(Reuters) -Firefly Aerospace on Tuesday said it has received clearance from the Federal Aviation Administration to resume Alpha rocket launches, after a technical issue led to a failure in April.

Shares of the company were up nearly 5% in extended trading.

The Alpha rocket suffered a technical problem while ascending on its sixth flight, causing a Lockheed Martin satellite it was supposed to place into orbit to crash into the Pacific Ocean.

The space tech firm said it conducted an independent review into the incident, along with the FAA's investigation, adding "The findings confirmed Firefly's flight safety system performed nominally through all phases of flight...and the launch posed no risk to public safety."

Alpha's upper rocket body fired for several minutes and ascended an altitude of 320 km (198.84 miles), but failed to reach its intended orbit and was pulled back into the atmosphere, it said.

With the steps to address the issue put in place, Firefly said it is now working to determine the next available launch window for Alpha Flight 7.

Since 2021, four out of six Alpha flights have failed, including the mishap in April. This mission was the first under an agreement between Firefly and Lockheed for up to 25 flights through 2029.

Firefly secured a valuation of $9.84 billion after its shares surged 55.6% in their Nasdaq debut earlier in August, as investors continue to pour capital into companies aiding expansion of the U.S. space and defense program.