# NTSB NYC83FHM02: Dial-Thorp T-18, N11BD, Morristown, NJ, June 12, 1983

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: June 12, 1983, 12:30 local (16:30 UTC)
- Place: Morristown, NJ
- Location: 40.7993° N, 74.4149° W: Placed by OpenAirDocs at MORRISTOWN MUNI (MMU), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=40.7993&lon=-74.4149&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 35106
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC83FHM02
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/35106/pdf
- Page: https://openairdocs.org/ntsb/NYC83FHM02

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, maneuvering
  - flight/nav instruments,airspeed indicator - incorrect (contributing factor)
  - maintenance,installation - improper (cause)
  - low pass - performed, pilot in command
  - design stress limits of aircraft - exceeded, pilot in command (cause)
  - wing - separation (contributing factor)
  - flight control,flap - separation (contributing factor)
  - stabilizer - separation (contributing factor)
  - flight control,rudder - separation (contributing factor)
  - window,flight compartment window/windshield - separation (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE PLT HAD BEEN ACTIVE IN ORGANIZING AN AIR SHOW, BUT WAS NOT CONSIDERED A PARTICIPANT. HOWEVER, HIS HOME BUILT ACFT WAS ON STATIC DISPLAY. ON THE 2ND DAY OF THE SHOW, THE CHAIRMAN OF THE EVENT GAVE HIM PERMISSION TO DO A FLY-BY. SUBSEQUENTLY, HE INITIATED A PASS DOWN RWY 23 AT AN ALTITUDE OF APRX 150 FT AGL. DURING THE PASS, THE ACFT BEGAN TO PORPOISE, MADE 2 OSCILLATIONS ABOUT THE LATERAL AXIS, THEN BEGAN TO DISINTEGRATE. WHILE STILL IN FLT, THE WINGS, FLAPS, VERTICAL STABILIZER, RUDDER, RIGHT HORIZONTAL STABILIZER & PARTS OF THE CANOPY SEPARATED. THE FUSELAGE THEN ROLLED SLIGHTLY TO THE RIGHT, CRASHED & BURNED. THE ACFT WAS NOT CERTIFICATED FOR AEROBATIC FLT. THE MANUFACTURER OF THE KIT (FROM WHICH THE ACFT WAS BUILT) RECOMMENDED THE CRUISE SPEED (VNO) BE 172 MPH & THE NEVER EXCEED SPEED (VNE) BE 210 MPH. THE ACFT'S AIRSPEED INDICATOR WAS CALIBRATED IN KTS & WAS MARKED WITH THE VNO & VNE AT 170 & 213 KTS (196 & 244 MPH), RESPECTIVELY. PSEUDOEPHEDRINE & CHLORPHENIRAMINE FOUND IN PLT'S URINE.

## Aircraft

- Registration: [N11BD](https://openairdocs.org/deregistered/N11BD-2010-12-22), registration cancelled 2010-12-22, S/N 401, built 1970 (OpenAirDocs)
- Reported make and model: DIAL-THORP T-18
- Registry model: [Dial-Thorp T-18](https://openairdocs.org/model/dial-thorp-t-18) (registry code 89510BR) (OpenAirDocs)
- Registry engine: [Lycoming IO-320 series](https://openairdocs.org/engine/lycoming-io-320-series) (registry code 41509, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 401
- Airframe hours: 900
- Engines: LYCOMING IO-320-B1A 160 horsepower reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Personal, Part 91
- Operator: James Mario Dyer
- Registered owner: Registration Pending
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, July 7, 1983, 55 hours before
- Airport: MMU, Morristown, runway 23, 6,000 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 25; flight instructor, airline transport, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; toxicology performed

## Weather

- Conditions: Visual (VMC), Day
- Wind: 310° at 5 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 84 °F, dew point 63 °F
- Altimeter: 30.00 inHg
- Observed at: MMU, 1 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19830612024729A](https://openairdocs.org/incident/19830612024729A), Jun 12, 1983: Amtrth THORPT18, Morristown, NJ, Destroyed. Indicates pilot exceeded the speed on a dive and a low pass over runway. Began to porpoise and then disintegrated.

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.

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