# NTSB OAK73IP031: Sikorski S-61N, N307Y, S.Francisco, CA, March 29, 1973

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Closed
- Date: March 29, 1973
- Place: S.Francisco, CA · S.FRANCISCO, CA
- Location: 37.7750° N, 122.4194° W: Placed by OpenAirDocs: center of San Francisco, CA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=37.7750&lon=-122.4194&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 10 uninjured
- Status: Completed, report April 19, 1973
- Report: Brief approved by the director
- NTSB case key (mKey): 173582
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=OAK73IP031
- Page: https://openairdocs.org/ntsb/OAK73IP031

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
4-0004  73/3/29    S.FRANCISCO,CALIF   SIKORSKI S-61N      CR-  0  0  3  SCHED DOM PASSG SRV       AIRLINE TRANSPORT, AGE
        TIME - 1554                    N307Y               PX-  0  0  7                            UNK/NR, UNK/NR TOTAL
                                       DAMAGE-MINOR        OT-  0  0  0                            HOURS, UNK/NR IN TYPE,
                                                                                                   NOT INSTRUMENT RATED.
        CLASSIFIED AS INCIDENT
        OPERATOR - SAN FRANCISCO AND OAKLAND HELICOPTER AIRLINES
        DEPARTURE POINT             INTENDED DESTINATION
          BERKELEY,CALIF              S.FRANCISCO,CALIF
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           AIRFRAME FAILURE: IN FLIGHT                              IN FLIGHT: NORMAL CRUISE
        PROBABLE CAUSE(S)
           AIRFRAME - FUSELAGE: DOORS,DOOR FRAMES
           MISCELLANEOUS ACTS,CONDITIONS - IMPROPERLY SECURED
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - SEPARATION IN FLIGHT
        EMERGENCY CIRCUMSTANCES - PRECAUTIONARY LANDING ON AIRPORT
                                  SUSPECTED OR KNOWN AIRCRAFT DAMAGE
        REMARKS- CARGO DOOR CAME OPEN,FLT ATTENDANT UN TO SECURE. DOOR SEPARATED,HIT M/R BLADE.CONT FLT & LND OK.
```

## Aircraft

- Registration: N307Y (not matched to a registry record)
- Reported make and model: SIKORSKI S-61N
- Category: Helicopter
- Engines: turbo shaft
- Damage: Minor damage

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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