WPR13FA335 · Mooney M20C
Mooney M20C · Accident: loss of control in flight during initial climb
From Lake Tahoe Airport (KTVL) to Palo Alto Airport (KPAO)
Event
- NTSB case
- WPR13FA335
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 1 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Mooney M20C
- Aircraft type
- Mooney M20
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N6709U
- Operator
- Lefton Steven A
- Onboard fatalities
- Unknown
- Route
- From Lake Tahoe Airport (KTVL), South Lake Tahoe, CATo Palo Alto Airport (KPAO), Palo Alto, CA
- Aircraft age
- About 50 years (built 1963)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Initial climb
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of control in flight
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Personnel issues › Action/decision
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The airplane was departing from a high-altitude airport. After liftoff, about midfield on runway 36, the pilot elected to turn right for a downwind departure. After the right turn, the pilot expressed concern to the passenger that the airplane could not outclimb the rapidly rising terrain. The pilot banked left to avoid a tree near the top of a ridge. The right front seat passenger heard the stall warning horn come on, and the airplane descended into the trees, coming to rest inverted on the forest floor.
Based on atmospheric conditions and an airport elevation of 6,269 feet, the calculated density altitude was 9,044 feet. According to the airplane's pilot operating handbook, for those conditions, the pilot could expect about a 330- to 490-feet-per-minute (fpm) rate of climb. The best angle-of-climb airspeed was about 82 mph. To clear the ridge ahead (180 feet above the airport elevation, not including trees), which was within 1/4 mile, the airplane would have to maintain a 981-fpm rate of climb, which was not possible given the density altitude at the time of departure.
The Federal Aviation Administration's Airport Facility Directory for the departure airport noted that the airport was surrounded on the east, south, and west by rapidly rising terrain. It further noted that for noise abatement the preferred departure runway was 36 and advised pilots to continue straight out for 1 mile before making turns.
A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.
Probable cause
The pilot’s decision to turn into rising terrain that would have required performance in excess of the airplane’s maximum climb rate to clear after taking off at a high density altitude.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR13FA335
- Event ID
- 20130722X51944
- Case number
- WPR13FA335
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: a009b4229307e3c6e0635a35cadbdd4b5784910e2c0ff580e282eec97dd9a74a; retrieved 2026-09-14T16:00:55.950Z.