summer approaches, temperatures increase and density altitude becomes
an important consideration for pilots. High density altitude can affect
aircraft in several ways. Wing or rotor lift is decreased. Engine power
is reduced. Propeller, rotor, and jet engine thrust are decreased. Degraded
aircraft performance results in increased takeoff distance, reduced
rate of climb, increased true airspeed on approach and landing, and
increased landing roll distance.
calculation of performance data and strict adherence to Pilot's Operating
Handbook (POH) procedures are critical for high density altitude operations.
instructor and student used the POH to calculate the rotation speed
but neglected to follow the procedure for leaning the fuel mixture.
They put their C172 into a spot where there was not enough speed to
takeoff and not enough runway left to abort.
full tanks and increasing density altitude, the engine was unable
to produce the needed power to achieve the rotation speed of 48 knots.
After passing the intersection of Runway 13/31 we were at 42 knots.
At this point we decided to rotate because there was not enough runway
left to abort the takeoff.... Unfortunately, after rotation, the stall
warning horn sounded at about 10 feet. We did not have enough distance
to climb and clear the obstacles at the departure end of the runway.
We decided to cut the power and land.... At this point we believed
that there was some runway and hard grass surface to stop the plane.
Unfortunately, the brakes did not catch the wet grass and we slid
into the plowed field 200 feet south of the runway....
my opinion, if we had tried to keep it in the air the outcome could
have been much worse. However, there were some errors in our judgement.
The density altitude was significantly higher than it had been in
the last several months. Keeping the high density altitude in mind,
apparently one thing that we could have done to produce more power
[would have been to] lean the mixture for takeoff....
general, when the density altitude exceeds 5,000 feet, normally aspirated
engines should be leaned for optimum performance. Follow the POH procedures
for specific aircraft and engines.
Heavy, Fast, and Fortunate
an aircraft is operating at the edge of its performance at a high density
altitude there is no room for error- even in the cool of the night.
was landing at night.... I came in too fast. About 3/4 of the way
down the 4,700 foot runway, I decided to go around. Density altitude
was about 8,000 feet. The gross weight was 2,260 lbs. and max weight
is 2,300 lbs. for the C172. When I retracted the flaps for the go-around
(the flap switch is not notched), the flaps went to 0 degrees and
I lost lift and altitude. I saw that I was not going to clear the
power lines about 1,500 feet away, so I landed the plane on a grass
field past the end of the runway.... It was my second landing at this
field and only my third landing at high altitude....
Joins Wheat Watchers
Let's try that again," is not something you want to hear from your
surgeon. And, as a passenger of a light aircraft departing a high altitude
airport, it is not something you want to hear from the pilot after he
takes off and settles into a wheat field.
took off, climbed to 5,800 feet, retracted the flaps, and descended
into a wheat field. I pushed the plane onto a road. The passengers
departed the airplane and went back to [the airport]. I took off from
the road, proceeded back to the airport, and picked up the passengers.
[I] took off again and proceeded home.... The density altitude was
approximately 8,700 feet. The aircraft was within 200 lbs. of max
gross weight. A maintenance checkout found no problems with the engine.
a powerful World War II training aircraft can have a hard time when
a soft runway is combined with a high density altitude.
was at an altitude of [over 4,000] feet with temperatures in the 90's.
Density altitude was estimated at 8,000 feet. [I] selected the grass
runway which is approximately 4,700 feet long. The aircraft did not
maintain flying attitude after rotation and proceeded off the runway
into a plowed field. I should have determined the effect of using
a grass runway on the takeoff performance....
Gardiner of the FAA's Seattle Flight Standards District Office has published
an excellent review based upon the density altitude seminars given by
National Transportation Safety Board (NTSB) Accident Investigator Kurt
Anderson. The article was printed in the May/June FAA Aviation News
which is available at: http://www.faa.gov/AVR/afs/news/
following, although not mandatory, is certainly recommended for aircraft
operating VFR in or near congested airspace. A request for flight following
alerts ATC to the presence of an aircraft which may not be apparent
on radar and can enable traffic advisories (controller workload permitting)
to be given to the pilot. If a transponder is required for the airspace
in question, then it is incumbent upon the pilot to ensure that the
unit is operational and activated. The airborne TCAS (Traffic Alert
and Collision Avoidance System) also relies upon transponder signals
to identify traffic conflicts. Use of flight following and/or activation
of a transponder by the Cessna in this incident could have prevented
a Near Mid-Air Collision (NMAC).
Carrier] X departed on a Standard Instrument Departure. About six
miles from takeoff, I vectored him to 090 degrees to go around [Air
Carrier] Y at 5,500 feet. I issued [Air Carrier] X traffic at two
o'clock, five miles, 5,500 feet northbound. The pilot looked for the
traffic, but saw a Cessna instead and had to dive to avoid a collision.
No targets were observed between the two air carriers on radar at
the time I issued the traffic. Upon replay of the radar data, a diamond
symbol, used for primary targets on the ARTS (Automated Radar Terminal
System) display, was observed to be first displayed five miles south
of the NMAC point. No slash representing a primary target skin paint
return or a transponder return was displayed. There was no history
of this target being displayed prior to this point.... The most important
factor preventing me from viewing the Cessna target was the fact that
the diamond symbol was concurrent with the data blocks and targets
of two other aircraft circling in the area....
no time did the target display a transponder code.
better radar return on the Cessna certainly would have helped, but
the heavy concentration of traffic and several other aircraft in
the immediate area cluttered the radar presentation so much that
just seeing all the data blocks, let alone stray traffic, became
difficult. Even more important, as a controller and pilot, I feel
that flying the route and altitude the Cessna took over a major
air traffic area was not consistent with good planning and procedures
unless the pilot had used Flight Following from ATC.
know that many pilots think ATC can see them, but if their transponder
is not working properly, we won't see them and they won't know it.
Perhaps this could be addressed at the FAA's pilot briefings or
in biennial flight reviews.
Good-bye to Trouble
the event that inebriated passengers manage to get through the boarding
process, sharp cabin crews can prevent in-flight disruptions by removing
them before takeoff.
was working as Flight Attendant #1 when Flight Attendant #4 informed
me that there were 11 first class passengers instead of the 10 listed
on my final paperwork. I called out names on my list and matched them
with all passengers except for one in seat 1X. She told me her name,
which was also the woman's name in seat 1Y. So, I asked to see their
boarding passes and 1Y handed me the one for her connecting flight...
She said she didn't have the one for this flight. I asked for her
identification and verified that she was who she claimed to be. I
then asked the person in 1X for her identification and she said she
didn't have it. I told her she did or she wouldn't be on the plane.
I called the Captain and he said she had better show some identification
now or we were going to return to the gate. She got out of her seat
and stood directly in front of me and said quietly, "Oh, I'll
show you something." She then very slowly lifted the flap of
her purse and pulled out her identification. She was not who she claimed
to be. I asked her if she had been drinking and she said "Well
yeah." I had her sit back down because she was swaying and talking
very slowly. I called the Captain again to inform him of the passenger
being drunk and lying about who she was. He said the agents were meeting
the plane back at the gate.... As the inebriated passenger exited
the airplane she turned to me and said, "What a safe airline
you run." I said, "We try to keep it as safe as possible.
the Maintenance Desk
from the number of reports submitted to ASRS, the problem of missing
or improperly secured engine oil caps is still a concern. Let's get
the word out and put a cap on this problem.
removing and replacing the oil filters I am required to have another
mechanic run both engines to perform a leak check on the filter assemblies.
After performing the leak check, the left engine required servicing.
At this time I noticed a ramp employee waiting for access to service
the lavatories. I serviced the oil to full and then moved the lift
truck, closed the cowling, and moved to the next engine. After completing
the work on the right engine and noticing that the ramp employee was
finished servicing the lavatories, I returned to latch the cowling
closed. I left the oil cap removed.
oil was discovered on the engine cowling of the #2 engine. Upon further
inspection it was found that the oil tank cap was unsecured. The engine
was serviced with six quarts of oil and continued in service. I had
serviced the engine oil the previous night and may have left the oil
tank cap for the #2 engine unsecured, causing the loss of oil. I have
a good system for ensuring that the oil tank caps are secure, but
it is possible that I may have erred on this occasion.... It was night,
with good weather conditions and no distractions....