A small experimental rocket launched by a Japanese aerospace startup failed shortly after takeoff Saturday when its onboard computer detected an abnormality and shut off the engine. It then crashed into the sea.

The Momo-4 vehicle was Interstellar Technologies Inc.’s fourth rocket designed to carry out experiments, including releasing a heat-resistant paper plane from outer space.

Its predecessor in May became Japan’s first privately funded rocket to reach an apogee of more than 100 kilometers. The launch of the rocket was postponed a week ago due to a technical problem.

The vehicle only reached an altitude of 13 kilometers following the launch at 4:20 p.m., falling into the sea some 9 kilometers (about 5.5. miles) offshore from Taiki, Hokkaido, its test site, Interstellar Technologies said.

The rocket is the same model as Momo-3, measuring about 10 meters long, 50 centimeters in diameter and weighing 1 ton.

After failed attempts in 2017 and 2018, the startup finally found success with its third launch in May, with the rocket reaching an altitude of around 113 km before falling into the Pacific Ocean.

Founded in 2013 by former Livedoor Co. President Takafumi Horie, Interstellar Technologies aims to develop low-cost commercial rockets to carry satellites into space.

Momo-4 was also loaded with a low-frequency sound sensor developed by Kochi University of Technology to observe phenomena associated with natural disasters such as lightning, typhoons and volcanic eruptions, according to the company.