# NTSB DCA85IA003: Boeing VC-137B-BN, Seattle, WA, October 18, 1984

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: October 18, 1984, 14:45 local (21:45 UTC)
- Place: Seattle, WA
- Coordinates: 47.539798, -122.309432 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.5398&lon=-122.3094&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 50 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB office: Major Investigations Division
- NTSB case key (mKey): 15841
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DCA85IA003
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/15841/pdf
- Page: https://openairdocs.org/ntsb/DCA85IA003

## Sequence of events

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

- Near collision between aircraft, approach - iaf to faf/outer marker (ifr)
  - communications - not possible, pilot of other aircraft (contributing factor)
  - traffic advisory - issued, atc personnel(dep/apch)
  - visual lookout - inadequate, copilot/second pilot (cause)
  - visual lookout - delayed, pilot in command (cause)
  - remedial action - performed, pilot in command
- Near collision between aircraft, cruise
  - comm/nav equipment,transmitter - inoperative (contributing factor)
  - comm/nav equipment,receiver - inoperative (contributing factor)
  - communications - not possible, pilot in command (contributing factor)
  - visual lookout - delayed, pilot of other aircraft (cause)
  - remedial action - performed, pilot of other aircraft

## Analysis (aircraft 2)

DURING ARRIVAL, A BOEING VC-137B-BN, USAF #58-6970, OPERATING AS AIR FORCE 2 (AF-2), WAS CLEARED FOR A LOCALIZER BACK- COURSE APCH. AT 1442:49, TRACON ADVISED AF-2 OF TRAFFIC AT ITS 10 O'CLOCK POSITION AT 2 MI, ALT UNKN. AT 1443:11, TRACON ADVISED AF-2 THE TRAFFIC HAD MOVED TO ITS 11 O-CLOCK POSITION AT 1-1/2 MI. AF-2 ACKNOWLEDGED BOTH TRANSMISSIONS. AT 1443:29, AF-2 ADVISED THAT THE FLT WAS CHANGING ITS FREQ TO BOEING TOWER. SHORTLY THEREAFTER, THE ACFT CMDR OF AF-2, SEATED IN THE RIGHT, SAW THE TRAFFIC, A MOONEY M20C, N6507U, ON A COLLISION COURSE. HE TOOK CONTROL & INITIATED EVASIVE ACTION. THE PLT OF N6507U WAS CRUISING AT 2,500 FT OUTSIDE THE SEATTLE TCA & DID NOT SEE AF-2, WHICH HAD CONVERGED FROM HIS RIGHT REAR AREA. THE MOONEY'S #1 RADIO WAS INOP & ITS #2 RADIO ANTENNA HAD BEEN VANDALIZED, THUS THE PLT WAS NOT IN RADIO CONTACT WITH ATC. THE LAST DIGIT/WHEEL ON HIS TRANSPONDER WAS STUCK ON '5' & CODE 1205 WAS BEING TRANSMITTED. THE TRANSPONDER HAD NO MODE 'C' ALT REPORTING CAPABILITY. ALL OF THE BACKCOURSE APCH WAS OUTSIDE THE TCA.

## Aircraft 1

- Registration: USAF (not matched to a registry record)
- Reported make and model: BOEING VC-137B-BN
- Category: Airplane
- Serial number: 17925
- Engines: P&W TF-33 turbo fan
- Damage: No damage
- Flight: Part 91
- Registered owner: 89th Military Airlift Wing
- Departed: GEG, SPOKANE, WA
- Destination: BFI, SEATTLE, WA
- Flight plan: IFR
- Airport: runway 31L, 10,000 × 200 ft, asphalt

## Aircraft 2

- Registration: [N6507U](https://openairdocs.org/aircraft/N6507U), registered now, S/N 2261, built 1962 (OpenAirDocs)
- Reported make and model: MOONEY M20C
- Registry model: [Mooney M20C](https://openairdocs.org/model/mooney-m20c) (registry code 5870208) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane
- Engines: LYCOMING O-360 180 horsepower reciprocating
- Damage: No damage
- Flight: Personal, Part 91
- Registered owner: Bruce H. Collins
- Airworthiness certificate: Standard, Normal
- Departed: S44, SPANAWAY, WA
- Destination: S88, ARLINGTON, WA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot, aircraft 1; age 33; military; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 4,602 total
- Pilot, aircraft N6507U; age 54; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 1,800 total

## Weather

- Conditions: Visual (VMC), Day
- Wind: 60° at 3 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 55 °F, dew point 37 °F
- Altimeter: 30.00 inHg
- Observed at: BFI, 8 nm away

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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