曝光臺 注意防騙 網(wǎng)曝天貓店富美金盛家居專營店坑蒙拐騙欺詐消費(fèi)者

officially makes a golf course one,
though you would be forgiven for
thinking otherwise. A rule of thumb
is 60% buildings and trees, but
specifics haven't been tested in court
yet, at least not in the UK.
There should be at least one
approach and departure lane
containing either no or only isolated
obstacles—a downwind component
Operational Stuff 93
is not acceptable. The lanes and
landing areas should be big enough
to ensure you can land, take off and
reach a safe height so you can touch
down into wind following an engine
failure, while avoiding obstacles by a
safe margin.
Try not to have marshland
underneath the lanes because, while
it may be soft, skids or wheels may
sink in during an emergency landing,
which is the last place you want
dynamic rollover. In other words,
the ground beneath the lanes must
be suitable for emergency landings
with respect to slope, softness,
frangible obstructions, etc. Water is
OK, provided the performance
group is suitable or you've got the
usual lifejackets, floats, etc.
The landing pad itself should be
level, drained, with a grass or solid
surface that does not blow up dust at
(you should be able to drive the
average car over it). Its diameter
should be at least twice the length of
the largest helicopter to use it,
including rotors, as you will need to
turn round your tail. Watch out for
anything that may snag the skids,
particularly on takeoff. Some people
like the touchdown area marked with
an H, but provided the grid
reference is accurate enough, it
shouldn't be too hard to find it.
On an oil rig, the helideck frequently
will be sloped away from the centre,
to help with drainage. The slope is
not severe, but if you land with your
nose up the hill, so to speak, you run
the risk of hitting the tail rotor
against the perimeter fences.
Landing “downhill” will artificially
raise the tailboom away from them.
Finally, a couple of points to watch
if you’re ever tempted to land across
or near railway lines, as you might if
they’re the only firm place around.
The first is that your skids more
often than not will complete an
electrical connection used for
signalling, and you may cause some
confusion in the local signal box.
The other is that trains do use the
track outside of published schedules,
so don’t be surprised to see a
humungous diesel bearing down on
you unexpectedly.
Landing On Deck
First of all, you have to find the ship!
Once they've got full steam ahead,
Captains are very reluctant to slow
down for anybody, so be prepared to
look for your target a fair bit away
from where you (or the owners)
think it should be. However, they
may turn into wind a little bit, if you
ask them nicely.
Aside from knowing where the deck
is, you will need a radio frequency to
talk on, either the customer's own or
a general marine channel. This is not
only so you can ask where the heck
they are, but so they can give you the
wind and how much the deck is
going up or down (that is, pitching
and heaving, for the technical).
Flying around vessels is much like
doing it round mountains or
buildings, especially the latter, which
are more slab-sided. The wind does
strange things round them all, so
have the normal escape route handy,
by approaching obliquely. There will
be turbulence in the lee (and
elsewhere), so approach to the
windward side, getting into the
hover before you position for
landing as the highest point of the
94 The Helicopter Pilot’s Handbook
swell is reached, not when the boat is
rising - use your peripheral vision to
keep an eye on the deck, and focus
on the horizon, as normal. Look out
for ground resonance, and a slippery
deck, which will likely be sloping as
well. Stabilisers will compensate for
deck movement, so turn them off
once you are safely down.
When leaving, align yourself with the
way the ship is going (even if there is
a crosswind), and avoid the
superstructures on your way out.
Fuel
Helicopters don't need aerodromes,
and minimum fuel figures reflect
this. However, they are calculated
for level aircraft. Odd attitudes, say
when slinging, may cause a fuel
boost pump to become uncovered
and give you a nasty surprise just
when you don’t want it. On a 206,
the unuseable fuel after a boost
pump failure can be up to 10 US
　
中國航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：The Helicopter Pilot’s Handbook(62)