# US 12,000,361 B2 · Rocket propellant tank arrangement, rocket propulsion unit, and rocket > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,361 B2 - Document ID: US12000361B2 - Status: Granted - Kind: B2 - Application number: 16/477,839 - Filed: 2018-01-11 - Published: 2019-11-28 - Granted: 2024-06-04 - Earliest claimed: 2017-01-13 - Assignees: Orbital Express Launch Limited - Applicants: Orbital Express Launch Limited - Inventors: Jonas Baekby Bjarnoe; Kristian Von Bengtson - Web page: https://patentgrep.com/patent/US12000361B2 ## CPC - F02K 9/605: {Reservoirs} - B64G 1/4022: {Arrangements of tanks in or on spacecraft} - F05D 2250/231: cylindrical - F05D 2250/36: in inner-outer relationship, e.g. shaft-bearing arrangements - F17C 2270/0194: for use under microgravity conditions, e.g. space - F02K: JET-PROPULSION PLANTS (features of jet-propulsion plants common to gas-turbine plants, air intakes or fuel supply control of air-breathing jet-propulsion plants F02C7/00, F02C9/00) - B64G: COSMONAUTICS; VEHICLES OR EQUIPMENT THEREFOR - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - F17C: VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES (storing fluids in natural or artificial cavities or chambers in the earth B65G5/00; construction or assembling of bulk storage containers employing civil-engineering techniques E04H7/00; variable-capacity gas-holders F17B; liquefaction or refrigeration machines, plants, or systems F25) ## Abstract A rocket propellant tank arrangement (40) for storing fuel and oxidizer for launching a rocket includes an oxygen tank (42) for storing liquid oxygen and a fuel tank (52) for storing liquid fuel, wherein the fuel tank is at least partially arranged within the oxygen tank. ## Claims ### Claim 1 A method of carrying propellant in a rocket and of supplying propellant to an engine of the rocket, comprising: carrying liquid oxygen in an oxygen tank; carrying liquid fuel in a fuel tank, with the fuel tank having a fuel tank wall, with the fuel tank being at least partially arranged within the oxygen tank and with the liquid fuel being one of liquid propane, liquid propene, and liquid propylene, wherein an inner surface of the fuel tank wall is in fluid communication with the fuel in the fuel tank and an outer surface of the fuel tank wall is in fluid communication with the oxygen in the oxygen tank; wherein the fuel tank has a generally cylindrical shape, with the fuel tank wall being generally cylindrical, and wherein the oxygen tank has a generally hollow cylindrical shape, formed between the generally cylindrical fuel tank wall and a generally cylindrical oxygen tank wall, and wherein the fuel tank comprises generally disk-shaped fuel tank caps at its top and bottom ends and wherein the oxygen tank comprises annular oxygen tank caps at its top and bottom ends; jointly controlling a liquid oxygen temperature of the liquid oxygen and a liquid fuel temperature of the liquid fuel, with the fuel tank wall allowing for mutual cooling of the liquid oxygen and the liquid fuel; and supplying the liquid oxygen and the liquid fuel via short range supply lines from a lower portion of the oxygen tank and a lower portion of the fuel tank to the engine, which is arranged below the oxygen tank and the fuel tank. ### Claim 2 (depends on 1) The method of claim 1, wherein a plurality of fuel tank fixation elements are arranged between the fuel tank wall and the oxygen tank wall. ### Claim 3 (depends on 2) The method of claim 2, wherein the plurality of fuel tank fixation elements are a plurality of fixation fins. ### Claim 4 (depends on 1) The method of claim 1, wherein the fuel tank wall is made of aluminum, steel, carbon fiber based composites or composite overwrap aluminum. ### Claim 5 (depends on 1) The method of claim 1, wherein the fuel tank wall is made of austenitic stainless steel. ### Claim 6 (depends on 1) The method of claim 1, wherein the fuel tank wall has a thickness of 0.1 mm to 15 mm. ### Claim 7 (depends on 1) The method of claim 1, wherein the fuel tank wall has a thickness of 0.5 mm to 10 mm. ### Claim 8 (depends on 1) The method of claim 1, wherein the fuel tank wall has a thickness of 1 mm to 5 mm. ### Claim 9 (depends on 1) The method of claim 1, wherein the fuel tank wall is free of insulating material. ### Claim 10 (depends on 1) The method of claim 1, wherein the oxygen tank has an oxygen tank elongation, the fuel tank has a fuel tank elongation, and the oxygen tank elongation is between 80% and 120% of the fuel tank elongation. ### Claim 11 (depends on 1) The method of claim 1, wherein the oxygen tank has an oxygen tank elongation, the fuel tank has a fuel tank elongation, and the oxygen tank elongation is between 90% and 110% of the fuel tank elongation. ### Claim 12 (depends on 1) The method of claim 1, wherein the fuel tank is substantially entirely enclosed by the oxygen tank. ### Claim 13 (depends on 1) The method of claim 1, wherein the oxygen tank is configured to store cryogenic liquid oxygen and the fuel tank is configured to store cryogenic liquid propane. ### Claim 14 (depends on 1) The method of claim 1, wherein the oxygen tank is configured to store cryogenic liquid oxygen or the fuel tank is configured to store cryogenic liquid propane. ### Claim 15 (depends on 1) The method of claim 1, further comprising: receiving the liquid oxygen and the liquid fuel at a combustion chamber of the engine; and ejecting exhaust gases from the combustion chamber via a nozzle, coupled to the combustion chamber.