# N4BZ: 1991 Diehl William A S-4, registration cancelled 2013-11-04

- Type: Cancelled registration (FAA registry, deregistered aircraft)
- Cancelled: November 4, 2013
- Status when cancelled: Registration expired, pending cancellation
- Airframe: [Diehl William A S-4](https://openairdocs.org/model/diehl-william-a-s-4) (registry code 05618K4)
- Engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508)
- Data sheets: [TCDS E-274](https://openairdocs.org/tcds/E-274) (OpenAirDocs)
- Serial number: 004
- Year built: 1991
- Type of aircraft: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Experimental, amateur built
- Airworthiness date: July 16, 1991
- Certificate issued: May 5, 1994
- Last registry action: May 19, 2009
- Mode S code: A4A820
- Owner when cancelled: [Kyzer David D](https://openairdocs.org/faa-owner/KYZER%20DAVID%20D)
- Location: [Anchorage, AK](https://openairdocs.org/faa-place/AK/Anchorage)
- Owner type: Individual
- Owner's area on the map: 61.1637° N, 149.9966° W: Placed by OpenAirDocs at the center of ZIP code 99502, within about 2 miles (OpenAirDocs). The owner's mailing address, not where the aircraft was based
- The mark today: https://openairdocs.org/aircraft/N4BZ
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=4BZ
- Page: https://openairdocs.org/deregistered/N4BZ-2013-11-04

From the FAA registry file of October 29, 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 Diehl William A S-4: https://openairdocs.org/model/diehl-william-a-s-4.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 ANC08CA118](https://openairdocs.org/ntsb/ANC08CA118), Sep 5, 2008: Diehl William A S-4 (N4BZ), Galena, AK, substantial damage. Probable cause: The pilot's failure to maintain pitch control of the airplane during takeoff, and the pilot's inadequate preflight inspection of the airplane.
- [NTSB ANC99LA143](https://openairdocs.org/ntsb/ANC99LA143), Sep 11, 1999: Diehl Interstate S-4 (N4BZ), Anchorage, AK, substantial damage. Probable cause: The pilot's inadequate planning/decision, and his failure to maintain directional control of the airplane. Factors in the accident were a short runway/lake area for departure, and the pilot's…

## 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 20080905850739A](https://openairdocs.org/incident/20080905850739A), Sep 5, 2008: Diehlw S4 (N4BZ), AK, Substantial damage. (-23) [privacy data omitted] [privacy data omitted] pilot attempted takeoff during calm conditions. Pilot was able to lift only one float from water. Pilot…
- [Accident 19990911025419A](https://openairdocs.org/incident/19990911025419A), Sep 11, 1999: Amtr S4 (N4BZ), Anchorage, AK, Substantial damage. 19) On September 11, 1999, about 1145 Alaska daylight time, a float equip ped homebuilt/experiemental william diehl, interstate S-4 airplane, N4BZ, sustained…

## Other aircraft with N4BZ

- [Registered now](https://openairdocs.org/aircraft/N4BZ): Bombardier BD-100-1A10, S/N 20814, built 2019

---
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.