# NTSB FTW70FRG10: Bell 47D1, N4229A, Randolph Afb, TX, February 14, 1970

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: February 14, 1970
- Place: Randolph Afb, TX · RANDOLPH AFB, TX
- Location: 29.5303° N, 98.2789° W: Placed by OpenAirDocs: center of Randolph AFB, TX, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=29.5303&lon=-98.2789&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report June 22, 1970
- Report: Brief approved by the director
- NTSB case key (mKey): 139528
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW70FRG10
- Page: https://openairdocs.org/ntsb/FTW70FRG10

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-0197  70/2/14    RANDOLPH AFB,TEX    BELL 47D1           CR-  0  0  1  INSTRUCTIONAL             COMMERCIAL, AGE 38, 1727
        TIME - 1720                    N4229A              PX-  0  0  0  TRAINING                  TOTAL HOURS, 27 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          SAN ANTONIO,TEX             SAN ANTONIO,TEX
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           HARD LANDING                                             LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - IMPROPER OPERATION OF FLIGHT CONTROLS
        EMERGENCY CIRCUMSTANCES - PRECAUTIONARY LANDING OFF AIRPORT
        REMARKS- PLT STATED ACFT YAWED TO R AT FULL PWR STRAIGHTENED OUT WITH REDUCED PWR.NO REASON FOR YAW FOUND.
```

## Aircraft

- Registration: [N4229A](https://openairdocs.org/deregistered/N4229A-2026-02-02), registration cancelled 2026-02-02, S/N 001, built 1961 (OpenAirDocs)
- Reported make and model: BELL 47D1
- Registry model: [Bell 47D1](https://openairdocs.org/model/bell-47d1) (registry code 1180802) (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

## Other investigations on N4229A (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 BFO90LA042](https://openairdocs.org/ntsb/BFO90LA042), May 13, 1990: Bell 47D (N4229A), Baltimore, MD, substantial damage. Probable cause: THE PILOT APPLIED EXCESSIVE CYCLIC CONTROL, CAUSING THE MAIN ROTOR TO FLEX AND SEVERE THE TAIL CONE.

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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