NTSBDEBRIEFER
H O\N
BY PETER KATZ
Tight Is Tight ?
Even if you're really thorough, you can't always tell during preflight whether something is coming apart
contact with the facility and advised the
Beech 95-B55
controller that the flight was climbInJanuary, the NTSB finished its invesing through 2,500 feet. The flight was
tigation of an accident that occurred on
radar identified and instructed to climb
November 24, 2008. It was late mornto 7,000 feet continuing toward the
ing when a twin-engine Beech 95-B55
destination airport.
crashed in a wooded area behind a house
About 21 minutes before
in Whites Creek, Tenn. The
the accident, the pilot was
airplane had been on an IFR
GO TO
instructed by Memphis Cenflight plan, and on the ground,
plin 81 nd pi IOlilig.co II/
ter to descend and maintain
a witness said there were low
pilol-Ialk.hlml
4,000 feet. A few minutes
clouds and drizzle at the time
Access previous editions
later, the flight was handed
of the accident. The airplane
of NTSB Debriefer & other
off to Nashville Approach.
was on a business flight from
regu lar columns
The controller told the pilot
Hot Springs, Ark. , to Nashville
that ATIS Sierra was curInternational Airport (BNA) ,
rent,
and
to
expect vectors for an ILS
Nashville, Tenn. The commercial pilot
approach to runway 20R. About three
and both of his passengers were killed.
minutes later, at 10:36:24, the pilot was
Before takeoff, the pilot contacted the
instructed to fly a heading of 055 degrees
Memphis Air Route Traffic Control Cenfor sequencing. Radar showed that from
ter, and requested IFR clearance to the
10:37:21 to 10:42:21, the airplane flew
destination airport. The pilot was
approximately the heading given by the
instructed that the flight was cleared as
controller. Then, it turned left of course.
filed , to climb and maintain 5,000 feet,
At 10:42:58, the controller alerted the
expect 7,000 feet 10 minutes after deparpilot to another airplane and the pilot
ture, given a transponder code of 5524,
radioed, "Yeah, well, I'm all screwed up
and advised of the clearance void time.
up here, so stick with me. "
The pilot correctly read back the clearThe controller asked the pilot if he
ance, and at 9:11 a.m. , he established
needed help. The pilot asked how far he
was from the localizer. The controller
told him he was 12 miles from the localizer, and asked the pilot to make sure
he wasn't confusing the John Tune Airport ILS frequency (110.3 MHz) with
the BNA runway 20R ILS frequency of
111.3 MHz. The pilot replied with words
to the effect that he had 111.3 selected.
The controller told the pilot to fly his
present heading, and to expect a base
and final turn to the localizer. The pilot
didn't respond. The controller again
advised the pilot to expect a base tum
in five miles, and a tum south onto the
localizer. The pilot radioed, "Gotcha. "
At 10:44:24, the controller called the pilot
and he replied, "I've got you, but I'm
FORCED LANDING. A Cessna 172, like the one above, had to make a forced landing after a loss of
having trouble hold .. .." There was backpower due to oil starvation. Maintenance had failed to tighten bolts for a new vacuum pump.
ok through a Piper Cherokee service manual from the 1970s, and
ou'll note that the manufacturer
gets pretty specific about certain things,
such as requiring spark plugs to be
torqued into the cylinders at between
360 and 420 inch-pounds, and fuel
primer jets to be tightened at 60 inchpounds. Forces necessary to ensure
holding power are frequently specified
by manufacturers, but when they're not,
mechanics are required to exercise sound
judgment based on skill and experience. As pilots, this is just one more
area in which we have to trust that our
mechanics aren't going to let us down.
The chances of a pilot being able to
detect an improperly torqued part even
in what seems to be a thorough preflight inspection are pretty slim. If
installed properly, the spark plugs, fuel
primer jets and numerous other parts
on which your life depends will stay
put despite the vibration, heat, cold and
stresses that are part of everyday flying. When things aren't secured as
they're supposed to be, it sometimes
becomes the NTSB's business.
W
62 PLANE & PILOT planeandpilotmag.com
ground noise followed by grunting sounds.
The controller asked the pilot if he needed
help, and he responded, "I got it into a
spin and I can't stop it." Heavy breathing and more grunting sounds followed.
At 10:44:54, the controller advised the
pilot to climb immediately to 3,000 feet.
The pilot responded with, "Got no climb."
At 10:45:09, the controller again told the
pilot to climb immediately. There was
no further response from the pilot. The
controller then broadcast in the blind
that the airplane was six miles north of
John Tune Airport, and that rescue vehicles had been dispatched.
Radar data indicated that the ground
speed of the airplane dropped to only
51 knots when it was less than onehalf mile from the accident site, a sure
sign that the pilot was having difficulty
controlling airspeed.
A witness saw the airplane flying in
a southwesterly direction. The witness
told investigators the airplane began spinning in a counterclockwise direction,
and that it was flat while spinning. The
witness estimated the airplane spun four
times before it went out of sight. Each
rotation took approximately one second.
He called 911, and ran to the scene.
When he arrived there, he noticed a fire
at the front of the airplane that spread
out. He estimated the fire department
arrived in five minutes.
The pilot, age 67, held a commercial
pilot certificate with ratings for airplane
single-engine land, airplane multi-engine
land and instrument airplane. His logbook wasn't located, but investigators
estimated from other records that he had
about 2,000 total flight hours.
Investigators determined that the left
engine wasn't operating when the airplane crashed. About eight months before
the accident, both propellers and propeller governors were removed for overhaul, and both engines were removed
and replaced with remanufactured engines.
Logbooks revealed that about six months
before the accident, the mechanic who
installed the engines changed the engine
oil and cleaned the oil screens of both
engines. The entry for the left engine
indicated, " ... Ground Run. No Leaks
Noted At This Time." There was no further entry in the left-engine logbook following the oil change indicating any
further maintenance was performed.
Examination of the left propeller
revealed that it had not been feathered
follOwing the loss of engine power. Investigators found the fuel-supply line from
the firewall to the left engine's fuel pump
disconnected from the fuel-pump inlet
fitting. They concluded that the discon-
nect wasn't a result of impact damage.
During operational testing of the left
engine, the B-nut at the engine-driven
fuel-pump-supply inlet fitting was made
only finger tight, not torqued to the value
specified by the airframe manufacturer.
Approximately two minutes into the
engine run, the fuel hose separated from
the inlet fitting. During the loosening
process, fuel leakage was noted, but the
engine continued to operate at the rpm
setting investigators selected until the
hose completely separated. Examination
of the fitting by the Safety Boards' Materials Laboratory in Washington, D.C. ,
confirmed that the fitting had been loose
for some time before finally separating
during the accident flight and causing
the total loss of left-engine power.
The NTSB determined that the probable cause of this accident was the pilot
failing to feather the left propeller and
secure the left engine follOWing the
power loss, and his subsequent failure
to maintain airspeed and lateral and
directional control of the airplane. Con-
planeandpilolmag.com JUNE 2011 63
NTSB
PHOENIXMOTORGLIDER
(from page 39)
tributing to the accident was the failure
of maintenance personnel to properly
tighten the fuel-supply hose at the enginedriven fuel pump.
Cessna 172M
We Asked YOU!
. .... ...... ... .
. .
... .... ........ ... ... . .. .....
Have you ever flown a motorglider?
14%
• No, but I would like to learn
6%
• No, and I have no interest
o Yes, I took a lesson once
o Yes, I am working on my rating
• Yes, I have a glider rating
Cowling wraps elegantly around the
beautiful engine installation that Rotax
guru Dean Vogel praised ... and he's seen
a lot of them. Even the gear legs flush
up with the bottom of the fuselage, and
as Lee says, "The legs themselves are
clean and strong ." Nothing seems to
have been overlooked in the quest for
minimizing drag.
Ouest For Air
Lee graced me with two separate flights
totaling more than two hours. The shortwing (36-inch-span) version felt very
much like a top-line LSA cruiser. In the
afternoon, he plugged on the 15-meter
extensions, and we spent an hour thermaling in the weak lift. Turns, climbs
and descents for both versions were
smooth and solid. The controls are well
placed and feel just right. It's just a wonderful airplane to fly in either mode.
We pulled stalls, straight ahead in
climb and descent, and in high-bank
64 PLANE & PILOT planeandpilotmag.com
turns typical of thermaling speeds. Stall
behavior? Nominal, with no nasty habits.
Phoenix really holds onto a tight bank,
great for rising up in tight-cored thermals. The onset-stall-warning buffet is
easy to distinguish, and recovery is typical of any quality nonsoaring LSA-just
feed in some forward pitch, and you're
flying again.
Roll rates are surprisingly brisk, even
for the long wing : a bit over three seconds, 45 degrees to 45 degrees. And the
shorter wing? Downright snappy at two
seconds! Thank the full-span flaperons
(both short and long wings).
If the adventure of sailing the living
energy between earth and sky using both
gas and sun-fueled power is calling you,
don't even hesitate: Contact Jim Lee and
treat yourself to this dream-come-true
work of aerodynamic art.
P&:P'
planeandpilotmag.com
Learn more about the airplanes featured in Plane &
Pilot and Pilot Journal at planeandpilotmag.conVain:raft.html.
On June 30, 2008, a Cessna 172M had
to make a forced landing near Oakland,
Calif. The commercial pilot and his passenger received minor injuries. Weather
was good for the traffic observation flight.
The pilot said that when the engine began
surging and running rough, he adjusted
the mixture to full-rich position, which
seemed to help. Seconds later, the pilot
noticed that the engine oil-temperature
gauge was rising. He elected to divert
toward the Oakland International Airport. Before they could reach the airport,
the engine lost power. He headed for an
open lot. During the landing roll, the airplane hit a large mound of dirt.
The bottom of the airplane was coated
with oil from the engine to the tail. The
engine dipstick indicated no oil was in
the sump. All four nuts that secured the
vacuum pump to the mounting pad were
found loose. Oil was observed on the
rear accessory housing below the vacuum pump and between the left and
right magnetos. When compressed air
was put into the oil cooler inlet line,
bubbling oil came out of the vacuumpump mounting pad.
Investigators found that the vacuum
pump was replaced after the flight that
took place before the accident flight. The
FAA inspector who responded to the
accident site interviewed the mechanic
who put in the vacuum pump. The
mechanic said he tightened all the nuts
holding the vacuum pump except for
the bottom left, which he couldn't reach.
According to the FAA, the mechanic said
he used a screwdriver and hammer to
tighten that nut.
The NTSB determined that the probable cause of this accident was a loss of
engine power due to oil starvation. The
oil-starvation event was due to the failure of maintenance personnel to tighten
the mounting bolts for the newly installed
vacuum pump.
P&:P
Peter Katz is editor ane! pllblisher o{NTSB
Reporter, an independell t monthly update
Oil aircraft (l(cidcni.
invcstigatioll s and oOn:r
conc/:11l ing tin: National Transpor(Cltioll Safety Board. To subscribe, write to:
NTSB Reportf/", Subscription Dept., P.O.
Box 831 , Wllite PIClins, NY 10602-0831.
lIews