Falcon Heavy

Falcon Heavy

Artist's representation of Falcon Heavy Reusable on launchpad
Function	Orbital super heavy-lift launch vehicle Potential Lunar or Martian launch vehicle[1]
Manufacturer	SpaceX
Country of origin	United States
Cost per launch	$90M for up to 8,000 kg to GTO [2]
Size
Height	70 m (230 ft)[3]
Diameter	3.66 m (12.0 ft)[3]
Width	12.2 m (40 ft)[3]
Mass	1,420,788 kg (3,132,301 lb)[3]
Stages	2+
Capacity
Payload to LEO (28.5°)	54,400 kg (119,900 lb)[3]
Payload to GTO (27°)	22,200 kg (48,900 lb)[3]
Payload to Mars	13,600 kg (30,000 lb)[3]
Payload to Pluto	2,900 kg (6,400 lb)[3]
Associated rockets
Family	Falcon 9
Comparable	Delta IV Heavy, Angara A5V, Saturn C-3
Launch history
Status	In development
Launch sites	Kennedy LC-39A Vandenberg SLC-4E[4]
Total launches	0
Successes	0
Failures	0
First flight	November 2016 (planned)[5]
Boosters
No. boosters	2
Engines	9 Merlin 1D
Thrust	Sea level: 7,607 kN (1,710,000 lbf) Vacuum: 8,227 kN (1,850,000 lbf)
Total thrust	(boosters plus core)[3] Sea level: 22,819 kN (5,130,000 lbf) Vacuum: 24,681 kN (5,549,000 lbf)
Specific impulse	Sea level: 282 seconds[6] Vacuum: 311 seconds[7]
Burn time	162 seconds[8]
Fuel	Subcooled LOX / Chilled RP-1[9]
First stage
Engines	9 Merlin 1D
Thrust	Sea level: 7,607 kN (1,710,000 lbf) Vacuum: 8,227 kN (1,850,000 lbf)[8]
Specific impulse	Sea level: 282 seconds Vacuum: 311 seconds
Burn time	162 seconds
Fuel	Subcooled LOX / Chilled RP-1
Second stage
Engines	1 Merlin 1D Vacuum
Thrust	934 kN (210,000 lbf)[3]
Specific impulse	348 seconds[8]
Burn time	397 seconds[3]
Fuel	LOX / RP-1

Falcon Heavy (FH), previously known as the Falcon 9 Heavy, is a super heavy lift space launch vehicle being designed and manufactured by SpaceX. The Falcon Heavy is a variant of the Falcon 9 launch vehicle and will consist of a standard Falcon 9 rocket core, with two additional strap-on boosters derived from the Falcon 9 first stage.^[10] This will increase the low Earth orbit (LEO) payload to 54.4 tonnes, compared to 22.8 tonnes for a Falcon 9 full thrust. Falcon Heavy was designed from the outset to carry humans into space and it would restore the possibility of flying crewed missions to the Moon or Mars.

Following the Falcon 9 CRS-7 failure investigation in 2015, and given a very busy Falcon 9 launch manifest in 2016, the first Falcon Heavy launch is now expected in November 2016.^[11]

History

SpaceX breaking ground at Vandenberg AFB SLC-4E for the Falcon Heavy launch pad

At a press conference at the National Press Club in Washington, DC. on 5 April 2011, Elon Musk stated, “Falcon Heavy will carry more payload to orbit or escape velocity than any vehicle in history, apart from the Saturn V moon rocket, which was decommissioned after the Apollo program. This opens a new world of capability for both government and commercial space missions.”^[12]

SpaceX originally announced that the Falcon Heavy demonstration rocket would arrive at its west-coast launch location, Vandenberg Air Force Base, California, before the end of 2012,^[13] with a launch planned for 2013.^[14] After early launches from Vandenberg, the first launch from the Cape Canaveral east coast launch complex was planned for late 2013 or 2014.^[12] By mid-2015, the company modified the planned first launch date to 2016.^[15] Originally, the first launch from the east-coast Cape Canaveral launch complex (Demo flight #2) was planned for 2013, but it is currently scheduled for March 2017 with the STP-2 US Air Force payload.^[16]

While the initial specifications of the new launcher in April 2011 projected LEO payloads of up to 53,000 kilograms (117,000 lb)^[17] and GTO payloads up to 12,000 kilograms (26,000 lb),^[18] later reports in 2011 projected higher payloads beyond low Earth orbit, including 19,000 kilograms (42,000 lb) to geostationary transfer orbit,^[19] 16,000 kilograms (35,000 lb) to translunar trajectory, and 14,000 kilograms (31,000 lb) on a trans-Martian orbit to Mars.^[13][20]

By late 2013, SpaceX raised the projected GTO payload for Falcon Heavy to up to 21,200 kilograms (46,700 lb).^[21]

The Falcon Heavy falls into the "super heavy-lift" range of launch systems under the classification system used by a NASA human spaceflight review panel.^[22] SpaceX states that the Falcon Heavy will be able to deliver more usable payload to orbit than any launch vehicle since the Saturn V (1967–1973);^[3]

SpaceX announced a number of changes to the Falcon Heavy rocket in 2015, worked in parallel to the upgrade of the Falcon 9 v1.1 launch vehicle as well.^[23]

The new Falcon Heavy design will utilize as the two side cores the same core as the Falcon 9 full thrust, while the center core of the Falcon Heavy will be a core with the original Falcon 9 v1.1 dimensions and structure. Design changes to the Falcon Heavy side cores will include a new propellant mix, changes to the launch vehicle thrust structure, a higher-performance engine—the Merlin 1D has completed a substantive round of additional qualification testing since it was initially used in late 2013 on the initial Falcon 9 v1.1 missions—and several size and volume changes to the first stage and second stage propellant tanks.^[23]

Changes will also be made to the Falcon Heavy second stage, but as of mid-March 2015, public sources regarding second stage changes have only been explicit about changes to the Falcon 9 v1.1 second stage.^[24]

In April 2015, SpaceX sent the "U.S. Air Force an updated letter of intent April 14 outlining a certification process for its Falcon Heavy rocket to launch national security satellites." The process includes three successful flights of the Falcon Heavy including two consecutive successful flights, and states that Falcon Heavy can be ready to fly national security payloads by 2017. As of April 2015, the SpaceX manifest has five Falcon Heavy launches listed, but does not show specific dates.^[25]

By September 2015, and after the failure of Falcon 9 Flight 19 in June 2015, SpaceX rescheduled the maiden Falcon Heavy flight for April/May 2016,^[26] but by February 2016 had moved that back to late 2016.^[27]

Design

From left to right, Falcon 1, Falcon 9 v1.0, three versions of Falcon 9 v1.1, and two versions of the Falcon Heavy

The Heavy configuration consists of a standard Falcon 9 with two additional Falcon 9 first stages acting as liquid strap-on boosters,^[10] which is conceptually similar to EELV Delta IV Heavy launcher and proposals for the Atlas V HLV and Russian Angara A5V. Falcon Heavy will be more capable than any other operational rocket, with a payload to low earth orbit of 54,400 kilograms (119,900 lb) and 13,600 kilograms (30,000 lb) tonnes to Mars.^[2] The rocket was designed to meet or exceed all current requirements of human rating. The structural safety margins are 40% above flight loads, higher than the 25% margins of other rockets.^[28]

Falcon Heavy was designed from the outset to carry humans into space and it would restore the possibility of flying crewed missions to the Moon or Mars.^[29] The Falcon Heavy's designed payload capacity, capabilities, and total thrust are equivalent to the Saturn C-3 launch vehicle concept (1960) for the Earth Orbit Rendezvous approach to an American lunar landing.^[30]

First stage

The first stage is powered by three Falcon 9 derived cores, each equipped with nine Merlin 1D engines. The Falcon Heavy has a total sea-level thrust at liftoff of 22,819 kN (5,130,000 lb_f), from the 27 Merlin 1D engines, while thrust rises to 24,681 kN (5,549,000 lb_f) as the craft climbs out of the atmosphere.^[3]

Falcon Heavy had been designed with a unique propellant crossfeed capability, where some of the center core engines are supplied with fuel and oxidizer from the two side cores, up until the side cores are near empty and ready for the first separation event.^[31] This allows engines from all three cores to ignite at launch and operate at full thrust until booster depletion, while still leaving the central core with most of its propellant at booster separation.^[32] The propellant crossfeed system, nicknamed "asparagus staging", comes from a proposed booster design in a book on orbital mechanics by Tom Logsdon. According to the book, an engineer named Ed Keith coined the term "asparagus-stalk booster" for launch vehicles using propellant crossfeed.^[33] Crossfeed however was not implemented, at least in the first Falcon Heavy version.^[34]

All three cores of the Falcon Heavy arrange the engines in a structural form SpaceX calls Octaweb, aimed at streamlining the manufacturing process,^[35] and each core will include four extensible landing legs.^[36] To control the descent of the boosters and center core through the atmosphere, SpaceX uses small grid fins which deploy from the vehicle after separation.^[37] After the side boosters separate, the center engine in each will burn for a few seconds in order to control the booster’s trajectory safely away from the rocket.^[36][38] The legs will then deploy as the boosters turn back to Earth, landing each softly on the ground. The center core will continue to fire until stage separation, after which its legs will deploy and land it back on Earth as well. The landing legs are made of state-of-the-art carbon fiber with aluminum honeycomb. The four legs stow along the sides of each core during liftoff and later extend outward and down for landing. Both the grid fins and the landing legs on the Falcon Heavy are currently undergoing testing on the Falcon 9 launch vehicle, which are intended to be used for vertical landing once the post-mission technology development effort is completed.^[39]

Second stage

The upper stage is powered by a single Merlin 1D engine modified for vacuum operation, with a thrust at of 934 kN (210,000 lb_f), an expansion ratio of 117:1 and a nominal burn time of 397 seconds. For added reliability of restart, the engine has dual redundant pyrophoric igniters (TEA-TEB).^[10]

The interstage, which connects the upper and lower stage for Falcon 9, is a carbon fiber aluminum core composite structure. Stage separation occurs via reusable separation collets and a pneumatic pusher system. The Falcon 9 tank walls and domes are made from aluminium-lithium alloy. SpaceX uses an all-friction stir welded tank. 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 approach reduces manufacturing costs during vehicle production.^[10]

Reusable technology development

Although not a part of the initial Falcon Heavy design, SpaceX is doing parallel development on a reusable rocket launching system that is intended to be extensible to the Falcon Heavy, first to the booster stage and ultimately to the second stage as well.

Early on, SpaceX had expressed hopes that both rocket stages would eventually be reusable.^[40] More recently, in 2011, SpaceX announced a funded development program to build and fly a reusable launch system that will ultimately bring a first stage back to the launch site in minutes — and a second stage back to the launch pad, following orbital realignment with the launch site and atmospheric reentry, in up to 24 hours — with both stages designed to be available for reuse within "single-digit hours" after return.^[41]

The reusable launch system technology is under consideration for both the Falcon 9 and the Falcon Heavy. It is particularly well suited to the Falcon Heavy where the two outer cores separate from the rocket much earlier in the flight profile, and are therefore both moving at a slower velocity at the initial separation event.^[41]

As of March 2013, the publicly announced aspects of the SpaceX reusable rocket technology development effort include an active test campaign of the low-altitude, low-speed Grasshopper vertical takeoff, vertical landing (VTVL) technology demonstrator rocket,^[42][43] and a high-altitude, high-speed Falcon 9 post-mission booster-return test campaign where—beginning in late 2013, with the sixth overall flight of Falcon 9—every Falcon 9 first stage which was instrumented and equipped as a controlled descent test vehicle to accomplish propulsive-return over-water tests.^[39]

SpaceX has indicated that the Falcon Heavy payload performance to geosynchronous transfer orbit (GTO) will be reduced due to the addition of the reusable technology, but would fly at much lower launch price. With full reusability on all three booster cores, GTO payload will be 7,000 kg (15,000 lb). If only the two outside cores fly as reusable cores while the center core is expendable, GTO payload would be approximately 14,000 kg (31,000 lb).^[44] "Falcon 9 will do satellites up to roughly 3.5 tonnes, with full reusability of the boost stage, and Falcon Heavy will do satellites up to 7 tonnes with full reusability of the all three boost stages," [Musk] said, referring to the three Falcon 9 booster cores that will comprise the Falcon Heavy's first stage. He also said Falcon Heavy could double its payload performance to GTO "if, for example, we went expendable on the center core."

Pricing and development funding

At an appearance in May 2004 before the United States Senate Committee on Commerce, Science, and Transportation, Elon Musk testified, "Long term plans call for development of a heavy lift product and even a super-heavy, if there is customer demand. We expect that each size increase would result in a meaningful decrease in cost per pound to orbit. ... Ultimately, I believe $500 per pound or less is very achievable."^[45] This $500 per pound ($1,100/kg) goal stated by Musk in 2011 is 35% of the cost of the lowest-cost-per-pound LEO-capable launch system in a circa-2000 study: the Zenit, a medium-lift launch vehicle that can carry 14,000 kilograms (30,000 lb) into LEO.^[46]

As of March 2013, Falcon Heavy launch prices are below $1,000 per pound ($2,200/kg) to low-Earth orbit when the launch vehicle is transporting its maximum delivered cargo weight.^[47] The published prices for Falcon Heavy launches have moved some from year to year, with announced prices for the various versions of Falcon Heavy priced at $80–125 million in 2011,^[17] $83–128M in 2012,^[18] $77–135M in 2013,^[48] $85M for up to 6,400 kilograms (14,100 lb) to GTO in 2014, and $90M for up to 8,000 kilograms (18,000 lb) to GTO in 2016 (with no published price for heavier GTO or any LEO payload).^[49] Launch contracts typically reflect launch prices at the time the contract is signed.

SpaceX has claimed the cost of reaching low Earth orbit can be as low as US$1,000/lb if an annual rate of four launches can be sustained, and as of 2011 planned to eventually launch 10 Falcon Heavy and 10 Falcon 9 annually.^[13] A third launch site, intended exclusively for SpaceX private use, is planned at Boca Chica near Brownsville, Texas. SpaceX expects to start construction on the third Falcon Heavy launch facility, after final site selection, no earlier than 2014, with the first launches from the facility no earlier than 2016.^[50] In late 2013, SpaceX had projected Falcon Heavy's inaugural flight to be sometime in 2014, but as of March 2014 expected the first launch to be in 2015^[51] due to limited manufacturing capacity and the need to deliver on the Falcon 9 launch manifest.^[52]

The Falcon Heavy is being developed with private capital. No government financing is being provided for its development.^[53]

By late 2013, SpaceX prices for space launch were already the lowest in the industry.^[54] If SpaceX is able to successfully complete development on its SpaceX reusable rocket technology and return booster stages to the launch pad for reuse—enabling even lower launch prices—a new economically driven Space Age could result.^[53][55]

Testing

As of May 2013, a new, partially underground test stand was being built at the SpaceX Rocket Development and Test Facility in McGregor, Texas specifically to test the triple cores and twenty-seven rocket engines of the Falcon Heavy.^[56]

Scheduled launches and potential payloads

Flight number	Date and time (GMT)	Payload	Customer	Outcome	Remarks
1	November 2016[11]	Falcon Heavy Demo Flight 1	SpaceX
2	March 2017 [57][58]	Falcon Heavy Demo Flight 2, called: STP-2[59]	DoD		The mission will support the U.S. Air Force EELV certification process for the Falcon Heavy.[60] Secondary payloads include LightSail,[61] Prox-1 nanosatellite,[61] GPIM,[62][63][64] the Deep Space Atomic Clock,[65] six COSMIC-2 satellites,[66][67] and the ISAT satellite.[68]
3	2016[26]		Inmarsat
4	2017[60]	Communications satellite[69]	Intelsat[70]		First commercial mission that was booked specifically for Falcon Heavy.[70] First booked launch to a geostationary transfer orbit for Falcon Heavy.[69]
5	April/May 2018	Red Dragon [71]			Planned mission to Mars by a Dragon 2 Spacecraft. Payload and customer unknown.
6	2018[72]	Arabsat 6A	Arabsat		Saudi Arabian communications satellite.

First commercial contract: Intelsat

In May 2012, SpaceX announced that Intelsat had signed the first commercial contract for a Falcon Heavy flight. It was not confirmed when the first Intelsat launch would occur, but the agreement will have SpaceX delivering satellites to geosynchronous transfer orbit.^[69][70]

First DoD contract: USAF

In December 2012, SpaceX announced its first Falcon Heavy launch contract with the United States Department of Defense (DoD). "The United States Air Force Space and Missile Systems Center awarded SpaceX two Evolved Expendable Launch Vehicle (EELV)-class missions" including the Space Test Program 2 (STP-2) mission for Falcon Heavy, scheduled to be launched in March 2017,^[58] and planned to be placed at a near circular orbit at an altitude of ~700 km, with an inclination of 70º.^[73]

The Green Propellant Infusion Mission (GPIM) will be a STP-2 payload; it is a technology demonstrator project partly developed by the US Air Force.^[62][74] Another secondary payload is the miniaturized Deep Space Atomic Clock.^[75]

Solar System transport missions

In 2011, NASA Ames Research Center proposed a Mars mission called Red Dragon, that would use a Falcon Heavy as the launch vehicle and trans-Martian injection vehicle, and the Dragon capsule to enter the Martian atmosphere. The proposed science objectives were to detect biosignatures and to drill 3.3 feet (1.0 m) or so underground, in an effort to sample reservoirs of water ice known to exist under the surface. The mission cost as of 2011 was projected to be less than US$425,000,000, not including the launch cost.^[76] The concept was to be formally proposed in 2012/2013 as a NASA Discovery mission but was not selected.^[77]

Beyond the Red Dragon concept, SpaceX announced in May 2015 that they are positioning Dragon V2 spacecraft variants—in conjunction with the Falcon Heavy launch vehicle—to transport science payloads across much of the solar system, in cislunar and inner solar system regions such as the Moon and Mars as well as to outer solar system destinations such as Jupiter's moon Europa. Details include that SpaceX expects to be able to transport 2,000–4,000 kg (4,400–8,800 lb) to the surface of Mars, including a soft retropropulsive landing using SuperDraco thrusters following a limited atmospheric deceleration. When the destination has no atmosphere, the Dragon variant would dispense with the parachute and heat shield and add additional propellant.^[78]

See also

• Comparison of orbital launch systems
• Comparison of orbital launchers families
• Delta IV Heavy
• List of Falcon 9 and Falcon Heavy launches
• Mars Colonial Transporter
• Saturn C-3
• Space Launch System

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78. Bergin, Chris (2015-05-11). "Falcon Heavy enabler for Dragon solar system explorer". NASASpaceFlight.com. Retrieved 12 May 2015.

External links

• Falcon Heavy official page
• Falcon Heavy flight animation, January 2015.