# NTSB DEN99FA157: Piper PA-28-181, N4366D, Villa Grove, CO, September 1, 1999 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: September 1, 1999, 08:25 local (14:25 UTC) - Place: Villa Grove, CO - Coordinates: 38.250934, -105.949661 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=38.2509&lon=-105.9497&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Fatal - Injuries: 2 fatal - Status: Completed, report November 2, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 47258 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN99FA157 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47258/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=47258 - Page: https://openairdocs.org/ntsb/DEN99FA157 ## Probable cause The flight instructor's improper inflight decision to enter a narrow blind/box canyon, and his misjudgment of the vertical and lateral clearances. A factor was the downdrafts. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - In flight collision with terrain/water, maneuvering - turn to reverse direction - terrain condition - blind/box canyon (contributing factor) - in-flight planning/decision - improper, pilot in command(cfi) (cause) - altitude/clearance - misjudged, pilot in command(cfi) (cause) - weather condition - downdraft (contributing factor) ## Analysis An FBI pilot, along with two other special agents in separate airplanes, was receiving agency-sponsored mountain flying instruction. His instructor announced that they were going to practice box canyon turnarounds. Shortly thereafter, white smoke was seen coming from the side of the mountain. Evidence indicates the airplane struck tree tops while in a steep left descending turn in what was described as an extremely tight box canyon. ## Factual narrative HISTORY OF FLIGHT On September 1, 1999, approximately 0825 mountain daylight time, a Piper PA-28-181, N4366D, operated by Colorado Skyways, Inc., of Colorado Springs, Colorado, was destroyed when it collided with mountainous terrain and burned 10 miles northwest of Villa Grove, Colorado. The commercial rated flight instructor and the commercial rated pilot receiving instruction were fatally injured. Visual meteorological conditions prevailed for the instructional flight being conducted under Title 14 CFR Part 91, and a company VFR flight plan had been filed. The flight originated at Colorado Springs approximately 0730. The investigation revealed that the Federal Bureau of Investigation had contracted with Colorado Skyways to train those special agents who were also pilots in mountain flying techniques. Each week during the months of August and September, training classes of three agents each were conducted (8 weeks, 24 agents). This was the third year Colorado Skyways had provided this training. The company has 10 airplanes in its fleet, including 6 Cessna 172s and a Piper PA-28-181, and employs 5 full time and 6 part time flight instructors. Since it also has a contract with the U.S. Air Force Academy to provide introductory flight training for cadets, only two Cessna 172s were available for FBI use. It was decided that the tallest agent would fly the Piper PA-28-181. Three special agents arrived in Colorado Springs on Monday, August 30 to begin the fifth mountain flying class of 1999. The next day, they attended 4 hours of ground school that included a briefing for the next day's flight. FBI officials could find no evidence that the special agent had ever flown in a low wing airplane. The following is based on interviews with the two surviving special agents and their flight instructors. The special agents arrived at the airport approximately 0700 on September 1, and, along with their flight instructors, preflighted and loaded their respective airplanes. One of the instructors obtained a computer printout of the forecast weather. Visual meteorological conditions were expected to prevail, with relatively light surface and winds aloft (7 knots at 9,000 feet, 14 knots at 12,000 feet). A company VFR flight plan was left at the front desk prior to departure. The three airplanes took off from Colorado Springs Municipal Airport in loose formation approximately 0730, and flew southwestward at 7,500 feet msl (mean sea level), skirting Cheyenne Mountain and the Fort Carson restricted area (R-2601 A&B). The formation then turned and followed the Arkansas River and U.S. Highway 50 to Coaldale (see attached Denver Sectional Chart for the approximate route). The pilots stayed in contact with each other by communicating on CTAF (common traffic advisory frequency) 122.75 mHz. At Coaldale, the airplanes turned west and entered Hayden Pass (summit 10,709 feet msl). As they approached the pass, standing lenticular clouds were noted to the northwest. It was decided that they would climb to a higher altitude, utilizing thermals for additional lift. N4366D, the Piper PA-28-181, crossed the pass first at an altitude of 11,800 feet msl, followed by N96319 and N97890 at 11,300 feet msl. The wind was said to be light and the air smooth. There were high scattered clouds. The time was between 0815 and 0820. The formation turned north towards Salida, Colorado. The instructor aboard the lead airplane, the PA-28-181 (N4366D), announced that he and his student were going to practice box canyon turnarounds. The other instructors followed suit and demonstrated to their students the emergency procedure for egress from a box canyon. As the maneuvers were being performed, white smoke was seen coming from the side of a mountain about 700 or 800 feet below its summit. Repeated radio calls to N4366D went unanswered. While one airplane circled the area, the other airplane flew to Salida to see if N4366D had landed there. It was determined it had not. The pilot of a U.S. West helicopter overheard the radio conversation and offered his assistance. The helicopter was led to the site and made a low pass over the fire. The pilot reported seeing aircraft parts. He later described the canyon as being "tight." Shortly after 0900, a "Mayday" message was broadcast of frequency 121.5 mHz. An airliner heard the call, and passed the information to FAA's (Denver) air route traffic control center (ARTCC), who in turn notified search and rescue authorities. According to the Saguache County Sheriff's Office, a report of a forest fire on Hunters Peak, south of Dorsey Creek, was logged at 0827. The first report of a possible aircraft accident was received at 0907. Sheriff's deputies also took two statements (attached as EXHIBITS to this report) from hunters in the area who purportedly saw an airplane and heard a crash. The times given did not coincide with the time of the accident. The accident occurred during the hours of daylight at a location of 38 degrees, 23.551 minutes north latitude, and 105 degrees, 57.853 minutes west longitude, or 9.6 miles on a 145 degree bearing from the Salida airport. PERSONNEL INFORMATION The flight instructor and pilot-in-command was seated in the right front seat of the airplane. Born on July 12, 1942, he was 57 years old. He held a commercial pilot certificate with airplane single, multiengine, and instrument ratings. He also held a flight instructor certificate with airplane single engine and instrument ratings. His second class airman medical certificate, dated February 22, 1999, contained the limitation, "Holder shall wear corrective lenses." He also possessed documentation indicating he had received physiological (altitude chamber) training at Edwards Air Force Base, California, on August 13, 1996. According to Colorado Skyways, the pilot relocated to Colorado Springs, from Riverside, California. He was interviewed in February and hired in April 1999. He received a Part 141 standardization check in a Cessna 172 on April 23, 1999. He received airplane checkouts in the Piper PA-28-181 on May 12, 1999, and the Cessna TR182 on June 3, 1999. His last biennial flight review was accomplished in May 1998, and his most recent instrument competency check was done in March 1999. Although his logbook was never located, company records indicate he had logged 2,858 total flight hours, of which 1,835 were as a flight instructor. The pilot receiving instruction was seated in the left front seat of the airplane. Born on October 14, 1959, he was 39 years old. He held a commercial pilot certificate with airplane single engine land, rotorcraft-helicopter, and instrument ratings in both airplanes and helicopters. His second class airman medical certificate, dated March 23, 1999, contained no limitations or restrictions. Although his logbook was never located, FBI records indicate he had logged approximately 2,500 total flight hours, of which 1,883 hours were accrued in U.S. Army helicopters, and 617 hours were accrued in single engine civilian airplanes. AIRCRAFT INFORMATION N4366D, a model PA-28-181 (s/n 28-8490088), was manufactured by the Piper Aircraft Corporation in December 1984. It was equipped with a Textron Lycoming O-360-A4M engine (s/n L-27490-36A), rated at 180 horsepower, and a Sensenich 2-blade, all metal, fixed pitch propeller (m/n 76ERM8S5-0-60). According to the airplane maintenance records, the last 100-hour, annual, and 50-hour inspections were accomplished on February 11, July 9, and August 20, 1999, respectively. At the time of the latter inspection, the airframe and engine had accrued a total time in service of 8,325.3 hours, and 7,751.2 hours (524.8 hours since major overhaul), respectively. The engine had been overhauled on November 21, 1997. METEOROLOGICAL INFORMATION Harriet Alexander Field, located 2 miles west of Salida, is about 10 miles northwest o ## Aircraft - Registration: [N4366D](https://openairdocs.org/deregistered/N4366D-2012-12-07), registration cancelled 2012-12-07, S/N 28-8490088, built 1984 (OpenAirDocs) - Reported make and model: Piper PA-28-181 - Registry model: [Piper PA-28-181](https://openairdocs.org/model/piper-pa-28-181) (registry code 7102807) (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: 28-8490088 - Airframe hours: 8271 - Engines: Lycoming O-360-A4M 180 horsepower reciprocating - Damage: Destroyed - Fire: On-Ground - Flight: Instructional, Part 91 - Operator: Colorado Skyways, doing business as Aerolease Company - Registered owner: Debalco Enterprises, Inc - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 9, 1999 - Departed: COS, COLO. SPRINGS, CO - Destination: 0V2, SALIDA, CO - Flight plan: Company VFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 57; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: right; toxicology performed; flight hours: 2,858 total, 2,581 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 350° at 2 knots - Temperature: 55 °F, dew point 25 °F - Altimeter: 29.00 inHg - Observed at: OV2 ## 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 19990901044919A](https://openairdocs.org/incident/19990901044919A), Sep 1, 1999: Piper PA28181, Villa Grove, CO, No damage, 2 fatal. (-23) The accident airplane was one in a flight of three airplanes being used to train fbi pilots in mountain flying techniques. According to the other two fbi… ## Docket (19 files) The files NTSB released with the investigation on August 2, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=47258. 2.1 MB in all. - Supplement a (item 1, PDF, 2 pages, 266 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517902&FileExtension=pdf&FileName=Supplement%20A-Master.pdf - Supplement b (item 2, PDF, 4 pages, 359 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517904&FileExtension=pdf&FileName=Supplement%20B-Master.pdf - Supplement e (item 3, PDF, 2 pages, 322 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17461031&FileExtension=pdf&FileName=Supplement%20E_Redacted-Rel.pdf - Witnesses statements (item 4, PDF, 2 pages, 345 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17461764&FileExtension=pdf&FileName=Witnesses%20Statements_Redacted-Rel.pdf - Weather reports and records (item 5, PDF, 1 page, 83 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517910&FileExtension=pdf&FileName=Weather%20Reports%20and%20Records-Master.pdf - Map of accident area (item 6, PDF, 1 page, 29 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517914&FileExtension=pdf&FileName=Map%20of%20Accident%20Area-Master.pdf - Saguache county sheriff's dispatch log (item 7, PDF, 1 page, 153 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17461687&FileExtension=pdf&FileName=Saguache%20County%20Sheriff%27s%20Dispatch%20Log_Redacted-Rel.pdf - Statement of party representatives to NTSB investigation (item 8, PDF, 1 page, 129 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17461806&FileExtension=pdf&FileName=Statement%20of%20party%20Representatives%20to%20NTSB%20Investigation_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 9, PDF, 1 page, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17461110&FileExtension=pdf&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15_Redacted-Rel.pdf - Toxicological reports (item 10, PDF, 2 pages, 244 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17461597&FileExtension=pdf&FileName=Toxicology%20Reports_Redacted-Rel.pdf - Photo-1_ view to the east at hunters peak arrow depicts approximate accident site (item 11, PDF, 1 page, 12 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517932&FileExtension=pdf&FileName=Photo-1_View%20to%20the%20east%20at%20Hunters%20Peak%20%20Arrow%20depicts%20approximate%20accident%20site-Master.pdf - Photo-2_ closer view of south face of hunters peak arrow depicts apprximate accident site (item 12, PDF, 1 page, 13 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517936&FileExtension=pdf&FileName=Photo-2_Closer%20view%20of%20%20south%20face%20of%20Hunters%20Peak%20%20Arrow%20depicts%20apprximate%20accident%20site-Master.pdf - Photo-3_ center section of aircraft fuselage and main spar assembly (item 13, PDF, 1 page, 15 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517940&FileExtension=pdf&FileName=Photo-3_Center%20section%20of%20aircraft%20fuselage%20and%20main%20spar%20assembly-Master.pdf - Photo-4_ right outboard wing section depicting wing impact damage (item 14, PDF, 1 page, 14 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517944&FileExtension=pdf&FileName=Photo-4_Right%20outboard%20wing%20section%20depicting%20wing%20impact%20damage-Master.pdf - Photo-5_ left outboard wing section (item 15, PDF, 1 page, 11 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517948&FileExtension=pdf&FileName=Photo-5_Left%20outboard%20wing%20section-Master.pdf - Photo-6_ forward cockpit and instrument panel (item 16, PDF, 1 page, 15 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517952&FileExtension=pdf&FileName=Photo-6_Forward%20cockpit%20and%20instrument%20panel-Master.pdf - Photo-7_ the engine and propeller (item 17, PDF, 1 page, 15 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517956&FileExtension=pdf&FileName=Photo-7_The%20engine%20and%20propeller-Master.pdf - Photo-8_ rear view of tail section (item 18, PDF, 1 page, 14 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517960&FileExtension=pdf&FileName=Photo-8_Rear%20view%20of%20tail%20section-Master.pdf - Photo-9_ stabilator trim drum assembly (item 19, PDF, 1 page, 14 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7517964&FileExtension=pdf&FileName=Photo-9_Stabilator%20trim%20drum%20assembly-Master.pdf From the NTSB's public API. 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