NTSB Factual Report

HISTORY OF FLIGHT

On September 15, 2002, at 1312 mountain daylight time, a Piper PA-24-260, N8822P, and a Beech 1900D, N240GL, operating as Great Lakes Airlines Flight 5111 from Denver, Colorado (DEN), to Rock Springs, Wyoming, nearly collided at the intersection of runway 21 and runway 27 at Rock Springs-Sweetwater County Airport (RKS), Rock Springs, Wyoming. Both airplanes were landing on different intersecting runways. The PA-24-260 was landing on runway 21 (5,223 feet by 75 feet, dry asphalt). The Beech 1900D was landing on runway 27 (10,000 feet by 150 feet, dry asphalt). In an effort to avoid a collision, the private pilot of the PA-24-260 initiated a go-around, pitched the airplane nose up, experienced a loss of control, and impacted the terrain. The PA-24-260 was substantially damaged. The Beech 1900D, piloted by an airline transport pilot, continued the landing roll and taxied to parking. The Beech 1900D sustained no damage. Visual meteorological conditions prevailed at the time of the accident. The PA-24-260 was on a personal, cross-country flight from Reno, Nevada, to Rock Springs, Wyoming, and was operating under the provisions of Title 14 CFR Part 91 without a flight plan. The Beech 1900D was operating on an instrument flight rules flight plan as scheduled, domestic passenger service under the provisions of Title 14 CFR Part 121. The pilot and passenger on board the PA-24-260 reported no injuries. The captain, first officer, two flight crew members riding in the cabin, and 10 passengers on board the Beech 1900D sustained no injuries.

In his written statement, the pilot of N8822P said that he began monitoring the "Unicom/CTAF (Common Traffic Advisory Frequency)" for RKS 122.8 Megahertz (MHz) at approximately 75-80 miles from the airport. When they were 20 miles west of the airport, the pilot said he began radioing on Unicom. The pilot said his first transmission was "Rock Springs traffic Comanche 8822 Papa 20 miles west, planning runway 21. Any traffic in the area, please report." The pilot said they heard no response. The pilot said he made similar traffic pattern position calls when entering the pattern on left crosswind, and on downwind, base leg, initial final, and 1 mile final. The pilot said that over the approach end of runway 21 with the wheels just about to touchdown, his wife shouted on the intercom "look at that plane" and threw her arm across the pilot to point at what was at their 8 o'clock position. The pilot said he saw an airplane on runway 27 at a fast roll approaching the runway 21/27 intersection. The pilot said he judged that the two airplanes would meet at the intersection. The pilot said his immediate thought was that he had to take immediate action. He said he applied full power to the engine pulled the nose up into a landing attitude, and veered left so as to pass behind the airplane. "Seconds later we struck the ground in a tail low attitude just past RW27 and to the left of RW21. We bounced tail low, I pulled the power off and we struck the sagebrush and ground in a horizontal attitude. On evacuating the airplane, the pilot said he saw the other airplane arriving at the passenger terminal."

In an interview statement, the captain of N240GL said the first officer was flying the airplane on the leg from DEN to RKS. He said that they were cleared for a visual approach by the Air Route Traffic Control Center (ARTCC). They briefed the visual approach for runway 27 with an instrument landing system approach back up. The captain said they monitored the Airport Weather Observing System (AWOS) frequency, 118.37 MHz, and then made an "in range" call to the Great Lakes Station at RKS on frequency 131.32 MHz, where he provided his estimated time of arrival and put in a request for fuel. The captain said at 20 to 25 miles out, he made his first radio call on the CTAF, 122.8 MHz, and requested any aircraft at Rock Springs please advise. He said he continued to make advisory calls at 15, 10, and 5 miles from the airport and on short final for runway 27. On short final and approximately 200 feet above ground level, the captain said they received a TCAS (Terrain Clearance Avoidance System) traffic advisory showing "+300 feet," but then it disappeared. The captain said he made the advisory call on short final because of the TCAS warning. The captain said they touched down, rolled out and taxied to the gate. The captain said he learned of the accident involving N8822P when they were deplaning. When asked if he requested an airport advisory on the CTAF, the captain said he did not. When asked if he heard any other traffic on the RKS CTAF, the captain said no.

A pilot, deadheading to RKS and sitting in seat 6C on N240GL, said that during rollout she noticed an airplane that appeared to be landing on runway 21 coming directly at the airplane. She said the airplane climbed and flew over the top of N240GL. She said she looked left and saw the airplane impact the ground in a cloud of dust.

A station agent for Great Lakes Airlines said he saw N240GL coming in and a smaller airplane coming in on the left hand side. The agent said they seemed very close. He said as N240GL touched down, the smaller airplane kept "swerving and stalling (until) it hit the ground."

FLIGHT RECORDERS

The cockpit voice recorder (CVR) from N240GL was removed from the airplane and sent to the NTSB CVR Laboratory. On October 9, 2002, the recorder tape was examined. The voice tape indicated that the captain of Flight 5111 made a company in-range radio call to the station at RKS. The voice tape indicates that the crew monitored AWOS for weather information. The voice tape indicates that the crew made five traffic advisory calls to Rock Springs traffic.

WRECKAGE AND IMPACT INFORMATION

A Federal Aviation Administration inspector examined N8822P at RKS. The airplane rested upright in a field approximately 1,100 feet southwest of the runways intersection. One propeller blade was bent aft. The airplane's right wing was bent upward approximately 10 degrees at mid-span. The upper and lower wing skins were bent and buckled. The fuselage and empennage were bent upward aft of the baggage compartment. Flight control continuity was confirmed. An examination of the cockpit configuration showed the airplane's number 1 communications radio set to a frequency of 122.8 MHz. An examination of the engine, engine controls, and other airplane systems revealed no anomalies.

TESTS AND RESEARCH

Air Route Traffic Control Center radar showed N8822P approach RKS from the west-southwest. At 1309:39, N8822P entered a left downwind leg that positioned the airplane east of and parallel to runway 21. At the same time, ARTCC radar showed N240GL on a descending straight in approach to runway 27 approaching from the east. At 1310:08, ARTCC radar showed N240GL approximately 3.5 nautical miles from the approach end of runway 27 at 7,800 feet msl. At the same time, N8822P was over the approach end of runway 27, midway on his downwind leg for runway 21, at 7,600 feet msl, and 2.33 nautical miles west of N240GL at the Beech 1900D's 12 o'clock position. ARTCC radar showed N8822P continue a left-hand traffic pattern that positioned the airplane on a 1 mile final for runway 21. Radar showed both airplanes continued inbound for landings on their respective chosen runways. The data shows both airplane tracks came together at the intersection of both runways at 1311:34.

The three Great Lakes Airlines station agents on duty at RKS recalled that Flight 5111 (N240GL) called "in range" and made a fuel order on the Base Operations Company Frequency, 131.32 MHz, approximately 15 minutes prior to landing. The station agents then went outside to meet the airplane.

Two fire fighters at the RKS fire station, monitoring the CTAF, said they heard N8822P call in bound for landing on runway 21. One of the fire fighters said he heard N8822P call in three or four times. He said he never heard the Great Lakes flight crew make any radio calls over CTAF. The other fire fighter said they received a telephone call from one of the Great Lakes station agents informing them that Flight 5111 was inbound. He said they opened the door to the fire station. He said that they heard N8822P a couple of times, but didn't hear from Great Lakes. He said he wondered where they were. The fire fighter said, "Then, as I was looking for the plane, I saw this other plane over the top of Great Lakes' tail. The airplane hit the dirt."

The radios on N240GL were examined and determined to be fully functional.

The airport manager at RKS stated the Unicom/CTAF is not manned continuously. Persons, when on duty at the airport, respond to airport advisory requests on a time permitting basis. He said that to his knowledge, no advisories were requested by Flight 5111 (N240GL), nor were any advisories given to Flight 5111.

ADDITIONAL INFORMATION

Parties to the investigation were the FAA Flight Standards District Office, Denver, Colorado, the FAA Flight Standards Field Office, Casper, Wyoming, and Great Lakes Airlines, Incorporated.

The cockpit voice recorder was returned to Great Lakes Airlines, Incorporated.

NTSB Probable Cause

the pilot of the Piper and the flight crew of the Beech's failure to attain proper clearance from each other during their respective landings and the intentional evasive maneuver by the pilot to avoid the other airplane. Factors contributing to the accident were inadequate visual lookout by the pilot and the crew of the other airplane and the inadvertent stall.