WPR11LA306

NTSB accident investigation · Grumman American Avn. AA-5 · Yacoit, WA · July 5, 2011

Accident · Serious injuriesLimited investigationFinal report
Date
July 5, 2011, 10:50 local (17:50 UTC)
Place
Yacoit, WA
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N1334RGrumman American Avn. AA-5
Defining event
Enroute-climb to cruise: Controlled flight into terr/obj (CFIT)
Weather
Visual (VMC) · Day
Status
Completed · report May 21, 2014
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
FAA FSDO
FAA report
20110705025149A
Case key
80989

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The pilot’s failure to maintain clearance from terrain.

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Not attained/maintainedGrumman American Avn. AA-5: 2 casesAll aircraft: 1,310 casesProbable cause
Terrain: mountainous/hilly terrainEnvironmental issues › Physical environment · Awareness of conditionGrumman American Avn. AA-5: 1 caseAll aircraft: 329 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot reported that the airplane was climbing to cruise altitude up a valley in mountainous terrain when he felt a "small bump" and that the airplane subsequently began descending. While maintaining a low altitude to avoid overlying controlled airspace, he initiated a left turn to avoid rising terrain ahead, but a wing collided with a tree. The airplane came to rest in a gravel pit. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.

Factual narrative

On July 5, 2011, about 1050 Pacific daylight time, a Grumman AA-5, N1334R, collided with a tree and then terrain near Yacoit, Washington. The pilot/owner was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The commercial pilot and one passenger sustained serious injuries; the airplane sustained substantial damage from impact forces. The personal cross-country flight departed Grove Field, Camas, Washington, about 1040, with a planned destination of Grant County Regional/Ogilvie Field, John Day, Oregon. Visual meteorological conditions prevailed, and a visual flight rules (VFR) plan had been filed.The pilot reported that he departed straight out from runway 25, and opened his flight plan. He contacted Portland Approach Control for VFR flight following. Approach Control instructed him to remain clear of the class C airspace until they had positive radar identification. The pilot reversed his course, and the airplane was back abeam Grove Field. He remained on an easterly heading, and climbed to 2,400 feet. He observed rising terrain to the east. He decided to head back to the west, and maintained a reduced power setting and 100 miles per hour (mph) airspeed. Portland Approach contacted the pilot and stated that they had radar contact, and queried when he could accept a clearance to continue on course. He replied that he could proceed on course immediately, and indicated that his position was about 4 miles from the Gymme intersection, which was the first waypoint on his planned route of flight. He requested to cruise at 9,500 feet mean sea level (msl). He added full power, and began a climbing left turn to proceed on course. The pilot stated that he did not lose adequate terrain clearance at any time during the course reversal. The airplane was at full power climbing about 400-500 feet per minute. About 3,000 feet msl, he felt a small bump, and noted that the airspeed dropped to 80 mph. He verified that the throttle was in full, and then noticed that the airspeed dropped to 60 mph, which he said was 2 mph above the clean stall speed. While maintaining 60 mph with full power, the airplane began descending. At this point, the pilot noticed that a large fir tree was in the airplane's path; he stated that the airplane had about 1,000 feet of clearance above the tree's elevation prior to the bump. He started a gentle 4-degree bank turn to avoid the tree. The airplane descended until the right wing collided at midspan with a smaller unseen tree. The airplane came to rest in a gravel pit. Both the pilot and passenger sustained broken legs and lacerations; the pilot sustained broken fingers on his right hand as well, which he attributed to his maintaining the full throttle position until touchdown. The pilot stated that his preflight forecast was for calm conditions to 6,000 feet, and he did not encounter any turbulence during the flight. The Federal Aviation Administration (FAA) accident coordinator interviewed abystander who came to the aid of the airplane's occupants. The bystander arrived about 5 minutes after the crash; he observed one person with a shattered ankle standing by the left side of the airplane, and one person still in the right seat. He noted that he saw a small fuel leak from under the left wing, and there was a fuel odor. Two FAA inspectors examined the airplane on scene. They observed a 5-gallon bucket under the left wing with about 1/2 inch of fuel in it. They opened the fuel caps on each wing tank, but could not determine if any or how much fuel was in the tanks. The FAA accident coordinator interviewed the pilot. The pilot indicated that he was maintaining a low altitude to avoid the controlled airspace above him. The pilot initiated a left turn to avoid rising terrain ahead, and could not estimate the altitude above ground level (agl). The pilot did not think that winds were a factor, but that the airplane might have been too low at the intuition of the turn. The FAA accident coordinator interviewed the passenger. The passenger stated that he was looking around enjoying the flight and the scenery as they were heading up a valley. He did recall looking at the engine gauges as this time, and the engine rpm was in the green operating range. The engine sounded good up until the end. As he looked back to the front of the airplane, he and the pilot almost simultaneously stated that they were not going to make it. The pilot indicated that they would be all right if they could get between two trees. The airplane hit one of the trees, and then the ground. The passenger was not sure what direction the airplane was headed or if it was turning. He felt that all changes to the airplane's flight path were controlled at all times, and did not think that there were air pockets, updrafts, or downdrafts that affected the airplane's flight path.

Aircraft

Registration
N1334R
Reported as
Grumman American Avn. AA-5
Category
Airplane
Serial number
AA5-0734
Airframe hours
2,926
Engine
Lycoming O-320-C2G, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Steven L Emerson
Registered owner
Steven L Emerson
Airworthiness certificate
Standard, Aerobatic; Standard, Normal
Last inspection
Annual · June 22, 2011
Departed
Yacoit, WA
Destination
GCD · John Day, OR
Flight plan
VFR

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
54
Injuries
Serious
Certificates
Private, Commercial, Flight engineer
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
November 23, 2010
Seat
Left
Flight hours
494 total · 394 in this make and model · 412 as pilot in command · 21 in the last 90 days · 21 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
70 °F, dew point 54 °F
Altimeter
30.12 inHg
Observed at
KTTD

Docket · 4

The files NTSB released with the investigation on April 7, 2014, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.4 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.

Other investigations on N1334R · 1

Matched to the same aircraft by N-number and date.