Rockwell S2R accident near Harlan, Iowa, July 20, 2020
On July 20, 2020 at about 9:00 pm local time, a 1973 Rockwell S2R, registered N1662S, was substantially damaged in an accident during maneuvering (low-alt flying) near Harlan, Iowa. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The fatigue fracture of the upper rudder hinge that resulted in a partial separation of the rudder from the airplane during a spray pass.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 20, 2020 · about 9:00 pm local time · cases in 2020
- Place
- Harlan, Iowa · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Rockwell S2R No Series, built 1973
- Registration
- N1662S · registry record · serial 1835R
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The pilot of the aerial application flight was spraying a field when the top portion of the rudder partially separated from the airplane. The airplane yawed abruptly left and remained in an uncontrollable left yaw for about 10 to 15 minutes, at times pitching uncontrollably downward until the broken portion of the rudder separated. The airplane landed without further incident. Postaccident metallurgical examination of the upper rudder hinge revealed a fatigue fracture.
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
- Part(s) separation from AC during maneuvering (low-alt flying) defining event
- Aircraft maintenance event during prior to flight
The NTSB's findings
- Aircraft › Aircraft structures › Empennage structure › Rudder › Fatigue/wear/corrosion other cases naming the airframe structure
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 5,533 hours in all; 1,160 in this make and model; 230 in the last 90 days; 226 in the last 30 days; 5,486 as pilot in command; 943 on instruments
- Last flight review: March 25, 2019
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: ctr
- Injury: no injuries
The aircraft
- Airframe total time: 11,955 hours
- Last inspection: 100-hour inspection, July 11, 2020
- Maximum gross weight: 6,900 lb
- Seats: 1
- Landing gear: fixed
- Engine: Honeywell TPE331-10 (turboprop); 500 hours total
The flight
- Departed from: HNR Harland IA at 8:30 pm
- Destination: HNR Harland IA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: at 6 knots
- Sky: broken clouds at 3,900 ft; a few clouds at 3,000 ft
- Temperature: 77°F (25°C), dew point 63°F (17°C)
- Altimeter: 30.01 inHg
- Observation at 3:55 pm from HNR
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Photographs from the investigation 4 pictures from the NTSB's docket, as the NTSB released them
Photo 1: Photo of Empennage
Photo 2: Top Rudder Hinge
Photo 3: Middle Rudder Hinge
Photo 4: Lower Rudder HingeThe NTSB's photographs with the NTSB's captions, at screen size. Open a picture to see it full size or to report one that should not be shown.
Documents from the investigation the NTSB's docket: the evidence folder behind the report
6 documents, released by the NTSB on March 2, 2022. 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 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 7 pages | View Download |
| 2 | Record of Correspondence FAA | PDF, 1 page | View Download |
| 3 | Materials Laboratory Factual Report 20-058 | PDF, 7 pages | View Download |
| 4 | Ad 79-10-10 | PDF, 3 pages | View Download |
| 5 | SB-AG-15 | PDF, 4 pages | View Download |
| 6 | Photo Log | PDF, 4 pages · our copy | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Connections how this case links to the rest of the register
- N1662S on the register today · the tail number may have moved to another aircraft since
- Rockwell 14 aircraft on the register
- Engine: Honeywell TPE331-10 13 aircraft carry this series today · as the NTSB recorded it
- Harlan Municipal · departed from
- Accidents and incidents in Iowa 871 since 1982 · 131 in the last ten years
- Iowa 4,513 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/CEN20LA294.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.