More than three weeks after Hurricane Maria made landfall in Puerto Rico, much of the island remains without access to cell phone service and electricity. In addition to taking dozens of lives, the storm’s 175–kilometer per hour winds, heavy rainfall and flooding destroyed most cell towers and brought down the power grid entirely. Progress to restore these essential services has been slow, given the damage to the island’s infrastructure on the ground. Some relief could be on the way from above, however, in the form of massive, translucent plastic balloons. Launched by Alphabet—Google’s parent company—the balloons could create a network to restore wireless communications for most of the island’s 3.4 million residents.

The floating orbs—which look and move like jellyfish drifting in Earth’s stratosphere—are part of Project Loon, Alphabet’s experimental effort to deliver wireless services to unserved or underserved areas around the world. Puerto Rico will be Project Loon’s biggest challenge since Alphabet’s X (previously known as Google X) officially launched the effort in 2013. X’s plan is to float the solar-powered, helium-filled balloons about 19 kilometers above Puerto Rico and the U.S. Virgin Islands for up to six months, creating a wireless network on the ground covering nearly 7,800 square kilometers. (The island itself is just over 9,100 square kilometers.) The balloons can stay aloft in the stratosphere for 100 days or more at a time, according to the company. They change position by navigating the stratosphere’s well-charted wind currents.

It is unclear when the balloons might arrive, but the U.S. Federal Communications Commission (FCC) granted Alphabet an experimental license (pdf) on October 7 to deploy 30 of them. Project Loon is now looking to collaborate with local telecom providers in Puerto Rico, which could install small base stations called microcells on lampposts, buildings and other locations where there is a clear line of sight with the sky. Cell phones would communicate with the microcells, which in turn would relay those communications to the network of balloons. Each balloon has two main radio transceivers—one serves as a 4G LTE cellular base station and the other acts a high-speed link that transfers data onto laser signals that are beamed among the balloons. The transceivers essentially transmit connectivity from ground stations, across balloons and back down to users’ phones. The signals will be sent over the 900-megahertz frequency band, which the local telecom companies will allow Project Loon to access.

Signals in the 900-MHz band are relatively low frequency, which means they are very reliable when traveling in a straight line through the atmosphere between transmitting and receiving antennas. On the downside, “a few 900-MHz links aren’t going to be enough to provide high-speed connectivity to a whole island,” says Aditya Dhananjay, a postdoc at New York University’s Tandon School of Engineering. However, “it’s more than enough spectrum to connect Puerto Rico to the rest of the world for voice calls and text messaging, but you won’t be able to stream YouTube videos,” adds Dhananjay, who is not involved with Project Loon.

On the Ground

Help cannot come soon enough for Puerto Rico’s residents, who have been scrambling to find cell service to communicate with one another and with family and friends living off the island. Cell networks have been “fairly functional” in the cities of San Juan [in the north] and Guaynabo to the south, says Giovanni Collazo, an app developer living in San Juan. Calls and SMS work most of the time through his service provider—AT&T—but data service is very limited, slow and “fails all the time.” He recently bought a prepaid SIM card for internet access. (A SIM card is an integrated circuit containing unique information that identifies it to a specific mobile network.) “The plan came with 10 [gigabytes] of data, but I’ve been using it a lot more than that,” he says. “I’m using one of my test devices as a wi-fi hot spot. As long as Claro [Telecom] is working in San Juan, I’m able to connect. Another thing is that we don’t have power, so keeping equipment charged is an issue.”

The situation on other parts of the island is much worse. “During the weekend I visited Caguas, Cayey, Aibonito, Barranquitas and Naranjito, and there’s no signal” in those cities, he says. “In most areas not even land lines are working. At one of the stops we saw business owners using satellite phones. As you drive from San Juan to Guaynabo you can see hundreds of cars parked [on] the shoulders of the highway, as people use their phones to contact loved ones and communicate with others on the island and outside [of it],” he notes. “People are finding places where there’s good or at least some reception and are going there to use their devices.” As word spreads about the best places to get reception, people drive to those areas from rural parts of the island. He adds: “The telcos have started putting up signs around Guaynabo and San Juan in places where they have coverage so people can stop there and use their services.”

Collazo has another way to gauge wireless service on the island. He runs a start-up called Alias Payments and has created an app—Gasolina Movil—that allows customers to pay for gas at the pump using their smartphones. “In the past few days we’ve started seeing transactions as stations in the metro area have gone back to normal, and some of them have internet access,” he says. “Our customers are using microwave antennas to get online in most cases since [cable provider] Liberty and Claro have very limited wired service.”

Local television and—more importantly, given the power shortage—radio stations have been talking about Project Loon, so there is some awareness on the island that the technology is coming. “Still, people don’t know when and how it’s going to work,” Collazo says. “Everyone I know and who is involved in one way or another in the tech scene is very excited about it. Everyone agrees the restoring comms is a priority to first enable emergency services, facilitate aid delivery logistics—there are a lot of new truckers without GPS—mobilize politically and, finally, try to restore business like mine.”

Up in the Air

X spokesperson Libby Leahy released a statement saying, “We’re grateful for the support of the FCC and the Puerto Rican authorities as we work hard to see if it’s possible to use Loon balloons to bring emergency connectivity to the island during this time of need. To deliver signal to people’s devices, Loon needs be integrated with a telco partner’s network—the balloons can’t do it alone. We’ve been making solid progress on this next step and would like to thank everyone who’s been lending a hand.”

Other large tech companies have also promised to help Puerto Rico. Facebook CEO Mark Zuckerberg announced in late September the social media giant would send a “connectivity team” to help restore communications on the island. And Tesla CEO Elon Musk tweeted last week that he wants to talk with Puerto Rico’s governor about deploying Tesla’s solar-charged batteries to restore power on the island.

X has tested Project Loon successfully over New Zealand and Peru in recent years. There is one obstacle that could deflate the project, however. Space Data Corp., a company that makes wireless communications technology for use in balloons, sued X and Alphabet last year. Space Data claims the project infringes on two of the company’s patents related to creating airborne networks. The company recently won a motion forcing Alphabet to share technical data on Project Loon to see where it might be infringing on Space Data’s patents and could file an injunction calling for Alphabet to stop using any of its infringing technology until the case is decided, Wired reported in July. Alphabet’s X did not respond to requests for comment on Project Loon. Given the trial is currently scheduled for summer 2019, an injunction would be a major setback to Puerto Rico.