Falcon Heavy

Falcon Heavy (FH), previously known as the Falcon 9 Heavy, is a spaceflight launch system being designed and manufactured by SpaceX. Both stages of the two-stage-to-orbit vehicle use liquid oxygen (LOX) and rocket-grade kerosene (RP-1) propellants, on a SpaceX-designed rocket engine, the Merlin 1D. Multiple variants are planned with payloads of 53,000 kilograms (120,000 lb) to low Earth orbit (LEO),^[4] and 12,000 kilograms (26,000 lb) to geostationary transfer orbit (GTO).^[5]

The payload to LEO falls into the category that a classification system used by a NASA review panel for plans for human spaceflight calls the super heavy lift range of launch systems.^[6]

Design[edit]

From left to right, Falcon 1, Falcon 9 v1.0, Falcon 9 v1.1 and Falcon Heavy

The Falcon Heavy configuration consists of a standard Falcon 9 with two additional Falcon 9 first stages acting as liquid strap-on boosters,^[7] which is conceptually similar to EELV Delta IV Heavy launcher and proposals for the Atlas V HLV and Russian Angara. Falcon Heavy will be more capable than any other operational rocket, with a payload to low earth orbit of 53,000 kilograms (120,000 lb).^[8] 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.^[9]

The Falcon Heavy's designed payload capacity, capabilities, and total thrust (17,000 kilonewtons (3,800,000 lb_f)) are equivalent to the Saturn C-3 launch vehicle concept (1960) for the Earth Orbit Rendezvous approach to an American lunar landing.^[10]

First stage[edit]

The first stage is powered by three Falcon 9 derived cores, each equipped with 9 Merlin 1D engines. The Merlin 1D is an updated version of the previous Merlin engine that provides a sea level thrust of 620 kN (140,000 lbf),^[11] and a vacuum thrust of 690 kN (155,000 lbf), and is throttleable from 100% to 70%.^[12]

Engines from all three cores ignite at launch, but until fuel runs out in the booster cores, the main core uses little or none of its own propellant. Falcon Heavy is being designed with a unique propellant crossfeed capability, where fuel and oxidizer are fed to power most of the engines on the center core from the two side cores, up until the side cores are near empty and ready for the first separation event.^[13] There are three separation events: the simultaneous separation of the two booster cores followed later by the separation of the main booster core from the second stage. This is akin to a three stage rocket and thus enables greater performance.^[14] Compared to what is thought of as a two and a half stage rocket, like the Delta IV Heavy, the Falcon Heavy central core can operate at full thrust and still be left with a full fuel load after booster separation, as opposed to a partial load.

After the side cores are released, the center engine in each side core will continue to burn for a few seconds in order to control the trajectory of the side booster.^[15]

Second stage[edit]

The upper stage is powered by a single Merlin 1D engine modified for vacuum operation, 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).^[7]

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 aluminum 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.^[7]

Related development[edit]

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.

Early on, SpaceX had expressed hopes that both rocket stages would eventually be reusable.^[16] More recently, in 2011, SpaceX announced a funded development program to build and fly a reusable launch system that will 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.^[17] As of February 2012^[update], design is complete on the system for "bringing the rocket back to launchpad using only thrusters."^[17]

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.^[17]

As of March 2013^[update], the publically 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,.^[18][19] and a high-altitude, high-speed Falcon 9 post-mission booster-return test campaign where—beginning in mid-2013, with the sixth overall flight of Falcon 9—every Falcon 9 first stage will be instrumented and equipped as a controlled descent test vehicle to accomplish propulsive-return over-water tests.^[20]

Launcher versions[edit]

The initial version of the Falcon Heavy will use Falcon 9 v1.1 extended-length stages with Merlin 1D engines.

History[edit]

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

At an appearance in May 2004 before the U.S. 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. "^[24] This $500 per pound goal is approximately half the cost that is currently achievable by the next closest competitor: the Zenit launch vehicle.^[25]

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.”^[26] As of March 2013^[update], Falcon Heavy launch costs are below $1,000 per pound ($2,200/kg) to low-Earth orbit when the launch vehicle is transporting its maximum delivered cargo weight.^[23]

As of April 2011^[update], SpaceX anticipated that the Falcon Heavy demonstration rocket would arrive at SpaceX's west-coast launch location, Vandenberg AFB, California, before the end of 2012,^[27] with a launch planned for 2013.^[8] After early launches from Vandenberg, the first launch from the Cape Canaveral east coast launch complex was planned for late 2013 or 2014.”^[26] By late 2012, the company had modified the planned dates to say that the launch vehicle hardware would arrive in Vandenberg in 2013,^[28] with first launch from the east-coast Cape Canaveral launch complex still planned for 2013 or 2014. 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. SpaceX plans to launch 10 Falcon Heavy and 10 Falcon 9 annually.^[27] A third launch site, intended exclusively for SpaceX private use, is planned, with locations in Texas, Florida, and Georgia under consideration.^[29] A site near Brownsville, Texas is the front runner as of April, 2013, however 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.^[29]

While the official specifications of the new launcher limits LEO payloads to 53,000 kilograms (120,000 lb)^[4] and GTO payloads to 12,000 kilograms (26,000 lb),^[5] reports in 2011 had suggested higher payloads beyond low Earth orbit, including 19,000 kilograms (42,000 lb) to geostationary transfer orbit,^[30] 16,000 kilograms (35,000 lb) to translunar trajectory, and 14,000 kilograms (31,000 lb) on a trans-Martian orbit to Mars.^[27][31]

'Red Dragon' Mars Mission[edit]

As of July 2011^[update], NASA Ames Research Center is developing a concept for a low-cost Mars mission that would use Falcon Heavy as the launch vehicle and trans-Martian injection vehicle, and the Dragon capsule to enter the Martian atmosphere. The concept would be proposed in 2012/2013 as a NASA Discovery mission for launch in 2018 and arrival at Mars several months later. The science objectives of the mission would be to look for evidence of life — detecting "molecules that are proof of life, like DNA or perchlorate reductase ... proof of life through biomolecules. ... Red Dragon would drill 3.3 feet (1.0 m) or so underground, in an effort to sample reservoirs of water ice known to lurk under the red dirt." The mission cost is projected to be less than US$425,000,000, not including the launch cost.^[32]

First commercial contract: Intelsat[edit]

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.^[33][34]

First DoD contract: USAF[edit]

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, initially scheduled to be launched in 2015.^[35][36]

Testing[edit]

A new, partially underground test stand has been built specifically to test the triple cores and twenty seven rocket engines of the Falcon Heavy.^[37]

Launches and scheduled launches[edit]

See also[edit]

• Comparison of orbital launchers families
• Comparison of orbital launch systems
• Saturn C-3
• Jarvis (rocket)
• Criticism of the Space Shuttle program

References[edit]

External links[edit]

• Falcon Heavy official page