The NTSB has released
the probable cause for an April 20, 2004 Cardinal (file images
below) accident that took the lives of a pilot and passenger. The
NTSB determined the probable cause(s) of this accident as "Improper
maintenance by other maintenance personnel, and the reinstallation
of an unserviced magneto during an engine overhaul, which resulted
in the magneto malfunctioning, a loss of engine power, and the
airplane being ditched into the water."
Excerpts of the Probable Cause report are attached below.
NTSB Identification: MIA04FA076.
14 CFR Part 91: General Aviation
Accident occurred Tuesday, April 20, 2004 in Tampa, FL
Probable Cause Approval Date: 1/31/2006
Aircraft: Cessna 177RG, registration: N1910Q
Injuries: 2 Fatal.
HISTORY OF FLIGHT
On April 20, 2004, about 1134 eastern daylight time, a Cessna
177RG, N1910Q, registered to and operated by a private individual,
as a Title 14 CFR Part 91 personal flight, ditched into Tampa Bay,
Tampa, Florida. Visual meteorological conditions prevailed and no
flight plan was filed. The private-rated pilot and one passenger
received fatal injuries, and the airplane incurred substantial
damage. The flight originated in Pompano Beach, Florida, the same
day, about 0930.
An attendant at the fixed-based operator's facility at Peter O.
Knight Airport, Tampa, Florida, stated that she heard a radio
communications transmission from a pilot stating that he was 6
miles from the airport, and his airplane's engine was experiencing
roughness and backfiring. She said that she acknowledged the call,
told the pilot to use the runway of his choice, and instructed the
other aircraft to clear the traffic pattern. She further stated
that shortly after the initial call, she heard the pilot say "we're
not going to make it."
According to a nearby
fisherman, the accident aircraft was heading in a westerly
direction at an altitude of about 200 to 300 feet, about a mile to
the west of where he was fishing. The witness further stated that
he heard erratic changes in the sound of the airplane's engine,
which was continually backfiring. He said that the airplane's
engine then became silent, and at that point he noticed the
airplane make a controlled turn towards the airport.
A second witness working in the vicinity of the Port of Tampa
Bay stated that the airplane appeared to hit the water hard and it
remained afloat for about 3 to 5 minutes. A third witness that was
in a boat at the time, about a mile from the accident site stated
that he became aware of the airplane when he heard a loud smacking
noise as the airplane hit the water. He said that he proceeded to
the place where the airplane impacted the water, arriving about 3
to 5 minutes later, but at that time the airplane had sunk.
PERSONNEL INFORMATION
Records obtained from the FAA showed that the pilot held an FAA
private pilot certificate with an airplane single engine land
rating, issued on December 24, 2003. He also held an FAA third
class medical certificate, issued on January 9, 2003, with the
stated limitation "must wear corrective lenses". According to the
pilot's logbook, the pilot commenced flight training on April 22,
2003, and had accumulated a total of about 96 flight hours, 16 of
which were in the accident aircraft.
AIRCRAFT INFORMATION
N1910Q is a 1972 Cessna 177RG, serial number 177RG0310.
According to the airplane's maintenance logbook it had been given
an annual inspection on July 21, 2003, and had accumulated 4,094
flight hours on the airframe at the time of the accident. It was
also equipped with a 200 horsepower Lycoming IO 360 A1B6D engine,
serial number L-9866-51A. Records showed that the engine was
overhauled on July 21, 2003 and had accumulated about 175 flight
hours at the time of the accident. The accident airplane was also
equipped with a McCauley 2-bladed controllable pitch propeller,
serial number 754887.
METEOROLOGICAL INFORMATION
Visual meteorological conditions prevailed at the time of the
accident. The Tampa International Airport, Tampa, Florida, 1153,
surface weather observation was, wind from 260 degrees at 7 knots,
visibility 10 statute miles, scattered clouds at 4,000 feet, a
broken cloud layer at 25,000 feet, temperature 75 degrees F, dew
point temperature 51 degrees F, altimeter setting 30.17 inHg. The
Tampa International Airport is located 6 NM northwest of the
accident site.
WRECKAGE AND IMPACT INFORMATION
According to officials at the Tampa Police Department, the
accident airplane was found submerged, in a shipping channel about
one third of a mile east of the Peter O'Knight Airport, having sunk
in Seddon Channel. The airplane was upright, in position 27
degrees, 54.543 North latitude, 082 degrees, 26.520 West longitude,
in about 14 feet of water, oriented on about a northwest
heading.
The airplane was recovered about 4 hours after the accident, and
after recovery from Tampa Bay, the NTSB examined the airplane on
April 21 and 22, 2004, along with NTSB party representatives to the
investigation, which included an FAA inspector, as well as persons
from Lycoming Engines, and Cessna Aircraft Company.
The airplane was intact and there was minimal structural damage.
The Tampa Police Department divers reported that they had found the
left door in the open position, and the right door was closed.
Post-recovery examination showed no distortions to the cabin, and
when both doors were tested, the interior right-side door handle
was found to be loose, with that door disengaged intermittently
when the handle was rotated. The handles were removed and the
splines in the handle appeared to be worn. The pilot and passenger
lap belts and shoulder harnesses were found intact, unlatched, and
had remained connected to their attachment points. The seats were
also intact and attached to the seat rails.
During the cockpit examination, the landing gear lever was set
to "Up", the flap indicator read 0, and the selector showed about
25 degrees, with both flaps being visibly up. The fuel selector
valve was set to "Both", and the fuel boost pump was "Off." The
cockpit flight control positions included the throttle being
extended about 1 inch, the mixture and propeller controls being
full in, and the cowl flaps being open. Gauge reading were as
follows. The airspeed indicator showed 0 knots, the altimeter 240
feet, and the setting in the Kollsman window being 30.12 inches.
The heading indicator read 300 degrees, the vertical speed
indicator read plus 2,050; the turn coordinator was level and the
ball in the center. No. 1 VOR's Omni Bearing Selector was set on
322 and No. 2's was 357. The communications/navigation radios were
of a digital design, and No. 1 had been selected. The ADF was off
and its frequency was 740. The transponder was set at 1200. The
"Master" switch was set to "On", and the magneto switch was set to
"Both." The Hobbs hour meter read 1,505.2, the tachometer read 0,
the tachometer hour meter read 1016.82. The cylinder head
temperature needle was pegged to the right of the gauge, and the
oil temperature and pressure gauges, as well as EGT, suction and
fuel flow gauges read 0.
The main and nose landing gear were in the retracted position.
The lower cowling exhibited some aft crushing, and the leading edge
of the left stabilator was torn and the undersurface exhibited
buckling. There was a diagonal crease that extended from about the
mid section of the stabilator to the outboard aft tip. The right
hand section of the right stabilator and the corresponding section
of the trim tab exhibited signs of wrinkling. The stabilator
structure was loose in the area of the tailcone, and the tailcone
fairing was wrinkled.
There was minimal damage associated with the ailerons, flaps,
and rudder, and flight control surfaces had remained attached to
the airframe. Control cable continuity was established to each of
the flight control surfaces. The flap's jackscrew was extended 3.3
inches, consistent with the flaps being extended less than 10
degrees. When battery power was momentarily applied to test the
flaps, they started to extend.
Examination of the left and right wing fuel tanks revealed blue
liquid about 1.25 inches from the tabs. Approximately four gallons
of saltwater and 15 gallons of blue fuel were drained from the
right wing, and no fuel was drained from the left fuel tank.
An officer with the Tampa Police department stated that the fuel
selector switch had been moved from "both" to "off" during
recovery. When examined, fuel was observed to flow from the line
from the fuel tanks to the fuel strainer when the fuel switch was
in all positions other than the "Off" position. Water and some
debris were found in the fuel strainer, however the fuel screen
contained no debris. In addition, the fuel injector inlets as well
as the main fuel strainer were clean, and there was evidence of
fuel in the fuel flow divider
Water was present in the oil system, about 1 1/2 quarts of oil
remained in the sump. The oil suction screen and oil filter were
clean, the oil cooler was secure, and the oil cooler hoses were
intact and secure.
The right muffler exhibited an area of chaffing that extended
part way around its circumference, and when the muffler was removed
and examined and its internal passages were found to be clear. The
air box was clear, the alternate air door was secure, and the
induction air filter was intact. No induction or exhaust
obstructions were found.
The propeller spinner had been dented on one side, and the
propeller remained attached to the engine and exhibited little to
no damage. The propeller governor was secure on the case, and the
drive gear was intact and rotated freely
During examination of the engine and accessories, hoses were
noted to have aged, and the fuel hose, in addition to being old and
brittle, was long, and had significant bending to accommodate its
length. On its route from the engine-driven pump to the fuel
control unit, the fuel hose was noted to be in contact with the No.
4 cylinder's cooling fins. When the hose was detached about a
trickle of fuel was recovered at the fuel control end of the line.
When the propeller was rotated fuel was observed to flow consistent
with there having been no blockages
Control positions at the engine showed the mixture was 1/4 inch
from full rich, the throttle was 1/4 inch from full open, and the
propeller was at low pitch. The engine was partially disassembled
and the propeller, valve covers, and accessories were removed.
Continuity of the valve system and drive train was confirmed to all
cylinders and to the back of the engine. In addition, all four
cylinders produced compression. The spark plug electrodes exhibited
moderate wear, the gaps were normal, and salt-water intrusion was
noticed. The ignition harness had incurred saltwater damage, and
was in a tattered and worn condition.
All engine accessories to include the starter, alternator, and
vacuum pump were found affixed to the engine, and when they were
removed and examined, they displayed no anomalies. The muffler's
internal passages were clear and exhibited a light grey color.
There was some chaffing on the right side muffler can, but no leaks
were observed to exist in the system.
The engine lubrication system had suffered water intrusion, and
most of the oil had been displaced, leaving only about one and a
half quarts in the system, and however system integrity was
maintained to include the oil suction screen, oil filter, and
associated hoses that exhibited no anomalies.
TESTS AND RESEARCH
On May 4, 2004, the NTSB examined the Bendix fuel flow divider
installed on the accident airplane. During the course of the
examination the Fuel Flow Divider was noted to have not been
maintained and updated with the latest diaphragm change, as
specified in Bendix Fuel Systems Service Bulletin RS-86, dated
December 23, 1983. Examination of the spider/fuel nozzles revealed
a fuel flow consistent with manufacturer specifications, and no
anomalies were noted.
Under the supervision of an FAA Inspector, on August 18 and 19,
2004, a detailed examination of the magneto installed on the
accident airplane was performed at Teledyne Continental Motors,
Mobile, Alabama. The examination revealed that the magneto's cam
did not have proper lubrication, and the magnetos' points had
seized.
The accident airplane was equipped with a Teledyne Continental
Motors single-drive dual magneto, part number 10-38255-1, serial
number 22402. The magneto was originally manufactured in August
1978 and records indicate that Electrosystems, Inc., last
overhauled it in October, 1997. The magneto harness had visible
areas of wear. The magneto cover was removed and it was noted that
the points had little or no movement. According to the aircraft's
engine logbook, the magneto was reinstalled on July 21, 2003, the
time in which the engine was overhauled, however, no records were
found to indicate that a magneto overhaul had been performed.
According to the Teledyne Continental Motors Service Bulletin
SB643B dated February 25, 1994, "...magnetos must be overhauled
when the engine is overhauled. ...Magnetos must be overhauled or
replaced at the expiration of five years since the date of original
manufacture or last overhaul, or four years since the date the
magneto was placed in service, whichever occurs first, without
regard to accumulated operating hours." In addition, Lycoming
Mandatory Service Bulletin SB240R, dated November 10, 1999,
specifies mandatory parts replacement at overhaul and during repair
or normal maintenance.