SEA05LA014

NTSB accident investigation · Swearingen SA226TC · Boise, ID · November 9, 2004

Accident · No injuriesLimited investigationFinal report
Date
November 9, 2004, 04:20 local (11:20 UTC)
Place
Boise, ID
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N162WASwearingen SA226TC
Weather
Instrument (IMC) · Night/dark
Status
Completed · report September 13, 2005
Report
Approved by Office Director
Parties
FAA FSDO
FAA report
20041109027639A
Case key
60520

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The NTSB’s determination of the probable cause, and any contributing factors.

The pilot's failure to maintain the required glidepath, and his failure to maintain obstacle clearance after visual contact with the runway during the instrument approach.

Analysis

During a night instrument landing system (ILS) approach to minimums, the airplane collided with the runways approach lighting system. In a written report the pilot stated that during the transition from instruments to visual references he "apparently went below the glide slope and took out two approach lights." The weather conditions recorded 16 minutes after the time of the accident were: visibility 1/4 statute mile in fog; scattered clouds at 100 feet AGL (above ground level); overcast skies at 600 feet AGL. The published decision height/altitude for the straight-in ILS runway 10R approach at Boise is 3,036 feet above mean sea level (200 feet AGL). The published minimum visibility for a straight-in ILS approach is 1/2 mile or an RVR of 1,800 feet.

Factual narrative

On November 9, 2004, about 0420 mountain standard time, a Swearingen SA226TC, N162WA, sustained substantial damage after colliding with the runway 10R approach lighting system at the Boise Air Terminal (Gowen Field), Boise, Idaho. The airplane is registered to Western Airlines LC of Boise, Idaho, and was being operated by Western Air Express as a domestic non-scheduled cargo flight under the provisions of Title 14 CFR Part 135, when the accident occurred. The commercial pilot, the sole occupant of the airplane, was not injured. Instrument meteorological conditions were reported at Boise at 0353 and 0436. The flight originated at Salt Lake City, Utah, (SLC) on an instrument flight rules (IFR) flight plan at 0310. The pilot's flight planned destination was Boise, with Twin Falls, Idaho, as an alternate.

In a written statement the pilot reported that while holding at the outer marker, the Boise tower advised him that the runway visual range (RVR) was 1800 and cleared him for the approach. The pilot stated that he "...picked up the glide slope, lowered the landing gear, and continued on normal descent. At approximately 250 AGL I picked up the glow of the rabbit, at 200 feet (3,036' [feet] on the altimeter) I looked outside and could see the rabbit and approach lights. I then continued to 100' [feet] where I could see the runway and continued to a normal landing. During my transition from instruments to visual at 2,936' [feet] I apparently went below the glide slope and took out two approach lights."

The 0436 Boise SPECI METAR observation reported weather conditions, in part, as: visibility 1/4 statute mile in fog; scattered clouds at 100 feet AGL (above ground level); overcast skies at 600 feet AGL.

The published decision height/altitude for the straight-in ILS runway 10R approach at Boise is 3,036 feet above mean sea level (200 feet AGL). The published minimum visibility for a straight-in ILS approach is 1/2 mile or an RVR of 1,800 feet.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight collision with objectApproach - faf/outer marker to threshold (ifr)
Proper glidepath - not maintainedPilot in commandCause
Clearance - not maintainedPilot in commandCause

Aircraft

Registration
N162WA
Reported as
Swearingen SA226TC
Category
Airplane
Serial number
TL-418
Engines
Garrett TPE-331, 840 horsepower, turbo propGarrett TPE-331, 840 horsepower, turbo prop
Damage
Substantial damage
Flight
Part 135
Operator
Transportation Syatems Inc, doing business as Western Airlines
Registered owner
Western Airlines
Airworthiness certificate
Standard, Normal
Departed
SLC · Salt Lake City, UT
Destination
BOI · Boise, ID
Flight plan
IFR
Airport
BOI · Boise Air Terminal /Gowen Fld/, runway 10R, 9,763 × 150 ft, asphalt

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
63
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Last flight review
June 1, 2004
Seat
Left
Flight hours
25,000 total · 5,000 in this make and model · 25,000 as pilot in command · 132 in the last 90 days · 48 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Instrument (IMC) · Night/dark
Wind
0° at 0 knots
Visibility
0.25 statute miles
Lowest ceiling
600 ft overcast
Temperature
36 °F, dew point 36 °F
Altimeter
30.03 inHg
Observed at
BOI

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.