 03:43, 29 December 2017 (UTC)

Requested move 12 March 2019

 * The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

Moved as proposed. Consensus is clear. bd2412 T 04:49, 21 March 2019 (UTC)

Falcon 9 Full Thrust Block 5 → Falcon 9 Block 5 – As far as the Falcon 9 and Falcon 9 Full Thrust articles and its sources are concerned, Block 5 is the fifth major version of the Falcon 9 overall, and is the third revision of the Falcon 9 Full Thrust / Falcon 9 v1.2 / Falcon 9 Block 3. The name "Falcon 9 Full Thrust Block 5" implies that it is the fifth version of Falcon 9 Full Thrust and not Falcon 9. In addition, there is no common name argument to be made for the status quo's case whatsoever. I have been unable to find any reliable third party source that describes this variant as "Falcon 9 Full Thrust Block 5" or any similar term. Meanwhile, NASASpaceFlight.com [1 ], The Verge [2 ], Yahoo! News [3 ], and CNBC [4 ] all use "Falcon 9 Block 5", while Space.com [5 ], and Florida Today [6 ] have used "Block 5 Falcon 9", and Ars Technica [7 ] has used "Block 5 variant of its Falcon 9". On Google, an exact phrase search, which is made by book-ending a phrase with quotation marks ("), returns only around 900 results for "Falcon 9 Full Thrust Block 5" [8 ], but around 143 thousand results for "Falcon 9 Block 5" [9 ]. – PhilipTerryGraham (talk &middot;&#32;articles &middot;&#32;reviews) 23:08, 12 March 2019 (UTC)


 * It is the fifth version of Full Thrust. Musk said that a while ago. The first three just never got much attention as individual versions. --mfb (talk) 00:08, 13 March 2019 (UTC)


 * Do you have a source for that? Also, how come both the Falcon 9 and Falcon 9 Full Thrust articles pose it as the fifth version of the Falcon 9 and the third version of the Full Thrust if this is true? The lineage seems to be Falcon 9 v1.0, Falcon 9 v1.1, Falcon 9 Full Thrust, Falcon 9 Block 4, and Falcon 9 Block 5. There seems to be an understanding that the original Full Thrust, a.k.a Falcon 9 v1.2, is Block 3. List of Falcon 9 and Falcon Heavy launches also conforms to this lineage. What are Blocks 1–4 of Full Thrust then, if this lineage is incorrect? There are literally only three versions of Full Thrust and five versions of the Falcon 9 overall. What are these mysterious two other versions? – PhilipTerryGraham (talk &middot;&#32;articles &middot;&#32;reviews) 00:52, 13 March 2019 (UTC)
 * See here, for example. This lead to Musk saying Block 5 should be called Version 7 (link dead). We had a more extensive discussion on one of the older talk pages, you can go through the archives if you want. --mfb (talk) 01:09, 13 March 2019 (UTC)
 * Same discussion at Falcon 9. --mfb (talk) 01:14, 13 March 2019 (UTC)
 * Most of the links featured in these comments are reddit threads and links to Elon Musk's social media pages. Reddit is not a reliable source, as anybody can hop on and claim to be an employee of SpaceX, and it can be argued that Musk's social media pages aren't exactly that reliable of a source either. He once stated on Twitter that "SpaceX will try to bring rocket upper stage back from orbital velocity using a giant party balloon [...] And then land on a bouncy house." [1 ]. I should also remind people of the current drama surrounding Musk's misleading tweets about Tesla [2 ][3 ]. Here are the only third party sources I could find in your links, Mfb:
 * One NASASpaceFlight.com article [4 ] which states "Blocks 1-4 [of the Full Thrust] were slowly implemented in 2016 and 2017", but do not mention what the differences between all alleged four blocks of the Full Thrust are, only describing Falcon 9 booster B1021 as a "Block 2". There are no sources to corroborate this, not even the sources listed on the booster's own Wikipedia page. The article also uses the "Falcon 9 Block 5" name a couple of times, which only further cements the common name argument.
 * Another NASASpaceFlight.com article [5 ] also makes extensive use of the "Falcon 9 Block 5" name, stating that Elon Musk prefers "to call it Falcon 9 2.5 if anything". It does not describe a Block 1, 2, or 3, but mentions a Block 4.
 * An article from "The Climate Report" [6 ] describes "V1.2 Blocks 1-3", but is also just as oblivious as to what the three blocks are, and their differences from one another, deciding to describe the alleged three blocks as one. It also states "At various times in its life, it’s been called Falcon 9 v1.0, Falcon 9 Block 2, Falcon 9 v1.1, Falcon 9 Upgrade, Falcon 9 v1.2, Falcon 9 Block 3, Falcon 9 v1.1 Full Thrust, Enhanced Falcon 9, Full-Performance Falcon 9, Falcon 9 Block 4, Falcon 9 v1.2 Block 4, Falcon 9 New Design Spin, Falcon 9 Block 5, Falcon 9 v1.2 Block 5, and Falcon 9 Version 7." and summarised the alleged Blocks 1–4 of the Full Thrust as "Smooth implementation made this development continuous and ill-defined. That was v1.2 Blocks 1-4." Not exactly confident language here. – PhilipTerryGraham (talk &middot;&#32;articles &middot;&#32;reviews) 02:39, 13 March 2019 (UTC)
 * SpaceX is the most authoritative source we can have for the question how SpaceX numbers their blocks, and Musk is CEO of SpaceX. It shouldn't matter if he writes it on Instagram or Twitter, or mentions in an interview that is reported by a conventional source. Second stage recovery got abandoned after it was considered for a while - how is that relevant here? The lack of information how the first three blocks of Full Thrust differed is not relevant here either. "Falcon 9 Block 5" is indeed a common name and I think moving the article is fine, but it is still the fifth version of Full Thrust. Your claim that it would be the fifth version overall and the third FT version is wrong. --mfb (talk) 04:25, 13 March 2019 (UTC)
 * I have yet to see a source that explicitly details what Blocks 1–3 of a Full Thrust are. Your assertion that "the lack of information how the first three blocks of Full Thrust differed is not relevant here either" is absurd. We need to know their existence and what exactly the nature of their existence is before we say that they do indeed exist. This is basic logic... The answer to "What is this?" should never be "I don't know" if you want to prove the existence of something. – PhilipTerryGraham (talk &middot;&#32;articles &middot;&#32;reviews) 05:29, 13 March 2019 (UTC)
 * We know they exist. Well, existed. That is backed by references. We don't need to know if their grid fins were different or other details like that. This is not an article about the first three blocks. --mfb (talk) 08:13, 13 March 2019 (UTC)
 * But we need this information so we can rewrite the Falcon 9 and Falcon 9 Full Thrust articles, along with reworking various other articles that don't reflect the lineage that you claim, such as List of Falcon 9 and Falcon Heavy launches, and though you claim that is "backed by references", so far you've given me none that go further than "we think they existed". – PhilipTerryGraham (talk &middot;&#32;articles &middot;&#32;reviews) 11:55, 13 March 2019 (UTC)
 * We have references that Block 5 is the fifth version of Full Thrust. What else do you need as evidence that there were four before? More news discussing them? The article says B1023 and B1025 were Block 2. --mfb (talk) 12:31, 13 March 2019 (UTC)
 * I think it'd be best to move this particular point of discussion to Talk:Falcon 9. – PhilipTerryGraham (talk &middot;&#32;articles &middot;&#32;reviews) 15:40, 13 March 2019 (UTC)


 * The wikipedia article is meant for a broader audiance than the reddit community and enthusiast websites. The original request clearly established that this is the commonly used name for more public facing articles and by most internet discussions. Even though Falcon 9 Full Thrust Block 5 is the name reflecting the development process better MOS:JARGON would probably probably apply.Trialpears (talk) 07:56, 13 March 2019 (UTC)


 * Support – Falcon 9 Block 5 is the common name used in most sources. — JFG talk 07:41, 14 March 2019 (UTC)
 * Support - here again for better visibility. --mfb (talk) 14:36, 15 March 2019 (UTC)
 * Support - Even if Falcon 9 Full Thrust Block 5 is more accurate (which is disputed) the article should use the more common name. I would concider the current name to be in conflict with MOS:JARGON Trialpears (talk) 15:57, 16 March 2019 (UTC)
 * The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Payload Capacity
The chart on the side states that the payload capacity to GTO in recoverable mode is 5500 kg, but the booster was recovered after both the Telstar 18V and 19V launches, and they both weighed over 7000 kg. I don't know what the correct payload capacities are, even SpaceX's own website does not say, but the ones listed here are erroneous. — Preceding unsigned comment added by 104.188.113.221 (talk) 01:24, 10 April 2019 (UTC)
 * Both were released into orbits with a lower apogee (~18,000 km). GTO-like, but the apogee was below the geostationary orbit. They had to do more orbit-raising on their own. --mfb (talk) 12:46, 10 April 2019 (UTC)

Total launches, not including Falcon Heavy
The current count in the infobox states 13 launches. After the latest Falcon Heavy launch this month, would that be 16 -since one FH consists of three F9s ? Or perhaps we should specify these are single F9 launches? Rowan Forest (talk) 16:22, 21 April 2019 (UTC)
 * The Falcon Heavy is not a Falcon 9 and thus should not be included in the launches. Adding a section about Falcon Heavy Block 5 may be a good idea though. Trialpears (talk) 20:59, 21 April 2019 (UTC)
 * Exactly. — JFG talk 00:01, 22 April 2019 (UTC)

Classification Problem : medium or heavy lift
Falcon 9 has a payload capacity of 22800 kg.22800 kg is larger than 20000kg which means that it should be a heavy-lift launch vehicle instead of a medium-lift launch vehicle. —Asdfugil (talk) 08:19, 30 June 2019 (UTC)
 * In heavy-lift launch vehicle it is called "unproven". It should be able to launch so much but it has never done so. With Falcon Heavy operational it is unlikely to ever do this (unless they can do it reusable somehow), SpaceX prefers a reusable FH flight over an expendable F9 flight. --mfb (talk) 09:16, 30 June 2019 (UTC)

Would it be appropriate to put a note that says something along the lines of 'While the Falcon 9 Block 5 has a stated maximum payload capacity above 20,000 Kg, which would classify it as a heavy launch booster, it has yet to attempt such a feat.'AmigaClone (talk) 07:23, 20 August 2020 (UTC)
 * For all practical purpose it's a medium lift vehicle. The theoretical ability to (barely) be in a higher class can be mentioned somewhere but shouldn't go into the lead I think. It's unlikely to ever launch over 20 tonnes. It would need a modified payload adapter and SpaceX would prefer flying such a mission of Falcon Heavy, recovering the boosters. --mfb (talk) 08:07, 20 August 2020 (UTC)

A Commons file used on this page or its Wikidata item has been nominated for deletion
The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 07:57, 6 March 2021 (UTC)
 * Falcon 9 Demo-2 Launching 6 (3).jpg
 * That will likely stay, no action needed at this time. --mfb (talk) 09:10, 6 March 2021 (UTC)

Were any of the block 5 changes to the 2nd stage
Were any of the block 5 changes to the 2nd stage ? Could article confirm if/that "Block 5" applies to 2nd stage too? - Rod57 (talk) 10:31, 19 June 2021 (UTC)


 * Presumably the Block 5 second stages use the redesigned composite overwrapped pressure vessels (COPV 2.0) used by the boosters. The COPVs in the liquid oxygen tank of the second stage were what led to the loss of the Amos 6 satellite and while not the same issue, were involved in the issue that caused the loss of CRS-7. I have no idea when they were adopted. AmigaClone (talk) 03:04, 27 May 2022 (UTC)

How was Falcon 9 Started?/ The history of Space X./ How falcon started.
The Falcon 9 User’s Guide is a planning document for potential and current Space Exploration Technologies (SpaceX) customers. This document is not intended for detailed design use. Data for detailed design purposes will be exchanged directly between a SpaceX Mission Manager and the Payload Provider. This User's Guide highlights the Falcon 9 Block 2 launch vehicle and launch service. The Block 2 launch vehicle offers improved mass‐to‐orbit performance when compared to the Falcon 9 Block 1. Specific differences between Block 1 and Block 2 will be identified, when appropriate. Performance and environment information is based upon Falcon 9 requirements and analyses but is not yet validated by flight data. In an era when most technology‐based products follow a path of ever‐increasing capability and reliability while simultaneously reducing costs, today’s launch vehicles are little changed from those of 40 years ago. SpaceX is changing this paradigm with a family of launch vehicles that will ultimately reduce the cost and increase the reliability of the access to space. Coupled with the newly emerging market for private and commercial space transport, this new model will re-ignite humanity's efforts to explore and develop space. SpaceX was founded on the philosophy that simplicity, reliability, and low cost are closely coupled. We approach all elements of launch services with a focus on simplicity to both increase reliability and lower cost. The SpaceX corporate structure is flat and business processes are lean, resulting in both fast decision-making and delivery. SpaceX products are designed to require low infrastructure facilities (production and launch) with low maintenance overhead, while vehicle design teams are co‐located with production and quality assurance staff to tighten the critical feedback loop. The result is highly producible and low-cost designs with quality embedded. To better understand how SpaceX can achieve low cost without sacrificing reliability, please see the Frequently Asked Questions at www.spacex.com. Established in 2002 by Elon Musk, the founder of PayPal and the Zip2 Corporation, SpaceX has already developed a light lift launch vehicle, the Falcon 1, nearly completed the development of the Falcon 9, and developed state-of-the-art testing and launch locations. In addition, NASA has selected the SpaceX Falcon 9 launch vehicle and Dragon spacecraft for the International Space Station (ISS) Cargo Resupply Services (CRS) contract award. The contract is for a guaranteed minimum of 20,000 kg to be carried to the International Space Station. The firm contracted value is $1.6 billion and NASA may elect to order additional missions for a cumulative total contract value of up to $3.1 billion. SpaceX is on sound financial footing as we move towards volume commercial launches. Their design and manufacturing facilities are conveniently located near the Los Angeles International airport. This location allows the company to leverage the deep and rich aerospace talent pool in Southern California. The SpaceX state‐of‐the‐art propulsion and structural test facilities are located in Central Texas. Drawing upon a rich history of prior launch vehicle and engine programs, SpaceX is privately developing the Falcon family of rockets from the ground up, including main and upper‐stage engines, the cryogenic tank structure, avionics, guidance & control software, and ground support equipment. With the Falcon 1, Falcon 1e, Falcon 9, and Falcon 9 Heavy launch vehicles, SpaceX can offer a full spectrum of light, medium, and heavy lift launch capabilities to our customers. We can deliver spacecraft to any inclination and altitude, from low Earth orbit (LEO) to geosynchronous orbit (GEO) to planetary missions. The Falcon 9 and Falcon 9 Heavy are the only US launch vehicles with true engine‐out reliability. They are also designed such that all stages are reusable, making them the world's first fully reusable launch vehicles. The Dragon crew and cargo capsule, in conjunction with our Falcon 9, have been selected by NASA to provide efficient and reliable transport of cargo and potentially crew to the International Space Station (ISS) and other LEO destinations. To facilitate and streamline communication, each customer works with a single SpaceX contact, a Mission Manager. The Mission Manager works closely with the customer, SpaceX technical execution staff, and all associated licensing agencies to achieve a successful mission. Specifically, the SpaceX Mission Manager is responsible for coordinating mission integration analysis and documentation deliverables, planning integration meetings and reports, and coordinating all integration and test activities associated with the mission. The Mission Manager will also facilitate customer insight during the launch campaign. Though the launch operations team is ultimately responsible for customer hardware and associated Ground Support Equipment (GSE), the Mission Manager will coordinate all launch site activities to ensure customer satisfaction during this critical phase. The vast majority of launch vehicle failures in the past two decades can be attributed to three causes: engine, avionics, and stage separation failures. An analysis by Aerospace Corporation1 showed that 91% of known failures can be attributed to those subsystems. With this in mind, Falcon 9 launch vehicles are designed for high reliability starting at the architectural level and incorporate the flight‐proven design and features of the Falcon 1 launch vehicle. Some of the significant contributors to reliability include • Robust design margins Falcon 9 is designed to carry humans into space aboard the SpaceX Dragon capsule. This goal drives the initial design of Falcon 9 through the incorporation of increased factors of safety (1.4 versus the traditional 1.25 for uncrewed flight). Payload customers using the Falcon 9 can take advantage of this increased design robustness. The first and second stages are also designed to be recovered and reused, and therefore, must have significantly higher margins than an expendable stage. This also provides a unique opportunity to examine recovered hardware and assess design and material selection to continually improve Falcon 9. • Propulsion and separation event design The heart of Falcon 9 propulsion is the Merlin 1C liquid propellant rocket engine. The Merlin engine features a robust, reliable turbopump design incorporating a single shaft for both the liquid oxygen and fuel pumps, and a gas generator cycle versus the more complex staged combustion. The regeneratively‐cooled thrust chamber uses a milled copper alloy liner chamber that provides large margins on heat flux. In addition, the pintle injector was selected for its inherent combustion stability. As a part of our launch operations, we hold the first stage after ignition and monitor the engine before release to watch engine trends. If an off‐nominal condition exists, an autonomous abort is conducted. This helps prevent an engine performance issue from causing a failure in flight. Falcon 9 makes use of ten Merlin 1C engines on each vehicle (nine in the first stage, one in the second stage) resulting in high-volume engine production, which results in much higher quality through process control. Flying ten engines on each mission also builds substantial heritage quickly. Importantly, by employing nine first-stage engines, SpaceX debuts the world’s first Evolved Expendable Launch Vehicle (EELV)‐class launch vehicle with engine‐out capability through much of first-stage flight. With the qualification and first flight units in build and several domestic and international purchased flights currently manifested, Falcon 9 is an ideal workhorse for payload customers. SpaceX has also minimized the number of stages (2) to minimize separation events. The separation system between the first and second stages does not incorporate electro-explosive devices, instead relying upon a pneumatic release and separation system that allows for acceptance testing of the actual flight hardware. This is not possible with a traditional explosive‐based separation system. • Failure mode minimization SpaceX minimized the number of failure modes by minimizing the number of separate subsystems. The first stage thrust vector control (TVC) system makes use of pressurized. rocket-grade kerosene (RP‐1). The engine pulls from the high-pressure RP‐1 side of the pump to power the TVC. This eliminates the separate hydraulic system. In addition, it eliminates the failure mode associated with running out of pressurized fluid. Also, the avionics and guidance/navigation/control systems are designed with single fault tolerance, supporting the ability of Falcon 9 to be human-rated. • Rigorous testing     In addition to SpaceX’s unique design decisions, Falcon 9 will undergo an exhaustive series of tests from the component to the vehicle system level. This includes component level qualification and workmanship testing, structures load and proof testing, flight system and propulsion subsystem level testing, full first and second stage testing up to full system testing, including stage static firings at the test and launches sites (as appropriate). In addition to testing environmental extremes (plus margin), all hardware is tested to account for off‐nominal conditions. For example, both stage and fairing separation tests require testing for off‐nominal cases concerning geometrical misalignment, anomalous pyro timing, and sequencing. A major contributor to a reliable system is its operations. To support robust launch operations, the SpaceX launch countdown is fully automated with thousands of checks made before vehicle release. After first-stage ignition, the vehicle is not released until the first-stage engines are confirmed to be operating normally. A safe shutdown is executed, should any off-nominal conditions be detected. Falcon 9 benefits from the design and operations concepts established for and proven with the successful Falcon 1 program. Pricing includes range, standard payload integration, and third-party liability insurance. Please see Section 5.4 for a description of the standard services. Non‐standard services are also available. If non-standard services are required, please identify these in the Payload Questionnaire found in Section 8 of this Guide. 2001:8F8:1737:F509:498D:9CF6:E3F7:9F8C (talk) 14:14, 30 November 2022 (UTC)

Falcon 9 Overveiw.
Vehicle Overview -2.1. Falcon 9 Launch Vehicles Falcon 9 Launch Vehicles are designed to provide breakthrough advances in reliability, cost, and time to launch. The primary design driver is, and will remain, reliability. SpaceX recognizes that nothing is more important than getting a customer’s payload safely to its intended destination. The initial flights of the Falcon 9, currently planned in 2009 and 2010, use the Falcon 9 Block 1. Beginning in late 2010/early 2011, SpaceX will begin launching the Falcon 9 Block 2. Block 2 features increased engine thrust, decreased launch vehicle dry mass, and increased propellant load ‐ combined with lessons learned from the flights of the Falcon 9 Block 1. This results in increased mass‐to‐orbit performance for the Falcon 9 Block 2 when compared with Block 1 performance. This performance is shown in the Falcon 9 performance tables presented later in this document. 2.1.1. Structure and Propulsion Like Falcon 1, Falcon 9 is a two‐stage, liquid oxygen (LOX) and rocket grade kerosene (RP‐1) powered launch vehicle. It uses the same Merlin engines, structural architecture (with a wider diameter), and launch control system. The Falcon 9 propellant tank walls and domes are made from an aluminum lithium alloy. SpaceX uses an all friction stir welded tank, the highest strength and most reliable welding technique available. Like Falcon 1, the Falcon 9 interstage, which connects the upper and lower stages, is a carbon fiber aluminum core composite structure. The separation system is a larger version of the pneumatic pushers used on Falcon 1. Nine SpaceX Merlin engines power the Falcon 9 first stage with 125,000 lbf sea level thrust per engine, for a total thrust on liftoff of just over 1.1 million lbf. After engine start, Falcon 9 is held down until all vehicle systems are verified as functioning normally before release for liftoff. The second stage tank of Falcon 9 is simply a shorter version of the first stage tank and uses most of the same tooling, material and manufacturing techniques. This results in significant cost savings in vehicle production. A single Merlin engine powers the Falcon 9 upper stage with an expansion ratio of 117:1 and a nominal burn time of 345 seconds. For added reliability of restart, the engine has dual redundant pyrophoric igniters (TEA‐TEB). The Falcon 9 fairing is 17 ft (5.2 m) in diameter. 2.1.2. Avionics, Guidance/Navigation/Control, Flight Termination Systems Falcon 9 vehicle avionics features a single‐fault tolerant architecture and has been designed with a view towards human‐rating requirements in order to allow future qualification for Falcon 9 User’s Guide  SCM 2008‐010 Rev. 1 Copyright ‐‐ SpaceX 2009 9 crewed launch capability. Avionics include rugged flight computers, GPS receivers, inertial measurement units, SpaceX‐designed and manufactured controllers for vehicle control (propulsion, valve, pressurization, separation, and payload interfaces), and a C‐Band transponder for Range Safety tracking. Falcon 9 transmits telemetry from both the first and second stages, even after separation of the stages. S‐band transmitters are used to transmit telemetry and video to the ground. The guidance and navigation algorithms for Falcon 9 launch vehicles have been heavily influenced by the algorithms used on other launch vehicles, including Falcon 1. The guidance system takes into account the loss of an engine during first stage burn and adjusts the targeted trajectory accordingly. This mix of explicit and perturbation guidance schemes was selected in order to generate a smooth, computationally simple trajectory while maintaining orbital insertion accuracies. The Falcon 9 launch vehicle is equipped with a standard flight termination system. This system includes two redundant strings of command receiver and encoder, batteries, safe and arm devices, and ordnance in the event of an anomaly in flight. 2001:8F8:1737:F509:498D:9CF6:E3F7:9F8C (talk) 14:18, 30 November 2022 (UTC)

Grammar?
"The upgrades afforded the second stage with the endurance needed to inject the payloads directly into geosynchronous or high energy orbit where the second stage needs hours after launch" this can't be right. How 'bout

"The upgrades endowed the second stage with the endurance needed to inject the payloads directly into geosynchronous or high energy orbit where the second stage needs to be able to reignite hours after launch" ?

(Errors: afforded or endowed with; needs what?). Good? RudolfoMD (talk) 05:09, 22 September 2023 (UTC)

Failures
No failures till today? 2001:9E8:CACF:5800:CC55:D25E:90D0:AFFE (talk) 18:44, 15 July 2024 (UTC)