Looking to the future can also often involve looking back, and as we witness an apparent resurgence in the development of increasingly large Space launchers from a number of competing nations, we also see echoes of the past from a time when ‘ultra-heavy’ Space launcher concepts once existed in proposals from the biggest players of the day in the aerospace industry. So let’s for a while blow off the dust from some fascinating rocket designs that would have dwarfed Space X’s current Starship and were each intended to be the Saturn V 2.0…
Nexus
- UNIQUE FEATURE: largest multi-chamber plug nozzle engine seen on any rocket design
- Early 1960s
- Rocket concept devised by team in the Convair Division of General Dynamics, led by German-American rocket propulsion engineer and Space travel visionary Krafft Arnold Ehricke.
- In terms of ‘rocket physique’ the Nexus could be best described as the ‘sumo wrestler’ in our list of biggest rockets!
- Unique rocket design that would have employed an enormous ‘aerospike’ engine (with propellant tapered inwards around a truncated cone-shaped nozzle or ‘plug’ to create a single ‘spike’ exhaust plume.)
- ‘Multi-chamber’ propulsion: provided by numerous spherical liquid oxygen tanks arranged around one enormous squat liquid hydrogen tank housed in the vehicle’s colossal first stage.
- Armagh Planetarium’s famous 12-metre domed theatre would have completely disappeared inside the vehicle’s humongous truncated plug nozzle engine!
The historic dome and 360-degree 95-seat digital theatre of the Armagh Planetarium. Image Credit: Nick Parke
- Would have had 4 ‘control engines’ to help steer the vehicle, located around periphery of rocket’s base in N, S, E, W positions.
- Beside a Saturn-V rocket, the Nexus might have looked not unlike some gigantic 3-tier wedding cake and the Saturn-V like a thin taper candle!
- The auditorium of London’s Royal Albert Hall could just about have stretched around the 61.5-metre-diameter base of the Nexus rocket!
Auditorium of the Royal Albert Hall, London.
Image Credit: petertakacs – Stock.abobe.com
- First stage of the rocket would have been reusable, for its return to Earth the base would rotate upside down with the blunt nose acting as its own enormous heat shield.
- Sheer size of Nexus’ heat shield would be an advantage in slowing it down like its own large ‘air brake’.
- Like Starship’s grid fins, 4 large panels or ‘reaction structure flaps’ would extend out from the sides to maintain orientation of the stage during descent.
- After final deceleration using a huge 160-tonne parachute (in itself heavier than most rockets), retro rockets and touchdown rockets engines would churn up the ocean’s surface to create a softer ‘cushion of steam’ before impact.
- To reinforce the reusable rocket stage for splashdown impact a huge amount of titanium would have been needed, enough to cover 32 tennis courts!
- Tug boats would then tow it back for refurbishment for future Space missions.
- The largest iteration of this rocket, at 135 metres in height, would have been more than twice the height of the Sydney Opera House
Australia’s distinctive 67-metre-tall Opera House, Sydney.
Image Credit: deanbennett / unsplash.com
- Sound of the rocket engine would have been too devastating for humans on land, requiring it to be launched from an offshore platform or island like a ‘Thunderbird’ rocket from Tracy Island (as seen in the iconic 1960’s TV show of the same name).
- Offering 48 million LBF it was estimated that the Nexus’s core engine could single-handedly provide almost 7 times the entire thrust of the Saturn-V rocket!
How To Fly An Entire Moon Base In One Go – Saturn V 2.0 – Convair Nexus
Video Credit: Escape Velocity / YouTube
AMLLV
- UNIQUE FEATURE: largest solid rocket boosters ever seen on any rocket design and greatest payload-lifting power of a chemical rocket
- 1968 NASA-sponsored ultra heavy launcher proposal from Boeing
- AMLLV was the largest iteration of the ‘MLLV’ and stood for Advanced Multi-Purpose Large Launch Vehicle
- Highly modular launch vehicle that could be adapted for a variety of launches and Space missions according to the quantity and size of solid rocket motors (SRMs) and the rocket’s overall height (by stacking additional rocket stages on the core of this already fully-capable ‘Single-Stage-To-Orbit’ launcher).
- At 138 metres tall this substantial vehicle would have been more than twice the height of a Saturn 1B Rocket -(68m tall), and 3 metres taller than the London Eye!
- Like Nexus, the liquid fuel rocket core most likely to have been powered by a multi-chamber plug nozzle engine
Artist’s Impression: An AMLLV at County Hall, London. Image Credit: Nick Parke
- In terms of ‘rocket physique’ the AMLLV could perhaps best be described as the ‘power lifter’ of the bunch as it would have been able to lift a payload mass greater than 4 entire International Space Stations in one spectacular launch!
- This would have greatly reduced cost by removing the need for numerous launches or multiple assembly missions of Space hardware in Earth orbit, even if an expendable vehicle.
- The AMLLV boasts the largest solid fuel boosters ever proposed of any known rocket design (each 9.5m in diameter), until the emergence of Space X’s ‘Super Heavy booster’ of present day (which is 9 metres in diameter).
- This ultra-heavy launcher would therefore have been equivalent to 10 Space X Superheavy boosters standing in a great ring and all attached to an even larger 22m-diameter rocket core rising from the centre!
WOW! Watch SpaceX Catch A Starship Booster In Air – YouTube
Video Credit: @TheLaundPad / YouTube
- AMLLV’s boosters would have been so huge their mere width would have spanned the length of a double-decker bus!
- Construction and launch of this ‘muscular’ Space rocket would needed to have been at an offshore sea platform with parts transported to it by barge as any inland launchpad infra-structure (concrete flame trench etc.) would literally have crumbled from the reverberations of the rocket’s engines, never mind destroying the vehicle itself!
- It was estimated that this incredibly powerful Space rocket would have been able to lift a maximum payload 16 times greater than the Saturn V rocket at 1905 tonnes…
- In its heaviest configuration (with the 10 monstrous ‘strap on’ boosters) the vehicle’s total diameter would have filled St. Peter’s Basilica dome, at 42 metres across, (and stood 2 metres taller than the dome’s highest point)!
St. Peter’s Basilica dome, Rome.
Image Credit: Peter de Vink / pexels.com
- Although at lift-off the ultra-heavy launcher’s engine burn would have boiled any unfortunate sealife in the immediate area, the plentiful water supply of the ocean should have been effective in muffling the tremendous sound and force of all the rocket’s engines at full throttle
Boeing’s 4 Million lbs Payload Rocket (LMLV) Large Multipurpose Launch Vehicle Concept
Video Credit: Hazegrayart / YouTube
Sea Dragon
- UNIQUE FEATURE: largest single-nozzle bell engine
- 1962 highly feasible ultra-heavy rocket concept from the naval captain and visionary rocket engineer at Aerojet, once called ‘American Rocketman’ – Robert Truax.
- Truax previously worked on the Polaris missile and the American Thor rocket and debriefed German rocket engineers such as Werner Von Braun brought to the US during ‘Operation Paperclip’.
- Sea Dragon represented a completely original method for the launch of an enormous Space rocket.
- Truax was something of a revolutionary in his belief that reducing the cost of Space travel was best achieved by making a launcher as simple as possible and much bigger.
- This ultra-heavy launcher would’ve been 150 metres tall and 23 metres wide.
- That’s more than twice the diameter of the Saturn V!
- If upright on land – it would have been more than twice the height of the Taj Mahal!
The iconic 73-metre-tall Taj Mahal, India. Image Credit: buddy sagar / pexels.com
- Instead of a complex pump system across a number of engines just have 1 huge powerful engine.
- Even if this “big dumb booster” were less efficient than a Saturn V launcher, economies of scale would still make it a preferred option to transport larger payloads to Space
- If built, the Sea Dragon would have had the largest bell engine design ever seen on a rocket with a circumference great enough to wrap around a Saturn V rocket!
- Deemed best to launch the rocket not only from the ocean but in the ocean.
- When floating out to sea on its side would have been as long as Vanguard-Class Trident Nuclear submarine.
- Amazingly simple, no launchpad or launch tower needed, vehicle would have been built like a ship in a lagoon and tugged out to sea about 35km from the coast.
- Built on the premise that the large structure and weight of a sea rocket rather like a whale, will be better supported by the superior pressure of water than air pressure while being assembled and tugged to the launch site.
The Biggest Rocket ever Designed? – The Sea Dragon
Video Credit: Curious Droid / YouTube
- A ring of ballast tanks around the base of the rocket would be flooded to sink it engine-first until mostly submerged and ‘standing’ upright in the ocean.
- The water would absorb the tremendous blast at point of ignition while the single huge engine nozzle is submerged in the sea
- The hot gaseous propellant would clear the engine nozzle of water and still cause the rocket to move in the opposite direction, upwards
- Calculated that the huge mound of displaced water that would accompany the rising rocket in the first few seconds of launch would act like a temporary ‘natural launch tower’ providing additional stability as the high-rise-sized vehicle vacates the ocean
- A brief blast of retrorockets from side vents would further aid a stable vertical takeoff
- The rocket’s flames would have been about a mile long!
- Amphibious launch of Truax’s much smaller ‘Sea Horse’ rocket (from a repurposed Corporal missile) showcased the principles of a sea rocket along with the feasibility of underwater engine ignition.
Sea Dragon Launch — Ultimate Rocketry
Video Credit: Nauja diena / For All Mankind / YouTube
Further vehicle development and testing required to bring any of these mighty Space launchers to life was arrested and the projects shelved as a repercussion of reduced NASA funding after the Space Race, quelling all ambitious Space projects in the USA for the foreseeable future.