Amateur-built Vans RV-4 accident near Cortland, Nebraska, October 17, 2015
On October 17, 2015 at about 1:41 pm local time, a 1996 amateur-built Vans RV-4, registered N999ZF, was destroyed in an accident during maneuvering (low-alt flying) near Cortland, Nebraska. It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's decision to intentionally maneuver at a low altitude and his failure to maintain adequate airspeed during the climbing right turn, which resulted in the airplane exceeding its critical angle of attack and experiencing an aerodynamic stall.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 17, 2015 · about 1:41 pm local time
- Place
- Cortland, Nebraska · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built Vans RV-4, built 1996
- Registration
- N999ZF · no longer on the register · serial 2407
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The private pilot and passenger were conducting a personal flight in the single-engine airplane. According to available radar data and an interview with the pilot's brother, the pilot completed several intentional low-altitude passes (at or below 100 ft above the ground) over his brother's property/residence. The pilot's brother, who witnessed the accident, stated that following the final low pass, the airplane pitched up into a climbing right turn. He stated that, during the climbing turn, the airplane suddenly pitched nose-down and descended rapidly. The airplane recovered briefly to a wings-level attitude before the wings rocked left and right and the airplane entered a descending right turn into terrain. A postaccident examination established that the airplane had crashed in a nose-low attitude and was destroyed by impact and postimpact fire damage. The examination did not reveal any anomalies that would have precluded normal operation of the airplane during the flight. Based on the witness description and the impact geometry, it is likely that the pilot did not maintain adequate airspeed during the climbing right turn, which resulted in the airplane exceeding its critical angle of attack and experiencing an aerodynamic stall at a low altitude. Due to the pilot's decision to intentionally maneuver at a low altitude, there was insufficient altitude to fully recover from the aerodynamic stall before impact.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Loss of control in flight during maneuvering (low-alt flying) defining event
- Aerodynamic stall/spin during maneuvering (low-alt flying)
- Fire/smoke (post-impact) during post (impact)
The NTSB's findings
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Airspeed › Not attained/maintained
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Not attained/maintained
- cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 512.5 hours in all; 148.3 in this make and model; 15.8 in the last 90 days; 5.9 in the last 30 days; 501.8 as pilot in command
- Last flight review: July 16, 2014
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: frt
- Injury: fatal
Pilot-Rated Passenger
- Certificate: private
- Ratings: single-engine land
- Flight time: 245.8 hours in all
- Last flight review: July 18, 2014
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: rear
- Injury: fatal
The aircraft
- Airframe total time: 590.5 hours
- Last inspection: condition inspection, November 15, 2014
- Maximum gross weight: 1,600 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming IO-320-D1C (piston); 674 hours total
- Fire on the ground
The flight
- Departed from: CEK Crete NE at 1:33 pm
- Destination: LNK Lincoln NE
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 120° at 9 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 46°F (8°C), dew point 30°F (-1°C)
- Altimeter: 30.48 inHg
- Observation at 1:54 pm from LNK, 25 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
14 documents, released by the NTSB on October 31, 2017. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Witness Statements | PDF, 4 pages | View Download |
| 2 | radar Data Plots | PDF, 6 pages | View Download |
| 3 | radar Data (Source Data) | data file | Download |
| 4 | FAA Airman Registry (Pilot) | PDF, 1 page | View Download |
| 5 | Pilot Logbook (Excerpts) | PDF, 28 pages | View Download |
| 6 | FAA Airman Registry (Passenger) | PDF, 1 page | View Download |
| 7 | Passenger Flight Time Summary (Provided by FAA) | PDF, 1 page | View Download |
| 8 | Airframe Logbook (Excerpts) | PDF, 4 pages | View Download |
| 9 | Engine Logbook (Excerpts) | PDF, 7 pages | View Download |
| 10 | Weather Reports | PDF, 1 page | View Download |
| 11 | Toxicological Report (Pilot) | PDF, 1 page | View Download |
| 12 | Toxicological Report (Passenger) | PDF, 1 page | View Download |
| 13 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 14 | Photos | PDF, 7 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.