The Future of Falcon Heavy: Will It Be Modernized or Replaced?

No plans exist for enhancing SpaceX's Falcon Heavy in significant ways as of now. While the company envisions minor improvements, such as adding a second hydraulic pump to avoid single-point-of-failure issues seen in the past, these tweaks are not likely to revolutionize the design significantly. Instead, the focus remains on getting the most out of the current fleet of Falcon 9 Block 5 rockets and Falcon Heavy's reusable components.

Ace of All Capabilities

What makes the Falcon Heavy stand out is its capability to lift huge payloads into Low Earth Orbit (LEO) with remarkable efficiency. It can haul up to 28 metric tonnes, outperforming the Delta IV Heavy (DIVH), which can lift a maximum of 22 metric tonnes into orbit. What truly sets the Falcon Heavy apart, however, is its ability to deliver payloads to the Moon or Mars, something the DIVH can't match due to its higher efficiency second stage using Hydrolox (Hydrogen/Oxygen) engines.

Sudden Lunar Mission Plans

Recent developments, such as NASA's May 17, 2019 contract with SpaceX for research on a lunar landing mission, pose a new opportunity. This contract may see SpaceX look beyond its current configurations for the Falcon Heavy. While the current Falcon Heavy's second stage cannot be used for lunar missions due to efficiency limitations, potential upgrades are on the horizon.

New Engine Technologies

Sparking discussion is the possibility of using SpaceX's new Raptor engine, optimized for vacuum conditions, or even mounting a Delta Cryogenic Second Stage atop the Falcon Heavy first stage. This hybrid approach would bring the Falcon Heavy within 2 metric tons of the lifting capacity of the Space Launch System (SLS) Block 1, compellingly reducing the need for expensive and underperforming expendable launch systems.

Future Designs and Replacements

A more radical redesign could include stretching the fairing. Presently, the Falcon Heavy uses a 5-meter fairing, significantly limiting cargo size compared to 7-meter wide Delta and Atlas rockets. SpaceX does offer the option of a larger fairing for an additional 20-30 million dollars, suggesting strong interest from customers.

The most compelling reason for no significant upgrades is the advent of Starship/Super Heavy, a new generation of reusable spacecraft. Starship, with its 100-tonne payload capacity and potentially 10 times the reusability, renders the Falcon Heavy obsolete. The high efficiency and low launch costs of Starship make it the superior choice for future missions.

While there are ongoing discussions and potential for minor improvements, the primary focus for SpaceX is on leveraging and upgrading the Falcon 9 Block 5 and the future of Starship. The Falcon Heavy's unique capabilities and its crucial role in SpaceX’s mission to explore deep space may see short-lived improvements, but the overarching goal remains the transition to more advanced and efficient systems.