LAX91LA038 · Aerostar S-77A
Aerostar S-77A · Accident: airframe, component or system failure during takeoff
From an unrecorded airport to No airport
Event
- NTSB case
- LAX91LA038
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aerostar S-77A
- Aircraft type
- Aerostar S-77
- Category
- Balloon
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N3605T
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo No airport
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Takeoff
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Manufacturer › Acft/equip, inadequate standard/requirement
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
WHILE BOARDING PSNL FOR A LAUNCH, THE BALLOON (BLN) WAS INFLATED & TETHERED TO A VEHICLE WITH A QUICK RELEASE LINE. WINDS AT THE TIME WERE ESTD TO BE ABT 7 KTS & SLIGHTLY GUSTY. DRG THE LAUNCH, THE PLT ADDED HEAT TO TAKEOFF & SIGNALED FOR A RELEASE, BUT THE QUICK RELEASE LINE FAILED TO RELEASE. THE BLN SETTLED TO THE GND & 'BOBBED' UP & DWN 2 TIMES. THE PLT RPRTD THAT AT THE HEIGHT OF A BOUNCE (ABT 6 TO 10 FT), ALL 28 OF THE ADVANCED FIBER TECHNOLOGY (AFT) KEVLAR SUSPENSION CABLES FAILED. THE BASKET FELL TO THE GND & THE ENVELOPE ROSE TO ABT 500 TO 700 FT, THOUGH THE RED LINE STAYED ATTACHED TO THE BASKET & OPENED THE DEFLATION PORT; 2 OF THE 7 OCCUPANTS RCVD SERIOUS INJURIES. AN EXAM REVEALED STRENGTH DEGRADATION OF THE KEVLAR CABLES DUE TO HEAT EXPOSURE. THE BLN HAD 240 HRS OF FLT TIME. STRENGTH LOSS WAS FND IN SOME AFT/KEVLAR CABLES OF OTHER BLNS. ON 11/28/90, AEROSTAR INTL SVC BULLETIN #129 WAS ISSUED TO RETROFIT ALL S-66A & S-77A BNS WITH STEEL CABLES.
Probable cause
STRENGTH DEGRADATION OF THE KEVLAR SUSPENSION CABLES, DUE TO PREVIOUS HEAT DAMAGE. FACTORS RELATED TO THE ACCIDENT WERE: FAILURE OF THE QUICK RELEASE LINE TO RELEASE, AND SUSCEPTIBILITY OF KEVLAR SUSPENSION CABLES TO HEAT.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX91LA038
- Event ID
- 20001212X24641
- Case number
- LAX91LA038
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 35f3dce2b8ca137d1df6dacf4d727b51db38ae13f6f7372acd73a80dbe3e1640; retrieved 2026-09-21T15:33:14.332Z.