# NTSB CHI07TA241: Christen Industries A-1, N661FB, Elm Springs, SD, July 30, 2007 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Final report - Date: July 30, 2007, 07:00 local (13:00 UTC) - Place: Elm Springs, SD - Coordinates: 44.2625, -102.526947 - Nearby events: https://openairdocs.org/map.md?lat=44.2625&lon=-102.5269&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report April 30, 2008 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 66350 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI07TA241 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66350/pdf - Page: https://openairdocs.org/ntsb/CHI07TA241 ## Probable cause The pilot not maintaining clearance from the rising terrain. A factor contributing to the accident was the rising terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, maneuvering - terrain condition - rising (contributing factor) - altitude/clearance - not maintained, pilot in command (cause) - terrain condition - ground ## Analysis The airplane impacted rising terrain while maneuvering on a public use animal control flight. The pilot said that he had turned and was heading south and had begun a shallow descent to maintain a constant altitude above down-sloping terrain. The pilot said, "As we continued to descend I noticed a slight rise in the terrain and determined that we had plenty of altitude to clear that rise and continued on with my southerly flight path and shallow descent. As we approached the slight rise in the terrain the pressure in the stick changed very quickly with a movement in the pitch axis only. The pressure came back immediately and then there was another pressure change in the stick that was a little more pronounced. This movement was identical to the other in that it was a pitch change only; there was no movement in the roll direction. After the second time the pitch change changed I made a remark to the gunner and the crash took place." Flight control continuity was confirmed. An examination of the airplane's systems revealed no anomalies. ## Factual narrative On July 30, 2007, about 0700 mountain daylight time, N661FB, registered as a Christen Industries Inc. A-1 airplane, operated by the State of South Dakota, sustained substantial damage when it impacted rising terrain while maneuvering near Elm Springs, South Dakota. Visual meteorological conditions prevailed at the time of the accident. The public use animal control flight was being conducted under 14 Code of Federal Regulations Part 91. No flight plan was on file. The pilot and passenger sustained minor injuries and went to a hospital. The local flight originated from the Wall Municipal Airport, near Wall, South Dakota, at 0615. The pilot stated in his accident report that he had turned and was heading south. He said that he had begun a shallow descent to maintain a constant altitude above the terrain, which was lowering toward a river bottom. The pilot's accident report, in part, further stated: As we continued to descend I noticed a slight rise in the terrain and determined that we had plenty of altitude to clear that rise and continued on with my southerly flight path and shallow descent. As we approached the slight rise in the terrain the pressure in the stick changed very quickly with a movement in the pitch axis only. The pressure came back immediately and then there was another pressure change in the stick that was a little more pronounced. This movement was identical to the other in that it was a pitch change only; there was no movement in the roll direction. After the second time the pitch change changed I made a remark to the gunner and the crash took place. At 0652, the recorded weather at the Rapid City Regional Airport, near Rapid City, South Dakota, was: Wind 150 degrees at 7 knots; visibility 10 statute miles; sky condition clear; temperature 21 degrees C; dew point 17 degrees C; altimeter 29.97 inches of mercury. ## Aircraft - Registration: [N661FB](https://openairdocs.org/deregistered/N661FB-2008-05-20), registration cancelled 2008-05-20, S/N 1175, built 1991 (OpenAirDocs) - Reported make and model: Christen Industries Inc. A-1 - Registry model: [Christen Industries A-1](https://openairdocs.org/model/christen-industries-a-1) (registry code 221020X) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1175 - Airframe hours: 4189 - Engines: Lycoming O-360-C1G 180 horsepower reciprocating - Damage: Substantial damage - Flight: Public aircraft - state, Part 91 - Registered owner: State of South Dakota - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 1, 2006 - Departed: 6V4, Wall, SD - Destination: 6V4, WALL, SD ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: minor; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review August 1, 2006; seat: front; flight hours: 5,944 total, 222 in this make and model, 5,875 as pilot in command, 157 in the last 90 days, 42 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 150° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 70 °F, dew point 63 °F - Altimeter: 29.96 inHg - Observed at: RAP, 26 nm away ## 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 20070730022589A](https://openairdocs.org/incident/20070730022589A), Jul 30, 2007: Chris A1, Elm Springs, SD, Destroyed. (-23) The accident occurred on 7-30-07 about 0700 MDT near Elm Springs, SD. The pilot and passenger (gunner) who work for the state of south dakota were… 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.