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
accelerate-stop distance required is greater than the
mnway length so determined, the excess may be
provided as stopway, usually at each end of the runway.
In addition, a clearway of the same length as the
stopway must also be provided;
b) if a stopway is not to be provided, the mnway length is
the landing distance required, or if it is greater, the
accelerate-stop distance required, which cmesponds to
the lowest practical value of the decision speed. The
excess of the take-off distance required over the runway
length may be provided as clearway, usually at each end
of the runway.
2.9 In addition to the above consideration, the concept of
clearways in certain circumstances can be applied to a
situation where the take-off distance required for all engines
operating exceeds that required for the engine failure case.
2.10 The economy of a stopway can be entirely lost if, after
each usage, it must be regraded and compacted. Therefore, it
should be designed to withstand at least a certain number of
loadings of the aeroplane which the stopway is intended to serve
without inducing structural damage to the aeroplane.
3. Calculation of declared distances
3.1 The declared distances to be calculated for each
mnway direction comprise: the take-off run available (TORA),
take-off distance available (TODA), accelerate-stop distance
available (ASDA), and landing distance available (LDA).
ATT A-2
Attachment A Annex 14 - Aerodromes
3.2 Where a runway is not provided with a stopway or 4.2 Consideration of longitudinal and
clearway and the threshold is located at the extremity of the transverse slopes
runway, the four declared distances should normally be equal
to the length of the runway, as shown in Figure A-1 (A). When a runway is planned that will combine the extreme
values for the slopes and changes in slope pemitted under
3.3 Where a runway is provided with a clearway (CWY), , Chapter 3, 3.1.13 to 3.1.19, a study should be made to ensure
then the lX3DA will include the length of clearway, as shown that the resulting surface profile will not hamper the operation
in Figure A-1 (B). of aeroplanes.
3.4 Where a mnway is provided with a stopway (SWY),
then the ASDA will include the length of stopway, as shown
in Figure A- 1 (C).
3.5 Where a runway has a displaced threshold, then the
LDA will be reduced by the distance the threshold is displaced,
as shown in Figure A-1 (D). A displaced threshold
affects only the LDA for approaches made to that threshold;
all declared distances for operations in the reciprocal direction
are unaffected.
3.6 Figures A-1 (B) through A-1 (D) illuswe a runway
provided with a clearway or a stopway or having a displaced
threshold. Where more than one of these features exist, then
more than one of the declared distances will be modified -
but the modification will follow the same principle illustrated.
An example showing a situation where all these features exist
is shown in Figure A-1 (E).
3.7 A suggested format for providing information on
declared distances is given in Figure A-1 (F). If a runway direction
cannot be used for take-off or landing, or both, because
it is operationally forbidden, then this should be declared and
the words "not usable" or the abbreviation "NU" entered.
4. Slopes on a runway
4.1 Distance between slope changes
4.3 Radio altimeter operating area
In order to accommodate aeroplanes making auto-coupled
approaches and automatic landings (irrespective of weather
conditions) it is desirable that slope changes be avoided or
kept to a minimum, on a rectangular area at least 300 m long
before the threshold of a precision approach runway. The area
should be symmetrical about the extended centre line, 120 m
wide. When special circumstances so warrant, the width may
be reduced to no less than 60 m if an aeronautical study
indicates that such reduction would not affect the safety of
operations of aircraft. This is desirable because these
aeroplanes are equipped with a radio altimeter for final height
and flare guidance, and when the aeroplane is above the terrain
immediately prior to the threshold, the radio altimeter will
begin to provide information to the automatic pilot for autoflare.
Where slope changes cannot be avoided, the rate of
change between two consecutive slopes should not exceed
2 per cent per 30 m.
5. Runway surface evenness
5.1 In adopting tolerances for runway sufiace irregularities,
the following standard of construction is achievable
for short distances of 3 m and confoms to good engineering
practice:
The following example illustrates how the distance between Except amoss the crown of a camber or across drainage
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
附件14-机场 Aerodromes an14_v2_2ed(61)
