Mcdonnell Douglas 369E and Enstrom F-28F mid-air collision near Compton, California, October 24, 1990
On October 24, 1990 at about 2:46 am local time, 2 aircraft, Mcdonnell Douglas 369E (N451DS) and Enstrom F-28F (N48HR), were involved in a mid-air collision near Compton, California. No one was hurt; 4 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
INADEQUATE VISUAL LOOKOUT BY THE PILOTS OF BOTH AIRCRAFT, WHICH RESULTED IN A FAILURE OF EACH TO SEE-AND-AVOID CONFLICTING TRAFFIC. FACTORS RELATED TO THE ACCIDENT WERE: DARKNESS, FAILURE OF THE PILOT OF AIR 28 (N48HR) TO USE HIS TRANSPONDER NEAR THE TCA, AND THE PILOT OF AIR 21 DIVERTED TOO MUCH OF HIS ATTENTION TO A MAP.
INADEQUATE VISUAL LOOKOUT BY THE PILOTS OF BOTH AIRCRAFT, WHICH RESULTED IN A FAILURE OF EACH TO SEE-AND-AVOID CONFLICTING TRAFFIC. FACTORS RELATED TO THE ACCIDENT WERE: DARKNESS, FAILURE OF THE PILOT OF AIR 28 (N48HR) TO USE HIS TRANSPONDER NEAR THE TCA, AND THE PILOT OF AIR 21 DIVERTED TOO MUCH OF HIS ATTENTION TO A MAP.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 24, 1990 · about 2:46 am local time
- Place
- Compton, California · map
- Type
- Accident · mid-air collision
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Mcdonnell Douglas 369E
- Registration
- N451DS · registry record · serial 0251E
- Damage
- Substantial damage
- Flight
- Public-use flight · general aviation rules (Part 91)
- Aircraft 2
- Enstrom F-28F · all F-28Fs on the register
- Registration
- N48HR · registry record · serial 755
- Damage
- Substantial damage
- Flight
- Public-use flight · general aviation rules (Part 91)
The NTSB's narrative for the Mcdonnell Douglas 369E final · quoted from the NTSB record
TWO HELICOPTERS WERE BEING USED IN LAW ENFORCEMENT ACTIVITIES. ONE WAS A LOS ANGELES SHERIFF'S DEPT (LASD) MCDONNELL- DOUGLAS 369E, N451DS, CALL SIGN AIR 21. THE OTR WAS A COMPTON POLICE DEPT (CPD) ENSTROM F-28F, N48HR, CALL SIGN AIR 28. WHILE IN THE LAX TCA, AIR 21 RESPONDED TO AN EMERG CALL. AFTER DEPG THE TCA, THE PLT (AIR 21) SWITCHED HIS COM RADIO TO 123.02 MHZ (COMMON FREQ FOR LAW ENFORCEMENT IN THE AREA) & ANNOUNCED HIS PSN. WHEN NO RESPONSE WAS RCVD, HE SWITCHED TO THE COMPTON UNICOM FREQ (122.9 MHZ). AT ABOUT THAT TIME, AIR 28 WAS ORBITING IN THE SAME VCNTY. THE PLT OF AIR 28 SAID HE HAD ANNOUNCED HIS PSN ON 122.9 MHZ (RQRD FREQ IN THE AREA FOR CPD ACFT) & WAS MONITORING 123.02 MHZ. THE 2 CONVERGED & COLLIDED, BUT BOTH REMAINED CONTROLLABLE & WERE LNDD FROM EMERG APCHS. BFR THE MIDAIR, THE PLT OF AIR 21 WAS HELPING HIS OBSERVER LOOK FOR A PSN ON A MAP. HE SAW AIR 28 JUST BFR IMPACT, BUT NOT IN TIME TO AVOID A COLLISION. THE PLT OF AIR 28 HAD HIS TRANSPONDER ON STANDBY, ALTHO HE WAS REQD TO BE OPERG IT, WHILE WITHIN 30 MI OF THE (GROUP 1) TCA.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The NTSB's narrative for the Enstrom F-28F final · quoted from the NTSB record
TWO HELICOPTERS WERE BEING USED IN LAW ENFORCEMENT ACTIVITIES. ONE WAS A LOS ANGELES SHERIFF'S DEPT (LASD) MCDONNELL- DOUGLAS 369E, N451DS, CALL SIGN AIR 21. THE OTR WAS A COMPTON POLICE DEPT (CPD) ENSTROM F-28F, N48HR, CALL SIGN AIR 28. WHILE IN THE LAX TCA, AIR 21 RESPONDED TO AN EMERG CALL. AFTER DEPG THE TCA, THE PLT (AIR 21) SWITCHED HIS COM RADIO TO 123.02 MHZ (COMMON FREQ FOR LAW ENFORCEMENT IN THE AREA) & ANNOUNCED HIS PSN. WHEN NO RESPONSE WAS RCVD, HE SWITCHED TO THE COMPTON UNICOM FREQ (122.9 MHZ). AT ABOUT THAT TIME, AIR 28 WAS ORBITING IN THE SAME VCNTY. THE PLT OF AIR 28 SAID HE HAD ANNOUNCED HIS PSN ON 122.9 MHZ (RQRD FREQ IN THE AREA FOR CPD ACFT) & WAS MONITORING 123.02 MHZ. THE 2 CONVERGED & COLLIDED, BUT BOTH REMAINED CONTROLLABLE & WERE LNDD FROM EMERG APCHS. BFR THE MIDAIR, THE PLT OF AIR 21 WAS HELPING HIS OBSERVER LOOK FOR A PSN ON A MAP. HE SAW AIR 28 JUST BFR IMPACT, BUT NOT IN TIME TO AVOID A COLLISION. THE PLT OF AIR 28 HAD HIS TRANSPONDER ON STANDBY, ALTHO HE WAS REQD TO BE OPERG IT, WHILE WITHIN 30 MI OF THE (GROUP 1) TCA.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record for the Mcdonnell Douglas 369E from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot, private
- Ratings: multi-engine land; single-engine land; rotorcraft: helicopter
- Flight time: 3,734 hours in all; 2,981 in this make and model; 263 in the last 90 days; 71 in the last 30 days; 3,662 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 3,168 hours
- Last inspection: 100-hour inspection, September 28, 1990; 75 hours since
- Maximum gross weight: 3,000 lb
- Seats: 4
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
- Operator: Los Angeles Sheriff Dept.
The flight
- Departed from: NONE Carson CA at 2:30 am
- Flight plan: none
- Runway 0
Weather at the time
- Light: night, bright
- Wind: from 250° at 9 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 70°F (21°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
The factual record for the Enstrom F-28F from the NTSB's investigation tables, in plain English
Pilot
- Certificate: private
- Ratings: rotorcraft: helicopter
- Flight time: 233 hours in all; 233 in this make and model; 217 in the last 90 days; 26 in the last 30 days; 148 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1,986 hours
- Last inspection: 100-hour inspection, October 17, 1990
- Maximum gross weight: 2,350 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming HIO-360-F1AD (piston); 0 hours total
- Operator: Compton Police Department
The flight
- Departed from: CPM Compton CA at 1:10 am
- Flight plan: none
- Runway 0
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.