Why Are Reusable Launch Vehicles Safer Than Expendable Ones?

Diving into the safety and reliability of launch vehicles, a common debate in the aerospace industry is whether reusable or expendable launch vehicles (RLVs or ELVs) are safer. The conventional wisdom suggests that because ELVs fly only once, they are inherently safer. However, this notion is often based on misunderstandings and a lack of comprehensive evidence. Let’s explore the facts and figures that challenge this idea.

ELVs vs. RLVs: Misconceptions vs. Reality

ELVs are typically built with the highest quality standards, and their single-use nature is often cited as a safety advantage. However, reusable launch vehicles (RLVs), particularly those from SpaceX, such as the Falcon-9 and Falcon-Haevy, have a remarkable safety record, overturning these misconceptions.

Facts Over Guesswork

The success record of the SpaceX Falcon-9 and Falcon-Haevy is unparalleled. Both of these RLVs have an impeccable track record of delivering payloads to their intended destinations. In fact, no other rocket system in existence can match their performance.

Success of Falcon Heavy

Falcon Heavy has flown only twice, and both missions were flawless. The rocket successfully delivered its payloads to the correct orbit, showcasing a high degree of reliability.

Performance of Falcon 9

Falcon 9 has an even more impressive record. Over nine years, it has flown 73 missions, completing 70 of them perfectly. The only partial success was the failure of a secondary payload on the CRS-7 mission due to an engine pressure loss.

Total Failures of Falcon 9

The only two total failures of Falcon 9 were the partial failure of CRS-7, where the support strap on the LOX tank broke, leading to a mission failure, and the loss of the Atmos-6 during a pre-launch test due to a manufacturing defect.

First-Time Flights

What’s fascinating is that all of Falcon 9’s failures occurred during the first launch of a new booster. Not a single mission failure has happened on a reused Falcon-9. This highlights the significant advantage of reusing rockets, as the initial test flights can catch manufacturing defects, making future flights safer.

The Space Shuttle

While the Space Shuttle, a semi-reusable system, did have two total failures and a few partial failures over 150 missions, its overall record is still commendable. The safety risk in RLVs is even lower than that of the Space Shuttle.

RLV Safety: The Key to Reliability

Reusable launch vehicles are inherently safer for several reasons. Most of Falcon 9’s failures were due to manufacturing defects, which can be detected and resolved after the first use. This means that after the initial flights, the boosters are less likely to experience the same issues, making them more reliable.

Single-Use Rockets: A Continuous Test Flight

In contrast, ELVs face a new set of challenges with every launch, making them less reliable. Since each mission is effectively a test flight, there is no assurance of consistent performance or safety.

Conclusion: Safety and Reusability

Based on the evidence so far, reusable rockets, including those from SpaceX, are more reliable and safer than their expendable counterparts. The stringent testing and real-world usage of RLVs lead to significant operational efficiencies and safety improvements, making them the preferred choice for modern space missions.