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
Problems will arise if several of the
above factors affect you at once,
especially if the landing point is
sloping—this is where frequent
cross-checking of altimeters is
important. The illusions you might
get with sloping ground include:
Problem Illusion Risk
Downslope Too low High approach
Upslope Too high Low approach
Rain Closer Low approach
Narrow Too high Low approach
Wide Too low High approach & flare
Bright lts Too low High approach
The trick with landing is to get to the
point where you think the wheels are
going to touch the ground – then go
down another 30 feet.
Helicopter landing sites should be
checked out in daylight on the same
day as they are to be used at night.
Preflight checks should allow for
night flying—carry a torch, and 2
landing lights are preferred.
Permission to enter the rotor disc is
given by flashing landing lights.
Hovertaxi higher and slower than by
day, making no sideways or
backwards movements. Great care
should be exercised in pointing the
Schermuly flares to a safe place at all
times (which is admittedly a bit
difficult when they're fitted and the
fuelling truck pulls up right alongside
them). The flares should not be
armed at this stage, but at the
holding point immediately before
take-off and disarmed at the same
place after final approach. They
Flight Operations 377
should also be disarmed after
reaching cruising altitude.
The maximum useful height for
discharging a flare is around 1800
feet. Its burn time is 80 seconds,
during which time it will fall about
1500 feet. Therefore, having
established autorotation after an
engine failure at night, the first flare
should be discharged immediately, or
on passing through 1800 feet,
whichever is later. Don't bother
doing it before this, as they will be
useless. Due to the way the switches
work, and depending on the height
at which your engine stops, you may
not be able to set off more than one
flare before landing, but, if possible,
the second should be discharged
between 800-1000 feet agl.
In autorotations at night, use a
constant attitude approach, at
whatever speed you feel is
comfortable, which will keep the
beam from the landing light in the
same position on the ground,
otherwise it will shine up into the air
when you flare, from which position
it's no good to you at all.
Flying Big Aeroplanes
Planes driven by jet engines are very
slick, in that there is no automatic
drag effect from reducing power as
you would get when a propeller is
involved. As mentioned elsewhere,
it's like driving a powerful car in
permanent high gear.
The power range of jet engines is in
the top end of the RPM band. When
increasing power, you have to
remember to give the engine time to
spool up, so expect a little delay
between applying power and seeing
the result, which means you need
more anticipation. In addition,. if
you reduce power, then increase it
again, the engine will spin down to a
low RPM then wind all the way up
again. This is why, on approach, that
relatively high thrust is maintained
against all those lift-and-thereforedrag-
producing devices, so the
power is there when you need it.
Large aircraft are heavy and have
high inertia. Good landings in them
result from being set up properly on
the approach, which comes in turn
from proper planning, as mentioned
above – do not put yourself in the
way of having to make abrupt
control inputs on finals. For this
reason, high descent rates (and
speeds) should also be avoided. A
good ploy is to multiply 50% of
groundspeed by 10 for a suitable
feet-per-minute glideslope (100
kts=500 fpm).
Hold the glideslope down to the
flare, planning to touchdown at the
ILS reference point at 100 feet in.
You need to keep the power on to
prevent sink, and enough stabiliser
trim to keep the elevator effective.
When over the threshold, flare, cut
to idle, allow for drift and land firmly
if the runway is wet (drive it onto the
ground). When down, relax the back
pressure and allow the nosewheel to
touch the runway smoothly. You
should not need any more forward
movement than that - according to
the 757 Training Manual, large nose378
Canadian Professional Pilot Studies
down control column movements
before the nosewheel touches the
runway can mean pitch rates that
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
Canadian Professional Pilot Studies2(110)
