# NTSB MIA75FKA09: Hiller Acft UH-12E, N9781C, San Juan, PR, April 28, 1975

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: April 28, 1975
- Place: San Juan, PR · SAN JUAN, PR
- Location: 18.4663° N, 66.1057° W: Placed by OpenAirDocs: center of San Juan, PR, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=18.4663&lon=-66.1057&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report August 4, 1975
- Report: Brief approved by the director
- NTSB case key (mKey): 148740
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA75FKA09
- Page: https://openairdocs.org/ntsb/MIA75FKA09

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-1590  75/4/28    SAN JUAN,PR         HILLER ACFT UH-12E  CR-  0  0  1  MISCELLANEOUS             COMMERCIAL, AGE 42, 6381
        TIME -                         N9781C              PX-  0  0  1  TEST                      TOTAL HOURS, 1644 IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        NAME OF AIRPORT - PUERTO RICO INTL
        DEPARTURE POINT             INTENDED DESTINATION
          SAN JUAN,PR                 LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           COLLISION WITH GROUND/WATER: UNCONTROLLED                IN FLIGHT: HOVERING
        PROBABLE CAUSE(S)
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: IMPROPER MAINTENANCE (MAINTENANCE PERSONNEL)
           ROTORCRAFT - FLIGHT CONTROL SYSTEMS: CYCLIC PITCH CONTROL SYSTEM
           MISCELLANEOUS ACTS,CONDITIONS - IMPROPERLY INSTALLED
        REMARKS- CYCLIC RODS IMPROPERLY CONNECTED TO BELLCRANKS.MOVEMENT IN FORE AFT DIR RESULTED LATERAL CTL INPUT
```

## Aircraft

- Registration: [N9781C](https://openairdocs.org/deregistered/N9781C-1991-05-03), registration cancelled 1991-05-03, S/N 2257 (OpenAirDocs)
- Reported make and model: HILLER ACFT UH-12E
- Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Substantial damage
- Airport: Puerto Rico Intl

## 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 19750428009459A](https://openairdocs.org/incident/19750428009459A), Apr 28, 1975: Hiller UH12E, San Juan, Puerto Rico, Substantial damage. Cyclic rods improperly connected to bellcranks. Movement in fore aft dir resulted lateral ctl input

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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