NTSB Factual Report

HISTORY OF FLIGHT

On November 21, 1998, at 1253 hours mountain standard time, a Cessna 172P, N99064, collided with a Cessna TR182, N6342T, while entering the traffic pattern at Scottsdale airport, Scottsdale, Arizona. Both aircraft were destroyed. The solo student pilot in N99064 and a private pilot receiving dual instruction in N6342T sustained fatal injuries. The flight instructor in N6342T received serious injuries. N99064 was operated by Scottsdale Flyers, LLC, as an instructional flight and was returning to the airport for landing when the accident occurred. N6342T was operated by the private pilot/owner on an instructional flight and was departing the airport traffic pattern at the time of the accident. Both aircraft were operated under 14 CFR Part 91. N6342T was originating from the Scottsdale airport and N99064 had originated earlier from the same airport about 1150. Visual meteorological conditions prevailed at the time and no flight plans were filed for either flight.

During the investigation, the air-ground communications tapes at the Scottsdale Air Traffic Control Tower were reviewed. A full transcript of the communications is appended to this report. In addition, interviews were conducted with the local and ground controllers on duty in the tower cab. A summary of communications and events derived from these sources and leading to the collision is presented below, beginning with the local time.

--1248:47: N99064 reported his position to the Scottsdale ATCT local controller as 3 miles west of the Paradise Valley Mall, inbound for a full-stop landing, with information Whiskey. The controller cleared him into the Class D airspace (Paradise Valley Mall is about 4.5 miles from the center of the airport) and told him to enter a right downwind for runway 21. He was also told to "report the mall inbound for downwind."

--1249:21: N99064 reported his position as 2 miles west of the mall. The controller repeated his request for him to report over the mall. N99064 acknowledged the request.

--1249:35: N7140B (a Cessna A152) reported that he was holding short of runway 21. He requested a right crosswind departure to the north. The controller cleared him "into position and hold." The pilot repeated the clearance.

--1250:04: N6342T reported that he was holding short of runway 21, and that he was also requesting a right crosswind departure to the north. The controller instructed him to hold short. N6342T acknowledged his instructions.

--1250:16: N7140B was cleared for takeoff and at 1250:21, N6342T was instructed to taxi into position and hold.

--1250:29: The controller asked N7140B if he could "move up past the 45" and the pilot replied in the affirmative.

--1250:43: The controller informed N99064 that there would be two aircraft making right downwind departures momentarily. N99064 asked the controller if he would like him to make 360-degree turns. The controller replied in the negative and instructed the pilot to enter the downwind and to "maintain visual from the traffic." N99064 acknowledged his instructions.

--1250:00: The controller cleared N6342T to takeoff and told him that a Cessna was over the mall, inbound to downwind. N6342T acknowledged the transmission but stated that he had "negative contact."

--1250:13: N6342T reported that he was rolling on takeoff.

--1251:49: The controller informed N99064 that the first of the previously advised departures was now in a right crosswind turn. N99064 replied that "I'm looking."

--1251:54: The controller informed N7140B that his traffic was off his left wing, north of the mall and inbound for a right downwind. N7140B replied that he still had negative contact.

--1252:06: The controller told N6342T that as he made his right turn, his traffic would be at his 11 o'clock position, about 2 miles, northeast bound and in the pattern. N6342T replied that he was still looking for the traffic.

--1252:20: N99064 reported to the controller that he had a Cessna in front of him. The controller acknowledged and told him that he had additional traffic off his right wing that was currently in a right crosswind turn. There was no discernable reply from N99064.

--1252:32: N6342T reported that he had "traffic in sight." The controller replied by advising him to "maintain visual from the traffic." N6342T acknowledged his instructions.

--1252:40: The controller advised N99064 that "traffic has you in sight." N99064 acknowledged the call.

--1252:55: The controller asked N99064 if he was "sure you got that traffic in sight off your right wing now?" N99064 replied that he did not have the traffic in sight. The controller responded by saying that the traffic was now off his right wing.

--1253:19: The controller cleared N99064 to land, telling him to "fly it right to the numbers" if he could and asking him if he was "alright."

There were no further communications from either N99064 or N6342T. The on-duty controller was relieved about 1255:03 and left the tower cab.

During his interview, the local controller said he thought that N6342T would pass behind N99064.

Witnesses on the ground reported hearing a "pop" and seeing a puff of smoke followed by the "tail" separating from one aircraft. The aircraft without the "tail" then spiraled downward until striking the ground accompanied by another loud sound. At the point that the collision occurred, small debris was seen fluttering to earth. The other aircraft continued northbound, descending until colliding with terrain. Several witnesses estimated the altitude of both aircraft about 500 feet agl at the time the collision occurred.

PERSONNEL INFORMATION

The pilot of N99064 was a student pilot whose training had commenced on July 18, 1998. All of his training had been conducted at or around the Scottsdale airport. He had first soloed on October 11, 1998, with 22.3 hours of instruction. He was returning from a local area flight. His student pilot certificate had an endorsement for a Cessna 172. His pilot logbook contained a solo endorsement authorizing flight in the northeast practice area, as well as to and from Phoenix-Deer Valley Municipal and Glendale Municipal airports. His third-class medical certificate required that he have glasses available for near vision.

The flight instructor in N6342T had received his commercial certificate on June 7, 1998. His flight instructor certificate was issued on October 22, 1998. He had given a total of 13.8 hours of dual instruction at the time of the accident. He had a total of 2.9 hours in the same make and model as the accident aircraft. There were no restrictions or limitations on his first-class medical certificate.

The dual student received his private pilot, single engine land, certificate on November 10, 1993. His flight training commenced on September 3, 1992, and he had accumulated 90.1 flight hours by the time of his flight check. He obtained a complex aircraft endorsement on October 20, 1995. He failed in his first flight test for an instrument rating on October 27, 1995. The flight check was not reflected in his pilot logbook. There was no record of a retest for the rating. Following the unsuccessful flight check, there was a period of inactivity from October 26, 1995, until he resumed receiving dual instruction on October 9, 1998. He had accumulated 204.9 hours of flight time, with 27.8 hours in the same make and model as the accident aircraft. According to his flight instructor, he was attempting to attain recurrency for a biennial flight review (BFR). His third-class medical certificate required that he have glasses available for near vision.

The Air Traffic Control Specialist who was working the local control position at the time of the accident entered on duty with the Federal Aviation Administration (FAA) on September 2, 1997, in the Scottsdale ATCT. He possessed an FAA Control Tower Operator certificate, which was issued on April 29, 1988. He completed local control position certification on October 13, 1997, and received a facility rating for Scottsdale on November 29, 1997. The specialist's DBRITE certification was dated November 3, 1998. The last tape talk session was conducted on June 5, 1998, and the most recent technical training discussion occurred on September 30, 1998, with no issues identified.

AIRCRAFT INFORMATION

The maintenance records of N99064 and N6342T were examined by FAA airworthiness inspectors and Safety Board investigators with no deficiencies noted. Both aircraft were equipped for VFR flight in controlled airspace.

COMMUNICATIONS

Review of the communications tapes disclosed that the ATCT local controller communicated with 28 aircraft between 1230 and 1310. There were four instances of unintelligible or partially unintelligible transmissions during that time.

AIRPORT INFORMATION

Scottsdale airport is a VFR ATCT that is equipped with digital-bright radar indicating terminal equipment (D-BRITE), which obtains data from the Phoenix airport surveillance radar (ASR)-9. According to quality assurance personnel in the Western Pacific Region (AWP), due to terrain restrictions, radar target returns in the Scottsdale area cannot be seen below 3,000 feet msl, and are intermittently seen between 3,000 and 4,500 feet msl. The traffic pattern altitude at Scottsdale is 2,500 feet msl. The D-BRITE has an automated conflict alert that advises controllers when two aircraft begin to lose separation. The altitude limitations of the radar system have existed for several years.

Continuous data recording (CDR) data from the Phoenix terminal radar approach control (PHX/P50) was not being recorded at the time of the accident. According to Phoenix terminal radar approach control (TRACON) personnel, both disks that record the data were full. The appropriate keyboard command to cause the CDR to overwrite the older of the two disks had not been entered. The optical drive system (ODS) had stopped and did not record any data for a period of 4 hours.

The noise abatement procedures at the Scottsdale airport funnel traffic to the northwest side of the airport.

WRECKAGE AND IMPACT INFORMATION

Safety Board investigators arrived at the accident site about 1600 on the day of the accident. N99064 was located in an undeveloped desert area adjacent and west of a fairway near the northeast corner of the Kierland golf course. The aircraft was found oriented on a magnetic heading of 352 degrees. The geographic coordinates were 33 degrees 37.487 minutes north latitude and 111 degrees 56.052 minutes west longitude.

There was a circular impact scar about 1 foot in depth and 5 feet in diameter. The propeller was separated from the crankshaft flange and was found midway along the 36-foot distance between the impact scar and the main wreckage. The magnetic bearing from the impact scar to the main wreckage was 352 degrees. There was extensive leading edge crushing visible on both main wings. The forward fuselage was crushed aft to the leading edge of the main wings.

The empennage of N99064 was located on the south side of the 6600 block of Greenway Parkway, adjacent to a public sidewalk. In addition to the separation from the fuselage, there was also jagged tearing and aft bending visible on the outboard tip of the right horizontal stabilizer. The empennage was approximately 1,000 feet south of the main wreckage. The geographic coordinates were 33 degrees 37.383 minutes north latitude and 111 degrees 56.195 minutes west longitude.

N6342T was located on a fairway of the Kierland golf course, south of the fourth green. The aircraft was found lying on its back and oriented on a magnetic heading of 197 degrees. A fuel spill from the right wing had discolored the grass where the green sloped downward and away from the aircraft. The left main landing gear had separated from the aircraft but was found near the main wreckage. In addition to the gear leg separating from the aircraft, the wheel and tire had also separated from the gear leg. The geographic coordinates were 33 degrees 37.876 minutes north latitude and 111 degrees 55.750 minutes west longitude.

There were gouges in the dirt and disturbed vegetation along the fairway leading up to the wreckage. Debris was also found strewn along the gouges. Two broken fiberglass antennas were found impaled in the ground at the aircraft's 12 o'clock position. Both antennas are normally mounted on the cabin roof.

The propeller spinner and left side of the engine cowling exhibited light blue paint transfers.

The wreckage of both aircraft was recovered and transported by Air Transport, Phoenix, Arizona, to their storage facility.

On November 23, 1998, a Safety Board investigator, with technical assistance from manufacturer's representatives for the airframe and engine, reconstructed two-dimensional layouts of both aircraft. N6342T was positioned with the nose directed toward the registration number on the right side of N99063. Paint transfers and imploded deformations from both aircraft were dimensionally and geometrically consistent with contact between the forward left cowling from the propeller spinner aft to the engine firewall of N6342T and the point of separation on the right side of the empennage of N99604. Moving the areas of paint transfer toward each other created relative points of contact that was 4 to 5 o'clock for N99604 and 10 to 11 o'clock for N6342T.

EXAMINATION OF N99604

Blue paint transfers were noted on the right side of the separated empennage near the registration number of N99064. The right main landing gear was separated from the strut.

Chordwise scratches were visible on the face of both propeller blades, which exhibited slight bending.

All flight control surfaces were accounted for; however, the counterweights from the left and right elevators, as well as the rudder, were detached from their respective locations. The right elevator counterweight was not recovered. The elevator halves were separated from one another at the left elevator torque tube adapter.

Both ailerons and flaps remained attached to the main wings. The flaps were visually extended to some degree. The cockpit flap selector and indicator were in agreement at 10 degrees. The flap jackscrew was not recovered.

Control continuity could not be fully established due to impact damage.

Both front seat tracks were fractured with both seats separated. Both seat frames were deformed. The left seat belt had been cleanly severed.

Both main fuel tanks were crushed and no evidence of fuel remained. The fuel lines to the engine exhibited multiple separations. The fuel sector was found in the "both" position.

The engine had separated from the airframe. The engine data plate was missing. When the rocker box covers were removed, evidence of lubrication was visible on all four assemblies. The crankshaft was rotated by means of the vacuum pump drive gear and some valve action was noted at the Nos. 2, 3, and 4 cylinders. The pushrods to the No. 1 cylinder were crushed and no valve action was visible.

The muffler was crushed.

Both magnetos sparked at all four posts when rotated by hand. The ignition harness was destroyed. The Nos. 1B, 2B, 3B, and 4T spark plugs were removed and examined. According to Champion Spark Plugs Check-A-Plug chart, all showed wear and coloration consistent with normal operation.

The vacuum pump was removed and examined. The drive coupling was in place and the shaft was rotated by hand.

EXAMINATION OF N6342T

An examination of N6342T revealed that the strobe light switch was in the "on" position. All other light switches were in the "off" position.

Each of the three propeller blades was bent and exhibited chordwise scoring and scratches. One blade was curled along its entire span, with virtually no paint remaining on the forward face. A second blade exhibited scratching on the forward and aft sides of the blade, which appeared wavy with the tip bent forward. The scratches were deeper than on the first blade. The third blade was bent slightly and exhibited some leading edge gouges. The first and second blades were

NTSB Probable Cause

the failure of the solo student pilot to acquire and maintain separation from a departing aircraft in the airport traffic pattern, which had been issued as traffic by the local controller. Also causal was the failure of the pilot and instructor in the other aircraft to maintain separation from this aircraft, which they had previously acknowledged as in sight. The inadequate D-BRITE radar repeater in the tower cab was a factor in this accident.