# NTSB ATL90LA182: Helio HST-550A, N5779N, Mobile, AL, September 29, 1990

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: September 29, 1990, 10:17 local (15:17 UTC)
- Place: Mobile, AL
- Coordinates: 30.809291, -88.189872 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=30.8093&lon=-88.1899&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious, 9 uninjured
- Status: Completed, report December 30, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 8283
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL90LA182
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8283/pdf
- Page: https://openairdocs.org/ntsb/ATL90LA182

## Probable cause

THE PILOT'S INTENTIONAL ATTEMPTED TAKEOFF WITH A KNOWN TAILWIND COMPONENT. FACTORS RELATING TO THE ACCIDENT WERE THE TAILWIND, TREES AND UTILITY LINES ON THE DEPARTURE END OF THE TAKEOFF AREA.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight encounter with weather, takeoff - initial climb
  - weather condition - tailwind (contributing factor)
  - preflight planning/preparation - inadequate, pilot in command (cause)
- In flight encounter with weather, descent - emergency
  - object - tree(s)
  - object - wire,transmission

## Analysis

THE AIRPLANE COLLIDED WITH TREES AND POWER LINES DURING TAKEOFF FROM A 2000 FOOT LONG OPEN AREA WITH 10 PARACHUTISTS ABOARD. THE PILOT SAID HE EXPERINENCED AN UNSOLICITED ROLLBACK IN ENGINE POWER PRIOR TO THE COLLISION. REPORTEDLY, SOME POWER WAS REGAINED. HOWEVER, NOT IN TIME TO AVOID THE COLLISION. BUT, THE JUMP CLUB CHAIRMAN REPORTED THAT NO CHANGE IN THE ENGINE'S OPERATION WAS OBSERVED THROUGHOUT THE MISHAP. WITNESSES AT THE TAKEOFF AREA REPORTED THAT THE WINDS WERE 12 KNOTS OUT OF THE NORTHEAST, WHICH WOULD HAVE GIVEN THE FLIGHT A QUARTERING TAILWIND COMPONENT FOR THE TAKEOFF. ACCORDING TO THE FLIGHT MANUAL, THE MAXIMUM DEMONSTRATED CROSSWIND IS 12 KNOTS. THE EXAMINATION OF THE AIRPLANE FAILED TO INDICATE ANY SYSTEM MALFUNCTION OR FAILURE.

## Aircraft

- Registration: [N5779N](https://openairdocs.org/deregistered/N5779N-2012-12-10), registration cancelled 2012-12-10, S/N 006, built 1972 (OpenAirDocs)
- Reported make and model: HELIO HST-550A
- Registry model: [Helio HST-550A](https://openairdocs.org/model/helio-hst-550a) (registry code 4301006) (OpenAirDocs)
- Registry engine: [Pratt & Whitney Canada PT6A-60A](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-60a) (registry code 52043, turbo-prop) (OpenAirDocs)
- Category: Airplane
- Serial number: 006
- Engines: P&W PT 6A-34 750 horsepower turbo prop
- Damage: Destroyed
- Flight: Part 91
- Operator: Mullins, Howard M.

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 1, valid medical--no waivers/lim.; flight hours: 12,482 total, 410 in this make and model, 11,722 as pilot in command, 205 in the last 90 days, 63 in the last 30 days, 7 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 40° at 5 knots
- Visibility: 8 statute miles
- Lowest ceiling: 10,000 ft broken
- Temperature: -0 °F, dew point -0 °F
- Observed at: BFM, 2 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19900929043379A](https://openairdocs.org/incident/19900929043379A), Sep 29, 1990: Helio HST550A, Mobile, AL, Destroyed. Struck trees and power line departing parking lot with quartering tailwind. Report partial powerloss not confirmed.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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