# NTSB UNK64X1476: Brantly B2, N4997C, Thetford, VT, April 26, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: April 26, 1964
- Place: Thetford, VT · THETFORD, VT
- Location: 43.8356° N, 72.2485° W: Placed by OpenAirDocs: center of Town of Thetford, VT, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=43.8356&lon=-72.2485&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report January 11, 1965
- Report: Brief approved by the director
- NTSB case key (mKey): 184873
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK64X1476
- Page: https://openairdocs.org/ntsb/UNK64X1476

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
2-0130  64/4/26    THETFORD VT         BRANTLY B2          CR-  0  0  1  MISCELLANEOUS             COMMERCIAL, FL.INSTR.,
        TIME - 1800                    N4997C              PX-  0  0  1  DEMONSTRATION             AGE 25, 1453 TOTAL HOURS,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            46 IN TYPE, NOT
                                                                                                   INSTRUMENT RATED.
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           STALL                                                    TAKEOFF: INITIAL CLIMB
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - FAILED TO MAINTAIN ADEQUATE ROTOR R.P.M.
```

## Aircraft

- Registration: [N4997C](https://openairdocs.org/deregistered/N4997C-2012-08-09), registration cancelled 2012-08-09, S/N 32, built 1960 (OpenAirDocs)
- Reported make and model: BRANTLY B2
- Registry model: [Brantly B-2](https://openairdocs.org/model/brantly-b-2) (registry code 1440502) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Substantial damage

## Other investigations on N4997C (2)

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 NYC73DHD73](https://openairdocs.org/ntsb/NYC73DHD73-169032), Dec 19, 1972: Brantly B-2 (N4997C), Downingtown, PA, substantial damage
- [NTSB NYC70D0002](https://openairdocs.org/ntsb/NYC70D0002-107185), Nov 23, 1969: Brantly B-2 (N4997C), Millville, NJ, 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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