# NTSB IAD97LA121: Pohlman/Pohlman Rotorway Exec 90, N94CJ, Westminster, MD, September 21, 1997 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: September 21, 1997, 14:45 local (18:45 UTC) - Place: Westminster, MD - Coordinates: 39.649612, -77.0401 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.6496&lon=-77.0401&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report February 28, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 28234 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=IAD97LA121 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/28234/pdf - Page: https://openairdocs.org/ntsb/IAD97LA121 ## Probable cause The loss of power due to carburetor icing. A factor to this accident was the carburetor heat was not accessible from within the cockpit. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, approach - vfr pattern - final approach - weather condition - carburetor icing conditions (cause) - carburetor heat - unavailable, pilot in command (contributing factor) - Forced landing, descent - emergency ## Analysis The pilot remained in the traffic pattern for 40 minutes in his homebuilt helicopter, performing takeoffs and landings. At 200 feet on final approach with 19 inches of manifold pressure set, the engine stopped running. During the forced landing, the pilot maneuvered to avoid an embankment and impacted the ground damaging the tail boom and rotor blades. Examination of the engine revealed no mechanical malfunctions. The temperature/dew point was: 57 degrees Fahrenheit and 38 degrees Fahrenheit, respectively. Utilizing the 'Icing Probability Curves' charts, these temperatures combined with a glide power setting, placed the carburetor within the serious icing range. Examination of the helicopter revealed that the carburetor heat was preset prior to the flight and not accessible from inside the cockpit. After the accident, the FAA recommended to the manufacturer that a switch be placed in the cockpit. The manufacturer completed a modification allowing control of the carburetor heat from inside the cabin. ## Factual narrative On September 21, 1997, about 1445 eastern daylight time, a homebuilt Rotorway Exec 90, N94CJ, was substantially damaged as it impacted the ground during a forced landing at Carroll County Regional/Jack B. Poage Field (W54), Westminster, Maryland. The certificated private pilot/co-owner received minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the personal local flight conducted under 14 CFR Part 91. The pilot flew the helicopter in the traffic pattern for 40 minutes, performing takeoffs and landings. He reported that "at 200 feet on final approach with 19 inches of manifold pressure set, the engine stopped running." The pilot recalled glancing at the carburetor air temperature gauge and it was not in the yellow caution range. During the descent, the pilot maneuvered to avoid an embankment and impacted the ground damaging the tail boom and rotor blades. A Federal Aviation Administration (FAA) Inspector examined the helicopter. His examination revealed no mechanical malfunctions with the engine. The Inspector reported that the engine started and ran without any difficulty. A pilot, who had flown a another helicopter, told the Inspector that he was required to use carburetor heat that morning. The temperature/dew point recorded by the Automated Weather Observing System (AWOS) at W54 was: 57 degrees Fahrenheit and 38 degrees Fahrenheit, respectively. Utilizing the "Icing Probability Curves" charts, these temperatures combined with a glide power setting, placed the carburetor within the serious icing range. Examination of the helicopter revealed that the carburetor heat was preset prior to flight, and not accessible from inside the cockpit. After the accident, the FAA recommended to the manufacturer that a switch be placed in the cockpit. The manufacturer completed a modification allowing control of the carburetor heat from inside the cabin. ## Aircraft - Registration: [N94CJ](https://openairdocs.org/deregistered/N94CJ-2018-01-29), registration cancelled 2018-01-29, S/N 5043, built 1991 (OpenAirDocs) - Reported make and model: Pohlman/Pohlman ROTORWAY EXEC 90 (ROTORWAY E) - Registry model: [Pohlman J W/Pohlman C ROTORWAY EX 90](https://openairdocs.org/model/pohlman-j-w-pohlman-c-rotorway-ex-90) (registry code 05604FD) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Helicopter, amateur-built - Serial number: 5043 - Airframe hours: 26 - Engines: Rotorway RI-162 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: John W. Pohlman - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, June 28, 1997, 26 hours before - Departed: W54 - Airport: W54, Carroll County Regional, runway 34, 5,100 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 762 total, 201 in this make and model, 710 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 30° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: 4,100 ft overcast - Temperature: 57 °F, dew point 37 °F - Altimeter: 30.00 inHg - Observed at: W54 ## 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 19970921027769A](https://openairdocs.org/incident/19970921027769A), Sep 21, 1997: Amtr ROTORWAYEXEC, Westminister, MD, Substantial damage. Experimental rotorway lost engine power and crashed. Other circumstances are unknown. (.4) on September 21, 1997, about 1445 eastern daylight time, a homebuilt… 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.