CHI96IA200 · Boeing 727-30C
Boeing 727-30C · Incident: loss of engine power en route
From Louisville Muhammad Ali International Airport (SDF) to Chicago Rockford International Airport (RFD)
Event
- NTSB case
- CHI96IA200
- 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
- Incident
- 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
Boeing 727-30C
- Aircraft type
- Boeing 727
- Category
- Airplane
- 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
- N906UP
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Louisville Muhammad Ali International Airport (SDF), Louisville, KYTo Chicago Rockford International Airport (RFD), Rockford, IL
- 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
- En route · descent
- 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
- Loss of engine power
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Fuel starvation
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- None
Cause areas
- Fluid, fuel › Starvation
- Fuel system, line › Low pressure
- Fuel system, pump › Surge
- Production/design personnel › Acft/equip, inadequate design
Approximate · Estimated position: the centre of Chicago, IL, the place the record names. Not the accident site.
NTSB narrative
The airplane experienced a total loss of power on all three engines, and a subsequent loss of electrical generating power, during an en route descent in preparation for landing at Greater Rockford Airport, Rockford, Illinois. The crew declared an emergency and diverted to Chicago, Illinois. A landing was made at Chicago O'Hare International Airport with all engines operating and electrical generating power restored. The investigation revealed that the airplane was modified by Supplemental Type Certificate (STC) to replace the original Pratt and Whitney engines with Rolls Royce Model TAY engines, but using the original fuel system. The original system was subject to fuel surges which were acceptable to the original installation. With the TAY engine configuration, when the airplane's fuel system is configured with one engine operating in suction feed, air and vapor evolve from the fuel in the engine and airplane fuel systems, and accumulates at the fuel system high points. When boosted fuel is restored to the system, the boosted fuel flow rate moves toward the high end of the boost pump output capacity, causing a rapid filling and recompression of the air and vapor areas with a resulting high flow velocity. The fuel is then decelerated to 'engine demand flow rate' as it reaches the engine high-pressure fuel pump. This change in the velocity of the fuel flow causes a 'pressure spike' which is first observed at the inlet to the engine high-pressure fuel pump. The formation of the pressure spike is accompanied by a rapid drop in engine high-pressure fuel pump output and fuel burner line pressures leading to a collapse in engine combustor discharge pressure and engine flameout. The formed pressure spike travels from the first engine back through the airplane's fuel system into the other exposed engines causing these engines to flameout in a similar manner. The elapsed time at which the pressure spike travels back through the fuel system to the other engines is just under one second.
Probable cause
low pressure in the fuel lines caused when the crossfeed valve was closed and the boost pumps to the effected fuel tank were turned off, a fuel pressure surge (spike) accompanied by a rapid drop in high pressure pump output and burner line pressures, when boosted fuel was reintroduced to the system, which resulted in temporary fuel starvation to the three engines, and the inadequate aircraft/equipment design by production personnel (STC holder). A factor which contributed to this incident was the flight engineer's management of the fuel system.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI96IA200
- Event ID
- 20001208X05915
- Case number
- CHI96IA200
- 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, damage. 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: c923ec6d79cea4da38942b78289ec140ec96ee0bbb2e081970c90174a93a0229; retrieved 2026-09-22T22:16:07.442Z.