In September 2023, the Federal Aviation Administration (FAA) proposed a new rule for the disposal of upper stages after commercial launches. In short, for most launches to LEO and GTO, operators will either be required to conduct controlled reentries or move their stage to a higher disposal orbit.
As a researcher who has studied uncontrolled reentries for several years, I was pleased to see the FAA finally address the dangerous abandonment of upper stages. The new rule would reduce the growth in orbital collision risk; currently, there are over 2,000 derelict upper stages in orbit, with a net 36 more added each year.
It would also reduce on-ground casualty risks. With an average mass of over 2,700 kilograms, these stages don’t entirely burn up on reentry. In our research, published in March in the Journal of Space Safety Engineering, my colleagues and I calculated that there’s a 20 to 29% chance someone on the ground will be killed by debris from a reentering upper stage in the next decade.
The United States is a significant contributor to both these orbital and reentry risks; 135 U.S. launches have abandoned upper stages in orbit in the past decade, and two-thirds of them are still up there now.
In a disappointing carve-out, the new FAA rule still allows “smaller” uncontrolled reentries, corresponding to stages under approximately 700 kilograms, up to 25 years after launch. It also permits using certain disposal orbits in MEO and above GEO, in which there are already hundreds of upper stages. Both these disposal options amount to abandonment, and simply kick the can down the road for future generations to deal with. That hasn’t worked out well for us, historically.
As recently as March, debris thought to have originated from a 2,600 kilogram pallet of depleted batteries thrown off the ISS in 2021 reentered the atmosphere, with one two-pound piece tearing through a house in Florida.
Though the debris was not an upper stage, it is clear that our relaxed approach to abandonment needs to change. The FAA should not allow any uncontrolled reentries or upper stage abandonment in Earth orbit.
Industry pushback
The new rule will increase costs for operators, requiring upgrades to engine designs and reserving some fuel for disposal or a controlled reentry burn. But it broadly brings commercial launches into line with the rules that have applied to NASA and Department of Defense launches for well over a decade.
As expected, industry is opposed. In public comments on the new rule, six launch operators including SpaceX, ULA, RocketLab, Blue Origin, Sierra Space and Relativity Space spell out their oppositions.
The most common argument put forward by half of these companies is that the new rule will decrease U.S. competitiveness. The companies also argue that the rules will reduce U.S. leadership in space and cause prohibitive costs. They also question the FAA’s jurisdiction on the matter.
The strongest response comes from SpaceX, which calls for the FAA to withdraw the rule and essentially argues against any restrictions on its activities. Ironically, SpaceX already conducts controlled reentries for many Starlink, U.S. government and DoD launches, and clearly isn’t a stranger to innovation.
Industry reluctance to regulatory change is nothing new. Across all industries, from aviation to automotive, increases in safety often correspond to an increase in costs. We can learn from them.
In the 1980s, the oil tanker industry stymied efforts to require tankers to have double hulls, which decreased leaks and spills compared to single hulls. The strongest argument against this upgrade was the increased construction and operational costs.
After the single-hulled ship Exxon Valdez ran aground in 1989, spilling 11 million gallons of oil into the coast of Alaska, public opinion shifted.
By the end of 1990, the U.S. had amended its Oil Pollution Act, requiring double hulls on all new tankers and phasing out older tankers docking at its ports. Within three years, it had spearheaded the International Maritime Organization to do the same, amending the MARPOL convention.
However, the long transition period allowed by the new rules saw another single-hulled tanker, Erica, break apart and cause a major oil spill off the coast of France in 1999. The MARPOL rules were then tightened again in 2003 and 2005. U.S. leadership and competitiveness were not harmed.
There are two lessons we can learn here.
The first is that rules will certainly be adopted after an upper stage causes a catastrophic collision in orbit or lands on a city. Near misses, such as a Falcon 9 upper stage crashing 50 meters from a house in Brazil in 2022, should be a wake-up call.
The second is that U.S. leadership can lead to a safer world — if it chooses to step up.
Ewan Wright is a PhD candidate at the University of British Columbia, where he is writing a thesis on uncontrolled reentries, and a Junior Fellow of the Outer Space Institute.
Correction (April 16): This article has been updated to reflect that the average spent stage has a mass of over 2,700 kilograms, not 21,700 kilograms. SpaceNews regrets the error.
Tyler Mitchell