SEA06IA105
2006-05-17 · Portland, Oregon, United States · None · 1 aircraft · Status: Completed
Airport PDX
Aircraft involved
Probable cause & findings
The inadvertent deployment of the off-wing escape slide due to the inadequate latching of the slide compartment door following access by maintenance personnel.
Factual narrative
On May 17, 2006, about 0908 Pacific daylight time, a Boeing 757-222 (B-757), N506UA, owned and operated by United Airlines, returned for landing shortly after takeoff from the Portland International Airport, Portland, Oregon, subsequent to an engine indication and crew alerting system (EICAS) advisory message indicating the left off-wing escape slide door was open. The flight was being conducted under Title 14, CFR Part 121, as a scheduled domestic passenger flight, operated by United Airlines, Inc., as Flight 364. There were no injuries to the two pilots, five flight attendants, or the 182 passengers aboard. Visual meteorological conditions prevailed, and an instrument rules flight plan had been filed for the flight to Denver, Colorado. Personnel from United Airlines reported that while climbing through 900 feet mean sea level (msl), the flight crew received a left off-wing escape slide door EICAS message and elected to return to the airport. The crew reported that there were no adverse control problems and the airplane landed at the departure airport without further incident. Post landing examination of the airplane by personnel from United Airlines and the Federal Aviation Administration revealed that the left off-wing escape slide had deployed, without inflating, and was observed hanging from the aircraft's fuselage. Further examination by United maintenance personnel revealed that the slide carrier tray assembly had rotated out, to the open position. The off-wing slide compartment, door and operating latch mechanism were inspected by United maintenance personnel and no discrepancies were noted. Additional examination of the off-wing escape slide assembly by personnel from Boeing engineering revealed no evidence of mechanical malfunction with the system. Maintenance records indicated that on May 15, 2006, (four flights before the slide deployment) the off-wing escape slide pack was replaced in accordance with routine scheduled maintenance intervals for the assembly. The maintenance was completed, and inspected, by United Airlines personnel at a maintenance facility in Chicago, Illinois. A post incident Maintenance Investigation report submitted to the NTSB by United Airlines indicated that the inadvertent deployment of the off-wing slide assembly was the result of the carrier tray not being locked in the stowed position. Post landing examination of the airplane by personnel from United Airlines and the Federal Aviation Administration revealed that the left off-wing escape slide had deployed, without inflating, and was observed hanging from the aircraft's fuselage. Further examination by United maintenance personnel revealed that the slide carrier tray assembly had rotated out to the open position. The off-wing slide compartment, door and operating latch mechanism were inspected by United maintenance personnel and no discrepancies were noted. Additional examination of the off-wing escape slide assembly by personnel from Boeing engineering revealed no evidence of mechanical malfunction with the system. Maintenance records indicated that on May 15, 2006, (four flights before the slide deployment) the off-wing escape slide pack was replaced in accordance with routine scheduled maintenance intervals for the assembly. The maintenance was completed, and inspected, by United Airlines personnel at a maintenance facility in Chicago, Illinois. A post incident Maintenance Investigation report submitted to the NTSB by United Airlines indicated that the inadvertent deployment of the off-wing slide assembly was the result of the carrier tray not being locked in the stowed position. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12
Verbatim from NTSB's published report. Source file
NTSB_2006_SEA06IA105.txt.
Findings + structured fields enriched from FAA avall.mdb.
Full investigation docket on
data.ntsb.gov ↗.
Search this event elsewhere
External sources are reported, not agency: signal that something happened, not fact about what happened.
- TallyAero Live Wire Aviation press
- NTSB CAROL Agency ↗
- NTSB Docket Agency ↗
- Aviation Safety Network Aviation press ↗
- Kathryn's Report Aviation press ↗
- Aviation Herald Aviation press ↗
- AVweb Aviation press ↗
- Pilots of America Community ↗
- Reddit /r/flying Community ↗
- FlightAware Aviation press ↗
- AOPA accident database Aviation press ↗
- Google News News ↗
- DuckDuckGo News ↗
Related research
Matched on aircraft type or causal vocabulary (maintenance). All research papers
- Embry-Riddle Scholarly Commons 2026 · Journal article (IJAAA) From Reactive to Predictive: A hybrid Trust-Mediated Adoption Framework for Data-Driven Maintenance in Distributed-Authority Aviation Environments
Modern aviation maintenance operates within increasingly data-intensive technological environments, yet the operational integration of predictive maintenance into routine decision-making remains incon…
- Semantic Scholar 2026 · Article (Reliability Engineering & System Safety) Understanding human error in military aviation maintenance: The role of Performance shaping factors, cognitive workload and error orientation
- Semantic Scholar 2025 · Article (Applied Sciences) Decision-Making Framework for Aviation Safety in Predictive Maintenance Strategies
The implementation of predictive maintenance (PM) in aviation presents unique challenges due to strict safety requirements, complex operational environments, and regulatory constraints.
- Semantic Scholar 2024 · Article (Defence Science Journal) Modelling of Human Factors in Aviation Maintenance Using HFACS ME Human Factors Analysis and Classification System Maintenance Extension and Bayesian Network
Aircraft maintenance is a complex task involving a skilled human workforce, spare parts, and various other resources. Human factors are an inherent element of the human workforce.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER) A New Trajectory in UAV Safety: Leveraging Reinforcement Learning for Distance Maintenance Under Wind Variations
In the field of aviation, safety is a critical cornerstone, and the operation of Unmanned Aerial Vehicle (UAV) systems is deeply connected with this principle.
- Embry-Riddle Scholarly Commons 2024 · Journal article (JAAER) Low-Resource Automatic Speech Recognition Domain Adaptation – A Case-Study in Aviation Maintenance
With timeliness and efficiency being critical in the aviation maintenance industry, the need has been growing for smart technological solutions that optimize and streamline the different underlying ta…