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Message: <blockquote data-quote="hrm" data-source="post: 30790250" data-attributes="member: 88125">Saw this in FB. AAIB - India preliminary report findings.Flight: AI-171 | Aircraft: Boeing 787-8 | Date: June 25, 2025 | Route: Ahmedabad (VAAH) → London Heathrow (EGLL)Crash Site: ~1.2 km from VAAH Runway 23, post-V1 and rotation.<img src="https://static.xx.fbcdn.net/images/emoji.php/v9/tb9/1/16/1f6e0.png" alt="🛠️" class="fr-fic fr-dii fr-draggable " style="" />  AAIB Preliminary Report Highlights1. Primary Cause – Electrical Power Transfer Interruption (PTI) During Rotation• During transition from ground to airborne electrical configuration, the aircraft experienced a cascading dual-engine FADEC (Full Authority Digital Engine Control) failure.• Root cause: Uncommanded bus transfer failure due to arcing in the main power relay box (PRB-A), traced to water ingress during pre-flight GPU disconnection in heavy rain.• This led to loss of electronic engine control at rotation, resulting in both GEnx engines rolling back to ground idle within 4–5 seconds.2. Flight Data Record Timeline • +0:11 sec: Nose gear lifts off. • +0:13 sec: Sudden engine rollback begins. Thrust reduces from 92% N1 to <27% within 3 seconds. • +0:16 sec: Master caution + ENG FAIL L/R warnings. FO calls, “Both engines dropping!” • +0:20 sec: Autopilot and flight control reverts to Direct Mode. Pitch up attitude peaks at 18°. • +0:25 sec: Aircraft stalls at 186 ft AGL. • +0:30 sec: Full aerodynamic stall; nose drops rapidly. • +0:38 sec: Ground impact at 54° nose-down attitude, 174 knots.Contributing Factors • Environmental Conditions: • Torrential rain during pushback. • Moisture intrusion into PRB-A connector (P/N: HLN8471) — a known corrosion-risk component. • Latent Maintenance Issue: • Power transfer relay unit showed signs of thermal damage in a previous MEL deferral 2 weeks prior. • No replacement had been conducted; aircraft was cleared under repetitive deferral. • Design Oversight: • Boeing 787 has no physical engine control backup (i.e., no direct mechanical linkage in FADEC loss scenario). • Loss of power supply to both EEC channels resulted in engine “freeze” at ground idle instead of flameout. • Flight Crew Response: • Attempted engine relight sequence not completed before stall onset. • Emergency power selector not activated — possibly due to confusion from multiple ECAM warnings.<hr />[USER=562115]@imhotep[/USER]  what do you think? Is that plausible?------ Post added on [DATETIME="UT"]1750221352[/DATETIME]</blockquote>

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