T-Mobile US became the second major carrier in the country to team up with Project Loon in Puerto Rico, joining in an unconventional effort to restore internet connectivity on the hurricane-damaged island.

In a blog post, T-Mobile CTO Neville Ray noted the decision to partner with Google’s X lab on Project Loon comes as service restoration efforts for cellular and electricity on the island continue to face “significant challenges”.

Ray reported the operator “left no stone unturned” in its recovery efforts, sending cargo planes and ships full of portable cellular network equipment and generators to the island, along with teams of engineering experts. Partnerships with Project Loon and Vanu, a company which produces solar-power based cellular antenna systems, have also been part of T-Mobile’s effort.

T-Mobile isn’t the only carrier to take this unconventional path to restoring connectivity: AT&T also teamed up with Project Loon, the first major US operator to do so.

In a Twitter post, Google’s X lab indicated customers of both T-Mobile and AT&T can now “access limited internet” through the Project Loon balloon network.

The network uses helium filled balloons flown higher than commercial aircraft to deliver ground-based telecoms coverage across a wide geographic area.

Ray said T-Mobile recovered more than 80 per cent of its pre-hurricane outdoor signal in Puerto Rico.

The latest Federal Communication Commission recovery report, dated 29 October, noted 64 per cent of the population in Puerto Rico is now covered with wireless connectivity, though a little more than 57 per cent of cell sites on the island remain out of service.

Notably, the FCC reported no single county in Puerto Rico has 100 per cent of its cell sites down for the first time since hurricane Maria made landfall in September.