Saturday, July 8, 2017

Piper PA-28R-180 Cherokee Arrow, N7444J: Accident occurred June 18, 2013 at Durango–La Plata County Airport (KDRO), Colorado

Additional Participating Entity:
 Federal Aviation Administration / Flight Standards District Office; Salt Lake City, Utah

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms  

Aviation Accident Data Summary - National Transportation Safety Board: https://app.ntsb.gov/pdf

http://registry.faa.gov/N7444J

NTSB Identification: CEN13LA358
14 CFR Part 91: General Aviation
 in Durango, CO
Probable Cause Approval Date: 03/24/2014
Aircraft: PIPER PA-28R-180, registration: N7444J
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

The pilot reported that, in accordance with operating procedures, he leaned the engine’s fuel-air mixture before takeoff to compensate for the high-density altitude (the departure airport had a density altitude of 9,355 feet). During takeoff, the airplane accelerated to 80 mph, lifted off the runway, and climbed to about 100 feet above ground level. The pilot stated that the airplane seemed “sluggish” and that it stopped climbing. The airplane rapidly descended, the pilot made a controlled landing off the departure end of the runway, and the airplane’s wings were substantially damaged when they struck several approach lights. Fuel was found on board, and it was not contaminated. The examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. An engine ground run was conducted, and the engine developed full power. The runway length was sufficient for a safe take off. The high-density altitude and the tailwind likely contributed to airplane’s reduced performance. 

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's improper decision to take off with a tailwind at a high-density altitude, which resulted in the airplane’s failure to maintain the initial climb rate.

On June 18, 2013, about 1130 mountain daylight time, a Piper PA-28R-180, N7444J, sustained substantial damage when it impacted runway lights during a forced landing after takeoff from runway 21 (9,201 feet by 150 feet, asphalt) at the Durango – La Plata County Airport (DRO), Durango, Colorado. The private pilot and passenger were not injured. The airplane was registered to and operated by the pilot under the provisions of the 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. The flight was departing DRO and the destination was Tyler, Texas.

The pilot reported that he obtained a weather brief and conducted a walk-around inspection of the airplane before engine start. After engine start, the pilot leaned the air-fuel mixture to compensate for the high density altitude and to get the engine running smoothly. He taxied to the run-up area and he completed the preflight checklist. The magnetos checks were normal. He briefly put in full power and adjusted the mixture to obtain the best rpm setting, and then brought the throttle back to idle. 

The pilot advanced the throttle to full power during the takeoff from runway 21. The airplane accelerated to 80 mph, lifted off the runway, and climbed to about 100 feet above ground level. The pilot reported that the airplane seemed "sluggish," which he attributed to the high density altitude. The airplane approached the end of the runway and it stopped climbing despite having the power at full throttle and no change to the air-fuel mixture or the propeller pitch. He reported that the oil pressure and fuel pressure were both in the green, but the airspeed and altitude were inadequate to attempt a return to a paved runway. Although there was no evidence that the engine was "missing," the airplane rapidly descended, and the pilot made a controlled landing about 400 yards off the departure end of the runway. Upon touchdown, the pilot pulled the throttle fully aft and applied the brakes. The airplane's wings struck several approach lights which resulted in substantial damage to the wings. 

The 74-year-old pilot, who was a co-owner of the airplane, held a private pilot certificate with a single-engine land rating. He had 617 total flight hours with 325 hours in make and model. He held a third class medical certificate. 

The airplane was a single-engine Piper PA-28R-180 equipped with a 180 horsepower Lycoming IO-360-B1E engine. The maximum gross weight of the airplane was 2,500 pounds, which at the time of the accident weighed 2,269 pounds. The last annual maintenance inspection of the airplane was conducted on June 1, 2013, with an airframe time of 3,497 hours. The engine had 151 hours since the last overhaul. 

The 1100 surface weather observation at DRO was: wind 090 degrees at 12 knots; sky clear; visibility 10 miles; temperature 24 degrees Celsius (C); dew point 13 degrees C, altimeter 30.18 inches of mercury. 

An examination of the airplane and an engine ground run were conducted at DRO. The examination revealed that the left fuel tank was ruptured during the accident and no fuel remained in the tank. The right main tank was about 3/4 full. Fuel samples from the right main tank and the fuel strainer had no contaminants or water present. The engine control continuity and full travel of all the engine controls were confirmed. The propeller was pulled through by hand and all cylinders exhibited about the same amount of compression. The inside of the mufflers were inspected and no blockage was found. The engine was started, warmed up, and the magneto checks were completed. The idle and idle mixture checks were completed. The engine was run at full power with the boost pump on and off. The full engine power run was completed with the mixture leaned out and also with the mixture at full rich. The propeller was set at take-off (low pitch, high rpm) as well as pulled back to a cruise rpm setting. No discrepancies were found during the engine ground run. 

The elevation at DRO is 6,685 feet. The calculated density altitude was 9,355 feet. The calculated crosswind component was about 10.4 knots from the left with about a 6.1 knot tailwind component. The performance charts in the Piper Cherokee 'Arrow' Owner's Handbook indicate that the calculated take-off distance at maximum gross weight with a no-wind condition would be about 3,800 feet. The performance charts did not provide the take-off distance for a tailwind condition. The calculated climb performance was about 380 feet per minute.

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