SEA02FA083

NTSB accident investigation · Grumman G-44 · Boise, ID · May 16, 2002

Accident · Serious injuriesField investigationFinal report
Date
May 16, 2002, 17:27 local (23:27 UTC)
Place
Boise, ID
Injuries
2 serious
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N700BLGrumman G-44
Weather
Visual (VMC) · Day
Status
Completed · report April 18, 2003
Report
Approved by Office Director
Parties
FAA - FSDO
FAA report
20020516012089A
Case key
54722

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.

A blocked fuel line that resulted in fuel starvation to the engine and the pilot's failure to follow emergency procedures. A contamination of metal flakes on the fuel filter, and an inadequate annual inspection were factors.

Analysis

The pilot reported that shortly after takeoff, the right engine lost power. The pilot stated that he did not feather or secure the engine but concentrated on trying to maintain the single-engine airspeed while attempting to return to the airport. The aircraft was unable to maintain altitude and collided with trees, power lines, and a single-story residence, coming to rest on the roof. During the post-accident inspection of the right engine, the gascolator filter was found covered with metal flakes. A mass amount of the flakes were accumulated at the top end of the filter and blocking the fuel line. Visually and under magnification, the metal flakes varied in size and shape of which many were corkscrew in appearance. The fuel lines downstream of the filter contained a trace amount of fuel. The right side fuel tank was drained. The sump contained debris to include additional metal flakes, screws, washers and pink colored sealant material. The aircraft had just been signed off for the annual inspection. Several maintenance discrepancy items had been found and fixed prior to and after the sign-off. The pilot also reported that during the cross country flight, the right engine had a tendency to stall out below 1,000 rpm. The aircraft flight manual for the accident aircraft indicated in the Emergency Procedures section that if an engine failure occurs after the airplane is airborne, and single engine climb speed is attained, the inoperative engine should be feathered and secured. The single engine rate of climb chart indicated that for the given conditions at the time of the accident, the aircraft should have been able to maintain a positive rate of climb.

Factual narrative

The factual narrative1,360 words

History of flight

On May 16, 2002, approximately 1727 mountain daylight time, a Grumman G-44, N700BL, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, experienced a loss of engine power shortly after takeoff and subsequently collided with a residence located about one mile north of the Boise Air Terminal, Boise, Idaho. Visual meteorological conditions prevailed at the time and a visual flight rules flight plan was filed. The aircraft was substantially damaged and the two airline transport pilots received serious injuries. One person was at the residence and was not injured.

During a telephone interview and subsequent written statement, the pilot stated that he had recently purchased this aircraft and was flying it from Kenai, Alaska to Florida. On the day of the accident (third day of the trip), the flight originated in Bellingham, Washington, about 1200 Pacific daylight time and arrived in Boise approximately 1440. The pilot stated that 80.4 gallons of fuel was added to top off the fuel tanks. No oil was added. The pilot reported that after a pre-flight and engine start, he noted that "the right engine had a tendency to stall out below 1000 rpm, a condition that developed during the trip down from Alaska." A normal takeoff on runway 28 right was accomplished. Shortly after liftoff, the tower controller informed the pilot that one of the landing gear had not fully retracted. The pilot reported that he utilized the hydraulic hand pump and the gear fully retracted. The pilot stated that the aircraft was about 200 to 300 feet agl, when he then felt the aircraft yaw and noted that the rpm on the right engine was down from 2600 rpm (normal) to 1800 rpm. The pilot informed the tower controller that he was returning (for landing) and began a right downwind turn. The pilot reported that at this point he concentrated on maintaining 95 mph airspeed and did not attempt to feather the propeller or secure the right engine. The aircraft was unable to maintain altitude and continued to descend into a residential area. The aircraft collided with trees and power lines before coming to rest on the roof of a single story residence located at 2120 S. Hilton.

The pilot rated passenger reported that the pre-flight, start, and taxi to the runway were normal. Power was applied and 2,600 rpm was noted on both engines with 25-30 inches of manifold pressure. Both fuel pressures were in the normal range. After liftoff, the aircraft accelerated to 100 mph and a 500 foot/minute climb was attained. The flaps and gear were retracted, however, the gear did not fully retract and the pilot pumped the manual hydraulic handle a couple of times and the gear fully retracted. The passenger stated that just as the green "up" light illuminated and the gear was visually checked, the aircraft yawed to the right. The passenger noted that the rpm gage for the right engine was about 1,800 rpm, while the left engine was still indicating 2,600 rpm. The pilot leveled the aircraft at about 3,000 feet msl (about 130 feet agl) and stated that he was going to return to the airport. The tower controller cleared the aircraft for either a left or right downwind. The passenger stated that the pilot turned right and that during the turn, the airspeed started to bleed off down to 80 mph. The passenger pointed this out to the pilot which he then lowered the nose in an effort to maintain 95 mph, which is the minimum single engine airspeed. The passenger stated that initially the sink rate was high, but then shallowed out when the airspeed increased. The passenger thought that they were going to be able to level out just above the trees when he looked at the rpm gage for the right engine and noted that it was just above idle position. The aircraft then collided with the first tree, subsequently colliding with additional trees and power lines before coming to rest on the roof of a residence. The passenger stated that the pilot turned off the fuel and electricity to limit a fire hazard.

Personnel information

The pilot holds an Airline Transport Pilot certificate and is rated in single and multi-engine land and sea aircraft. The pilot was also rated in rotorcraft. The pilot reported a total flight time in all aircraft of 10,250 hours with 8,200 hours as pilot-in-command. A total flight time of 28 hours were reported in the accident aircraft make & model, with 21 hours as pilot-in-command. The pilot received his type rating in multi-engine sea aircraft on April 18, 2002, in a Grumman G-44, located in Florida. The pilot reported that all of the multi-engine sea flight time has been in the Grumman G-44.

The pilot rated passenger holds an Airline Transport Pilot certificate and is rated in single and multi-engine land aircraft. The passenger reported a total flight time in all aircraft of 9,000 hours, with 3,000 hours as pilot-in-command. The passenger reported a total flight time of 15 hours in the accident aircraft make & model, with zero hours as pilot-in-command.

Aircraft information

Maintenance records and documents found in the aircraft were reviewed. The pilot reported that he had just purchased this aircraft and had fixed several maintenance discrepancies prior to the flight from Alaska. The pilot maintained a log of daily activity dated May 4, 2002, to the day of the accident documenting each days activities. The overhauled propellers were picked-up from the overhaul shop on May 5 and installed on the aircraft May 6, 2002. The propeller logbook indicated that the sign-off for the annual inspection certifying that the propellers had been inspected in accordance with an annual inspection and determined to be in an airworthy condition was on May 8, 2002. Both engine logbooks also indicated an annual inspection sign-off on May 8, 2002. The airframe logbook indicated an annual inspection sign-off on May 9, 2002.

Additional discrepancies noted in the daily log indicated that on May 6, the batteries were found low and the engines would not start. The batteries were removed and recharged. On May 7, the engines were started but it was found that the tachometer for the left engine (number 1) was inoperative. Also the wheel bearings were making noise and it was found that the right inboard wheel bearings were dry and rusted. On May 8, the aircraft was jacked up onto a cradle and the landing gear was extended and retracted using the hand pump. On May 9, new wheel bearings were installed, and the engines were started in preparation for a flight. During the run-up a "bad mag check" was experienced and the flight was cancelled. The spark plugs were cleaned and gapped, along with installing new tires. On May 10, an exhaust leak was fixed, along with the door latch. The first flight after the annual inspection signoff was on this day. After the one hour flight, the daily log indicated "came back with #1 tach, engine mixture #2, #1 engine barrel seal, possible att gyro problem." A second 1.2 hour flight was flown later in the day. The daily log indicated "came back with flap indicator, #1 tach, tail wheel strut, left elevator fabric." The final entry for this day indicated, "Fixed everything and ran it up at 2230. Checks good." On May 11, the daily log indicated that, "tach problem is back - no fly." The entry indicated that most of the day was used trying to fix the problem with no success. A decision was made to rewire the tach, which would have to be done in Anchorage. On May 12, the daily log entry indicated that a person was found to build the wire harness. On May 13, the new wire harness was installed. A 1.5 hour flight was made. The entry indicated, "no problems." On May 14, a .5 hour flight was flown with no problems noted. At 1255, the flight departed from Kenai, Alaska, to Yakutat, Alaska, continuing on to Sitka, Alaska. A total of 5.4 hours of flight time was logged. No indication of

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.

Loss of engine powerTakeoff - initial climb
1 engine
Maintenance,annual inspection - inadequateOther maintenance personnelFactor
Fluid,fuel - starvationCause
Fuel system,line - blocked(total)Cause
Fuel system,filter - contaminationFactor
Forced landingEmergency descent/landing
Emergency procedure - not followedPilot in commandCause
In flight collision with objectEmergency descent/landing
Object - wire,transmission
Object - tree(s)
Object - residence

Aircraft

Registration
N700BL
Reported as
Grumman G-44
Category
Airplane
Serial number
1337
Airframe hours
3,810.9
Engines
Continental IO-470, 260 horsepower, reciprocatingContinental IO-470, 260 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Patrick J. Coyle
Registered owner
Aqua Air LLC.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · May 9, 2002 · 19.4 hours before
Departed
BOI · Boise, ID
Destination
EMM · Kemmerer, WY
Flight plan
VFR
Airport
BOI · Boise Air Terminal, runway 28R, 10,000 × 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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
47
Injuries
Serious
Certificate
Airline transport
Airplane ratings
Single-engine sea, Multi-engine land, Single-engine land, Multi-engine sea
Instrument ratings
Helicopter, Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
April 18, 2002
Seat
Left
Flight hours
10,250 total · 28 in this make and model · 8,200 as pilot in command · 110 in the last 90 days · 70 in the last 30 days · 4 in the last 24 hours
Role
Co-pilot
Injuries
Serious
Certificate
Airline transport
Airplane ratings
Multi-engine land
Instrument ratings
Airplane
Medical
Class 1

Weather

Conditions
Visual (VMC) · Day
Wind
330° at 8 knots, gusting 16
Visibility
10 statute miles
Lowest ceiling
None
Temperature
70 °F, dew point 25 °F
Altimeter
30.04 inHg
Observed at
BOI, 2 nm away

Docket · 36

The files NTSB released with the investigation on February 11, 2003, on NTSB’s docket system: statements, records, photos and specialists’ reports. 5.7 MB in all.

Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 - PICItem 1 · .PDF · 320 KBPilot/Operator Aircraft Accident Report, NTSB Form 6120.1 - Second PilotItem 2 · .PDF · 322 KBSupplement AItem 3 · .PDF · 152 KBSupplement BItem 4 · .PDF · 209 KBSupplement EItem 5 · .PDF · 119 KBWitness StatementItem 6 · .PDF · 76 KBAccident Location MapItem 7 · .PDF · 163 KBFlight PlanItem 8 · .PDF · 43 KBTranscript of Radio CommunicationsItem 9 · .PDF · 374 KBBoise Police Department ReportItem 10 · .PDF · 644 KBEmergency ProceduresItem 11 · .PDF · 247 KBAirframe Logbook Entry ExcerptsItem 12 · .PDF · 225 KBRight Engine Logbook Entry ExcerptsItem 13 · .PDF · 143 KBAero Maintenance Invoice ExcerptsItem 14 · .PDF · 106 KBMaintenance WorksheetItem 15 · .PDF · 58 KBRelease of Aircraft Wreckage, NTSB Form 6120.15Item 16 · .PDF · 41 KBPhoto 1. Rear view of aircraft in house.Item 17 · .PDF · 116 KBPhoto 2. Rear view of aircraft on roof.Item 18 · .PDF · 174 KBPhoto 3. Right side view of aircraft.Item 19 · .PDF · 200 KBPhoto 4. View of right engine.Item 20 · .PDF · 197 KBPhoto 5. View of left engine.Item 21 · .PDF · 175 KBPhoto 6. View of right engine after recovery.Item 22 · .PDF · 119 KBPhoto 7. Side view of right engine.Item 23 · .PDF · 124 KBPhoto 8. View of right engine with power cable entangled in spinner.Item 24 · .PDF · 87 KBPhoto 9. Close up view of power cable and damage to propeller.Item 25 · .PDF · 76 KBPhoto 10. View of right engine gascolator prior to disassembly.Item 26 · .PDF · 111 KBPhoto 11. View of right engine gascolator noting metal debris on filter.Item 27 · .PDF · 111 KBPhoto 12. View of metal debris on filter.Item 28 · .PDF · 105 KBPhoto 13. View of metal debris removed from filter.Item 29 · .PDF · 115 KBPhoto 14. View of right side gascolator bowl, filter and fuel removed.Item 30 · .PDF · 122 KBPhoto 15. View of debris in right side fuel tank sump.Item 31 · .PDF · 155 KBPhoto 16. View of metal debris, nut, screw, washers and sealant material found in right side fuel tank sump.Item 32 · .PDF · 117 KBPhoto 17. Finger screen to right engine fuel control unit with minor bits of metal shavings.Item 33 · .PDF · 83 KBPhoto 18. View of left engine and propeller blade.Item 34 · .PDF · 99 KBPhoto 19. View of left side, with right engine in background.Item 35 · .PDF · 113 KBPhoto 20. View of left engine fuel filter and gascolator bowl.Item 36 · .PDF · 88 KB

FAA reports on this event · 1

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