# NTSB MKC72FCD05: Brantly B2B, N2161U, Spencer, IA, July 9, 1971

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: July 9, 1971
- Place: Spencer, IA · SPENCER, IA
- Location: 43.1470° N, 95.1527° W: Placed by OpenAirDocs: center of Spencer, IA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=43.1470&lon=-95.1527&mi=10
- Phase of flight: [Uncontrolled descent](https://openairdocs.org/ntsb-phases/650) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 2, 1972
- Report: Brief approved by the director
- NTSB case key (mKey): 162598
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC72FCD05
- Page: https://openairdocs.org/ntsb/MKC72FCD05

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-2459   71/7/9    SPENCER,IOWA        BRANTLY B2B         CR-  0  0  1  MISCELLANEOUS             COMMERCIAL, AGE 33, 551
        TIME - 2130                    N2161U              PX-  0  0  0  TEST                      TOTAL HOURS, 478 IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        NAME OF AIRPORT - SPENCER
        DEPARTURE POINT             INTENDED DESTINATION
          SPENCER,IOWA                LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           COLLISION WITH GROUND/WATER: CONTROLLED                  IN FLIGHT: UNCONTROLLED DESCENT
        PROBABLE CAUSE(S)
           ROTORCRAFT - FLIGHT CONTROL SYSTEMS: STABILIZING SURFACES-DAMPERS
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
        REMARKS- LEAD-LAG DAMPER FAILED CAUSING R/B HOP.DESCENT UNCONTROLLABLE.
```

## Aircraft

- Registration: [N2161U](https://openairdocs.org/deregistered/N2161U-2014-09-16), registration cancelled 2014-09-16, S/N 322, built 1963 (OpenAirDocs)
- Reported make and model: BRANTLY B2B
- Registry model: [Brantly B-2B](https://openairdocs.org/model/brantly-b-2b) (registry code 1440506) (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
- Airport: Spencer

## Other investigations on N2161U (3)

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 FTW84LA381](https://openairdocs.org/ntsb/FTW84LA381), Sep 8, 1984: Brantly Helicopter B-2B (N2161U), Alvin, TX, destroyed
- [NTSB MKC73DCD12](https://openairdocs.org/ntsb/MKC73DCD12), Aug 6, 1972: Brantly B-2B (N2161U), Marshalltown, IA, destroyed
- [NTSB UNK64X1811](https://openairdocs.org/ntsb/UNK64X1811), May 17, 1964: Brantly B2B (N2161U), Port Jefferson, NY, substantial 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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