HISTORY OF FLIGHT
On February 15, 2000, at 1227 eastern standard time, a Piper PA-28-161, N8447Y, encountered vortex turbulence, cart-wheeled and crashed while conducting a touch-and-go operation on runway 2 left (2L) at the Dekalb Peachtree Airport (PDK), Chamblee, Georgia. The aircraft was operated by American Air Flight Training, and flown by the student pilot under the provisions of Title 14, CFR Part 91, and visual flight rules. Visual meteorological conditions prevailed and no flight plan was filed for the local solo flight. The student pilot sustained fatal injuries, and the airplane was destroyed. The flight originated from the PDK Airport in Chamblee, Georgia, about 1115 the same day.
According to witnesses, N8447Y was passed by N5QZ, a Sikorsky S76 helicopter, while on short final to runway 2L. The helicopter then made a low approach over runway 2L, slowing to a hover over or just past the departure end of the runway. According to witnesses, shortly after becoming airborne following the touch-and-go, N8447Y rocked from side to side, then rolled left until the wingtip struck and ground, and the aircraft cart-wheeled and crashed. The PDK Airport has a Federal Aviation Administration air traffic control tower that was open and in contact with both the helicopter and N8447Y at the time of the accident.
The pilot of N8447Y was operating in the local traffic pattern of PDK, conducting repeated landing and takeoff operations in a left-hand traffic pattern for runway 2L. There were numerous other aircraft in the 2L pattern, as well as arrivals and departures operating on both runway 2L and 2R.
According to FAA transcripts of tower communications, at 1221:45, Option 63, a Beech-jet called PDK tower and reported being on a left base for runway 2R. The local Controller cleared Option 63 to land on runway 2R, and advised the pilot of numerous aircraft in the pattern for runway 2L. The pilot of Option 63 acknowledged the landing clearance and the traffic information. The Local Controller reported the wind at that time as 230 degrees at 4 knots.
At 1222:04, the pilot of Sikorsky N5QZ called the tower, advising that he was 8.7 miles south-southwest of the airport for landing. The Local Controller asked N5QZ to "ident" and after observing the "ident-reply" on the tower radar display, instructed the pilot to join a 3 mile final for runway 2L. The pilot acknowledged. At 1222:51, The Local Controller cleared N8447Y for a touch and go landing on runway 2L, and advised the pilot that he was number 3 behind a Cessna. The pilot of N8447Y acknowledged. At 1223:24, the Local Controller asked the pilot of N5QZ, if he was intending to park in the northeast ramp area. The pilot replied that he was, and the Local Controller instructed him to continue for runway 2L and expect sequencing momentarily.
At 1224:28, the Local Controller transmitted, "N5QZ number two runway 2L follow cherokee on a one and a half mile left base, do you have that traffic." The pilot of N5QZ replied, "Quebec Zulu that's in sight number two." At 1225:17, the Local Controller cleared N8447Y for a touch and go on runway 2L, and advised the pilot of traffic to his right landing on the parallel runway. The pilot of N8447Y reported the traffic in sight. At 1225:24, the Local Controller transmitted, "Option sixty three contact ground point six off the runway no delay please good day." At 1225:39, the Local Controller cleared N5QZ for a low approach to runway 2L, and instructed the pilot to continue to the intersection of taxiways Juliet and Alpha after the low approach. The Local Controller also advised N5QZ's crew that a Beech Jet (Option 63) was turning off of runway 2R at the time. The pilot of N5QZ replied, "Quebec Zulu understand and ah we'll go behind him." At 1226:15, the ground controller instructed Option 63 to hold their position for landing helicopter traffic, and the crew responded, "okay we'll hold right here option sixty three."
At 1226:22, the Local Controller transmitted, "five Quebec zulu continue sir and november four seven yankee you can continue for runway two left cleared touch and go, the helicopter was supposed to follow you, you are cleared touch and go that traffic's low approach landing Juliet and alpha." The pilot of N8447Y responded, "four seven yankee ah touch and go." At 1227:15, the Local Controller transmitted "(unintelligible) all aircraft in the pattern go around fly east of the airport. At 1227:25, the Local Controller instructed N5QZ to proceed to the ramp, advising that there was an emergency in progress and cautioning the pilot that fire vehicles would be in the area. Airport rescue and firefighting crews were notified of the crash by the ground controller and responded to the scene immediately.
PERSONNEL INFORMATION
The pilot of N8447Y was a 36-year-old student pilot. The flight school's records indicated that the student pilot had accumulated 43 hours total flight time, 39 of those hours with an instructor. The student pilot had accumulated four (4) hours solo time including the accident flight with appropriate endorsements in his logbook and on his student pilot certificate. The pilot's first solo was on November 30, 1999. The pilots most recent third class medical/student pilots certificate was issued on June 3, 1999, with no waivers or limitations.
The first pilot of N5QZ, an Airline Transport Pilot (ATP), with ratings in airplane single engine land and sea, airplane multi-engine land and sea, rotorcraft-helicopter. Additionally, the pilot was type rated in the A-109, DA-20, DC-3, L-1329 and the LR-Jet. The pilots most recent first class medical certificate was issued on September 24, 1999, with no waivers or limitations.
The second pilot of N5QZ, an ATP with ratings in airplanes multi-engine land, and had a type rating in the CE-500. Other certificates included commercial ratings in airplane single engine land, rotorcraft-helicopter and instrument helicopter. The pilots most recent first class medical certificate was issued on November 16, 1999, with a limitation to wear corrective lenses while exercising the privileges of his airman certificate.
AIRCRAFT INFORMATION
The Piper PA-28-161, was a four (4) seat, single engine airplane, powered by a Lycoming O-360-D3G, engine, and was registered to American Air Flight Training, Inc. On December 17, 1999, the airplane received a 100 hour inspection, with no major discrepancies noted. The logbooks revealed that the airplane had accumulated a total time of 10,453.2 hours, at the time of the accident.
The 1992, Sikorsky S-76B, N5QZ, was an 8 seat, twin engine helicopter, powered by two Pratt & Whitney 980 horsepower PT6 series turbo-shaft engines with a certified gross weight of 11,700 pounds. The helicopter was registered as a standard transport helicopter to Kuse Enterprises Inc. Atlanta, Georgia.
METEOROLOGICAL INFORMATION
Visual meteorological conditions prevailed at the time of the accident. The reported weather at KPDK at 1253, was winds variable three knots, visibility 10 statute miles, sky clear, temperature 15 degrees Celsius, barometric pressure was 30.21 inches of mercury.
WRECKAGE AND IMPACT INFORMATION
Examination of the accident site found that the airplane's left wingtip contacted the left side of runway 2L, about 450 feet short of the end of the runway. The wing tip scraped the asphalt for about 15 feet, then the nose of the airplane impacted the ground as evidenced by two distinctive propeller strikes approximately eight inches apart. The airplane continued to cart-wheel until striking the right wing which separated at impact. The airplane continued, separating the left wing and coming to rest inverted 189 feet from the initial impact point, on a 340 degree heading. A fire started in the engine area and was extinguished by airport rescue and fire fighting (ARFF) personnel with minimal fire damage.
The left wing was separated from the fuselage and displayed heavy impact and scrape marks in the wingtip area. The aileron section was found in place with the stop bolts undamaged and secure. The aileron control rod was found separated at the aileron rod end. The separation was examined and appeared to be from overload. No pre-impact damage was noted. Both control cables were found secure to the aileron section but were separated near the wing root. Both separations were examined and found to be typical of tension overload. The aileron was in place but displayed significant impact damage especially near the outboard end. The flap was separated and displayed impact damage. The flap control torque tube on the left side was found in the retracted position. The fuel tank was intact and the fuel petcock was in the locked (closed) position. The landing gear was in place and appeared undamaged.
The right wing was separated from the fuselage and displayed damage in the wingtip area. The aileron section was found in place with stop bolts undamaged and secure. The aileron control rod was found separated at the aileron rod end. The separation was examined and appeared to be from overload. No pre-impact damage was noted. Both control cables were found secure to the aileron section but were separated near the wing root. Both separations were examined and found to be typical of tension overload. The aileron was in place but displayed damage near the outboard end. The flap was in position and displayed damage. The flap control torque tube on the right side was found in the retracted position. The fuel tank was intact and the fuel petcock was in the locked (closed) position. The landing gear was in place and appeared undamaged.
The horizontal stabilator was in place and secure. Both the stop and hinge bolts were in place and the stabilator was free to move through full travel. The counter weight and tube were in place. Both stabilator control cables were secure to the tube. Cable was found still attached to the balance tube and both 'T' bar attach points. The trim drum showed about 5/8 inch or 3 threads upper extension. The vertical stabilizer was in place and displayed no significant damage. The rudder was secure at all hinge points and free to move through full travel. Stop bolts were in place, undamaged and secure. Both control cables were secure to the attach points and verified to the forward rudder tube attach points.
The fuselage displayed heavy impact to the left front. The engine was pushed aft and upward. The windshield was missing and the cabin door separated. Both cockpit seats were secure on the seat tracks and showed no deformation. Headrests were noted. All front seat belts and attach points were in place and secure. The left side shoulder harness was connected to the seat belt. Rescue personnel reportedly unfastened the pilot's seat belt during extrication. The rear seat was in place and secure. Baggage straps were found in good condition, in place and secure.
The propeller was found attached to the engine with numerous marks noted along the entire leading edge of both blades. Chordwise and diagonal scratches were evident on both sides of the propeller blade. One blade displayed an 'S' bend near mid span. Several attach bolts were still in place and mounting holes showed elongation. Due to witness statements and impact marks on the propeller, an in-depth examination of the engine was not done.
MEDICAL AND PATHOLOGICAL INFORMATION
A post mortem examination of the pilot was conducted by the Office of the Medical Examiner, Dekalb County, in Decatur, Georgia. On March 30, 2000, a toxicology examination of the pilot was conducted by the FAA Toxicology Research Laboratory. The examination revealed no evidence of drugs, ethanol, cyanide, or carbon monoxide, in the blood, vitreous or urine.
S76B PILOT STATEMENTS
According to the first pilot, who was acting as the pilot-in-command of the Sikorsky S76B Helicopter, N5QZ, they had made contact with the Dekalb Peachtree tower 9.8 miles to the west/southwest of Peachtree Dekalb Airport at approximately 12:35, asking for permission to land. After having received the ATIS information, the tower issued a request for notification when they were established on a three-mile final to runway 2L, at which time they would be given a sequence to land. After reaching about 3 nautical miles at 2,000 feet AGL, they turned final for 2L, and were given clearance to over-fly the runway and then land at the intersection of taxiways A and J. He said that at the approach end of runway 2L, he cleared the runway visually, and they proceeded down the runway, decelerating from 80 to 60 knots, indicated airspeed. Just before reaching the end of the runway, he said that he heard the controller say "The helicopter was supposed to follow you." Within five seconds, the controller issued instructions to "a helicopter" or aircraft to deviate from their flight path. Since they were in the process of clearing the runway in an air taxi, he did not feel that these instructions were directed towards them. He stated that they continued their approach and because the Beechjet was very close to the intersection of taxiways A and J, he chose to land on the taxiway just south of taxiways A and J, and then ground taxi clear of the parallel taxiway. Prior to clearing the taxiway, he heard the controller say that there had been an accident. Without responding to the tower, we cleared A and J taxiways immediately and positioned themselves on the southern power company's ramp apron to facilitate the fire rescue vehicles. After the fire rescue vehicles passed their location, they continued taxiing to the ramp where the helicopter was shut down and subsequently put into the hangar. At that point in time, they suspected that they had been involved in the incident.
The second pilot stated that they were returning to the Peachtree Dekalb Airport. He said that he was at the controls from the co-pilot's side. He said they made contact with Peachtree Dekalb Airport Tower at approximately 9 to 10 miles from the airport, and the tower instructed them to establish themselves on a three-mile final for runway 2L. He did that and turned final to 2L at about 3 miles out, and started to decelerate the helicopter, and started to configure the helicopter for landing. The tower instructed them to do a low approach over runway 2L, and to land at the intersection of A and J taxiways. He said he made the approach to the runway, descended and continued to decelerate to comply with the tower instructions, and he believed that near the last one-third of the runway, he heard some tower transmissions instructing one aircraft to make an immediate left turn and to have another helicopter do a go-around. He did not recognize the call sign of the aircraft that was told to make the left turn. When he heard the other transmission from the tower for helicopter go-around, he did not know who the tower was referring to. By that time, he was at the end of 2L and was amending his approach slightly to the left to complete the landing at the intersection. The tower declared an emergency and told him to continue to land, and at that time, the first pilot took over the controls and completed the landing. We taxied off the taxiway to a ramp to make room for the fire trucks that were coming towards us.
WITNESS STATEMENTS
There were several eyewitnesses to the accident. Many of which stated that they observed the helicopter pass N8447Y on the right while on short final. The helicopter then proceeded down runway 2L, and come to an abrupt stop at the end or just past the end of the runway in a hover about 50 to 100 above the ground. Those same witnesses said they saw N8447Y, takeoff after landing and at about 50 to 100 feet above the ground they observed the airplanes wings rock from right to left and impact the runway with the left wing tip and cart-wheel, coming to rest in the grass inverted. Several of the witnesses stated that they believed that the pilot of N8447Y was attempting to maneuver around the helicopter. Some of the witnesses stated they believed that the airplane was caught in the helicopters wake turbulence. One witness who was piloting N4943G, a Cessna 172, stated that he was on final approach to runway 2L, following N8447Y, when the accident occurred. He stated that he observed a Sikorsky Helicopter pass N8447Y, a Piper Cherokee on short final. He said that he was a private pilot with about 600 hours total time, and that he had been out practicing maneuvers for his commercial certificate.
The pilot of N4943G, stated that he was in the pattern about mid-field on downwind for runway 2L, when the tower called him and told him that he was to extend his downwind and follow the helicopter that was about two miles out at 1600 feet. The pilot acknowledged the instructions and observed a Cherokee on short final and the Sikorsky Helicopter pass him on the right very fast on about a one half mile final and then slow down. The pilot of N4943G, had turned base to final and was now following the Cherokee N8447Y. The pilot thought that the helicopter was going to land on runway 2R, when he saw the helicopter cut in front of N8447Y near the end of runway 2L and stop.
The pilot said he observed the Cherokee N8447Y, land about 200 to 400 feet down from the approach end of runway 2L, roll awhile and proceed to rotate and takeoff again. Shortly after the Cherokee rotated, the airplane went into what he described as a "VMC stall" and impact the runway with the left wing tip and then cartwheel. The pilot stated that from his vantage point he believed that the Cherokee had gotten into the rotor wash of the helicopter.
AIR TRAFFIC CONTROLLER INTERVIEWS
According to the Air Traffic Control Cab Coordinator, who was working the flight data position as well, stated that her duties included coordination between the local and ground controllers, coordination with Atlanta Terminal radar Approach Control, managing the Automatic Terminal Information Service (ATIS) broadcast, augmentation of the Automatic Surface Observation System (ASOS) weather reports as necessary, and distribution of flight strips to the other controllers. She characterized her workload as "busy", because the local control position was working lots of pattern traffic along with several instrument flight rules (IFR) arrivals. Additionally, she was managing the flight strips for the Local Controller (LC) position, monitoring his traffic, providing him with flight strips as necessary, and coordinating between the ground and local controllers. She described the workload at the local controller position as busy and unusually heavy for that time of day. The traffic levels were high enough that she was beginning to consider whether opening a second local control position would be advisable.
N8447Y had been in the pattern "for a while", but she was not sure for how long. The local controller had five strips marked for touch and go aircraft, including N8447Y. The pilot of N8447Y was very responsive, used good communications practices, and responded well to traffic calls. The local controller seemed to be communicating well with the aircraft around the airport. The Cab Coordinator stated that she heard N5QZ call the tower from the southwest and request parking at the northeast ramp area, at which time she started coordinating the helicopter's arrival with the ground controller, telling him that the helicopter would be landing at the intersection of the J and A taxiways. The ground controller asked her to advise him when N5QZ was one mile from the airport. The Cab Coordinator looked out the window toward runway 2L's final approach course and saw both the helicopter and N8447Y on final for runway 2L, with the helicopter on N8447Y's right. She believed that Option 63 a Beechjet was on final for runway 2R as well, but was not sure. When she saw two aircraft coming toward runway 2L, the Cab Coordinator started coordinating with ground control to see if they could allow N5QZ to sidestep to taxiway A and land there. She stated that the ground controller seemed agreeable to that plan, so she advised the local controller that ground control would release taxiway A if necessary. She said that she did not recall a specific acknowledgment from the local controller that he had understood the message. She stated that she looked at the approaching helicopter and PA28 again, and believed that they were "together" on approximately a 3/4 mile final for runway 2L and at the same altitude. She told the local controller that both aircraft appeared to be together, but did not get a response. She again asked the ground control to release taxiway A, and was told that it was available if needed by the local controller. When she turned back to look at the runway, the helicopter appeared to be ahead of the PA28, but seemed to be "dilly-dallying" over the runway as if the pilot was unsure about what to do. The cab coordinator overheard the local controller tell the helicopter to give way to Option 63, so she went back to ground controller to tell him them about the change in plans. Option 63 was holding on taxiway J short of taxiway A, and did not move until after the accident. N8447Y did a touch and go behind the helicopter, and appeared to loose control after rocking back and forth at low altitude. The aircraft crash into the grass near the runway and broke up.
When asked if the local controller knew that the ground controller had stopped Option 63 on taxiway J, the cab coordinator said that as far as she knew the local controller was unaware of it. When the accident occurred, the cab coordinator called the fire department to respond.
The cab coordinator did not believe that the helicopter crew saw N8447Y, as she saw no indication that they were attempting to follow the PA28. She thought that they may have seen some other aircraft: there was a Cessna ahead for runway 2L, and a Seneca arriving on runway 2R. Before the crash, N8447Y looked like the pilot was trying to avoid the helicopter. She thought the left turn, right before impact might have been evasive action. The pilot quickly lost control, and she called the fire crews to respond. The helicopter was never told to sidestep to land on taxiway A. N5QZ's last clearance was to make a low approach to runway 2L, follow Option 63, and land at the intersection of taxiways J and A.
According to the Local Controller, at the time of the accident he believed there were five aircraft in the pattern doing touch and go practice, plus other arrivals landing at PDK. He believed that two or three of the aircraft were PA28 Cherokees, but that N8447Y was the only one in the pattern. N8447Y had been in the pattern at least 20 minutes. N8447Y was showing a normal transponder target on the DBRIGHT, and had no apparent problems. The local controller characterized his workload as moderate.
The local controller stated that the helicopter pilot called the tower and reported that he was 5 1/2 miles southwest of the airport, near downtown Atlanta. The helicopter was a regular user of the airport and the local controller had worked with it several times before, and said that it was in and out of the airport a lot. In response to the initial call the local controller issued the wind and altimeter setting, instructed the pilot to plan on a straight-in arrival to runway 2L, and informed the pilot to expect to be sequenced momentarily.
When the helicopter reached approximately a three mile final for runway 2L, the local controller stated that he told the pilot that he would be number three for the runway following a Cherokee (N8447Y) on a one and one half mile left base. The local controller saw the helicopter on the DBRIGHT, and believes it did a modified straight-in approach. The helicopter pilot reported the Cherokee in sight, and the local controller stated that he then moved on to other duties. Later, he looked at the runway 2L final approach course and saw both N8447Y and the helicopter on approximately a 1 mile final, with the helicopter slightly ahead and to the right of N8447Y at about the same altitude. He said the helicopter was passing N8447Y. He then cleared the helicopter for a low approach, and then told N8447Y to followed the helicopter, and cleared him for a touch and go. The local controller believed at the time that N8447Y was about 1/3 to 1/2 mile behind the helicopter, and stated that he was applying the 3000 foot runway separation rules between the two aircraft. He said that if that did not work out, he intended to give N8447Y a go-around.
The local controller stated that he instructed the helicopter crew to execute a low approach to runway 2L, and then follow the Beechjet Option 63, on taxiway J. He stated that the helicopter did not follow his instructions, instead it left the runway at approximately the 2L/34 intersection, sidestepping to taxiway A, and following A to the taxiway J intersection where it landed. The local controller expected the helicopter to continue up runway 2L as cleared, turn in behind the Beechjet, and follow it to the J/A intersection. Instead the helicopter landed in front of the Beechjet.
The local controller believed that the cab coordinator was aware that his plan was to land the helicopter behind the Beechjet. He did not specifically coordinate the change to land the helicopter at taxiway J after it overflew taxiway A, but overheard the cab coordinator talking to the ground controller about it so he assumed it was coordinated.
When the helicopter and N8447Y were on final approach to runway 2L, Option 63 was on runway 2R and talking to the ground controller. Option 63 had landed about one mile ahead of the helicopter after completing a left base for runway 2R.
The local controller stated that he believed that the helicopter crew saw N8447Y, and that the pilot of N8447Y saw the helicopter. When the helicopter crew was issued their number three sequence, they were about three miles south of runway 2L, and N8447Y was about 1.5 miles west of the runway on a left base leg. N8447Y was still on base when the local controller first cleared the pilot for a touch and go. The local controller also said that when he cleared the helicopter for a low approach, in his judgment it was clearly spaced behind N8447Y. N8447Y turned onto the final approach course about one mile from the runway 2L threshold. Later he saw the two aircraft together on final, the DBRIGHT showed their altitude as 1600 feet mean sea level. At that time he still planned to have the helicopter follow the Beechjet along taxiway J and land at the J/A intersection. At 12:26, the local controller informed the pilot of N8447Y that the helicopter was supposed to have followed him, and reiterated the touch and go clearance. The local controller stated that the helicopter was 1/3 to 1/2 mile ahead of N8447Y, and had returned to the centerline of the runway. He believes that the helicopter was air taxiing along taxiway A north of taxiway H when N8447Y crashed.
The local controller said that he believes that the helicopter and N8447Y were at least 1/2 mile apart at all times while operating on runway 2L, he did not believe that the required separation was lost at any time. Furthermore, he believed that the accident may have resulted from a combination of wake turbulence or rotor-wash being blown back on to the runway after the helicopter sidestepped to taxiway A, and the student pilots inexperience. When asked why he thinks the helicopter sidestepped to taxiway A without being told to do so, he said it might have been because the crew saw the Beechjet ahead of them on taxiway J. When asked if any procedures or rules needed to be changed in order to prevent a reoccurrence, he stated that there may be a need to provide mandatory wake turbulence advisories to small aircraft operating near or behind helicopters.
