Cessna 170B accident near Palmer, Alaska, July 23, 2010
On July 23, 2010 at about 4:00 am local time, a Cessna 170B, registered N4590C, was substantially damaged in an accident during maneuvering (low-alt flying) near Palmer, Alaska. It was a personal flight under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's decision to make a low-altitude pass over a remote airstrip toward rising terrain in weather conducive to downdrafts.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 23, 2010 · about 4:00 am local time
- Place
- Palmer, Alaska · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 170B · all 170Bs on the register
- Registration
- N4590C · no longer on the register · serial 25534
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot stated that he was maneuvering the airplane following a creek and observed an airstrip below. He decided he would make a practice approach to the airstrip, with no intention of landing. On the second approach, upon reaching the threshold of the landing area, he initiated a climb. After flying the length of the airstrip, the airplane started to descend. The pilot opined that the airplane had entered a downdraft and in response applied full engine power. The airplane continued to descend and collided with rising terrain near the end of the airstrip. The airplane sustained structural damage to its wings and fuselage. The airplane was equipped with a required emergency locator transmitter (ELT), however, it was an older generation ELT that transmitted only on 121.5 megahertz, not the newer, digital version that transmits on 406 megahertz. As of February 2009, the search and rescue satellites that receive ELT signals no longer had the capability to receive the older analog 121.5 megahertz ELTs. The 406 megahertz ELTs are received within seconds of activation, and rescuers are notified within minutes of the accident location. In this accident, the pilot and passenger were missing for 2 days and a search was initiated. They were able to walk to a trail, despite serious injuries, where a group of all terrain vehicle riders assisted them.
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
- Low altitude operation/event during maneuvering (low-alt flying) defining event
The NTSB's findings
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Climb rate › Not attained/maintained
- cause Personnel issues › Experience/knowledge › Knowledge › Knowledge of meteorologic cond › Pilot
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- Environmental issues › Conditions/weather/phenomena › Wind › Downdraft › Contributed to outcome
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 537 hours in all; 179 in this make and model; 78 in the last 90 days; 24 in the last 30 days; 485 as pilot in command
- Last flight review: September 21, 2009
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: minor injuries
The aircraft
- Airframe total time: 6,322 hours
- Last inspection: annual inspection, April 23, 2010
- Maximum gross weight: 2,200 lb
- Seats: 4
- Landing gear: fixed
- Engine: Teledyn Continental C-145 (piston); 0 hours total
The flight
- Departed from: PAAQ Palmer AK at 10:00 pm
- Destination: PAAQ Palmer AK
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 15 statute miles
- Sky: broken clouds; scat
- Temperature: 45°F (7°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N4590C the same tail number, which may have belonged to a different aircraft at the time
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.