Cessna 172S N1835U

Summary

On 16 April 2011 at about 16:00 local time, a Cessna 172S registered N1835U, operated by Westwind School of Aeronautics, was involved in an accident near Payson, Arizona, United States. 2 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

16 April 2011 at 16:00

Classification

Accident

Location

Payson, Arizona, United States

Nearest airport

Payson (PAN)

Coordinates

34.2597, -111.3578

Aircraft

Cessna 172S

Registration

N1835U

Category

Airplane

Engines

1

Operator

Westwind School of Aeronautics

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Deer Valley → Payson

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR11LA201

Nobody was injured.

The pilot's decision to conduct a touch-and-go arrival during his first flight to a high elevation airport, which resulted in an improper mixture adjustment and a partial loss of engine power for the takeoff and attempted climbout.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The private pilot and his passenger departed on a flight to an airport with an elevation of 5,157 feet mean sea level (msl), and a density altitude of about 6,200 feet. Although the pilot had received classroom instruction on high elevation airport, high density altitude operations, the flight was his first to a high elevation airport, and he planned to conduct his first landing there as a touch-and-go. After touchdown, the pilot retracted the flaps, applied full throttle, and lifted off. The pilot perceived that the airplane was underperforming on the climbout, and he enriched the fuel-air mixture, which did not rectify the problem. The engine was making "popping" sounds, the airspeed was lower than normal, and the tachometer indicated about 500 rpm less than the target value. The pilot began a right turn back toward the airport, and lowered the airplane’s nose to increase airspeed, but the airplane entered a spin and impacted terrain. Postaccident examination of the airframe and engine did not reveal any preimpact mechanical failures or malfunctions that would have precluded normal operation. Review of the pilot's history revealed that he received all his training and flight experience through a flight school that was based at an airport with an elevation of about 1,500 feet msl. The pilot's full enrichment of the mixture for the takeoff and climbout at the destination airport was contrary to the procedure published in the airplane manufacturer's Pilot's Operating Handbook, which stated that the mixture was to be leaned for maximum rpm. Considering the dynamic conditions and limited time available to ensure proper mixture adjustment during a touch-and-go landing at a high-elevation airport, and the effect of an improper mixture on airplane climb capability at such an airport, the pilot deprived himself of potential safety margins by deciding to conduct his arrival as a touch and go. His lack of any prior operations at high elevation airports further reduced his safety margin by depriving him of applicable experience. Subsequent to the accident, the pilot’s flight school implemented several new policies regarding operations at high elevation airports, including a prohibition against pilots operating solo at such airports until they have done so with a flight instructor.

Quoted verbatim from the NTSB record.