# NTSB DEN92LA041: Enstrom F28, N95NR, Lakewood, CO, March 7, 1992

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: March 6, 1992, 17:45 local (Mar 7, 1992, 00:45 UTC)
- Place: Lakewood, CO
- Coordinates: 39.669509, -105.089248 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.6695&lon=-105.0892&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor, 1 uninjured
- Status: Completed, report June 11, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 18202
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN92LA041
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18202/pdf
- Page: https://openairdocs.org/ntsb/DEN92LA041

## Probable cause

THE PREMATURE USE OF COLLECTIVE BY THE PILOT DURING AN AUTOROTATION. FACTORS WERE:  THE DISCONNECTION AND SUBSEQUENT COLLAPSE OF THE INDUCTION AIR LINE.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of engine power(partial) - nonmechanical, cruise - normal
  - induction air ducting - disconnected (contributing factor)
  - induction air ducting - collapsed (contributing factor)
- Forced landing, descent - emergency
  - autorotation - performed, pilot in command
- In flight collision with terrain/water, descent - uncontrolled
  - collective - premature, pilot in command (cause)
  - terrain condition - roadway/highway

## Analysis

ENGINE POWER WAS LOST AND THE PILOT INITIATED AN AUTOROTATION.  THE PILOT SAID HE HAD 'INDICATIONS POWER WAS NORMAL' SO HE PULLED COLLECTIVE.  THE HELICOPTER IMPACTED A ROADWAY. POST ACCIDENT EXAMINATION DISCLOSED THE FLEXIBLE AIR DUCT, BETWEEN THE AIR FILTER BOX AND THE TURBOCHARGER INLET, HAD BECOME DISCONNECTED AND HAD COLLAPSED.  THE CLAMP SECURING THE AIR DUCT TO THE AIR FILTER BOX WAS LOOSE AND HAD SLIPPED OFF.

## Aircraft

- Registration: N95NR (not matched to a registry record)
- Reported make and model: ENSTROM F28
- Category: Helicopter
- Serial number: 1503
- Airframe hours: 1842
- Engines: LYCOMING HIO-360-F1AD 225 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Gavit, Steven E.
- Registered owner: Gavit, Steven E.
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, November 22, 1991, 44 hours before

## Weather

- Conditions: Visual (VMC), Day
- Wind: 50° at 5 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 52 °F, dew point 27 °F
- Altimeter: 29.00 inHg

## 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 19920306005259A](https://openairdocs.org/incident/19920306005259A), Mar 6, 1992: Enstrm 280F, Lakewood, CO, Substantial damage. Reported power loss. Rotor RPM decay caused hard landing. Found engine air intake duct disconnected and flattened.

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.