LAX01FA018

The Gulfstream descended from above and behind the Beech C90 and collided with it while both aircraft were on 2.5-mile final approach to the same runway. Visual meteorological conditions prevailed. The Gulfstream was on an ILS instrument approach and the Beech was on a VFR approach. Both airplanes subsequently landed without additional damage or injury to the occupants. Upon initial contact with the air traffic control tower, the Beech C90 was instructed to make a straight-in approach to the runway and was given a transponder code. The pilot miss-set the assigned code, which, due to an air traffic control computer software anomaly, caused the Beech's identifying data block to be suppressed and not available to the radar approach controller. The approach controller attempted to provide traffic advisories to the overtaking Gulfstream pilot but could not determine the Beech's type, destination, or altitude. (Altitude data became available to the controller 1 minute 14 seconds before the collision via a conflict alert message.) The controller did not issue a traffic alert to the Gulfstream crew when the Beech's altitude became known. Additionally, for unrelated reasons, the approach controller experienced frequent failures of his communication radio transmitter and was required to repeat transmissions to the Gulfstream and other aircraft. Despite the traffic point-out, in front of them 1 mile, altitude unknown, and later at short distance at a known altitude near theirs, the Gulfstream flight crew did not visually identify and avoid the Beech nor did they request radar separation services. On initial contact with the tower, the Gulfstream crew was cleared to land on the same runway the tower had previously cleared the Beech to make a straight-in approach to. When asked by the Gulfstream if there was any traffic in their vicinity, the tower replied, "nothing reported." The tower controller realized his mistake approximately 16 seconds later, however, the collision had already occurred. The Gulfstream pilot reported there were no TCAS 2 traffic advisories within 3 miles and there were no resolution advisories. The Gulfstream first officer recalled a TCAS "traffic" advisory close by at near their altitude, but no annunciation in the minute or two before the collision. With the model TCAS aboard the Gulfstream, when the aircraft's landing gear is extended, the lower TCAS antenna goes into an omni-directional mode wherein targets detected on the lower antenna only are displayed to the flight crew on the cockpit TCAS display with a text message of range and delta altitude but no bearing information. The Beech's transponder antenna was on the lower fuselage and airframe structure shielded it from interrogation by the Gulfstream's TCAS.

The Gulfstream descended from above and behind the Beech C90 and collided with it while both aircraft were on 2.5-mile final approach to the same runway. Visual meteorological conditions prevailed. The Gulfstream was on an ILS instrument approach and the Beech was on a VFR approach. Both airplanes subsequently landed without additional damage or injury to the occupants. Upon initial contact with the air traffic control tower, the Beech C90 was instructed to make a straight-in approach to the runway and was given a transponder code. The pilot miss-set the assigned code, which, due to an air traffic control computer software anomaly, caused the Beech's identifying data block to be suppressed and not available to the radar approach controller. The approach controller attempted to provide traffic advisories to the overtaking Gulfstream pilot but could not determine the Beech's type, destination, or altitude. (Altitude data became available to the controller 1 minute 14 seconds before the collision via a conflict alert message.) The controller did not issue a traffic alert to the Gulfstream crew when the Beech's altitude became known. Additionally, for unrelated reasons, the approach controller experienced frequent failures of his communication radio transmitter and was required to repeat transmissions to the Gulfstream and other aircraft. Despite the traffic point-out, in front of them 1 mile, altitude unknown, and later at short distance at a known altitude near theirs, the Gulfstream flight crew did not visually identify and avoid the Beech nor did they request radar separation services. On initial contact with the tower, the Gulfstream crew was cleared to land on the same runway the tower had previously cleared the Beech to make a straight-in approach to. When asked by the Gulfstream if there was any traffic in their vicinity, the tower replied, "nothing reported." The tower controller realized his mistake approximately 16 seconds later, however, the collision had already occurred. The Gulfstream pilot reported there were no TCAS 2 traffic advisories within 3 miles and there were no resolution advisories. The Gulfstream first officer recalled a TCAS "traffic" advisory close by at near their altitude, but no annunciation in the minute or two before the collision. With the model TCAS aboard the Gulfstream, when the aircraft's landing gear is extended, the lower TCAS antenna goes into an omni-directional mode wherein targets detected on the lower antenna only are displayed to the flight crew on the cockpit TCAS display with a text message of range and delta altitude but no bearing information. The Beech's transponder antenna was on the lower fuselage and airframe structure shielded it from interrogation by the Gulfstream's TCAS.

History of flight

On October 17, 2000, at 1551 Pacific daylight time, a Beech C90, N1801B, collided in midair with a Gulfstream Aerospace G-1159A, N162JC, while both aircraft were on 4-mile final approach to runway 16R at the Van Nuys, California, airport. Both aircraft subsequently landed safely at Van Nuys airport, and there were no injuries to the airline transport certificated pilot and two passengers aboard the Beech C90, or to the airline transport certificated pilot and two crewmembers aboard the Gulfstream G-1159A. The Beech C90 was substantially damaged and the Gulfstream G-1159A received minor damage. The Beech C90 was operated on a visual flight rules flight plan under 14 CFR Part 135 as a nonscheduled, domestic air taxi flight by Sun Quest Executive Air Charter, and had departed from Bakersfield, California, at 1520. The Gulfstream G-1159A was operated under instrument flight rules by Trans-Exec Air Service, Inc., under 14 CFR Part 91 as a positioning flight, and had departed from Reno, Nevada, about 1500.

A flight instructor, who was employed by the flight school division of Sun Quest Executive Air Charter, witnessed the midair collision from his car while driving westbound on the 118 freeway just past the 405 freeway interchange. The instructor said he just happened to look upward and his attention was attracted to two aircraft flying in close proximity, one behind the other, nearly co-speed but with the rear aircraft overtaking the aircraft in front of it. The swept wing aircraft that he later learned was a Gulfstream G3 was overtaking a smaller airplane. He couldn't judge altitude precisely; however, as he watched the two aircraft came together and the smaller airplane shuddered and then dropped down out of view behind some trees. It appeared the larger, swept-wing aircraft initiated a go-around maneuver.

Another witness observed the collision from his home in the 10,000 block of Odessa Avenue (2 miles north of the Van Nuys airport). He reported looking up after hearing a jet aircraft and seeing a corporate jet aircraft (which he identified as a "G-3", i.e. Gulfstream) making what he considered a normal approach to the airport but with a smaller, twin-engine propeller aircraft (which he identified as a "King Air") behind and to the left of the corporate jet. The King Air was about one plane length behind the Gulfstream, one fuselage diameter below the jet, and was offset to the left so that the fuselage centerline of the King Air was even with the Gulfstream's left wingtip. As he watched for the next 5 - 7 seconds, the King Air overtook the Gulfstream until the King Air was under the left wing of the Gulfstream. About the time the King Air was under the wing of the Gulfstream, the vertical gap also closed and he observed the King Air to "make some slight maneuvering motions. The wings and fuselage moved around some. The King Air then fluttered like a falling leaf. The nose pointed down and the King Air dove toward the ground with its wings rocking back and forth." The King Air then recovered and continued flying toward the airport. He heard the engines of the Gulfstream increase in power and the aircraft pulled up and banked right before continuing toward the airport. He lost sight of both airplanes about 5 - 7 seconds after the collision.

Personnel information

In an interview the day following the accident, the pilot of the Beech C90 told the Safety Board investigator that the accident flight was conducted under 14 CFR Part 135, he was the sole pilot, and there were two passengers aboard. His flying day started at 0845, and the accident flight was his fifth flight of the day. The accident flight originated from Bakersfield. He said that the flight was conducted under visual flight rules with flight following from Los Angeles Air Route Traffic Control Center (Los Angeles Center). While descending toward Newhall Pass, as the aircraft reached about 4,000 feet (msl), he was advised that radar contact was lost and to squawk 1200 and contact the Van Nuys Air Traffic Control Tower (Van Nuys Tower). He contacted the tower at Newhall Pass with (ATIS) information Papa and was issued a discrete transponder code and was told to make a straight in approach to runway 16R. He saw the airport and aligned the aircraft with runway 16R. The weather was clear, the visibility was unrestricted, and the sun angle was not a factor. The approach was made by visual reference alone. He stated he never heard anything on the radio about another aircraft that was a factor for him. When he was 3 - 4 miles out on final for 16R with airspeed of 120 - 125 knots, with landing gear down and flaps at the approach position, suddenly and unexpectedly, there was a shadow over his aircraft and the nose of the Gulfstream became visible in the top of his windshield. Immediately there was a loud "bang," his aircraft rocked violently, and he thinks it turned to the right. He looked outside and saw the damage to the left wing and asked his passengers if they were okay. They were very frightened and he said, "We are okay" to reassure them. He heard the Gulfstream transmit that they (the Gulfstream) had either encountered wake turbulence or had hit someone. He transmitted that the Gulfstream had hit them; they were going to land and to "bring out the trucks." Unbeknownst to the King Air pilot, his aircraft's radio antenna had been broken off and he could neither transmit nor could he hear the tower. He slowed the aircraft and proceeded to land. While on short final approach he received a green light from the control tower. After landing, without radio contact, he taxied with care to parking.

In an interview the day following the accident, the pilot-in-command of the Gulfstream G-1159A reported that on the morning of the accident he and the first officer had flown from Van Nuys to Reno, Nevada, as a 14 CFR Part 135 air taxi flight and dropped passengers in Reno. The accident occurred on the return flight, which was a 14 CFR Part 91 repositioning flight. His first officer was the pilot flying for the return trip. They departed Reno on an instrument flight rules (IFR) flight plan and remained IFR throughout the approach (where the accident occurred) and landing. Their arrival route was via the Fillmore VORTAC (navigational aide) and then radar vectors to the Van Nuys ILS (navigational aide) runway 16R final approach course.

The Gulfstream pilot said that as they were established on the ILS final near Magic Mountain [amusement park, 10 miles north of Van Nuys] at 5,000 - 6,000 feet msl and north of the Newhall Pass, they received a traffic advisory from Southern California Terminal Radar Approach Control (SOCAL Approach) advising them of traffic. He wasn't certain of the bearing but recalled that the traffic was generally in front of them at 2,900 feet msl. As the pilot-not-flying, he spent most of his time looking outside the aircraft for traffic. He recalled looking at the TCAS display, which was on the 5-mile scale, and noting a single target about 5 miles ahead of them. His practice in the terminal area is to keep the TCAS on short range settings to avoid clutter, so he reset the scale to 3 miles and there was no traffic displayed. As they continued the approach, with landing gear and landing flaps extended, they received a second traffic advisory from SOCAL Approach regarding the traffic ahead, and at one point, the first officer flattened the approach until they were about a dot high on the glideslope. He did not recall any TCAS annunciation. He reported that at no time did SOCAL Approach say what the traffic ahead was doing (i.e. preceding them to the airport) nor instruct them to follow anyone or offer or issue vectors for separation from the traffic.

When they were about 4 miles north of the runway threshold, on the ILS at 140 - 145 knots, he felt the aircraft roll. He didn't know what had happened b

History of flight

On October 17, 2000, at 1551 Pacific daylight time, a Beech C90, N1801B, collided in midair with a Gulfstream Aerospace G-1159A, N162JC, while both aircraft were on 4-mile final approach to runway 16R at the Van Nuys, California, airport. Both aircraft subsequently landed safely at Van Nuys airport, and there were no injuries to the airline transport certificated pilot and two passengers aboard the Beech C90, or to the airline transport certificated pilot and two crewmembers aboard the Gulfstream G-1159A. The Beech C90 was substantially damaged and the Gulfstream G-1159A received minor damage. The Beech C90 was operated on a visual flight rules flight plan under 14 CFR Part 135 as a nonscheduled, domestic air taxi flight by Sun Quest Executive Air Charter, and had departed from Bakersfield, California, at 1520. The Gulfstream G-1159A was operated under instrument flight rules by Trans-Exec Air Service, Inc., under 14 CFR Part 91 as a positioning flight, and had departed from Reno, Nevada, about 1500.

A flight instructor, who was employed by the flight school division of Sun Quest Executive Air Charter, witnessed the midair collision from his car while driving westbound on the 118 freeway just past the 405 freeway interchange. The instructor said he just happened to look upward and his attention was attracted to two aircraft flying in close proximity, one behind the other, nearly co-speed but with the rear aircraft overtaking the aircraft in front of it. The swept wing aircraft that he later learned was a Gulfstream G3 was overtaking a smaller airplane. He couldn't judge altitude precisely; however, as he watched the two aircraft came together and the smaller airplane shuddered and then dropped down out of view behind some trees. It appeared the larger, swept-wing aircraft initiated a go-around maneuver.

Another witness observed the collision from his home in the 10,000 block of Odessa Avenue (2 miles north of the Van Nuys airport). He reported looking up after hearing a jet aircraft and seeing a corporate jet aircraft (which he identified as a "G-3", i.e. Gulfstream) making what he considered a normal approach to the airport but with a smaller, twin-engine propeller aircraft (which he identified as a "King Air") behind and to the left of the corporate jet. The King Air was about one plane length behind the Gulfstream, one fuselage diameter below the jet, and was offset to the left so that the fuselage centerline of the King Air was even with the Gulfstream's left wingtip. As he watched for the next 5 - 7 seconds, the King Air overtook the Gulfstream until the King Air was under the left wing of the Gulfstream. About the time the King Air was under the wing of the Gulfstream, the vertical gap also closed and he observed the King Air to "make some slight maneuvering motions. The wings and fuselage moved around some. The King Air then fluttered like a falling leaf. The nose pointed down and the King Air dove toward the ground with its wings rocking back and forth." The King Air then recovered and continued flying toward the airport. He heard the engines of the Gulfstream increase in power and the aircraft pulled up and banked right before continuing toward the airport. He lost sight of both airplanes about 5 - 7 seconds after the collision.

Personnel information

In an interview the day following the accident, the pilot of the Beech C90 told the Safety Board investigator that the accident flight was conducted under 14 CFR Part 135, he was the sole pilot, and there were two passengers aboard. His flying day started at 0845, and the accident flight was his fifth flight of the day. The accident flight originated from Bakersfield. He said that the flight was conducted under visual flight rules with flight following from Los Angeles Air Route Traffic Control Center (Los Angeles Center). While descending toward Newhall Pass, as the aircraft reached about 4,000 feet (msl), he was advised that radar contact was lost and to squawk 1200 and contact the Van Nuys Air Traffic Control Tower (Van Nuys Tower). He contacted the tower at Newhall Pass with (ATIS) information Papa and was issued a discrete transponder code and was told to make a straight in approach to runway 16R. He saw the airport and aligned the aircraft with runway 16R. The weather was clear, the visibility was unrestricted, and the sun angle was not a factor. The approach was made by visual reference alone. He stated he never heard anything on the radio about another aircraft that was a factor for him. When he was 3 - 4 miles out on final for 16R with airspeed of 120 - 125 knots, with landing gear down and flaps at the approach position, suddenly and unexpectedly, there was a shadow over his aircraft and the nose of the Gulfstream became visible in the top of his windshield. Immediately there was a loud "bang," his aircraft rocked violently, and he thinks it turned to the right. He looked outside and saw the damage to the left wing and asked his passengers if they were okay. They were very frightened and he said, "We are okay" to reassure them. He heard the Gulfstream transmit that they (the Gulfstream) had either encountered wake turbulence or had hit someone. He transmitted that the Gulfstream had hit them; they were going to land and to "bring out the trucks." Unbeknownst to the King Air pilot, his aircraft's radio antenna had been broken off and he could neither transmit nor could he hear the tower. He slowed the aircraft and proceeded to land. While on short final approach he received a green light from the control tower. After landing, without radio contact, he taxied with care to parking.

In an interview the day following the accident, the pilot-in-command of the Gulfstream G-1159A reported that on the morning of the accident he and the first officer had flown from Van Nuys to Reno, Nevada, as a 14 CFR Part 135 air taxi flight and dropped passengers in Reno. The accident occurred on the return flight, which was a 14 CFR Part 91 repositioning flight. His first officer was the pilot flying for the return trip. They departed Reno on an instrument flight rules (IFR) flight plan and remained IFR throughout the approach (where the accident occurred) and landing. Their arrival route was via the Fillmore VORTAC (navigational aide) and then radar vectors to the Van Nuys ILS (navigational aide) runway 16R final approach course.

The Gulfstream pilot said that as they were established on the ILS final near Magic Mountain [amusement park, 10 miles north of Van Nuys] at 5,000 - 6,000 feet msl and north of the Newhall Pass, they received a traffic advisory from Southern California Terminal Radar Approach Control (SOCAL Approach) advising them of traffic. He wasn't certain of the bearing but recalled that the traffic was generally in front of them at 2,900 feet msl. As the pilot-not-flying, he spent most of his time looking outside the aircraft for traffic. He recalled looking at the TCAS display, which was on the 5-mile scale, and noting a single target about 5 miles ahead of them. His practice in the terminal area is to keep the TCAS on short range settings to avoid clutter, so he reset the scale to 3 miles and there was no traffic displayed. As they continued the approach, with landing gear and landing flaps extended, they received a second traffic advisory from SOCAL Approach regarding the traffic ahead, and at one point, the first officer flattened the approach until they were about a dot high on the glideslope. He did not recall any TCAS annunciation. He reported that at no time did SOCAL Approach say what the traffic ahead was doing (i.e. preceding them to the airport) nor instruct them to follow anyone or offer or issue vectors for separation from the traffic.

When they were about 4 miles north of the runway threshold, on the ILS at 140 - 145 knots, he felt the aircraft roll. He didn't know what had happened b