Rocket Lab (RKLB) stock tumbled as much as 14% on Thursday after the space company said the first launch of Neutron, its reusable medium-lift rocket, slipped to 2027.

The stock ended Thursday’s session down 6.6%.

Rocket Lab had targeted the fourth quarter of 2026 for Neutron’s debut. CEO Peter Beck blamed manufacturing issues in the forward propellant dome on the rocket’s first stage.

“They don’t necessarily mean that the dome would fail on flight, but our practice is to proceed only when we believe the system has the appropriate margins,” Beck said in a video update, according to Stocktwits. “Possible success isn’t our standard.”

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55.25 -3.93 (-6.64%)

At close: October 15 at 4:00:00 PM EDT

55.57 +0.32 (+0.58%)

Overnight: 9:36:04 PM EDT

Beck said the company has identified manufacturing fixes and expects to finish assembling the first stage within the quarter, when it will be in a better position to announce a launch date. He also pointed to strong demand and upcoming contract announcements.

Neutron is central to Rocket Lab’s effort to compete for larger missions in a market dominated by SpaceX’s (SPCX) Falcon 9. Its schedule has slipped before: Rocket Lab unveiled the rocket in 2021 with a 2024 first-flight target, then moved it to mid-2025 and then to 2026. A first-stage tank ruptured during testing in January.

The plunge came after a 7.9% drop in Wednesday’s regular session, before Rocket Lab released the update at 4:40 p.m. ET.

If Thursday’s drop holds through the close, it would be Rocket Lab’s lowest close since December 2025. The stock is down around 25% this year and about 65% below its 52-week high of $151, set in May.

RocketLab CEO, Peter Beck poses for a portrait at the company's Auckland headquarters on June 10, 2015 in Auckland, New Zealand. (Photo by Phil Walter/Getty Images) RocketLab CEO Peter Beck poses for a portrait at the company’s headquarters on June 10, 2015, in Auckland, New Zealand. (Phil Walter/Getty Images) ยท Phil Walter via Getty Images

Space stocks were already under pressure. AST SpaceMobile (ASTS) fell 10% Wednesday after Piper Sandler cut its price target to $54, citing competition from SpaceX.

Rocket Lab is also working to close its deal for satellite operator Iridium (IRDM).

Cantor Fitzgerald kept its Overweight rating and $122 price target on Rocket Lab after the update, according to Yahoo Finance analyst data.

Internal AI tools helped analyze interview transcripts, research, and draft this post. Humans reviewed, edited, and fact-checked this post before publication.

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