曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
RA and began a descent.] At 500 feet AGL we leveled off, the TCAS
II still saying to descend at maximum rate. With high terrain
approaching, we started a maximum rate climb. TCAS II showed a
Traffic Advisory (TA) without an altitude ahead of us, and an RA
[at] plus 200 feet behind us…Had we followed the TCAS directions
we would definitely have crashed. If the weather had been low IFR,
I feel we would have crashed following the TCAS II directions. At
one point we had TCAS II saying ‘Descend Maximum Rate,’ and
the GPWS (Ground Proximity Warning System) saying ‘Pull Up,
Pull Up.’ [The] ATC [Controller] said he showed no traffic conflict at
any time.” (ACN 201637)
Erroneous Mode C
Controllers obtain altitude information about traffic displayed on
their radar from the Mode C function of the aircraft’s radar transponder.
If Mode C provides erroneous altitude information, the
controller will see an incorrect altitude displayed on the scope.
Should a controller note a disparity between displayed and assigned
altitude, he/she will ask the flight to confirm its altitude, and may
request that the flight crew reset their transponder, use a different
transponder, or disable Mode C.
Like a controller, TCAS II uses Mode C information to determine
vertical separation on other traffic. Should Mode C even temporarily
provide erroneous altitude information, an erroneous Resolution
Advisory command to climb or descend may result. Unlike a controller,
TCAS II cannot query the flight crew to determine if the problem
lies with malfunctioning equipment. Note the following pilot report:
“Our flight [air carrier X]…was at flight level
260…We observed a TCAS II advisory [TA] of
traffic at 12 o’clock, 1,000 feet above at about 15
miles on an opposing heading. Shortly after, we
observed traffic on [the] TCAS II display descend
from 1,000 feet above to 500 feet above. TCAS II
commanded a descent of at least 2,000 feet per
minute to avoid traffic.
“We queried…[ATC about the] traffic. They told
us we had an air carrier jet (Y) 1,000 feet below
us on a converging heading.… At about the same
time we visually acquired air carrier (Y) about
500 to 1,000 feet below our altitude. [The]
Controller confirmed he was assigned flight level
250. We observed no traffic above, nor did the
Controller have any traffic above us. Our TCAS
II continued to command a descent and continued
to show…[a] traffic conflict 500 feet above us.
[The] Controller advised that air carrier (Y)’s
Mode C did momentarily show 26,500 feet and
then returned to flight level 250 on their scope. We
had altered course slightly to the right to offset
[the] conflict, but did not follow the TCAS II RA.
If we had followed the TCAS II RA we, in my
opinion, would have impacted the opposing
aircraft.”
(ACN 210599)
The First Officer of the other aircraft (air carrier Y)
writes:
“…[Center] called traffic at 12 o’clock about 12
miles at 26,000 feet. I…spotted traffic about 7 to 8
miles out. Then we heard the air carrier jet (X)
report a TCAS advisory saying the guy was
showing 500 feet above them. Our aircraft was
not TCAS II equipped. I continued to observe our
traffic as he passed over us and in a slight righthand
bank. He appeared closer than the standard
1,000 feet separation. ATC then told us our
Mode C showed 26,500 feet. The Captain and I
both verified 29.92 [QNE] and 25,000 feet on our
altimeters…we were at 25,000 with a faulty
Mode C (which pilots have no way of monitoring).
This could have been a potentially fatal
situation had it not been visual [and daylight]
conditions.” (ACN 210600)
6 Issue Number 4
TCAS II — Genie Out Of The Bottle?
TCAS II Distraction
Pilots frequently cite TCAS II related auditory and
workload interference with normal cockpit duties,
as is noted in the following report from an air
carrier First Officer.
“…we received two TCAS II-advisories, corresponding
to departures. The departures are
cleared to 10,000 feet, [and] arrivals…[at] 11,000
feet. The TCAS II reacted to the closure rate of the
departing aircraft and our inbound flight. [The]
RA was ignored as traffic was in sight. The real
problem is that the TCAS II alert caused such a
distraction in the cockpit that two or more radio
calls from Approach Control were missed.” (ACN
203411)
Non-Standard Use of TCAS II
Some pilots are using TCAS displays to maintain
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
ASRS Directline(58)
