---
type: source
title: "Starship Ship 36 RUD: COPV Root Cause Identified, Corrective Actions Implemented Before IFT-12"
author: "Teslarati / ilovetesla.com / RFSafe"
url: https://www.teslarati.com/spacex-elon-musk-share-insights-starship-ship-36-rud/
date: 2025-06-18
domain: space-development
secondary_domains: []
format: article
status: processed
processed_by: astra
processed_date: 2026-05-09
priority: medium
tags: [starship, ship-36, rud, copv, ground-test, failure-analysis, ift-12, v3, launch-infrastructure]
intake_tier: research-task
extraction_model: "anthropic/claude-sonnet-4.5"
---

## Content

**The incident (June 18, 2025):**
Ship 36 (a Starship upper stage) exploded at 11:02:52 PM CDT during propellant loading for a planned six-engine static fire test at Starbase. The energetic event destroyed Ship 36 completely and caused significant damage to ground support equipment (GSE). No injuries.

**Root cause (identified):**
Most probable root cause: undetectable or under-screened damage to a **Composite Overwrapped Pressure Vessel (COPV)** in Starship's payload bay section.
- COPVs in payload section store gaseous nitrogen for use in the environmental control system
- The damaged COPV failed under propellant loading pressure, causing structural failure of the vehicle
- Subsequent propellant mixing and ignition produced the energetic event (RUD)
- COPV internal damage was "undetectable" with existing inspection methods — systematic screening failure, not individual workmanship defect

**Corrective actions (implemented for subsequent vehicles including IFT-12 Ship 39):**
1. COPVs on upcoming flights will operate at reduced pressure
2. Additional inspections and proof tests added prior to loading reactive propellants
3. Updated COPV acceptance criteria
4. New non-destructive evaluation (NDE) method developed to detect internal COPV damage
5. New external covers added to COPVs during integration — additional protection and visual indication of potential damage

**Significance for IFT-12 (Ship 39, V3):**
Ship 39 (the IFT-12 upper stage) was manufactured after Ship 36's RUD and with the above corrective actions in place. The Ship 36 incident is historical context for IFT-12 preparation — it explains heightened pad safety procedures and the revised trajectory (more southerly, lower debris risk) for IFT-12.

**The April 6, 2026 "RUD" reference:** Some IFT-12 search results referenced an April 6 RUD at Starbase, which may have conflated the Ship 36 incident (June 2025) or referenced a separate incident. The IFT-11 anomaly that triggered the FAA investigation was April 2, 2026 (flight anomaly, not ground incident).

## Agent Notes

**Why this matters:** Understanding the Ship 36 RUD is critical context for IFT-12 risk assessment. The COPV root cause is a systematic screening problem, not a random failure — which means the corrective actions (new NDE method, external covers) should meaningfully reduce recurrence probability for Ship 39. This is relevant to Belief 2 (chemical rockets as bootstrapping tool) — ground test failures are part of the development trajectory.

**What surprised me:** The "undetectable" framing — existing inspection methods couldn't catch the COPV damage. SpaceX had to develop an entirely new non-destructive evaluation method. This suggests deeper systemic risk than a typical workmanship failure, and the corrective action is more comprehensive as a result.

**What I expected but didn't find:** A straightforward manufacturing defect. The COPV failure mode is more subtle — it requires new inspection technology to detect, not just improved manufacturing quality control.

**KB connections:**
- [[reusability without rapid turnaround and minimal refurbishment does not reduce launch costs as the Space Shuttle proved over 30 years]] — ground test failures that delay program timelines contribute to the non-linear relationship between technical progress and cost reduction
- [[Starship achieving routine operations at sub-100 dollars per kg is the single largest enabling condition for the entire space industrial economy]] — Ship 36 RUD delayed V3 development timeline but corrective actions were implemented; IFT-12 Ship 39 is post-corrective
- SpaceX iterative development philosophy: fail fast, identify root cause, fix systematically — Ship 36 → new NDE method → Ship 39 is the iteration cycle

**Extraction hints:**
- Not likely a standalone claim — more relevant as evidence in existing Starship development trajectory claims
- Could enrich the "Starship achieving routine operations" claim with evidence of systematic corrective action culture
- The COPV/NDE story is interesting for manufacturing domain (Astra's broader territory): new inspection methods developed under operational pressure

**Context:** Ship 36 incident occurred June 2025. This predates IFT-12 planning. It caused significant pad damage and delayed V3 production but was addressed before IFT-12 hardware was finalized.

## Curator Notes

PRIMARY CONNECTION: [[Starship achieving routine operations at sub-100 dollars per kg is the single largest enabling condition for the entire space industrial economy]]
WHY ARCHIVED: Historical context for IFT-12 risk assessment — the primary pre-IFT-12 ground failure and its corrective actions are needed for accurate belief calibration on Starship's development trajectory
EXTRACTION HINT: Primarily enrichment evidence for existing claims, not a new claim. The manufacturing/inspection methodology story (new NDE for COPV detection) could interest the manufacturing domain claims if those are ever created
