National Transportation Safety Board Public Report on the John
Denver accident
LAX98FA008
HISTORY OF FLIGHT
On October 12, 1997, shortly after 1728 Pacific daylight time,
an experimental Adrian Davis Long EZ, N555JD, crashed into the
Pacific Ocean near Pacific Grove, California. The airplane was
destroyed and the pilot, the sole occupant, received fatal injuries.
The accident occurred during a local, personal flight, visual
meteorological conditions and no flight plan was filed.
An aircraft maintenance technician who assisted the pilot in removing
the airplane from a hangar before the accident flight stated that
he observed the pilot perform a preflight check that took about
20 minutes. He stated that the pilot borrowed a fuel sump cup
and drained a fuel sample to check for contaminants. He did not
observe whether the pilot visually verified the quantity of fuel
aboard the airplane. He did not see the pilot check the engine
oil level.
The technician stated that he and the pilot talked about the inaccessibility
of the cockpit fuel selector valve handle and its resistance to
being turned. The handle was located behind the pilot's left shoulder.
They attempted to extend the reach of the handle, using a pair
of vice grip pliers. But this did not solve the problem as the
pilot could not reach the handle. The pilot said he would use
the autopilot inflight, if necessary, to hold the airplane level
while he turned the fuel selector valve.
According to the maintenance technician, the pilot declined an
offer of fuel service. The pilot told him that he would only be
flying for about 1 hour. The pilot then got in the airplane and
proceeded with his preflight duties, including checking the operation
of the control surfaces According to the technician, he observed
the fuel selector handle in a vertical position. (see Aircraft
Information section for a discussion of fuel selector handle ).
The technician said that he went into the hangar to put away his
tools, and he heard the engine start; however, it soon quit. He
walked out of the hangar and observed the pilot turned in his
seat to the left, toward the fuel selector location. The technician
said he believes that the pilot changed the fuel selector and
restarted the engine.
A review of the Monterey Peninsula Airport Air Traffic Control
Tower (ATCT) tapes revealed that the pilot contacted ground control
at 1702 and obtained a taxi-for-takeoff clearance from the hangar.
At 1709, the pilot contacted the local controller, reported ready
for takeoff on runway 28, and requested to stay in the traffic
pattern for some touch-and-go landings. He was subsequently cleared
for takeoff at 1712, and performed three touch-and-go landings
before departing the traffic pattern about 1727. At this time
the controller asked the pilot to recycle his transponder code,
and the pilot did so. The ATC tapes revealed no recorded distress
calls from the pilot, and the pilot did not indicate any aircraft
or engine malfunctions. A certified audio cassette re-recording
of the transmissions between the accident airplane and the Monterey
ATCT local control position was sent to the Safety Board's audio
laboratory for analysis. The radio transmissions were examined
on an audio spectrum analyzer in an attempt to identify any background
sound signatures that could be associated with either the engine
or the propeller. Analysis of nine transmissions between 1714
and 1728:06 showed engine speed harmonics between 2,100 and 2,200
revolutions per minute (rpm). At the last radio transmission attributed
by the Federal Aviation Administration (FAA) to the accident aircraft
(at 1728:06), the measured frequency was to 2,200 rpm. A copy
of the laboratory report is attached.
Twenty witnesses to the accident were interviewed. Some of the
witnesses observed the airplane descend into the ocean near Point
Pinos approximately 150 yards off shore, where the water is 30
feet deep. Depending on where they were when the crash occurred;
four of the witnesses indicated that the airplane was originally
heading west; five of them observed the airplane in a steep bank,
with four of those five reporting the bank was to the right (north).
Twelve witnesses saw the airplane in a steep nose-down descent,
and 6 of them saw the airplane hit the water. Witnesses estimated
the airplane at 350 to 500 feet over the residential area while
heading toward the shoreline. Eight of the witnesses said that
they heard a "pop" or "backfire," along with
a reduction in the engine noise level just before the airplane
descended into the water.
PILOT INFORMATION
The pilot's logbook was not recovered. During the investigation,
the pilot's FAA airman and medical records were obtained from
the Airman and Medical Records Certification Branch, FAA, in Oklahoma
City, Oklahoma. On his most recent medical application of record,
dated June 13, 1996, he reported a total flight time of 2,750
hours. He held a private pilot certificate, with airplane ratings
for single and multiengine land, single-engine sea and gliders.
He also held an instrument airplane rating and a Lear Jet type
rating.
Another Long EZ pilot (hereinafter referred to as the "checkout"
pilot), gave the pilot about 1/2 hour of ground and flight checkout
in the accident airplane in Santa Maria, California on the day
before the accident, before the pilot's departure for Monterey.
He said that they performed two touch-and-go landings and some
slow flight maneuvers, and that they discussed the aircraft systems,
including the fuel selector location. He said that he had made
arrangements with the pilot to relocate the fuel selector handle
while the pilot, a musical performer, was away on tour. He also
said that a pillow was placed on the back of the pilot's seat
to assist him in reaching the rudder pedals.
The checkout pilot stated that about a month before the accident,
he had flown in the front seat with the pilot on a demonstration
flight in the accident airplane. He said the pilot had also flown
in the backseat on two other Long EZ demonstration flights.
A certified true copy of the pilot's FAA medical record files
were obtained and reviewed by Safety Board investigators. According
to the pilot's FAA medical records, the physician who examined
the pilot on June 13, 1996, issued a third-class medical certificate
to the pilot at the conclusion of the examination. His FAA medical
records further showed that on November 6, 1996, the FAA Civil
Aeromedical Certification Division sent the pilot a letter by
certified mail, return receipt requested, acknowledging receipt
of his June 13, 1996, medical application and stating, in part:
We had previously received an interim report from H. C. Whitcomb,
Jr., M.D., pertinent to your alcohol problem. Dr. Whitcomb reported
that "in general averages two to four drinks of either wine
or beer/week when he's traveling." He further stated that
there has been no abuse, (see footnote 1) ...in our letter of
October 18, 1995, we specified that your "continued airman
medical certification remains contingent upon your total abstinence
for use of alcohol."
The letter informs the pilot that based on the above information,
he did not meet the medical standards prescribed in Part 67 of
the Federal Aviation Regulations, and a determination was made
that he was not qualified for any class of medical certificate
at that time. The letter further states: "If you do not wish
to voluntarily return your certificate, your file may be sent
to our regional office for appropriate action." According
to U. S. Postal Service markings on the envelope, the letter was
returned unclaimed to the FAA on December 2, 1996.
Examination of the FAA medical file disclosed that following the
return of the unclaimed November 6, 1996, letter there was no
followup action by the FAA until March 25, 1997, when the agency
sent the pilot a second letter by certified mail, return request
requested, again notifying him that he was medically disqualified.
The return receipt for the certified letter was examined by Safety
Board investigators; however, the signature of the person who
had signed for the mail was illegible.
AIRCRAFT INFORMATION
The accident airplane was an experimental amateur built canard
(1) type aircraft. The data plate indicated a manufacture date
of June 1987. The airplane was designed by Rutan Aircraft Factory
and was built from the Rutan plans by Adrian D. Davis, Jr. Review
of FAA Aircraft Registry records for the airplane revealed that
the original builder applied for an airworthiness certificate
in the amateur-built, experimental category on May 5, 1987. The
airworthiness certificate was issued by an FAA Airworthiness Inspector
from the Houston, Texas, Flight Standards District Office on June
12, 1987. On the application, the inspector checked the box stating
"I have found the aircraft described meets the requirements
for the certificate requested." A letter of operating limitations
was also issued on that date and included the statement: "This
aircraft shall contain the placards, listings and instrument markings
required by FAR 91.3 (Subsequently redesignated 14 CFR 91.9).
The airplane was equipped with an electric force bias trim system
for both the pitch and roll axis, and an electrically actuated
speed brake that deploys from the fuselage belly. The switches
for the electric trim and the speed brake were located on the
side stick controller. The airplane was equipped with a single
axis roll autopilot, but the autopilot was not recovered.
According to the checkout pilot, and confirmed by the seller,
the canard had the Ronz No. 1145ms airfoil.
According to the operator's manual, the Long EZ was designed either
for a rear mounted Continental O-200 (100 horsepower (hp)) or
a Lycoming O-235 (115 hp) engine. The engine installed on the
accident airplane was a Lycoming O-320-E3D, producing 150 hp and
consumes 8.5 to 10 gallons of fuel per hour depending on the power
setting. This engine installation also required the installation
of 50 pounds of ballast in the nose. An electrical starter was
also installed on the engine.
The airplane's designer provided a written statement to the Safety
Board in response to an inquiry regarding the compatibility of
the airframe with the Lycoming O-320 engine. He stated that "the
only engines approved by the factory for installation" are
the Continental models O-200 or O-240, or the Lycoming O-235.
The designer reported that he is aware that some Long EZ's have
been modified with engines of up to 200 horsepower and operate
at weights 50 percent above the prototype limit, and that "this
level of experience with growth versions does indicate that there
are substantial margins in the design. According to the pilot
who sold the airplane to the accident pilot and the checkout pilot,
disclosed that no ballast was installed in the nose. However,
two batteries, totaling 40.8 pounds, were relocated in the nose
section, one directly in front of the foremost bulkhead and the
other just behind it.
FAA records indicate that the seller who sold the airplane to
the accident pilot purchased the airplane from the builder on
March 5, 1994. On April 13, 1996, the seller changed the registration
number from N5LE to N228VS. According to the seller, the airplane
was sold to the accident pilot on September 27, 1997. The airplane
was then (by the checkout pilot) flown from Santa Ynez to Santa
Maria, California, to be repainted in connection with the sale
to the pilot. During the repainting of the aircraft, the registration
number of was changed by the pilot to N555JD.
At Santa Maria, the airplane was sanded, primed, and painted.
Telephone interviews with personnel at the paint shop revealed
that the old paint was not stripped off. No control surfaces were
removed at any time. The only items removed during the painting
were the two wing-mounted cargo pods, which were painted in a
multicolored scheme and reinstalled. As applied, the paint weighed
about 4 pounds per 100 square foot, according to paint shop personnel.
During the investigation, copies of a empty airplane weight and
balance document, dated May 18, 1996, were located at Craftsmans
Corner, Santa Paula, California. It listed an airplane empty weight
of 1,061 pounds and center of gravity (CG) at 110.0 inches. In
an interview, the manager of Scaled Composites, Inc., (Rutan Aircraft)
estimated that, based on the total wetted area of the airplane,
the paint applied at Santa Maria would have added 30 pounds to
the empty weight for a total of 1,091 pounds with a CG at 110.0
inches.
Based the weight and balance document and estimates of the airplane's
probable fuel load at the accident flight's departure from Monterey,
gross weight and CG conditions were calculated and are appended
to this report. Those calculations show that at the beginning
of the accident flight, the airplane would have had a gross weight
of approximately 1,310 pounds, with a CG at 103.65 inches. At
the time of the accident, the airplane would have had a gross
weight of approximately 1,280 pounds, with a CG at 103.63 inches.
According to Scaled Composites Inc., the design gross weight limit
is 1,425 pounds and the CG range is from the forward limit of
98 inches to the rear limit of 103 inches.
In a telephone interview on June 15, 1998, an engineering representative
from Scaled Composites, Inc., reported that the airplane was designed
with a published aft limit of 104 inches, and the prototype was
extensively tested and flown at this limit. Subsequently, in the
interests of conservative margins, the designer changed the published
limit to 103 inches. According to the designer during flight tests,
the prototype was flown at 106 inches and flew all test points
satisfactorily, and no adverse handling characteristics were noted.
The representative from Scaled Composites, Inc., also reported
that the company flew the same profile as that believed to have
been flown during the accident flight (start, taxi, run-up, takeoff,
three touch-and-goes, and a pattern departure) in a Lycoming O-320-equipped
Long-EZ and measured the fuel consumed at 3.6 gallons. After running
one tank dry, a time interval of 6 to 8 seconds was measured between
changing the fuel selector and the resuming of engine power. The
representative stated that although the fuel tanks of the airplane
were extensively damaged, during the wreckage reconstruction he
observed that the fuel tanks were built to plan specifications.
The representative of Scaled Composites, Inc. said the system
does not appear to have an unusable quantity. Two sumps, each
having about a quart capacity, are located in the tanks. The tank
is designed so that the fuel will feed into the sumps in all flight
attitudes. The representative said the only known condition that
would tend to favor an unporting is in a prolonged descent with
just a few gallons of fuel in the tank.
According to the designer of the airplane and the drawings issued
to the builder, the fuel selector is to be located just aft of
the nose wheel position window between the pilot's legs. The accident
airplane's fuel selector handle was positioned by the builder
on the bulkhead behind the pilot's left shoulder. The selector
valve was installed inside the engine firewall 45 inches aft of
the selector handle. The handle and valve were joined by steel
and aluminum tubing, connected by a universal joint.
According to the designer and the seller, this type of airplane
has two 26-gallon fuel tanks in the wing roots that contain usable
fuel. The fuel quantity is determined by viewing non-linear sight
leave gauges located in the rear cockpit at the wing roots. The
sight gauges show an amount of actual fuel supporting a red float.
Postaccident examination of the airplane disclosed that the sight
gauges were not marked or calibrated for quantity.
The maintenance technician who helped the pilot move the airplane
out of the hangar before the accident flight mentioned that the
fuel sight gauges were only visible to the rear cockpit occupant.
The pilot then asked the technician about the quantity of fuel
shown. The technician told the pilot that he had "less than
half in the right tank and less than a quarter in the left tank."
The technician said that he estimated the fuel quantity based
on the assumption that the gauge presentation was linear. The
technician provided a shop inspection mirror to the pilot so that
he could look over his shoulder at the fuel sight gauges. The
mirror was recovered in the wreckage.
According to other pilots who were familiar with the airplane
and/or had flown it, to change the fuel selector a pilot had to:
1) Remove his hand from the right side control stick if he was
hand flying the aircraft; 2) Release the shoulder harness; 3)
Turn his upper body 90 degrees to the left to reach the handle;
and 4) Turn the handle to another position. Two pilots shared
their experiences of having inadvertently run a fuel tank dry
with nearly catastrophic consequences because of the selector
and sight gauge locations.
The fuel selector handle location was discussed with the seller
and other pilots who had flown the accident airplane. The seller
reported that he had asked the builder why he had located it behind
the pilot's left shoulder. The builder responded that he did not
want fuel in the cockpit area. The seller said that when he changed
tanks inflight he would engage the autopilot, allowing his right
hand to reach behind his left shoulder to the selector handle.
The seller said that at the time of the accident, the handle was
"firm to turn with good detents." He also said that
the checkout pilot had removed the selector valve for cleaning
and lubricating some time ago. The checkout pilot said that the
seller attempted to work on the valve in early 1996, but that
he (the checkout pilot) ended up finishing the repair in April
1996. He also said that he had removed the two rivets that were
drilled through the brass valve shaft and the he had replaced
one of the two torque tubes.
The checkout pilot was asked about the selector. He said that
he had simulated changing tanks using the selector on one occasion
on the ground and that he was not pleased with the location. Because
of the difficulties of using the selector, he said that he had
never used the selector in flight.
Postaccident wreckage examination by Safety Board investigators
revealed that the selector handle was not placarded or marked
for any operating position. According to the checkout pilot, the
handle in the right position was for the left tank, the handle
in the down position was for the right tank, and the off position
was up.
When investigators attempted to switch fuel tanks in a similar
Long EZ, each time while an investigator turned his body the 90
degrees required to reach the valve, his natural tendency was
to extend his right foot against the right rudder pedal to support
his body as he turned in the seat.
Concerning the yaw flight controls, the representative from Scaled
Composite, Inc. reported that the rudders move and serve as vertical
spoilers. Pressing on the right rudder peddle moves only the right
rudder in an outboard direction, which produces increased drag
and a subsequent yawing moment. He stated that the rudders are
very effective because of the long moment arm. With a center of
effort (increased drag) above the longitudinal CG, activation
of a rudder will produce a pitch-up moment along with the yaw.
The airplane also has a very strong spiral mode. He also reported
that the lateral roll control with the side stick controller is
very sensitive and that a 1/8 inch movement will cause a roll
initiation.
The airplane's logbooks were not recovered. According to the seller
of the airplane, the airframe and engine had accumulated about
850 total flight hours. He reported that the last FAA-required,
12-month condition inspection had taken place on September 20,
1997.
The checkout pilot who flew the airplane from Santa Ynez to Santa
Maria for repainting estimated that before his departure 5 gallons
of fuel was on board with 2 gallons on one side and 3 gallons
in the other. He stated that he added 10 gallons of fuel to each
tank. The checkout pilot said that he did not update the Fuelwatch
(2) fuel monitoring instrument after refueling because he was
not familiar with the procedure. The flight to Santa Maria lasted
10 minutes it is estimated to have consumed 2 gallons of fuel.
During the pilot's 30-minute checkout at Santa Maria, the checkout
pilot estimated that 4 gallons of fuel were consumed.
The checkout pilot stated that the pilot flew the airplane from
Santa Maria to Monterey, and that he had departed with about 19
gallons of fuel onboard. There were 12.5 gallons of fuel in the
right tank and 6.5 gallons in the left tank. He noted that the
selector was located on the right tank before to the pilot's departure
from Santa Maria.
The Safety Board and the parties to the investigation estimated
that the amount of fuel required to fly to Monterey from Santa
Maria ranged from 6.4 to 9.1 gallons, depending on the power settings
used. Estimates for fuel used during the checkout flight at Santa
Maria ranged from 2.5 to 3.6 gallons. The accident flight was
estimated to have consumed 3.0 to 4.3 gallons, for a combined
total consumption of 11.9 to 17.0 gallons of fuel. Fuel records
disclosed that the airplane was not refueled at Monterey Airport.
WRECKAGE AND IMPACT INFORMATION
The wreckage was located the Pacific Ocean in 30-foot water within
about 150 yards of the rocky shoreline near Pacific Grove, California.
An underwater video taken by a diver from the National Oceanic
and Atmospheric Administration, Monterey Bay National Marine Sanctuary,
revealed broken rock structures where the airplane wreckage was
located on the ocean floor. The broken sections of rock were free
of normal underwater growth.
The recovery was made by members of the Pacific Grove Ocean Rescue
Team and members of the Sheriff's Dive Team. All major structural
components of the airframe were found in a fragmented state on
the ocean floor near the engine. Most of the control system rods
and rod ends were recovered. The landing gear assembly was separated
from the fuselage, and the right wheel and brake were separated
from the gear leg. The nose gear was found in the retracted position.
The engine was found separated from the airframe structure but
remained attached to its mounts. The mounts were crushed in a
forward direction. Two induction tubes were found broken from
the engine. The wooden composite-covered propeller hub was still
attached to the engine crankshaft flange. Both propeller blades
were severed about 18 inches outboard of the hub center. Fragmented
composite propeller blade coverings and blade wood were recovered
near the engine. Subsequent layout disclosed that the fragments
comprised the leading edges of both blades.
The engine was examined externally and internally. Gear and valve
train continuity was established by rotation. Cylinder compression
was established. All cylinders were removed and examined. The
accessory housing was removed for examination of the oil pump
gears and crankshaft gear. The carburetor was removed and opened
for a visual examination. Fuel and water were found in the carburetor
bowl. The magnetos had been replaced with an electronic ignition
system. There were no discrepancies found during these examinations.
During the investigation, the wreckage was laid out with the recovered
components placed in their normal positions. All aircraft extremities
were accounted for in the examination. All recovered control system
push-pull tubes and associated bell cranks were examined, with
overload signatures evident and no unusual operating condition
noted. No battering or over-travel signatures were observed to
any control limit stop.
MEDICAL AND PATHOLOGICAL INFORMATION
On October 13, 1997, the Monterey County Medical Examiner performed
an autopsy on the pilot. According to the report, the cause of
death was multiple blunt force trauma. During the examination,
samples were obtained for toxicological analysis by the FAA's
Civil Aeromedical Institute in Oklahoma City, Oklahoma. Tests
were negative for all screened drugs and Ethanol.
TESTS AND RESEARCH INFORMATION
The fuel selector, linkage, universal joint, handle, and handle
bearing block were recovered. The brass selector stem/shaft was
found fractured between two opposing drilled rivet holes that
attach the hollow portion of the shaft to the torque tube/handle
linkage. The Safety Board's Materials Laboratory examined the
stem/shaft fracture. Although the stem/shaft was severely weakened
by the rivet addition, there was no evidence of pre-impact failure
on the stem. A copy of the laboratory report is attached.
The brass 3-port Imperial fuel selector valve assembly was examined
and found in an intermediate position, which was one-half open
between the engine feed line and the right tank fuel supply line.
The port to the left tank was also observed to be open about 2
to 4 percent to the engine feed line. The valve was found frozen
in place and could not be moved. The fuel valve was plumbed into
an engine test cell, with the fuel supply connected to the valve's
right tank fuel port. At that point, the left tank port was open
to the atmosphere and was subsequently capped. An exemplar Lycoming
O-320 engine was installed in the test cell, started and run to
maximum power. The one-half-open right port position had negligible
effect on the engine power output; however, when the cap was removed
from the left port (simulating the effect of an empty left tank)
the fuel pressure dropped to less than one-half, and within a
few seconds the engine quit because of the fuel/air mixture resulted
in a vapor state.
The steel and aluminum rods connecting the handle to the fuel
selector valve were found bent. The rods were straightened to
determine the handle position relative to the valve position.
Extensive metallurgical and installation examinations were performed
at the Safety Board Materials Laboratory and with exemplar aircraft
in the field. Copies of the laboratory reports are attached.
The Safety Board examined the recovered wreckage for evidence
of a possible bird strike. There were no leading edge canard or
wing sections intact. The canopy was destroyed, and only fragments
of the Plexiglas were recovered. Bird feathers were found commingled
in the recovered wreckage. The curator of the local Museum of
Natural History was asked to view the feathers during the wreckage
examination. A seat cushion determined to be from the accident
airplane was found torn open. According to the cushion material
tag, it was filled with goose feathers; however, the curator also
found duck feathers in the cushion. The cushion feathers matched
the ones found commingled with the wreckage.
ADDITIONAL INFORMATION
The wreckage was released to the insurance adjuster representing
the pilot on June 10, 1998. When it was last viewed by investigators
the wreckage was located at Monterey, California.
1 A type of airplane in which the pitch controls that are normally
mounted on the empennage of the airplane are mounted ahead of
the main lifting plane. An airplane on which the pitch controls
are mounted forward of the wing rather than behind the wing.
2 A fuel management system that provides a fuel burn rate and
fuel remaining.
FOOTNOTE 1:
1 The letter from Dr. Whitcomn dated March 22, 1996, was also
in the pilot's medical file it stated: "In general, he has
done remarkably well. For the last three weeks, he has been on
a fast and has had absolutely no alcohol, but in general averages
two to four drinks of either wine or beer/week when he's traveling.
There has been no abuse. The patient seems very happy and balanced
at this stage of his life."
Return to synopsis
Boeing 747 Fuselage Rupture at Aft midspan
Latch of Forward Cargo Door
Boeing 747 Electrically Caused Inadvertent
Cargo Door Openings