# NTSB DEN84LA158: Pitts S-2A, N80040, Boulder, CO, May 24, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 24, 1984, 15:00 local (21:00 UTC)
- Place: Boulder, CO
- Location: 40.0244° N, 105.2513° W: Placed by OpenAirDocs: center of Boulder, CO, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=40.0244&lon=-105.2513&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16385
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN84LA158
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16385/pdf
- Page: https://openairdocs.org/ntsb/DEN84LA158

## Sequence of events

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

- Hard landing, landing - flare/touchdown
  - airspeed - misjudged, pilot in command (contributing factor)
  - altitude - misjudged, pilot in command (contributing factor)
  - distance - misjudged, pilot in command (contributing factor)
  - flare - improper, pilot in command (cause)
  - recovery from bounced landing - improper, pilot in command (cause)
  - propeller system/accessories,blade - overload
- In flight collision with terrain/water, landing
  - aborted landing - initiated, pilot in command
  - go-around - attempted, pilot in command
  - aircraft performance,takeoff capability - deteriorated
  - precautionary landing - performed, pilot in command
- Main gear collapsed, landing
  - landing gear,main gear - overload

## Analysis

THE ACFT WAS OBSERVED IN A HIGH, POWER-ON APCH. ACCORDING TO A PROFESSIONAL PLT, WHO WAS A WITNESS, THE ACFT APPEARED ASIF IT WOULD LAND LONG. HE REPORTED THAT POWER WAS REDUCED AT ABOUT 50 FT AGL & THE ACFT STALLED, THEN IT LANDED HARD, BOUNCED HIGH & CONTINUED TO PROPOISE A NUMBER OF TIMES. AFTER ABOUT THE 6TH BOUNCE, THE PLT INITIATED A GO-AROUND. THE ACFT LIFTED OFF NEAR THE END OF THE RWY, BUT THE PLANE HAD INSUFFICIENT THRUST TO ATTAIN ALT. THE PLT MADE A FORCED LANDING IN A DIRT FIELD ABOUT 3/4 MI FROM THE ARPT. THE GEAR COLLAPSED DURING IMPACT & THE PROP WAS SPINNING. ABOUT 10 PROP STRIKES WERE FOUND ON THE RWY BEGINNING ABOUT 1300 FT FROM THE APCH END. THE PROP WAS CURLED BACK & 1 BLADE TIP WAS GOUND DOWN ABOUT 1 INCH.

## Aircraft

- Registration: N80040 (not matched to a registry record)
- Reported make and model: PITTS S-2A
- Category: Airplane
- Serial number: 2084
- Airframe hours: 394
- Engines: LYCOMING IO-360-A1A 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Robert Mobus
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, April 25, 1984
- Airport: IV5, Boulder Muni, runway 8, 4,100 × 75 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: front; flight hours: 128 total, 33 in this make and model, 69 as pilot in command, 4 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 75 °F

## 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 19840524018769A](https://openairdocs.org/incident/19840524018769A), May 24, 1984: Child S2APITTS, Boulder, CO, Substantial damage. Pilot allowed aircraft to porpoise several times and then attempted go around that resulted in crash.

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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