Space X falcon-users-guide-2021
Space X falcon-users-guide-2021
Space X falcon-users-guide-2021
@financepresentations1 month ago
FALCON
COPYRIGHT
Subject to the existing rights of third parties, Space Exploration Technologies Corp. (SpaceX) is the owner of the copyright in this work, and no portion hereof is to be copied, reproduced, or disseminated without the prior written consent of SpaceX.
- Gravity is aligned to vecior while vertical
- vectors are always orthogonal to the gravity vector
- 1. Release of the launch vehicle hold-down at liftoff.
- 2. Booster separation (Falcon Heavy only).
- 3. Stage separation.
- 4. Fairing deployment.
- 5. Spacecraft separation.
- 1. Low Frequency (0 - 100Hz)
- a. Excitations driven by global vehicle motion and modes
- b. CLA and sine vibration envelope this region
- 2. Mid Frequency (100Hz - 600Hz)
- a. Excitation due to aeroacoustics
- b. Acoustic excitation and aero buffet are primary drivers in this region
- 3. High Frequency (600Hz - 2000Hz)
- a. Excitation due to structure-borne vibration
- b. MVac forcing functions
- 1. Be a preferential path for lightning in order to prevent direct attachments to personnel and hardware in the protection zone.
- 2. Avoid side flash between the overhead wires and flight hardware and ground systems.
- 3. Minimize electromagnetic coupling to flight hardware and ground systems in order to protect sensitive electronics.
The Falcon launch vehicle user's guide is a planning document provided for customers of SpaceX (Space Exploration Technologies Corp.). This document is applicable to the Falcon vehicle configurations with a 5.2 m (17-ft) diameter fairing and the related launch service (Section 2).
This user's guide is intended for pre-contract mission planning and for understanding SpaceX's standard services. The user's guide is not intended for detailed design use. Data for detailed design purposes will be exchanged directly between a SpaceX customer and a SpaceX mission manager.
SpaceX reserves the right to update this user's guide as required. Future revisions are assumed to always be in process as SpaceX gathers additional data and works to improve its launch vehicle design.
SpaceX offers a family of launch vehicles that improves launch reliability and increases access to space. The company was founded on the philosophy that simplicity, reliability and cost effectiveness are closely connected. 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 fast decision-making and product delivery. SpaceX products are designed to require low-infrastructure facilities with little overhead, while vehicle design teams are colocated with production and quality assurance staff to tighten the critical feedback loop. The result is highly reliable and producible launch vehicles with quality embedded throughout the process.
Established in 2002 by Elon Musk, the founder of Tesla Motors, PayPal and the Zip2 Corporation, SpaceX has developed and flown the Falcon 1 light-lift launch vehicle, the Falcon 9 medium-lift launch vehicle, the Falcon Heavy heavy-lift launch vehicle, the most powerful operational rocket in the world by a factor of two, and Dragon, which is the first commercially produced spacecraft to visit the International Space Station.
SpaceX has built a launch manifest that includes a broad array of commercial, government and international customers. In 2008, NASA selected the SpaceX Falcon 9 launch vehicle and Dragon spacecraft for the International Space Station Cargo Resupply Services contract. NASA has also awarded SpaceX contracts to develop the capability to transport astronauts to space as well as to launch scientific satellites. SpaceX's first crewed test flight with the Crew Dragon spacecraft launched in May 2020, carrying NASA astronauts Douglas Hurley and Robert Behnken to the International Space Station and safely returning them to Earth two months later. NASA has certified the Falcon 9 / Crew Dragon system for human spaceflight, and SpaceX is providing operational missions to the International Space Station under the Commercial Crew Program, as well providing the capability to launch commercial astronauts to space. In addition, SpaceX services the National Security community and is on contract with the U.S. Space Force for multiple missions on the Falcon family of launch vehicles.
SpaceX has state-of-the-art production, testing, launch and operations facilities. SpaceX design and manufacturing facilities are conveniently located near the Los Angeles International Airport. This location allows the company to leverage Southern California's rich aerospace talent pool. The company also operates cutting-edge propulsion and structural test facilities in Central Texas, along with launch sites in Florida and California, and a commercial orbital launch site in development in South Texas.
Drawing on a history of prior launch vehicle and engine programs, SpaceX privately developed the Falcon family of launch vehicles. Component developments include first- and second-stage engines, cryogenic tank structures, avionics, guidance and control software, and ground support equipment.
With the Falcon 9 and Falcon Heavy launch vehicles, SpaceX is able to offer a full spectrum of medium- and heavy-lift launch capabilities to its customers (Figure 1-1), as well as small and micro satellite launch capabilities via its Rideshare Program. SpaceX currently operates Falcon launch facilities at Cape Canaveral Space Force Station (CCSFS), Kennedy Space Center (KSC), and Vandenberg Space Force Base (VSFB) and can deliver payloads to a wide range of inclinations and altitudes, from low Earth orbit (LEO) to geosynchronous transfer orbit (GTO) to escape trajectories for interplanetary missions.
The Falcon family has conducted successful flights to the International Space Station (ISS), LEO, highly elliptical orbit (HEO), GTO, and Earth-escape trajectories. As of the end of 2020, SpaceX has completed over 100 Falcon launches, making it the most flown U.S. launch vehicle currently in operation.
Reusability is an integral part of the Falcon program. SpaceX pioneered reusability with the first re-flight of an orbital class rocket in 2017. As of August 2021, SpaceX has re-flown rockets more than 65 times, with a 100% success rate. Since 2018, SpaceX had more missions launching with a flight-proven rocket than a first flight rocket. SpaceX also started re-flying fairings in late 2019, and as of the end of 2020 has re-flown more than 40 fairing halves with a 100% success rate. By re-flying boosters and fairings, SpaceX increases reliability and improves its designs and procedures by servicing and inspecting hardware as well as incorporating lessons that can only be learned from flight.
The Falcon launch vehicles were designed from the beginning to meet NASA human-rated safety margins. We continue to push the limits of rocket technology as we design the safest crew transportation system ever flown while simultaneously advancing toward fully reusable launch vehicles. Our emphasis on safety has led to advancements such as increased structural factors of safety, greater redundancy and rigorous fault mitigation. Because SpaceX produces one Falcon core vehicle, satellite customers benefit from the high design standards required to safely transport crew. The major safety features are listed in more detail in Table 1-1.
A study 1 by The Aerospace Corporation found that 91% of known launch vehicle failures in the previous two decades can be attributed to three causes: engine, avionics, and stage separation failures. With this in mind, SpaceX incorporated key engine, avionics, and staging reliability features for high reliability at the architectural level of Falcon launch vehicles. Significant contributors to reliability include:
As of the end of 2020, the Merlin engine that powers the Falcon family of launch vehicles is the only new hydrocarbon engine to be successfully developed and flown in the U.S. in the past 40 years. It has the highest thrust-weight ratio of any boost engine ever made. The liquid-propelled Merlin powers the Falcon propulsion system. The engine features a reliable turbopump design with a single shaft for the liquid oxygen pump, the fuel pump, and the turbine. The engine uses a gas generator cycle instead of the more complex staged combustion cycle. The regeneratively cooled nozzle and thrust chamber use a milled copper alloy liner that provides large heat flux margins. A pintle injector provides inherent combustion stability.
Engine failure modes are minimized by eliminating separate subsystems where appropriate. For example, the first-stage thrust vector control system pulls from the high-pressure rocket-grade kerosene system, rather than using a separate hydraulic fluid and pressurization system. Using fuel as the hydraulic fluid eliminates potential failures associated with a separate hydraulic system and with the depletion of hydraulic fluid.
The high-volume engine production required to fly 10 Merlin engines (Falcon 9) or 28 engines (Falcon Heavy) on every launch results in high product quality and repeatability through process control and continuous production. Flying several engines on each mission also quickly builds substantial engineering data and flight heritage.
During Falcon launch operations, the first stage is held on the ground after engine ignition while automated monitors confirm nominal engine operation. An autonomous safe shutdown is performed if any off-nominal condition is detected. Hold-on-pad operations, enabled by the launch vehicle's all-liquid propulsion architecture and autonomous countdown sequence, significantly reduce risks associated with engine start-up failures and underperformance.
By employing multiple first-stage engines, SpaceX offers the world's first evolved expendable launch vehicle (EELV)class system with engine-out capability through much of first-stage flight. System-level vehicle management software controls the shutdown of engines in response to off-nominal engine indications; this has been demonstrated in flight, with 100% primary mission success. Although the likelihood of catastrophic engine failure is low, and failing engines are designed to be shut down prior to a catastrophic failure, each engine is housed within its own metal bay to isolate it from neighboring engines.
The second-stage Merlin Vacuum engine uses a fixed, non-deploying expansion nozzle, eliminating potential failure modes in nozzle extension.
Falcon launch vehicle avionics, and guidance, navigation and control systems use a fault-tolerant architecture that provides full vehicle single-fault tolerance and uses modern computing and networking technology to improve performance and reliability. The fault tolerance is achieved either by isolating compartments within avionics boxes or by using triplicated units of specific components. Both the first and second stages host their own multiple redundant lithium-ion batteries to minimize the complexity of the electrical interface.
The two-stage Falcon 9 architecture was selected to minimize the number of stage separation events, eliminating potential failure modes associated with third- and fourth-stage separations, as well as potential engine deployment and ignition failure modes in the third and fourth stages. Falcon Heavy uses the same stage architecture as Falcon 9 with the addition of two separating side cores.
The Falcon second-stage and Falcon Heavy side-boosters restraint, release, and separation systems use pneumatic devices that provide low-shock release and positive force separation over a comparatively long stroke. The pneumatic system allows for acceptance and functional testing of the actual flight hardware, which is not possible with a traditional explosives-based separation system.
For each Falcon launch vehicle, SpaceX performs an exhaustive series of tests from the component to the vehicle system level. The test program includes component-level flight acceptance and workmanship testing, structures load and proof testing, flight system and propulsion subsystem-level testing, and full first- and second-stage testing up to full system testing (including first- and second-stage static fire testing). In addition to testing environmental extremes (plus margin), flight critical and workmanship sensitive hardware are tested to account for off-nominal conditions. For example, stage separation tests are performed for off-nominal cases with respect to geometrical misalignment, anomalous timing and sequencing.
The Falcon first stage is designed to survive atmospheric entry and to be recovered, handling both the rigors of the ascent portion of the mission and the loads of the recovery portion. Stage recoverability also provides a unique opportunity to examine recovered hardware and assess design and material selection in order to continually improve Falcon 9 and Falcon Heavy.
The standard price for Falcon 9 and Falcon Heavy launch services can be found at https://www.spacex.com/media/Capabilities&Services.pdf. Pricing includes range services, standard payload
integration and third-party liability insurance. Please see Section 7.3 for a complete description of standard services. Nonstandard services are also available.
Descriptions and performance information in this user's guide are for the Falcon 9 and Falcon Heavy fairing configuration; please contact SpaceX for information about Dragon launch capabilities. Table 2-1 provides additional details on Falcon 9 and Falcon Heavy dimensions and design characteristics.
Falcon 9 (Figure 2-1) is a two-stage launch vehicle powered by liquid oxygen (LOX) and rocket-grade kerosene (RP-1). The vehicle is designed, built and operated by SpaceX. Falcon 9 can be flown with a fairing or with a SpaceX Dragon spacecraft. All first- and second-stage vehicle systems are the same in the two configurations; only the payload interface to the second stage changes between the fairing and Dragon configurations.
Falcon 9 was updated in the summer of 2015 to a Full Thrust configuration from its previous v1.1 configuration (flown from 2013 summer 2015). Falcon 9 underwent further updates and first flew its Full Thrust Block 5 configuration in spring 2018. The Falcon 9 Block 5 architecture focused on improving performance, reliability, and life of the vehicle, as well as ensuring the vehicle's ability to meet critical government crewed and non-crewed mission requirements. Engine performance on both stages was improved, releasing additional thrust capability. Thermal protection shielding was modified to support rapid recovery and refurbishment. Avionics designs, thrust structures, and other components were upgraded for commonality, reliability, and performance.
Falcon Heavy (Figure 2-2) is a two-stage, heavy-lift launch vehicle powered by LOX and RP-1. It can transport more payload mass into LEO or GTO than any other launch vehicle currently in operation.
Falcon Heavy is the most powerful launch vehicle in operation with more than 5.1 million pounds of thrust at liftoff. Falcon Heavy builds on the proven, highly reliable design of Falcon 9. Falcon Heavy's first-stage comprises three Falcon 9 first stages with enhancements provided to strengthen the cores. Furthermore, Falcon Heavy utilizes the same second stage and same payload fairing as flown on Falcon 9, fully benefitting from the flight heritage provided by Falcon 9 flights. This commonality has also minimized infrastructure unique to the vehicle. SpaceX first launched the Falcon Heavy vehicle in February of 2018.
INTERSTAGE
The first stage comprises three cores: a center core and two side boosters (the first stage of Falcon 9 is used as a side booster); each core has nine Merlin 1D (M1D) engines. Each of the 27 first-stage engines produces 190,000 lbf of thrust at sea level, for a total of 5,130,000 lbf of thrust at liftoff. The two side boosters are connected to the center core at the base engine mount and at the forward end of the LOX tank on the center core.
With nine engines in each first-stage core, Falcon Heavy has propulsion redundancy - unlike any other heavy-lift launch system. The launch vehicle monitors each engine individually during ascent and can, if necessary, preemptively command off-nominal engines, provided the minimum injection success criteria are achievable with the remaining engines. This engine-out reliability provides propulsion redundancy throughout first-stage ascent - a feature unique to Falcon launch vehicles.
The first-stage propellant tank walls of the Falcon vehicles are made from an aluminum lithium alloy. Tanks are manufactured using friction stir welding-the highest strength and most reliable welding technique available. A common dome separates the LOX and RP-1 tanks, and a double-wall transfer tube carries LOX through the center of the RP-1 tank to the engine section. Four grid fins near the top of the first stage along with four deployable legs at the base are nominally flown to support recovery operations.
Nine SpaceX Merlin engines power the Falcon 9 first stage with up to 854 kN (190,000 lbf) thrust per engine at sea level, for a total thrust of 7,686 kN (1.71 million lbf) at liftoff. The first-stage engines are configured in a circular pattern, with eight engines surrounding a center engine.
Twenty-seven SpaceX Merlin engines power the Falcon Heavy first stages for a total thrust of 5,130,000 lbf at liftoff. The figure below shows the nomenclature for the center core and side boosters (center, plus y-axis and minus y-axis.) Structurally, the plus y-axis and minus y-axis boosters are identical. The center core consists of thicker tank walls and carries the booster separation system. The z axis points to zenith when the vehicle is horizontal.
After engine start, Falcon vehicles are held down until all vehicle systems are verified as functioning normally before release for liftoff.
The Falcon vehicles' interstage, which connects the first and second stages, is a composite structure consisting of an aluminum honeycomb core surrounded by carbon fiber face sheet plies. The interstage is fixed to the forward end of the first-stage tank. The stage separation system is located at the forward end of the interstage and interfaces to the secondstage.
The second-stage tank for Falcon vehicles is a shorter version of the first-stage tank and uses most of the same materials, construction, tooling and manufacturing techniques as the first-stage tanks. A single Merlin Vacuum (MVac) engine powers the second stage, using a fixed 165:1 expansion nozzle. For added reliability of restart, the engine contains dual redundant triethylaluminum-triethylborane (TEA-TEB) pyrophoric igniters. In addition, the second stage contains a cold nitrogen gas (GN2) attitude control system (ACS) for pointing and roll control. The GN2 ACS is more reliable and produces less contamination than a propellant-based reaction control system.
The first and second stages are mated by mechanical latches at three points between the top of the interstage and the base of the second-stage fuel tank. After the first-stage engines shut down, a high-pressure helium circuit is used to release the latches via redundant actuators. The helium system also preloads four pneumatic pushers, which provide a positive-force for stage separation after latch release. This includes a redundant center pusher to further decrease the probability of re-contact between the stages following separation.
The two halves of the standard fairing are fastened by mechanical latches along the fairing vertical seam. To deploy the fairing, a high-pressure helium circuit releases the latches, and four pneumatic pushers facilitate positive-force deployment of the two halves. The use of all-pneumatic separation systems provides a benign shock environment, allows acceptance and preflight testing of the actual separation system hardware, and minimizes debris created during separation.
The two halves of the extended fairing are fastened by a bolted frangible seam joint. To deploy the fairing, redundant detonators initiate a detonation cord contained inside an expanding tube assembly. The detonation causes the expanding tube to expand outwards and break the structural seam between the two fairings in a controlled and contained manner. Four pneumatic pushers facilitate positive-force deployment of the two halves. The use of a nonbolted clamshell interface between the payload fairing and the rest of the vehicle provides significant shock attenuation of the separation event, maintaining environments for the payload well within nominal payload requirements.
For Falcon Heavy, the fundamental purpose of the side cores is to apply axial force to the center core during ascent and increase the impulse delivered to second stage before stage separation. The timing of the shutdown for the Falcon Heavy side cores can be tailored for each mission to ensure that the proper impulse is delivered. Each side core is structurally connected to the center core at forward and aft locations. Two pneumatic pusher separation mechanisms connect the forward ends of each side core to the center core, fastening the top of the LOX tank in the center core to the side cores. They maintain the connection during ascent and then actively jettison the side cores following side core shutdown. Two identical pusher separation mechanisms connect the aft ends of each side core to the center core and are used to laterally force the base of the side cores from the center core following the side core shut down.
Falcon avionics feature a flight-proven, three-string, fault-tolerant architecture that has been designed to human-rating requirements. Avionics include flight computers, Global Positioning System (GPS) receivers, inertial measurement units, SpaceX-designed and manufactured controllers for vehicle control (propulsion, valve, pressurization, separation and payload interfaces), a network backbone, S-band transmitters and a C-band transponder for range safety tracking. The S-band transmitters are used to transmit telemetry and video to the ground, from both the first and second stages, even after stage separation.
Our launch vehicles are equipped with an autonomous flight termination system (AFTS) to limit the potential damage caused by a launch vehicle malfunction. The system terminates the flight of the vehicle automatically if mission rules are violated. The use of an AFTS requires fewer range assets to support launch operations, resulting in fewer range constraints and increased launch opportunities.
Falcon vehicles use a right-hand X-Y-Z coordinate frame centered 440.69 cm (173.5 in.) aft of the first-stage radial engine gimbal, with +X aligned with the vehicle long axis and +Z opposite the transporter-erector strongback (Figure 2-4). X is the roll axis, Y is the pitch axis, and Z is the yaw axis. Additional coordinate frames may be defined with reference to the payload interface (Section 5.1.1) for specific missions.
SpaceX launch services are offered at its Cape Canaveral Space Force Station, Kennedy Space Center, and Vandenberg Space Force Base launch sites. Together, Cape Canaveral Space Force Station and Kennedy Space Center are referred to herein as the Eastern Range. Additional launch facilities are currently under development in South Texas (Section 6).
Launch services to a range of low Earth orbits are available, including services to low-inclination orbits through highinclination and sun-synchronous orbits (SSO). Falcon vehicles can provide either two-burn or direct-inject launch services: two-burn mission profiles optimize vehicle performance, while direct-inject mission profiles offer reduced mission duration and require only a single start of the second-stage engine. LEO missions to a 55 deg inclination or lower are flown from the Eastern Range (with a performance penalty between 53 and 55 deg due to the need to perform a 'dog leg' maneuver); LEO missions to higher inclinations are baselined to be flown from Vandenberg Space Force Base, but may also be flown from the Eastern Range in specific cases and at SpaceX's discretion (contact SpaceX for more information). Launch services to inclinations lower than 28.5 deg are available from the Eastern Range, but they incur a performance penalty.
Launch services to a range of GTOs and other high-altitude orbits are available, including standard GTO, sub-GTO for heavy payloads, and supersynchronous injection. A perigee altitude of 185 km (100 nmi) is baselined for GTO; higher perigee values may be provided with a performance penalty. Currently, all GTO missions are flown from the Eastern Range.
Launch services directly into geosynchronous orbit (GSO) are available from Kennedy Space Center via Falcon Heavy. The satellite is placed into a circular orbit directly above or below GSO to allow it to phase into its correct orbital position.
Launch services to a range of Earth escape orbits are available. Customers may also utilize a customer-supplied kickstage to achieve higher escape energy (C3) performance, based on mission requirements. Earth escape missions are typically flown from the Eastern Range.
Mass-to-orbit capabilities for the Falcon 9 and Falcon Heavy fairing configuration are available upon request.
The baseline SpaceX payload attach fitting (PAF) shown in Figure 3-1 converts the diameter of the launch vehicle to a (typical) standard 1,575-mm (62.01 in.) bolted interface. SpaceX also offers a PAF with a 2,624-mm (103.307 in.) bolted interface (Figure 3-2). SpaceX can also provide a PAF with a wider interface. Please contact SpaceX for more details.
Payloads should comply with the mass properties limitations given in Figure 3-3 (for the 1575-mm PAF) and Figure 3-4 (for the 2624-mm PAF). Payloads in excess of these figures can be accommodated as a mission unique service. Payload mass properties should be assessed for all items forward of the PAF 1575-mm or 2624-mm bolted interfaces (Section 5.1.1), including any mission-unique payload adapters and separation systems. Mass properties capabilities may be further constrained by mission-unique payload adapters, dispensers or separation systems.
Falcon 1,575 PAF Capability
SpaceX requires that customers verify the mass properties of their system through measurement before shipping it to the launch site. SpaceX may request insight into relevant analyses and testing performed for satellite qualification, acceptance and interface verification. Falcon vehicles may be able to accommodate payloads with characteristics outside the limitations indicated in this section. Please contact SpaceX with your mission-unique requirements.
Falcon launch vehicles can launch any day of the year, at any time of day, subject to environmental limitations and constraints as well as range availability and readiness. Launch window times and durations are developed specifically for each mission. Customers benefit from recycle operations, maximizing launch opportunities within the launch window (Section 8.5.6).
Falcon 9 and Falcon Heavy can provide payload pointing and roll control during long-duration coast phases for sun avoidance and thermal control. If requested, the Falcon second stage will point the X-axis of the launch vehicle to a customer-specified attitude and perform a passive thermal control roll of up to ±1.5 deg/sec around the launch vehicle X-axis, held to a local vertical/local horizontal (LVLH) roll attitude accuracy of ±5 deg.
Falcon launch vehicles offer 3-axis attitude control or spin-stabilized separation as a standard service. For inertial separation, the vehicle will point the second stage and payload to the desired LVLH attitude and minimize attitude rates. For spin-stabilized separation, the Falcon launch vehicle will point the second stage and payload to the desired LVLH attitude and initiate a spin about the launch vehicle X-axis at a customer-specified rate dependent upon payload mass properties. Standard pre-separation attitude and rate accuracies are developed as a mission-specific standard service. More information about separation attitude and rate accuracy is available from SpaceX upon request.
Falcon 9 and Falcon Heavy can launch multiple satellites on a single mission, with the customer responsible for the integration of the multiple payloads. As a liquid-propellant launch vehicle with restart capability, Falcon launch vehicles also provide the flexibility to deploy each satellite into a different orbit, performance allowing. SpaceX also offers dedicated rideshare missions via its Smallsat Rideshare Program.
Falcon launch vehicles can accommodate a broad range of dispenser systems including multi-payload systems and mission-unique adapters. SpaceX can develop and provide such adapters and dispensers if desired, as a nonstandard service, or can integrate third-party systems. Please contact SpaceX with your mission-unique requirements.
SpaceX typically reserves the right to manifest secondary payloads aboard Falcon missions on a non-interference basis. Secondary payloads may be manifested on a variety of secondary payload adapters including a SpaceX-developed Rideshare Dispenser ring, a SpaceX-developed Surfboard, or other mission-unique secondary deployment structures.
Please contact SpaceX or refer to the Rideshare Payload User's Guide for information regarding flight opportunities, interface requirements and pricing for secondary payloads.
Falcon 9 and Falcon Heavy have been designed to provide as benign a payload environment as possible, via the use of all-liquid propulsion, a single staging event, deeply throttleable engines and pneumatic separation systems. The environments presented below reflect typical mission levels for Falcon 9 and Falcon Heavy, and are based on the use of the standard fairing; please contact SpaceX for more information on payload environments for missions requiring the extended fairing. Mission-specific analyses will be performed and documented in an interface control document for each contracted mission.
SpaceX recommends using the quasi-static limit load factors provided by NASA-HDBK-7005 (Table 4-1). SpaceX has quantified the maximum predicted environments experienced by the payload during transportation. Transportation will be accomplished by two wheeled vehicles: a payload transporter from the payload processing facility to the hangar, and the launch vehicle transporter-erector from the hangar to the launch pad. It is expected that transportation environments will be enveloped by the flight environments in Section 4.3.
The standard service temperature, humidity and cleanliness environments during various processing phases are provided in Table 4-2. SpaceX can accommodate environments outside the standard service. Please contact SpaceX for details.
Conditioned air will be disconnected for a short duration during rollout to the pad. Spacecraft environmental temperatures will be maintained above the dew point of the supply air at all times. A nitrogen purge is available as a nonstandard service. The PAF and fairing surface are cleaned to Visibly Clean-Highly Sensitive, achieving a residue level between A/5 and A/2 and particulate between 300-500 micron, per IEST-STD-CC1246D.
The maximum predicted environments the payload will experience from liftoff through separation are described in the sections below. Falcon vehicles may be able to accommodate payloads with characteristics outside the limitations indicated in these sections and may also be able to provide environments lower than those indicated in these sections. Please contact SpaceX with your mission-unique requirements.
During flight, the payload will experience a range of axial and lateral accelerations. Axial acceleration is driven by vehicle thrust and drag profiles; lateral acceleration is primarily driven by wind gusts, engine gimbal maneuvers, first-stage engine shutdown and other short-duration events. Both the first- and second-stage engines may be throttled to help maintain launch vehicle and payload steady state acceleration limits.
For 'standard' payloads with mass of more than 4,000 lb (1,810 kg), Falcon 9 and Falcon Heavy payload design load factors are shown using the envelope in Figure 4-1. For 'light' payloads with mass of less than 4,000 lb (1,810 kg), Falcon 9 load factor is provided in Figure 4-2. For Falcon Heavy 'light' payloads, please contact SpaceX for more details. Provided loads are maximum flight loads (limit level) and do not contain a qualification factor.
The load factors provided below are intended for a single payload mission; multi-payload missions should coordinate directly with SpaceX. A positive axial value indicates a compressive net-center-of-gravity acceleration, while a negative value indicates tension. Actual payload loads, accelerations and deflections are a function of both the launch vehicle and payload structural dynamic properties and can be accurately determined via a coupled loads analysis.
Payloads should consider maintaining the primary lateral frequency above 10Hz, primary axial frequency above 25Hz, and all secondary structure minimum resonant frequencies above 35Hz to avoid interaction with launch vehicle dynamics.
The Falcon 9 and Falcon Heavy design load factors provided below are for typical spacecraft above 4,000 lb, and are applicable to mission that use either the 1,575-mm or the 2,624-mm PAF. Please consult with SpaceX for applicability based on spacecraft modal frequencies and CG height.
Please contact SpaceX for more information.
Maximum predicted sinusoidal vibration environments represent the levels at the top of the payload attach fitting for Q=20 through Q=50, and envelope all stages of flight. Maximum predicted sinusoidal vibration environments for Falcon 9 and Falcon Heavy are shown in Figure 4-3 and Figure 4-4. These environments represent the vibration levels at the top of the PAF for Q=20 through Q=50, and envelope all stages of flight. Provided loads are maximum flight loads (limit level) and do not contain a qualification factor. Since SpaceX accommodates a variety of payloads, results of coupled loads analysis will be used to modify these levels, if necessary, to reflect the levels at the payload interface.
Frequency (Hz)
During flight, the payload will be subjected to a varying acoustic environment. Levels are highest near liftoff and during transonic flight, due to aerodynamic excitation. The acoustic environment, defined as the spatial average and derived at a P95/50 level, is shown by both full-octave and third-octave curves.
The acoustic maximum predicted environment for typical payloads in the SpaceX standard fairing with no acoustic blankets installed is shown in Figure 4-7 and Table 4-5 (third octave) and Figure 4-8 and Table 4-6 (full-octave).
Predicted acoustic levels for a specific mission will depend on the use of acoustic blankets and the payload's size and volume, with smaller payloads generally having lower acoustic levels. Margin for qualification testing or for payloads larger than 60% volume fill is not included in the curves below.
F9 Payload Acoustic MPEs (Full Octave)
Falcon Heavy Payload Acoustic MPE (Third-Octave)
Five events during flight result in loads that are characterized as shock loads:
Of these events, the first three are negligible for the payload relative to fairing deployment and spacecraft separation because of the large distance and number of joints over which the shocks will travel and dissipate. The maximum shock environment predicted at the 1,575-mm interface for fairing deployment is enveloped by the shock environment from typical spacecraft separation. Consequently, the shock environment is typically a function of the spacecraft adapter and separation system selected for the mission. Actual shock environments experienced by the payload at the top of the mission-unique payload adapter will be determined following selection of a specific payload adapter and separation system. Table 4-9 shows typical payload adapter-induced shock at the spacecraft separation plane for 937-mm or 1,194mm or 1,666 mm (36.89 in. or 47.01 in. or 65.59 in.) clampband separation systems, derived at a P95/50 statistical level. Please note the actual flight shock levels produced by the payload adapter will be mission-unique.
The maximum predicted random vibration environment at the top of the PAF can be seen in Figure 4-11 and Table 4-10. This environment is derived from flight data measured at the top of the PAF and does not account for any additional attenuation as the vibration traverses the mission-specific payload adapter or spacecraft interface. The smoothline is an envelope of all flight events (liftoff, Stage 1 ascent, and S2 burns) and is derived at a P95/50 statistical level.
The random vibration environment is derived from the maximum response due to multiple forcing functions. These forcing functions can be broken into three frequency bins as shown in Figure 4-12 and listed below:
Spacecraft complying with standard component-level qualification practices such as GEVs or SMC-S-016 are generally covered for this environment. Spacecraft with sensitive components that are not screened to vibration levels above the Falcon MPE can assess if acoustic testing envelopes the random vibration environment. One approach to determine this is to measure acceleration responses near components during acoustic testing. Components closer to the spacecraft separation plane are more likely to be driven by random vibration as opposed to acoustics than those further away. Spacecraft components with high surface area to mass ratios such as photovoltaic arrays generally see higher
excitations from acoustic environments than from random vibration. However, these criteria are subjective and engineering best judgement should be used.
Frequency (Hz)
Falcon 9/Heavy random vibration environment (5.13 grms)
Spacecraft with sensitive components not screened with standard-level qualifications (GEVS or SMC-S-016) may require additional relief from random vibration. SpaceX offers random vibration attenuation as a nonstandard service. For programmatic information, please reach out to SpaceX directly.
Falcon launch vehicles include several radio frequency (RF) systems, which are summarized in Table 4-11 for Falcon 9 and Table 4-12 for Falcon Heavy.
Payload customers must ensure that payload materials or components sensitive to RF environments are compatible with the worst-case Falcon 9 (Figure 4-13 and Table 4-13) and Falcon Heavy (Figure 4-14 and Table 4-14) launch vehicle radiated environment. These limits envelope expected emissions as calculated at the plane between the PAF and
mission-specific payload adapter and do not include EMI safety margin or emissions from Avionics inside the fairing. Emissions from Avionics located inside the fairing volume are provided in Section 4.3.6.4. Notch requests will be assessed for compatibility on a mission-specific basis; notches for spacecraft receivers can typically be accommodated to the fairing avionics emissions envelope (48 dBuV/m) or lower depending on clearances to the payload dynamic envelope.
Maximum spacecraft emissions for Falcon 9 and Falcon Heavy are shown in Figure 4-15 and Table 4-15. Payloads should not emit radiation in excess of the maximum allowable spacecraft emissions at any time during processing, integration or flight, as measured at the top of the PAF. Standard Falcon services do not permit active payload radiation during the countdown or flight prior to separation from the second stage. This limit envelopes expected emissions as calculated at the plane between the PAF and mission-specific payload adapter and includes EMI safety margin. Notch requests will be assessed for compatibility on a mission-specific basis; notches for spacecraft transmitters can typically be accommodated to a level that is 6dB lower than SpaceX Avionics qualification limits. Please consult with SpaceX for your mission-unique requirements.
Falcon launch vehicles have avionics inside the fairing. The fairing emission level is shown in Figure 4-16 and Table 4-16. This limit envelopes the maximum expected combined emissions from these avionics, as calculated at the surface of the payload volume defined in Figure 12-5 in Appendix A. EMI safety margin is not included.
SpaceX has launch facilities on the East coast (SLC-40 and LC-39A) and on the West coast (SLC-4E). This limit envelopes the expected emissions at all SpaceX integration and launch facilities, including Range sources, local radar systems, and communications systems in use at SpaceX facilities (WiFi, mobile phones, two-way radios, etc.). Spacecraft designed and tested to this limit (plus appropriate safety margin) can expect to be compatible with all known launch site emissions between spacecraft arrival and delivery to orbit. The envelope is calculated at the surface of the spacecraft and EMI safety margin is not included.
Site-specific (not enveloped) analysis will be performed on a mission-specific basis as needed to meet customer requirements. Notches for spacecraft receivers typically do not overlap with launch site emissions frequencies and can typically be accommodated.
To account for unexpected variation in hardware and environments, 6dB of EMI safety margin is required. EMI safety margin is typically expected to be included on the 'victim' side of the source-victim analysis. Each emissions section in this guide specifies whether safety margin has been included in the envelope provided. When safety margin has not been included, it is expected that the relevant spacecraft susceptibility limit will include 6dB of EMI safety margin.
SpaceX launch pads at CCSFS/KSC contain full lightning protection systems. The integration facilities and hangars are equipped with lightning grounding systems to protect personnel and hardware from lightning. The SLC-40 and LC-39A launch pads are equipped with overhead wire lightning protection systems. These systems are designed to:
Well-defined lightning retest criteria are important to minimize both the risk of damage and the risk of missed launch opportunities for spacecraft and launch vehicles. As such, Falcon launch vehicles have well-defined lightning retest criteria that are based on the lightning distance and amplitude data measured using range-provided lightning monitoring systems. SpaceX requires spacecraft to provide lightning retest criteria based on lightning strike distance and amplitude.
Inside the Falcon launch vehicle, the payload fairing internal pressure will decay at a rate no larger than 0.40 psi/sec (2.8 kPa/sec) from liftoff through immediately prior to fairing separation, except for brief periods during flight, where the payload fairing internal pressure will decay at a rate no larger than 0.65 psi/sec (4.5 kPa/sec), for no more than 5 seconds.
The SpaceX payload fairing is a composite structure consisting of a 2.5-cm (1-in.) thick aluminum honeycomb core surrounded by carbon fiber face sheet plies. The emissivity of the payload fairing is approximately 0.9. The fairing thermal insulation, which is attached to the outside of the fairing composite, is sized such that the composite never exceeds the Bounding Fairing Composite Temperature profile shown in Figure 4-18. The curve is truncated at 240 seconds, although the approximate time of payload fairing jettison for a GTO mission from Cape Canaveral is typically earlier, at around 210 seconds into flight. Payload fairing jettison timing is determined by customer requirements and physical limitations of the system.
Bounding Fairing Composite Temperature
The payload fairing will nominally be deployed when free molecular aero-thermal heating is less than 1,135 W/m 2 . Other fairing deployment constraints can be accommodated as a standard service, although they may modestly reduce vehicle performance. Please contact SpaceX regarding mission-unique fairing deployment requirements.