# N521HB: 1998 Mcdonnell Douglas Helicopter 500N, registration cancelled 2023-03-04

- Type: Cancelled registration (FAA registry, deregistered aircraft)
- Cancelled: March 4, 2023
- Status when cancelled: Registration expired, pending cancellation
- Airframe: [Mcdonnell Douglas Helicopter 500N](https://openairdocs.org/model/mcdonnell-douglas-helicopter-500n) (registry code 3027374)
- Engine: [Allison 250-C20 series](https://openairdocs.org/engine/allison-250-c20-series) (registry code 03020)
- Data sheets: [TCDS H3WE](https://openairdocs.org/tcds/H3WE), [TCDS E4CE](https://openairdocs.org/tcds/E4CE) (OpenAirDocs)
- Serial number: LN084
- Year built: 1998
- Type of aircraft: Rotorcraft
- Engine type: Turbo-prop
- Airworthiness: Standard, normal
- Airworthiness date: July 31, 1998
- Certificate issued: November 7, 2016
- Last registry action: June 25, 2019
- Mode S code: A68D56
- Owner when cancelled: [City Of Huntington Beach](https://openairdocs.org/faa-owner/CITY%20OF%20HUNTINGTON%20BEACH)
- Location: [Huntington Beach, CA](https://openairdocs.org/faa-place/CA/Huntington%20Beach)
- Owner type: Government
- Owner's area on the map: 33.6790° N, 118.0130° W: Placed by OpenAirDocs at the center of ZIP code 92648, within about 2 miles (OpenAirDocs). The owner's mailing address, not where the aircraft was based
- The mark today: https://openairdocs.org/aircraft/N521HB
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=521HB
- Page: https://openairdocs.org/deregistered/N521HB-2023-03-04

From the FAA registry file of November 5, 2026, cancelled registrations. Owners' street addresses are left out. The Mode S code belongs to the N-number, not the airframe.

ADs and bulletins for the Mcdonnell Douglas Helicopter 500N: https://openairdocs.org/model/mcdonnell-douglas-helicopter-500n.md

## NTSB investigations (2)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB WPR22FA101](https://openairdocs.org/ntsb/WPR22FA101), Feb 20, 2022: Mcdonnell Douglas 500N (N521HB), Newport Beach, CA, substantial damage, 1 fatal. Probable cause: The helicopter’s encounter with unanticipated right yaw during a low-altitude, low-airspeed, tight-radius orbit. Contributing to the accident was the pilot’s distraction during the orbit, which…
- [NTSB WPR10TA025](https://openairdocs.org/ntsb/WPR10TA025), Oct 16, 2009: Mcdonnell Douglas Helicopter 500N (N521HB), Los Alamitos, CA, substantial damage. Probable cause: The flight instructor's delayed remedial action during the instructional autorotative landing, which resulted in a failure to maintain an adequate rotor rpm to avoid a hard landing.

## FAA accident and incident reports (2)

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [Accident 20220219001009A](https://openairdocs.org/incident/20220219001009A), Feb 19, 2022: Mcdonnell Douglas Helicopter 500N (N521HB), Newport Beach, CA, Substantial damage, 1 fatal. On 02/19/2022, approximately 18:30 pacific standard time, huntington Beach police helicopter, MD500N, N521HB, operating as a public aircraft, responded to a…
- [Accident 20091016053579A](https://openairdocs.org/incident/20091016053579A), Oct 16, 2009: Mcdonnell D 500N (N521HB), Los Alamitos, CA, Substantial damage. During my interview with the pilot, he stated that they were about one hour into the training flight when he decided to demonstrate a power recovery…

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.