Lessons from DARPA’s Gremlins and NASA’s Space Launch System

I don’t want to jinx things, but as I write this in late March, there is no burning issue in the news right now tied to our cover story about space debris. That said, the topic is always timely, and optimally, it won’t take a calamity for spacefaring nations to at last stop creating space debris and figure out how to clean up the mess left so far.

Turning to our story about DARPA’s Gremlins program, the Dynetics concept for releasing drones from cargo aircraft and recovering them in midair brings to mind the war in Ukraine. Recovering and refueling drones safely away from the battlefield would be a tremendous advantage. As valuable a weapon as Ukraine’s armed and camera-equipped Bayraktar TB2 drones have reportedly been, these aircraft look vulnerable with their advertised top speed of 220 kilometers per hour and their wheeled landing and takeoffs. Russian forces might not yet know how to knock the TB2s out of the sky or destroy them on the ground, but they could well figure it out. Ukraine only has perhaps 20 of them, according to media reports, and each one must be precious to troops and civilians. If the Gremlins technology were ready — and as our story indicates, it is not — some drones such as the TB2s could be operated directly by troops, but others could be released and recovered from the relative sanctuary of western Ukraine to provide intelligence and strike targets.

Let me switch topics entirely. The rollout of NASA’s first Space Launch System rocket was goosebump-raising for many. Now that this program is getting on track, my hope is that NASA will reinvigorate research on advanced space launch propulsion. The agency abandoned much of that work in the 1990s, and it cancelled the X-33 reusable launch vehicle program without flying the vehicle and its linear aerospike engines.

Some research is going on toward revolutionary propulsion in the commercial sector, but the payoff from such technologies is so far in the future that  companies, with their focus on near-term profits, might not be able to sustain the research and achieve the kind of rollout we saw with SLS.

Will SpaceX’s Starship stack solve the problem when it launches to orbit perhaps in May? I doubt it. Reusing Starship’s Super Heavy booster and the Starship passenger and cargo spacecraft atop would be a step in the right direction, but they’re unlikely to make “space travel like air travel,” which is the goal stated by Elon Musk. Super Heavy will be propelled by some 33 Raptor engines that will burn oxygen and methane. It will land upright to be readied for its next flight, but that many engines would seem to raise the odds of encountering significant maintenance issues between flights.

If the United States wants to help the commercial sector open the space frontier, NASA must serve as an R&D engine.

Related Topics


About Ben Iannotta

Ben keeps the magazine and its news coverage on the cutting edge of journalism. He began working for the magazine in the 1990s as a freelance contributor and became editor-in-chief in 2013. He was editor of C4ISR Journal and has written for Air & Space Smithsonian, New Scientist, Popular Mechanics, Reuters and Space News.

Lessons from DARPA’s Gremlins and NASA’s Space Launch System