34:1 is not clear

前段时间被问到航图上的34:1 is not clear是什么意思。这个标记出现在安克雷奇的33号跑道RNAV(RNP)图上。

在网上海搜找了一下FAA的解释:

根据AIM 5-4-5条款关于VDP(Visual Descent Point)的定义,在非精密进近时,从MDA到接地端的一个目视下降点。但这个点只是参考,并不代表后续没有障碍物。当VDP之后,如果有障碍物突破了34:1的保护区时,就在航图上做一个标记,提醒飞行员注意。

在美国的航图说明中有这个的解释:

34:1 Surface Clear Stipple Symbol
On RNAV approach charts, a small shaded arrowhead shaped symbol from the end of the VDA to the runway indicates that the 34:1 Obstacle Clearance Surface (OCS) for the visual segment is clear of obstacles. The absence of the symbol indicates that the 34:1 OCS is not clear or a Visual Segment-Obstacles note is indicated on the chart.

Visual Decent Point (VDP)
The Visual Descent Point (VDP), is shown by a bold letter “V” positioned above the procedure track and centered on the accompanying dashed line. (See example below.) The VDP is a defined point on the final approach course of a nonprecision straight-in approach procedure from which normal descent from the MDA to the runway touchdown point may be commenced.

补一补VFR

忙完了IOSA审计,最近稍微空闲一点了。前几天在微信上看到了一个陆空通话的视频,讲的是米国一个从JFK到LGA的调机,没有发飞行计划FPL就开始运行了,机组向ATC申请VFR飞行规则。我对此比较惊讶,朋友圈里的飞行员告诉我,VFR运行可以不发FPL的。

视频链接:https://v.qq.com/x/page/k3023h75kkz.html

祖国的民航也都是建立在大飞机基础上的。国内的签派员都是院校培养,工作前一般都只有大飞机121运行相关的培训。对VFR知之甚少,包括我在内。所以关于这个问题,我想补一补课。

我看了一下FAA的要求:

AIM 5-1-4 Flight Plan – VFR Flights
Except for operations in or penetrating an ADIZ, a flight plan is not required for VFR flight. 
It is strongly recommended that a flight plan (for a VFR flight) be filed with an FAA FSS. This will ensure that you receive VFR Search and Rescue Protection.

再加上在B类和C类空域中可以运行VFR,所以视频中的调机的确可以。

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回头看看祖国怎么样呢?因为我想从JFK调机去LGA可以不发FPL,那么从PVG调机去SHA可否呢?至少从法律层面是否可以呢?

根据2018年11月16日发布的最新CCAR-91-R3《一般运行和飞行规则》分别有:

第91.153条 目视飞行规则飞行计划;
第91.169条 仪表飞行规则飞行计划;
第91.173条 空中交通管制许可和飞行计划。

91.153条和169条分别说的是目视飞行规则和仪表飞行规则飞行计划的内容要求,一个比较有意思的事情是,这两条都要求计划中包含机长的“姓名和地址”。这就有点意思了,因为FPL报中,可以附带机长姓名,但是从没见过附带地址。难道法规陈旧没更新?甚至我有点怀疑91部中的“飞行计划”是否是FPL了。如果先搁置这个问题,91.173条就有意思了。

第91.173条 空中交通管制许可和飞行计划
仪表飞行规则运行的航空器,应当按空中交通管制的要求提交飞行计划的申请,并获得相应的空中交通管制许可.

你会发现91.173条只要求了仪表飞行规则。没说目视飞行规则。

然后我又找了一下CCAR-93TM-R5《民用航空空中交通管理规则》:

第一百三十条 航空器驾驶员或者其代理人应当按照规定时 间在航空器起飞前向起飞机场的空中交通服务报告室提交经批准的飞行计划(领航计划申请表),其内容应当符合民用航空飞行动态固定电报格式(MH/T4007)的要求

似乎也没说目视飞行有什么特别的要求。

综上所述,我没找到明确说我国的目视飞行规则不需要发送飞行计划FPL。不过91.173条的描述也许暗示了这种可能性。(也许从来没人尝试过)

RUNWAY END IDENTIFIER LIGHTS(REIL)

这事是2014年发生的,今天在找灯光系统资料的时候,回忆起来。发现当时没有好好记录,现在补上。

此事源于一条通告:

A3368/14 VTSP E) RWY END LGT RWY 09/27 U/S

这条通告在“入口灯和末端灯”一文中也提到过。我曾经错误地以为,RWY END LGT和RUNWAY END IDENTIFIER LIGHTS是相同的灯。后来我发现两个东西不一样。

REIL不工作对落地标准没有影响。虽然它的名字叫“RUNWAY END”,但是其实它是面向进近一侧的。

FAA AIM : REILs are installed at many airfields to provide rapid and positive identification of the approach end of a particular runway.REILs may be facing the approach area.

我个人觉得它叫“RUNWAY EDGE IDENTIFIER LIGHTS”是不是更贴切一点?

 

关于相似航班呼号的问题

AIM 4−2−4. Aircraft Call Signs

When aware of similar/identical call signs, ATC specialists will take action to minimize errors by emphasizing certain numbers/letters, by repeating the entire call sign, by repeating the prefix, or by asking pilots to use a different call sign temporarily.

所以在空中是可以临时指定呼号的,以前一直记得可以的,现在找到出处了。

针对联程航班,如果把同一个航班号的航班分在两个飞机上,理论上可以出现在同一个区域,只要指定不同的呼号就行了。但这样的确给管制员增加了巨大的风险。

对面的跑道入口内移是否影响起飞落地距离Takeoff/Landing Distance With Double-Displaced Thresholds

内容有更正,见评论。

在执照考试时,说到跑道入口内移是否影响起飞距离?我以往的知识是,落地方向的入口内移,仅影响这一头的落地距离LDA。不会影响起飞距离TODA/TORA。不会影响对头跑道的任何距离。

但是有个考生给我一个例子:虹桥

DT2

DT1

对于18L/36R来说,物理跑道3400米,18L入口内移100米,落地距离应该为3300,但是细则里是3200米。起飞距离应该是3400米,但是细则里是3300米。这说明对头的入口内移影响距离!!!

但是反观18R/36L来说,物理跑道3300米,18R入口内移300米,落地距离3000米没错,起飞距离3300米也没错。说明对头的300米内移没有影响距离!!!

当时我就晕了。

我咨询了性能人员,以及自己找了国内的标准都没找到依据。

所以,按以往的做法只能去FAA或ICAO找找。

AIM Section 3. Airport Marking Aids and Signs

2. Displaced Threshold. A displaced threshold is a threshold located at a point on the runway other than the designated beginning of the runway. Displacement of a threshold reduces the length of runway available for landings. The portion of runway behind a displaced threshold is available for takeoffs in either direction and landings from the opposite direction.。。。。

FAA说的已经很明确了。

ICAO 附件14  3. Calculation of declared distances

3.5 Where a runway has a displaced threshold, then the LDA will be reduced by the distance the threshold is dis-placed, 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(双向) direction are unaffected.

ICAO也说得很明确了。所以我以前的理解没错。

至于为什么虹桥的入口内移会有那么奇葩的结果?有一种说法是,如果跑道入口内移是因为道面问题,就不能算做起飞距离。(只是传说)

说在最后,实际运行时,一切距离以AIP公布的为准。上文就当我瞎掰吧。

 

Duration of Microbursts

evo of a microburst

 

An individual microburst will seldom last longer than 15 minutes from the time it strikes the ground until dissipation. The horizontal winds continue to increase during the first 5 minutes with the maximum intensity winds lasting approximately 2−4 minutes. Sometimes microbursts are concentrated into a line structure, and under these conditions, activity may continue for as long as an hour. Once microburst activity starts, multiple microbursts in the same general area are not uncommon and should be expected.

常出现在雷暴的大雨区内,单个Microburst持续15分钟。连成片的Microburst可能持续1小时。

Low Level Wind Shear/Microburst Detection Systems

Low Level Wind Shear Alert System (LLWAS),Terminal Doppler Weather Radar (TDWR), WeatherSystem Processor (WSP), and Integrated TerminalWeather System (ITWS) display information on hazardous wind shear and microburst activity in the vicinity of an airport to air traffic controllers who relay this information to pilots.
a. LLWAS provides wind shear alert and gust front information but does not provide microburst alerts. The LLWAS is designed to detect low level wind
shear conditions around the periphery of an airport. It does not detect wind shear beyond that limitation. Controllers will provide this information to pilots by giving the pilot the airport wind followed by the boundary wind.
EXAMPLE:
Wind shear alert, airport wind 230 at 8, south boundary wind 170 at 20.
b. LLWAS “network expansion,” (LLWAS NE) and LLWAS Relocation/Sustainment (LLWAS RS) are systems integrated with TDWR. These systems provide the capability of detecting microburst alerts and wind shear alerts. Controllers will issue the appropriate wind shear alerts or microburst alerts. In some of these systems controllers also have the ability to issue wind information oriented to the threshold or departure end of the runway.
EXAMPLE:
Runway 17 arrival microburst alert, 40 knot loss 3 mile final.

LLWAS只能探测风切变。和TDWR结合后可以探测微爆下击气流。