# NTSB FTW73DRG66: Bell 47G, N2772, San Antonio, TX, April 4, 1973

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: April 4, 1973
- Place: San Antonio, TX · SAN ANTONIO, TX
- Location: 29.4241° N, 98.4936° W: Placed by OpenAirDocs: center of San Antonio, TX, within about 13 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=29.4241&lon=-98.4936&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 8, 1973
- Report: Brief approved by the director
- NTSB case key (mKey): 170363
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW73DRG66
- Page: https://openairdocs.org/ntsb/FTW73DRG66

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-0651   73/4/4    SAN ANTONIO,TEX     BELL 47G            CR-  0  0  1  INSTRUCTIONAL             COMMERCIAL, AGE 29, 202
        TIME - 1000                    N2772               PX-  0  0  0  TRAINING                  TOTAL HOURS, 21 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        NAME OF AIRPORT - STINSON
        DEPARTURE POINT             INTENDED DESTINATION
          SAN ANTONIO,TEX             LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE: MAIN ROTOR                      IN FLIGHT: HOVERING
           HARD LANDING                                             LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: IMPROPER MAINTENANCE (MAINTENANCE PERSONNEL)
           ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: MAIN ROTOR GEAR BOX
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING ON AIRPORT/SEAPLANE BASE/HELIPT.
        REMARKS- TRANSMISSION SEIZED DUE PINION GR FAILURE IN UPPER PLANETARY SYS.TAIL ROTOR DRIVE SHEARED.
```

## Aircraft

- Registration: [N2772](https://openairdocs.org/deregistered/N2772-2014-09-25), registration cancelled 2014-09-25, S/N 27, built 1947 (OpenAirDocs)
- Reported make and model: BELL 47G
- Registry model: [Bell 47G](https://openairdocs.org/model/bell-47g) (registry code 1181002) (OpenAirDocs)
- Registry engine: [Franklin 6V4 series](https://openairdocs.org/engine/franklin-6v4-series) (registry code 27033, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Substantial damage
- Airport: Stinson

## 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 19730404007579A](https://openairdocs.org/incident/19730404007579A), Apr 4, 1973: Bell 47G, San Antonio, TX, Substantial damage. Transmission seized due pinion gr failure in upper planetary sys. Tail rotor drive sheared.

## Other investigations on N2772 (1)

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.

- [NTSB FTW77FRG02](https://openairdocs.org/ntsb/FTW77FRG02), Oct 12, 1976: Bell 47G (N2772), Kerrville, TX, destroyed

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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