转:X11 forwarding-基于SSH使用远程X-Windows应用

January 30, 2015

From: http://ift.tt/1yJVp2F

X11 forwarding-基于SSH使用远程X-Windows应用

(2012-03-02 17:48:58)

标签:

杂谈

真的不懂请看视频:http://ift.tt/SOzPx8
首先简单的介绍一下X 系统。 X 系统分为X server&X client部分,X server&X  client之间是通过XDMCP (X Display Manager Control Protocol)协议进行传输的。
x server 服务端负责处理和用户的交互,也就是图形的显示,键盘鼠标的输入等等.而客户端就是一个个应用程序。
其中服务端又分为2部分,一个是处理图形的显示单元,另一个是窗口管理器也就是处理应用程序的标题,边框等等的部分。
任何一个涉及xwindows的应用程序,在启动后都会发出tcp连接连往xserver的6000端口(默认得 0)xserver接受请求,通过认证后,就会负责该应用程序的界面。
这个模式哪怕是在本机都是如此。因此,x-windows具有极高的远程管理能力。
在win 下,常用的X server有 Exceed, X-win32等。
而ssh登陆工具我选择putty,体积小,功能强大,免费软件。(Xshell)
1, 打开X-win32, 通过x-config 设置Display number为 0. 此时 x-win32开始监听6000端口。
      如果你设置你的Display number 为1,那么监听的端口是6001,以此类推。
2, 打开putty
      在Connectin->ssh  选中Enable compression
      在Connection->ssh->Tunnels 选中 Enable X11 forwarding,X display  location中的设置要和x-win设置的 Display number 保持一致: localhost:0 或者(locaohost:1 )
( Connection->ssh->X11)
3,ssh登陆linux主机,然后输入 # xterm &
      你的win系统中就会弹出一个xterm的界面,你就可以通过xterm来操作远程的机器了。
    注意: 如果在x-config ->window中选择Multiple,否则选择single的话,如果不启动窗口管理, 你在putty中敲入的第二个xterm窗口会完全覆盖第一个xterm窗口。而在multiple模式下,每个xterm各占用一个独立的窗口,可以用鼠标进行控制,移动。
再次表示惊讶:putty这个小软件功能实在是强大。
ps: 1 要确定远程主机配置文件/etc/ssh/sshd_config是否有
     X11Forwarding  yes
         这一行;
   2  Exceed ,X-win32是商业软件。cygwin 带有免费的X-server
          运行cygwin,输入startxwin.bat 来运行X-server (可以用Xming)

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Sync to WP Test

January 1, 2015

Just a test

http://ift.tt/1AiR9w5

查看Windows详细版本号

November 20, 2014
  • Winver: 简略版

 

  • slmgr.vbs: 详细信息

    • slmgr.vbs -dli: 显示:操作系统版本、部分产品密钥、许可证状态
    • slmgr.vbs -dlv: 显示:最为详尽的激活信息,包括:激活ID、安装ID、激活截止日期
    • slmgr.vbs -xpr: 显示:是否彻底激活
    • slmgr.vbs -ipk: 更换Windows序列号  
    • slmgr.vbs -ato:  激活Windows

Excel 批处理 填充空白行

October 14, 2014
选中A1到A10,F5,定位条件--空值,确定
编辑栏输入:
=A1
ctrl+enter

中国十大最美公路

August 24, 2014
转:http://www.guancha.cn/life/2014_08_23_259706_s.shtml



不远行,永远不知道远方的景色有多美!如果某天时间和机会恰到好处,你千万不要错过下面或神奇或险峻,或梦幻或壮美的中国公路! 下面就是近日媒体总结的中国十大最美公路,不少网友感慨:美得令人窒息!此生一定要走一次!

NO.1 杭州湾跨海大桥
杭州湾跨海大桥是一座横跨中国杭州湾海域的跨海大桥,全长36公里。

NO.2 挂壁公路
挂壁公路是在悬崖峭壁上开凿而出的,我国一共有六条挂壁公路,主要分布在太行山及晋东南,有锡崖沟(陵川县)、郭亮(辉县)、陈家园(陵川县)、回 龙(辉县)、昆山、井底(平顺县)。其中郭亮被称为第九大奇迹世界最险要十条公路之一世界十八条最奇特公路之一

NO.3 终南山公路隧道
秦岭终南山公路隧道国家高速公路包头至茂名线控制性工程,也是陕西三纵四横五辐射公路网西安至安康高速公路重要组成部分。单洞长18.02 里,双洞共长36.04公里,建设规模世界第一,中国公路隧道之最,需15分钟才能穿越。为缓解驾驶员视觉疲劳,保证行车安全,特别设置了目前世界上高速 公路隧道最先进的特殊灯光带,值得一去。

NO.4 矮寨盘山公路

矮寨盘山公路,为国道319干线(旧称湘川公路)公路奇观。自下而上经13处弯道始达坡顶。山势陡峭险峻,近坡顶处有一公路天桥,全国罕见。山顶建有湘川公路死事员工纪念碑开路先锋铜像。

NO.5 矮寨特大悬索桥

矮寨特大悬索桥,位于湖南湘西矮寨镇境内。矮寨悬索桥,距吉首市区约20公里,跨越矮寨镇附近的山谷,德夯河流经谷底,桥面设计标高与地面高差达330米左右,全长1073.65m,悬索桥的主跨为1176m。该桥跨越矮寨大峡谷,主跨居世界第三、亚洲第一。
 
NO.6 天门山盘山公路

张家界天门山盘山公路有通天大道之称,盘山公路全长10.77公里,海拔从200米急剧提升到1300米,大道两侧绝壁千仞,空谷幽深,共计99个弯,180度急弯此消彼长,似玉带环绕,弯弯紧连,层层迭起,被誉为天下第一公路奇观

NO.7 二十四道拐

二十四道拐是个地名,是一段二十四道弯的公路,贵州晴隆“24道拐抗战公路,是史迪威公路的形象标识。古称鸦关,雄、奇、险、峻,有一夫 当关,万夫莫开之势。从山脚至山顶的直线距离约350米,垂直高度约260;在倾角约60度的斜坡上以“S”型顺山势而建,蜿蜒盘旋至关口,全程约4里。

NO.8 塔里木沙漠公路
沙漠公路南北贯穿号称死亡之海的塔克拉玛干大沙漠,对于渴望穿越塔里木沙漠的游客来说,塔里木沙漠公路无疑是提供了最好的条件,自驾车穿越整个沙漠,耗时将在5个小时左右,沿途可看见奇异的沙漠景观和千年胡杨。

NO.9 入藏公路

川藏、青藏、滇藏、新藏,四条入藏的公路风景都是极好的,是骑行者的天堂。其中川藏线是与国道318一部分,是中国的景观大道。

NO.10 苏花公路

苏花公路,是台湾东海岸的一条省辖公路,为省道台九线的一段,北方起点是宜兰县苏澳镇,南方终点是花莲县花莲市,临海道路全长118公里,大致依海岸线修筑,间或蜿蜒进入平坦河口三角洲腹地。沿路可看太平洋海景与峭壁山色,为世界著名的景观公路。

BIOS version command

August 9, 2014
wmic bios get smbiosbiosversion

Batch rename /w excel

July 15, 2014
  1. CMD –> DIR
  2. dir /b
  3. copy to excel
  4. A: old name, B: new name C: =CONCATENATE(“ren “,A1, ” “, B1)
  5. copy col C to txt, rename .bat
  6. run

How to Choose the Best Street and Track Brake Pads

July 7, 2014
http://www.essexparts.com/learning-center/cat/brake-pads/post/choose-brake-pads
by Jeff Ritter

Introduction

I’m going to share a little secret with you: As delivered from the factory, the brakes on your car are not capable of handling repeated lapping on a racetrack.  They’re also probably not very good for Autocross, drifting, or rally racing.  I don’t care if your calipers are painted red or gold, if you have gigantic carbon ceramic rotors, or if your car is advertised as being optimized on the Nordschleife.  Do you know why your brakes are not up to the task of a serious thrashing as delivered?  It’s the lowest common denominator rule.
In the US in particular, manufacturers try to make every car as accessible to as many people as possible.  That includes the guy who probably has no business being behind the wheel.  Despite the hardcore enthusiast’s wishes, that’s why you don’t see fixed-back race buckets in a stock Corvette, and why stiff, manually adjustable coilovers aren’t standard issue on a 911.  It’s much easier to push a button in the cockpit.  The same is true of your car’s brake system.  If a manufacturer delivered a ‘track-day special’ with an extremely noisy brake pad, there would be countless complaints and warranty-related service calls.  The Nissan GT-R is a perfect example.  The owner’s manual clearly states that the car has high-performance brakes, and that they could make some noise.  I was browsing one of the GT-R forums the other day, and of course there were a number people complaining about brake noise.  Go figure.
So, how do manufacturers address this problem?  They compromise, sometimes heavily.  The fundamental dilemma of taking a street car on a racetrack is that it was designed to do so many other things besides going as fast as possible.  A purpose-built racecar has no such identity crisis.  The brakes fitted to your car as standard are one of the most glaring examples of this dilemma, and they’re often the first vehicle system to wilt when leaned upon under heavy use.
What we want and need from a street pad is completely different from what we expect out of a race pad.  For day-to-day street driving, we’d all love to see our pads have the following attributes:

  • Never make any noise
  • No dust on our fancy wheels
  • Good cold bite on the way to work
  • Effective in the rain and snow
  • Last 100,000+ miles
  • Never wear out rotors

When the weekend rolls around however, our priorities shift.  We want our pads to have the following traits:

  • Enough heat capacity to never fade after repeated lapping on a racetrack
  • Predictable torque response for precise brake pedal feel and modulation
  • No required bed-in or preparation
  • Low compressibility for a rock-hard brake pedal
  • Immediate release from the discs when we let off of the brakes
  • No uneven pad deposits or scoring of the rotors
  • Little to no wear as heat increases

See any differences between those two lists?
Unfortunately, most manufacturers err on the side of caution, and prefer to make the stock brake pads as docile as possible for the street.  They know that one day your girlfriend or wife will take your Evo to the store, and she’ll tell you that there’s something wrong with your “screechy brakes.”  For the hardcore enthusiast however, the inherent performance compromises in OE brake pads are difficult to accept.
Therefore, our currently available options are as follows:

  1. Accept the sub-par performance of the factory pads during aggressive driving, and enjoy their docile manners around town
  2. Try to find a ‘happy medium’ pad that contains some attributes of both street and race pads
  3. Install a harsh race pad that performs well in motorsports but has no ‘street-friendliness’

So, we have some choices to make.  We must define the most important pad characteristics for the type of driving we’ll be doing, and choose a pad strategy with acceptable compromises.  We try to get as close to our happy medium as possible, based on how we use our car.  Every situation is different.

Basic Pad Composition

Before jumping into specific pad selection, let’s first take a step back and look at the bigger picture. Understanding the material composition of the four basic pad types, and how those materials behave on our cars, will substantially narrow the sensible choices for any given driving condition.
Brake pads for street cars typically fall into one of four categories. These categories are defined by the pad’s fundamental composition: organic, semi-metallic, ceramic, and sintered.
Organic
Organic pads are made of fibers mixed with fillers and binding resins to hold them together. Some components commonly found in organic pad are glass, Kevlar, and carbon. Organic pads have what enthusiasts consider a ‘mild’ character. They tend to be softer, easier on rotors, and they don’t make much noise. In the US, most OEM’s ship organic pads in new cars because they don’t require a lot of heat to generate friction, or bite. They are therefore safe for commuting in various environments. While these pads offer comfort, their Achilles Heel is a severely limited temperature range. Once they reach their maximum operating temperature, they almost immediately lose their coefficient of friction and burn up very quickly.
The materials used in these pads are the least costly to acquire, as are the tools and processes to manufacture them. Therefore, organic pads are typically the least expensive pad type.
Semi-metallic
Not surprisingly, semi-metallic pads get their name from their composition. Each friction puck contains a substantial amount of metal. Common ingredients are steel wool, iron, or copper, mixed with fillers, friction modifiers, and lubricants such as graphite. On the plus side, these pads have higher operating temperatures than organic pads, draw heat out of the rotors, and do not wear as quickly. On the other hand, they’re more abrasive and tend to wear rotors more quickly, make more noise, produce heavier dust, and many times have very little cold bite. Most race pads on the market today are semi-metallic.
Because the constituent materials, tools, and processes involved are more expensive than those used to produce organic pads, semi-metallic pads are more expensive.
Ceramic
The term ‘ceramic’ has been a hot marketing buzzword in brake pads for the past decade. These pads are created by mixing ceramic fibers, fillers, and bonding agents. The greatest benefits of ceramic pads are their lack of dust and noise. They tend to wear a little longer than organic compounds, and are also a bit more rotor-friendly. While they may have a higher temperature threshold than some of the organic compounds, they cannot compete with semi-metallic or sintered pads for heavy duty use. Enthusiasts who spend a disproportionate amount of time staring lovingly at their 6” polished rim lips may enjoy ceramic pads. Those who prefer to actually drive their car hard may be disappointed with the performance of ceramic pads.
Sintered
While sintered pads have been popular on motorcycles with steel rotors, they remain an emerging technology for automotive use. Most sintered pads are formed from a copper alloy powder. The powdered metal is mixed with other lubricating and wear controlling constituents such as graphite and carbon, formed into the required shape, and then brazed to a backing plate at temperatures as high as 1800 degrees F. ]
Sintered pads have some unique characteristics vs. other pad types. Their nearly pure metal content provides a stable coefficient of friction from cold to hot, meaning they often need almost no warm-up time to produce bite. Since they’re formed at extremely high temps, they don’t fade under extreme use. They also don’t create as much of a transfer layer on rotors, and therefore don’t require a lengthy, traditional bed-in procedure. Since the pads are semi-porous, they can be used in any weather condition: rain, snow, mud, etc.
Because they are mostly metal, the negatives traditionally associated with sintered pads have been increased rotor wear, noise, and the transmission of heat into the calipers.
The materials, tools, and processes involved with producing sintered pads are the most expensive of all current pad types.
The chart below provides a summary of expected pad characteristics based on the material composition. There are exceptions, but these are the general rules of thumb.

   Organic Semi-metallic Ceramic Sintered
Common Usage Street Race/Track Street Race/Track
Noise Low Moderate to High Low Low to High
Dust Varies High Low Varies
Judder Varies Varies Varies Low
Max operating temp. Low High Low High
Pad life Varies Varies Varies Varies
Rotor wear Low High Low Varies
Cold bite Moderate Low Low High
Judder/pad deposits Varies Varies Varies Low
Compressibility High Low Moderate Low
Cost Low High Moderate High

How Will You Drive Them?

Looking at the dissimilar ingredients in each pad type above, it should be obvious that they’ll perform quite differently as driving conditions change.  The underlying components dictate each pad’s basic operating parameters.  If you ran a piece of chalk down the side of your car, would you expect identical results when doing the same thing with your house key?  Of course not.  It’s not any more reasonable to expect an organic pad to last forever at 1200 degrees F, or a semi-metallic pad to run silently against an iron rotor.
Each pad has its ideal operating conditions, which may or may not fit your driving style, habits, or requirements.  So how do you choose the pad that’s right for your situation?  You compromise, beginning with your top priorities and working your way down to the traits that aren’t as important to you.
Let’s take a look back out our initial bulleted list of desirable characteristics for the street and track, except this time we’re not going to isolate the street from the track.  Instead, we’ll blend the lists together into one abbreviated attribute list:

  • No uneven pad deposits, judder, or vibration
  • Low noise
  • Low dust
  • High max operating temperature (fade resistance)
  • Good cold bite
  • Long rotor life
  • Effective in all weather conditions
  • Good hot bite
  • Long pad life
  • Predictable brake torque response
  • No bed-in
  • Low compressibility
  • Immediate release

Now we’ll take a look at each of the scenarios you may encounter behind the wheel, and examine which characteristics are the most desirable or important for that type of driving.  The goal of this article is not to dictate the perfect pad choice to you.  The objective is to get you thinking about as many of the factors that go into pad selection as possible for your unique situation, which should help you make an informed purchase decision. 

Daily driver shared vehicle

If you share your street/track car with a significant other, save yourself some headaches and go with as mild of a pad as you can stomach.  Unless you can find a quiet sintered pad, organic or ceramic pads are your only logical options.  You’ll have to accept the fact that your favorite toy has become a glorified taxi and shopping cart.  For this situation, important attributes from our list above include:

  1. Good cold bite– When you hit the first stoplight on the way to work in the morning, you want the car to actually stop.  Standing on the brake pedal and praying is a terrible way to start the day, and it’s even less fun for the person you just rear-ended.
  2. Effective in all weather conditions– Assuming you don’t live in Southern California, having a daily driver that can slog through rain, snow, and dirt without compromising performance is important.
  3. Low noise– If the pads on your shared vehicle are noisy, you may be sleeping on the couch. When the average schmuck who knows nothing about cars hears your S2000’s squealing brakes and asks, “What’s wrong with your car,” you find it amusing. When they ask your wife for the fifth time, she may lose her mind.

You could argue that long wear rates and predictable response are both important to economical street driving.  For the most part however, appropriately handling the three issues above should keep all involved parties relatively safe and happy.
The pads required to accomplish these feats very closely resemble the OEM pads found in most US passenger cars.  These are the issues on manufacturers’ minds when they decide on a pad compound.  They want to make the brake system as idiot-proof as possible, avoid all warranty claims for noise and vibration, and ensure that even the most careless won’t hurt themselves while driving their mobile phone booths.
If you want to drive your shared car aggressively on country roads, canyons, or in any type of motorsport event, buy a nice jack, ramps, and some hand tools, because you’re going to be frequently changing your pads to get the performance you’re after.  Using a pad geared towards solving the most basic transportation needs doesn’t exactly provide a broad performance envelope.
If you try to take this type of pad into an aggressive driving situation, you’ll encounter pad fade, lack of bite, poor modulation, and accelerated pad wear as temperatures rise.  You may even trash your rotors with uneven pad deposits.
If your significant other isn’t too vain, you may want to talk her into an inexpensive beater for daily driving duties.  For the price of a nice set of wheels, you can buy a car that gets solid gas mileage, provides reliable transportation for many miles, costs almost nothing to insure, and you won’t even have to worry about door dings.  Implement the beater lifestyle, and your newly converted track-only toy will thank you.

Daily driver & Aggressive Street Driving

Many enthusiasts fall into this category.  You drive your car on the street to work each day, to run errands, and out to dinner when you feel like stroking your ego a bit (although you rarely allow the valet to touch your car…and you watch him like a hawk when he does).  You take every opportunity in the evenings and on weekends for a spirited drive off the beaten path.  You’d like to get into motorsports, but you’re either unsure how to do so, have a severely limited budget, or a complete lack of time.
When we throw aggressive driving into the mix, we have to deal with higher brake temperatures.  While organic pads could be an option, semi-metallic or sintered pads are the smarter choice.

  1. Good cold bite- Even though you use your car for ‘fun’ driving in addition to daily duties, your safety is the top priority.  It’s still critical that your brakes bite cold on the way to work each morning
  2. Effective in all weather conditions- As with cold bite, you’re again constrained by daily driving requirements.  If you live in Phoenix, enjoy that ‘dry’ July heat, and don’t worry about this issue.  If you dwell where the sun doesn’t shine…ahem, sintered pads could be your best choice.
  3. High max operating temperature– If you ever hammer your brakes on country roads or canyons in your spare time, it’s entirely possible to get pad fade (firm brake pedal, but the car doesn’t stop).   See point #4 below if you only plan to get your brakes really hot “once in a while.”
  4. No pad deposits, judder, or vibration– The propensity for uneven pad deposits, or what many people call “warped rotors,” increases dramatically when you plan to drive your car hard at times, but err towards a milder pad compound for comfort.   You think to yourself, “Well I’m only going to get them really hot once in a while.”  Whether done once or twenty times, organic compounds tend to smear on the rotors when pushed towards their maximum operating temperature, sometimes causing irreparable damage to both the rotors and pads.  Yes, you can ruin your rotors the first time this happens, a costly lapse in judgment.  Don’t be the guy who says he’ll only try crack once.  If you plan to bomb away on your pads once, you’ll do it more than once.  If you think you’ll ever push your pads to a temperature above the recommended range for a given compound (even once), go with a compound capable of handling those higher temperatures.

You’ll now have to decide if it’s worth the additional noise, dust, and possible loss of cold bite to step up to a semi-metallic pad.  If you go with semi-metallic’s, research their cold bite before purchasing.  Or, if you can find a low noise sintered pad, that would be acceptable as well, particularly if pad deposits are a concern.  If you stick with an organic compound for comfort reasons, you must be mindful of brake temps.  Backing off before you actually experience substantial pad fade can mean the difference between a fun drive and ruining your pads and rotors.  If you have the experience to read the signals of an impending problem, feel free to ignore this advice.  Otherwise, suck it up and deal with a little noise and dust you big baby.
Please keep in mind that there’s almost always more than one solution to the same problem.   In the above scenario, rotors that flow more air or brake ducting could both potentially lower pad temps enough for the use of a milder compound.  These solutions work towards the same objective of lower overall brake system temperatures.  To minimize compromises, look for different routes to the same objective.

Weekend Warriors

Most serious enthusiasts begin with aggressive street driving, but eventually make the leap to some form of motorsport on weekends.  They do so when they either have enough money to continually replace consumables such as brakes and tires, or when they become frustrated with the limited driving experience public roads offer.  Because of the prohibitively high costs of storing and transporting a dedicated track car, the majority continue to drive their ‘fun’ car on the streets.  Although over time, the car gradually becomes a different creature, one that is less comfortable, louder, faster, and much happier on a track than on the street.
With some motorsport experience under your belt, you likely find yourself driving slower and more sanely on public roads.  You realize that you’ll never be able to replicate your track driving style without killing yourself or someone else.  Driving fast on the road just doesn’t do much for you anymore.
At this point, many enthusiasts adopt a multiple brake pad strategy, one for the street, and one or more pad compounds for various motorsport venues.  The street pad choice is now geared mainly towards comfort, although some still enjoy a quick blast down a deserted road.   Most of these customers know when to back off however, and can recognize when damage to their limited street setup is imminent.
Let’s take a look at the various motorsport venues for which dual-use street and track cars are commonly used, and examine the brake pad requirements for each.

Drag Racing

Unless your car is on the verge of needing a parachute at the end of a run, any decent aftermarket pad should be able to handle one substantial stop from a relatively high speed.  That said, I’d place good cold bite as my highest priority, particularly if you’re driving a sub 11 second car like Vinnie Diesel.  That means organic or sintered pads are your best options.  Waiting around for your pads to bite when doing 130mph+ at the end of the strip is a pucker-factor 13, so I’d steer clear of ceramic pads, and be sure the semi-metallic’s you’re considering have good cold bite.

Autocross

Autocross presents a unique challenge for your car’s brakes.  Depending on the course layout, the amount of pad heat generated may not be any greater than driving through stop-and-go traffic.  Many times you never get out of second gear, which means speeds are generally limited to 60mph or less (yes, I know your Viper does well over 60mph in second).  Additionally, the flowing nature of a well-designed autocross course means that you don’t scrub off a tremendous amount of speed entering each brake zone.  More often than not, you’re trail braking as you approach the apex of the corner, rather than standing on the brakes in a straight line.  Therefore, precise control and feedback is what you’re looking for in a pad:

  1. Good Cold Bite- In autocross, you don’t have many chances for the perfect run.  Just as with tires, you need immediate response from your brakes when you approach the first turn on the course.  If the pads need heat to bite, you’ll push your way into the first turn, and stutter into turn six as the pad heat builds.
  2. Predictable brake torque response- Ideally, your brakes will feel exactly the same on the first stop as they do on the sixth stop, allowing you to smoothly enter each corner under braking.
  3. Effective in all weather conditions- Autocross season usually starts in March, and in many areas of the country it’s not surprising to see a light snow or rain at the first few events.   Having pads that work in these conditions certainly won’t hurt your cause in the season point standings, and will certainly give you the drop on fair weather competitors.
  4. No Bed-in– Properly bed-in pads and rotors add a substantial amount of control, which is critically important in Autocross.  While driving your car around on the streets you’re gradually wearing off your pads’ bed-in transfer layer.  A pad that doesn’t require a complicated bed-in procedure could be a big time saver and give you a competitive edge.

Due to the nature of the braking events, we don’t really see many heat-related brake problems at autocross.  Therefore, fade and uneven pad deposition can be eliminated from our requirement list.  If winning carries any weight with you, noise and wear should not be considerations.  If you’re worried about dust on your wheels, wait until you try getting all of the tiny shoe polish bits out of the corners of your windows.  Magnetic numbers are your friend.
Organic or ceramic pads could offer the desired results at Autocross, but may not have enough response or feel to satisfy the discerning driver.  Additionally, most of these pads require a thorough bed-in and constant maintenance of the transfer layer to operate at their peak level.  If you can find a semi-metallic with good cold bite, you’ll probably be happier.  Even better, a good sintered pad could address all of the critical requirements for a solid Autocross pad.
As mentioned earlier, you should explore various solutions when setting up your brakes for autocross.  With some organizations, slotted or drilled rotors may not bump you to a different class, but they can add additional pad bite and control when trail braking.  Stainless steel brake lines could also give you improved pedal response and feel.  Reduce compromises by exploring multiple solutions to the problem at hand.

Gymkhana

Gymkhana is a timed event on a closed course, which most Americans immediately liken to autocross.  Similar to autocross, speeds tend to be lower in Gymkhana, with a focus on car control and precision.  Some would argue that gymkhana events are even more technical however, as they demand the mastery of a different set of car control skills such as drifting, spins, etc.  As we saw with drifting, the popularity of US Gymkhana is being fed from Japan, where it has been popular and competitive for many years. 
Brake requirements for Gymkhana closely mimic Autocross needs, with cold bite and predictable all-season response emerging as the most important requirements.  A semi-metallic pad with good cold bite, or a sintered material would be the best pad options.

Drift

In the past few years a number of big brake kit manufacturers have targeted the drift crowd for advertising.  Let’s clear something up.  The notion that fifteen inch rotors and twelve piston calipers will improve your drifting is just plain foolish.  Big brakes are required when the primary objective is reducing brake system temperatures.  Adding a gigantic brake kit to a drift-specific car is akin to perpetually having an import model riding shotgun.  Your car will always look better, but you’ll be continually dragging around dead weight and spending more money than you should.  Tsuchiya-san would surely smack you with his finger pointer if given the opportunity.
Many of the techniques used to initiate a drift have little to do with the brake pedal.  As such, brakes play a supporting role, rather than a starring role in drifting (with the exception of the hand brake).  Controlling your car’s weight transfer is crucial for effective drifting.  As such, control is a higher priority than heat capacity.

  1. Good Cold Bite- As with autocross and gymkhana, you don’t have many chances for the perfect run in competitive drifting, and you don’t have all day to wait for your brakes to warm up.  The goal is to shift weight quickly and smoothly, and a pad that bites hard cold is a boon.
  2. Predictable brake torque response- As with road racing, repeatability is critical in drifting.  If the car enters a drift the same way every time, your ability to get creative increases dramatically.  You know what the car will do in response to your inputs.  You want your brakes to feel exactly the same at all times when making attitude adjustments to the car with the brake pedal.
  3. No Bed-in– Properly bed-in pads and rotors add a substantial amount of control, which is paramount in drifting.  While driving your car on the street with cold brakes, you’re continually wearing off the pad transfer layer on the rotors.  A pad that doesn’t require a complicated bed-in procedure saves time and provides a competitive advantage.

Although you’ll likely give your brakes more of a workout in drifting than you would in autocross, you don’t need the pad with the absolute highest maximum operating temperature on the market.  Then again, you also don’t want something that wilts as soon as the heat gets ratcheted up.  If you go with a mild organic pad, you do run the risk of fade and uneven pad deposition.  Wear isn’t really a consideration unless you have a BBK, in which case new pads and rotors may cost more than the replacement value of your 240.  If the dust on your Volks bothers you that much, use more Zaino you pansy.
Organic or ceramic pads probably don’t have enough feel to satisfy the driver with a sensitive foot.  Additionally, most of these pads require a thorough bed-in and constant maintenance of the transfer layer to perform optimally.  A semi-metallic or sintered pad with good cold bite would be the ideal choice.
As mentioned earlier, you could evaluate slotted, drilled, or dimpled rotors to gain some additional pad bite and control.  Some people like the feel of these rotors, while others find the grittier feel through the pedal distracting.  Stainless steel brake lines offer improved feel, and don’t forget to regularly flush your brake fluid to maintain the most solid pedal.  Brake fluid constantly absorbs water over time, even under ambient conditions.

Show

I threw this one in under motorsports for all of my show car friends, because I didn’t want them to feel slighted.  Seriously though, you really want my advice on which brake pads to use for your show car?  How about the ones with the chrome backing plates and Hello Kitty stickers?  Don’t just sit there looking at it, play with it!  Friends don’t let friends have cars that are all show and no go.

HPDE (High Performance Drivers Education)

Unless you flagrantly risk your life at every turn, you’ll never put the same amount of heat into your brake system on the street as you will on a road course.  HPDE is really the first venue I’ve mentioned thus far where maximum operating temperature and fade resistance come to the forefront as the critical brake pad requirements.
One of the most interesting aspects of HPDE is the wide range of speeds and driver ability across run groups.  As such, it’s difficult to recommend a blanket pad compound or type for HPDE.  After countless discussions with customers on this topic over the years, I believe there a few key considerations when selecting a track pad: Driver experience, track layout, vehicle configuration/modification, and tire choice.  A careful examination of these factors in your personal situation should lead you towards an acceptable pad choice.  Keep in mind that all of these factors are related, and cannot be considered in isolation from one another.
Driver experience
If you’ve never driven anywhere but the street, your first couple of trips to the track will most likely not tax your brake system too heavily, right?  Not exactly.  If you’re driving a twin turbo Viper on R compound tires at Road America, you’re going to have some serious problems with a bone stock brake setup.  A blind chimp could obliterate the brakes under those circumstances, so you being a complete track newbie won’t necessarily protect your brakes from destruction.
It’s true that novice drivers tend to be easier on the brakes because their corner exit speeds are lower, their terminal speeds entering brake zones are therefore lower, and there’s less kinetic energy being transferred into heat during a given stop.  That said, novice track drivers also tend to stab wildly at the brakes, stay on the brakes too long, oscillate between on and off brake, and do all sorts of other things you never seem to expect from the passenger seat!  The end result can be some serious brake punishment.  It’s impossible to say that a novice driver will be fine on stock brake pads based on track experience alone.
Track layout
Long straights followed by tight turns mean your car is decelerating from a very high speed to a very low speed, creating a high energy stop.
The distance between stops will also impact the heat retained in your brakes.  If a particular track layout has a steady succession of medium straights and tight turns, your brakes don’t have much time to cool between stops.  That means heat will continually build.  Flowing tracks with long sweepers are much easier on brakes (think Willow Springs).
Look closely at the track you’ll be driving to determine how demanding it will be on your pads.
Vehicle configuration/modification
Power to weight ratio, drivetrain layout, and other brake system components all factor into pad selection for track duty.  All else held equal, more massive, faster cars place a greater strain on the brake system in a brake zone.  An Audi Allroad will require a much larger rotor as a heat sink than a Miata.
 If you strip 200lbs. out of your car, you’re placing less demand on your pads in terms of mass, but you’ll be hitting higher speeds entering turns.  For a given amount of power, lighter cars are easier to accelerate, and will reach a higher speed at the end of a straight.
Front engine cars are much harder on front brakes than they are on the rears.  If you drive a 911 or NSX, your car uses comparatively more rear brake than a Viper, which has a massive V10 sitting over the front wheels.
If your car has large rotors and fixed (non-slider) calipers from the factory, is fairly lightweight with lower power (think DC5 Integra Type R), your pads will be much less stressed than on a heavy, powerful car with undersized factory brakes (base model 350Z).
The interplay of vehicle power, mass, weight distribution and the overall brake package will all substantially impact pad choice.
Tire choice
Tire choice is one of the single greatest factors in determining which pad will work for you on the track.  The stickier the tire, the more brake you can use, and the more heat you will generate.  More grip = more heat.  If you’re running street tires, or if it rains at an event, you won’t be able to generate as much grip, and you won’t tax your brakes as much.  Maybe you really don’t have to pull off your wheels to swap pads in that downpour!
So where does all of that leave us when choosing a pad for HPDE?  The critical point is, every modification you make to your car and the nut behind the wheel will change the demands on your brake system, and you must adjust accordingly.  Just because you used a particular pad before, doesn’t mean it will work again after you’ve installed your new turbo kit and Hoosiers.  Chances are that after your 25th event, you’ll be taxing your brakes very differently than you did during your first event.  You’ll be hitting higher speeds, entering and exiting corners faster and in a different way, and your car will likely have more grip and power than it did when you started (you’ll also be much poorer).  As such, you must constantly evaluate the overall condition of your brake system, and not be afraid to try new pad compounds as both you and your car evolve.
If you want to play it safe and not risk damage to the major components of your brake system, don’t EVER drive an OEM pad on a road course.  It may be more convenient and seem economical to run stock pads, but it will cost you time and money in the long run.  There’s also not much worse than wasted track time.  When you’re sitting in the pits watching your buddy rip down the front straight, and your stock pads are a steaming pile of dust lying inside your wheels, you’ll be wishing you took the hour on Friday night to change your pads and bleed your fluid.  I can assure you that they weren’t designed to cope with the stress of an HPDE event.
So, what pad attributes are critical for HPDE?

  1. High max operating temperature– Pussyfooting around a track while nursing fading brake pads is incredibly frustrating, but slamming into a barrier after your brake pads have completely lost all grip on the rotors is slightly more upsetting.  Evaluate the parameters of your situation as described above, and make sure you have pads that will handle the heat you plan to throw at them.
  2. No uneven pad deposits, judder, or vibration– Although some pads may have problems in this area at moderate temperatures, this attribute often goes hand-in-hand with a High max operating temperature.   You do not want a pad that readily smears high spots of material onto your rotors.  Entering every turn with a thump-thump-thump through the brake pedal and steering wheel is extremely distracting, and could waste your hard-earned track time, your rotors, and a sizeable stack of cash.
  3. Predictable brake torque response- If you want to increase your driving skill and graduate to the next level, consistency will take you there.  Brake pads that feel the same in every brake zone will go a long way towards improving your lap times and comfort on the track, as your mind will be freed up to focus on other things.

Although not critical, these are some other important attributes for HPDE:

  1. Good hot bite– To a large extent, this is a matter of personal preference.  Most pads with an adequate Max Operating Temp for the track have at least decent bite.  That said, the coefficient of friction of race pads is all over the map.  I’ll discuss this topic a bit more in the next section, but most HPDE drivers enjoy a pad that requires only a modest pedal effort to produce tangible results.
  2. Long pad life/Long rotor life– Your budget will completely dictate the importance of this issue, but the bulk of my customers don’t have $500 to burn up during every 20 minute track session.   You’ll have to find a pad that offers a balance of wear along with the characteristics you’re after.  A milder pad may be gentler on your rotors, but will burn up more quickly as the temps increase.  A pad with ultra high bite may feel great, but it may chew your rotors up quickly.  Tradeoffs, tradeoffs.

Good cold bite isn’t really a huge issue in HPDE.  Your warm-up /recon lap under yellow flag conditions is the perfect time to bring your pads up to temp, and in HPDE you’re not running for a time on lap number two.
While driving on the track in the cold, rain, and snow is definitely entertaining, it’s not the norm with HPDE’s.  Most sanctioning bodies delay or postpone events for adverse track conditions, so all-weather effectiveness isn’t typically a prerequisite for a great HPDE pad.
When preparing your car for the track, you must take the time to bed-in your pads.  Assuming you’ve accepted this fact, a pad that requires little or no bed-in would not be a critical performance advantage.  It would however be a tremendous convenience.
Low compressibility and immediate release are nice-to-have’s, but probably outside the scope of many HPDE drivers’ concerns.
If you’re worried about noise and dust while tracking your car, maybe you should just stick with knitting or coin collecting Sally.  You’re probably the same guy that uses two full rolls of painter’s tape on your front bumper.
Semi-metallic and Sintered pads are the only reasonable choices for track duty.   Organic and ceramic pads will rapidly turn to dust or melt, trash your rotors, and waste valuable track time.

Time Trial / Time Attack

If you’re competitively driving your car against the clock on a road course, you hopefully have a fairly solid handle on the capabilities of both yourself and your car.  As such, your priorities for brake pads may shift above and beyond the critical necessities described in the HPDE section.  At this stage you begin to evaluate the nuances of a pad compound.
I briefly touched on the generic topic of a pad’s ‘hot bite’ in the last section.  For the seasoned driver, how the pad bites when hot is a very personal and important attribute.  Some pads have a completely flat torque curve: as temperatures rise, the pad’s coefficient of friction remains constant and stable.  During a stop, you feel this through the pedal.  As you progress through a given braking event, you progressively push the brake pedal harder to slow the car “more.”  For many people, it’s the only logical and ideal response out of a pad.  They find it easier to adjust the car’s cornering attitude by modulating the brakes with a linear leg effort…pushing harder means “go slower” or “stop!”
Others prefer a pad with a rising torque curve.  As heat progressively builds during a stop, the pad’s coefficient of friction ramps up as well.  This type of pad requires a more constant, or even diminished, leg effort as you progress into a turn.  The pads bite harder without much change to the force input.
The most obvious way to evaluate these characteristics prior to purchase is via a compound’s brake dyno plot.  Unfortunately, most manufacturers don’t publish this data.  Additionally, the methods used to collect and display dyno data is non-standardized.  Therefore, the customer is presented with the classic dyno dilemma as witnessed in countless message forum wars regarding engine power.  Brake pad dyno plots from different manufacturers should not be compared directly.   Instead, they should only be used to provide general guidance on the shape of the Mu curve for a given pad compound, or to compare compounds within a particular manufacturer’s available range.
In addition to Mu, advanced drivers take notice of other pad characteristics such as compressibility.  Given the vast array of materials used to create brake pads, it isn’t at all surprising that certain pad materials are more pliable, malleable, and compressible than others.   If the primary components of organic compound A are newt eye and bat wing, it’s going to feel a little more ‘squishy’ under foot than pad B made from nearly pure iron.  Again, this is a matter of personal taste.  Some drivers spit venom if they feel even the slightest bit of slack through the brake pedal.  As with Mu, there’s no easy way to identify a compressible pad prior to purchase.  You’ll have to rely on personal experience or the experience of others for guidance. (Note: If you bleed your aftermarket big brake kit six times and something still doesn’t feel sharp when braking hard on the track, don’t overlook a compressible pad material as a potential culprit.)
As with Mu and compressibility, release is a term you hear thrown around quite a bit in race pad discussions.  A pad with poor release continues to ride the rotor after the brake pedal is released.  The pads feel ‘sticky,’ and won’t let go of the rotors as you trail brake into a turn.  As with compressibility, you’ll have to discover which pad compound suits your taste in this regard through experience or recommendation from a trusted source.
For the competitive time trial or time attack driver, experience and a detailed analysis of the driving environment will be core determinants in choosing the appropriate pad compound.  It’s obvious that a semi-metallic or sintered compound with a high max operating temperature and predictable response is critical.  After that, it gets tricky.  Relying on the subjective opinion of friends, competitors, and experts to describe the subtle nuances of a given pad can be helpful, but don’t be surprised if your reaction to the pads is completely different when you try them for the first time.
Because of their format, certain time trial and time attack events do offer the opportunity to exploit a competitive advantage through brake pad selection.  Some organizations run a format of one warm-up lap, followed immediately by a very limited number of hot/timed laps (one to three), culminating with a cool-down.  Just as with autocross, a brake pad that doesn’t need a substantial amount of heat to provide stable maximum friction can provide a great advantage.  In this regard, a sintered pad has the advantage over other pad types.

Wheel-to-wheel road course sprint & endurance racing

Only a select group of individuals have the intestinal fortitude to rip a street car to pieces and turn it into a full-blown racecar.  It takes some serious courage to weld in a cage and go speeding around a track six inches from a guy you’ve never met before.  If you crash, you lose a lot of money.  If you ever try to sell the car, you lose a lot of money.  If you win, you lose a lot of money but you feel good about it.
Plenty of people in the PCA race their 911’s and continue to drive them on the street.  Most of these individuals simply leave their race pads in the car at all times, since the car is typically a weekend toy.  On the rare occasion the car sees street action, they’re happy to deal with the screeching, dusting, and complete lack of cold bite found in many semi-metallic race pads.  In many of these situations, the car is even trailered to events, so there’s not much concern about street manners.
The critical requirements for a good full race pad mimic those for time trials or time attack.  The only notable exception would be the need for superior pad wear when endurance racing.

Rally /Hill climbs/Rallycross

The variables and challenges in rally-related events are probably the most complex across all motorsports, and the drivers who excel in these venues are arguably the most versatile and talented.  Most notably, track conditions in these events are much less controlled vs. other types of motorsports, and having a single solution for all occasions is virtually impossible.  Drivers may encounter tarmac, dirt, mud, snow, ice, and water during these events.  Each of these surface conditions prevents unique grip levels and brake requirements, and these surfaces are not always encountered in isolation from one another.  For example, a car may encounter split-mu conditions, such as braking with the driver’s side tires buried in loose gravel, while the passenger side tires are clawing for grip on ice.  The ramifications of these complex conditions are outside the scope of this article, but there are some basic desirable traits for brake pads if you plan to take your STi, Evo, or 323 GTX to one of these events.

  1. Good Cold Bite- You need pads with high bite on the first stop, and every stop thereafter.  You may also have sizeable distances between heavy brake applications, which allow the pads to cool considerably.  Good cold bite is a must for rally-type motorsports.
  2. Predictable brake torque response- With ever-changing track conditions, you always want to know what the car will do in response to your inputs.
  3. Effective in all weather conditions- A pad that can predictably perform when covered in water, snow, and mud is a huge advantage in rally events.
  4. No Bed-in– Not having to bed-in pads or maintain a transfer layer is a tremendous advantage as event conditions change.

While this list mimics the requirements for autocross, the speeds associated with these types of events are normally higher.  As such, ensuring that the pad you choose has a High Max Operating Temperature is also critical.  Organic and ceramic pads are not really appropriate for these types of events.  Some semi-metallic compounds may work well, but sintered pads will provide the most driver advantages due to their versatility during changing conditions.
It’s extremely unfortunate that rally racing has never gained a sizeable mainstream acceptance or following in the US.  Even during its Group B heyday of the early ’80’s, it never drew the audience that the juggernauts of F1 and NASCAR do today.  Regardless of past public reception, if you’ve never watched Sebastian Loeb hit a jump, graze some crazy spectators, and narrowly dodge four trees larger than telephone poles all while sipping a latte, you really should.  I still can’t figure out how that guy fits his gigantic brass pair into a standard issue race bucket.

Overall most important vs. least important attributes

So now that we’ve combed through most of the ways in which we’ll potentially use our street/track car, which of the brake pad attributes from our list repeatedly came to the surface as being critical?  The ones that allow us to go faster and enjoy our car more with less hassle of course!

  • Good cold bite
  • Predictable brake torque response
  • No uneven pad deposits, judder, or vibration
  • High max operating temperature (fade resistance)
  • No bed-in
  • Effective in all weather conditions

As a serious enthusiast, you’re likely the competitive type who wants the best performance.  Pads with the above performance attributes are not the cheapest to manufacture, are quite often specialized in their application, and probably aren’t the best choice for your wife’s car.  If performance is your priority, you’ll have to compromise on comfort and cost, which you’ll notice rarely made it to the top of our priority list.  These attributes are only important to manufacturers making a pad choice for the average Joe, and they likely hold little relevance to the type of driving you most enjoy:

  • Low noise
  • Low dust
  • Long rotor life
  • Long pad life

The grids below summarizes the important pad attributes by driving venue.

Daily Driver Canyons Drag AutoX/Gymkhana Drift
Good cold bite Good cold bite Good cold bite Good cold bite Good cold bite
All weather All weather Predictable response Predictable response
Low noise High MOT All weather No bed-in
No Judder/deposits No bed-in


HPDE Time Attack Wheel to wheel Rally/Hill
High MOT High MOT High MOT Good cold bite
No Judder/deposits Good cold bite Good cold bite Predictable response
Predictable response No Judder/deposits No Judder/deposits All weather
Good hot bite Predictable response Predictable response No bed-in
Good hot bite Good hot bite


If you try taking what appears to be the cheap and easy route of using OEM or low cost aftermarket pads for performance driving, don’t expect a favorable experience.  You’ll have poor performance, and it will probably cost you more money and time in the long run than if you initially bought the proper tools to match your needs.
Ask yourself how much time you spend in each of the driving scenarios we examined.  Do you use your car 98% of the time for daily driving, and only take the car to the track twice a year?  In that case, it’s probably worth the time to swap pads for the rare motorsport event.  A good set of track pads is a great investment that will likely last you multiple years in this scenario.
On the other hand, if you’re competing in autocross twice a month, time attack once a month, and canyon driving weekly, you’ll either have to buy dedicated pads optimized for each driving environment, or you’ll have to choose a pad that works fairly well for all of these scenarios.  Just accept the fact that you will have to make some compromises in comfort, cost, convenience, or performance.

Closing comments

Every time I see a lazy newb on a car forum toss out the innocent, “what’s the best brake pad?” question without providing any information about how they actually plan to drive their car, I brace myself for  the inevitable mind-numbing fanboy brand warfare that ensues.  As you can hopefully see, there is no one best pad or brand for all people in all situations.  Pads are largely a personal preference based on usage requirements.
While you should now be able to quickly assess a pad’s basic performance envelope by knowing what it’s made from, realize that there are exceptions.  Don’t be too hasty to immediately eliminate an option based on its composition alone, and please don’t be afraid to experiment and try something different.  That’s why God created eBay and the message forum marketplace.  What may not be ideal for your situation is probably perfect for someone else.  I feel bad for people who find something that always stick to what “works well enough.”  How do you know that something else won’t suit you better?
Most serious enthusiasts have tried a wide range of compounds, and have developed at least some sense of what they do or don’t like in a pad.  This is where the real fun begins.  Driving style and the appropriate product characteristics converge, allowing the driver to explore the car in new and different ways.  At this stage you’ll also be able to put into words more clearly what you’re feeling with a given pad.  Things like a rising torque curve or poor release will become more obvious with a broader base of comparison under your belt.  While these terms will certainly confuse the hell out of your neighbor in a casual conversation, they will help you gain better advice and guidance from other drivers, racers, and industry professionals.
Take a serious look at your unique situation, assess your needs, and be prepared to compromise if you plan to use your car in more than one driving environment.  The one-size-fits-all approach has never been a viable option in the brake pad market, nor will it be with the current technology in hand.  Choosing ‘the best’ brake pad will be a unique process for every enthusiast based on their unique wants and needs.

Crazy Ivan

April 16, 2014
转:http://club.china.com/data/thread/12171906/2715/57/91/5_1.html

1987年9月13日,巴伦支海上空,挪威空军第333飞行中队的扬•塞尔维森机组驾驶的P-3B型反潜巡逻机,正在苏联沿岸执行侦察任务。10时 39分,该机与一架过去从未见过的苏联新式战机遭遇,10时56分,在距苏联海岸线48海里处,这架苏军战机第3次逼近P-3B,在稍加调整位置和方向 后,猛然加力,从P-3B的右翼下方高速掠过,用垂直尾翼在P-3B的右外侧发动机上划开了一个大口子,P-3B的飞行高度在一分钟内掉了3000多米, 在坠海前的最后一刻才侥幸改平,而苏联战机因为垂尾损坏很快返航。这就是冷战时期著名的“巴伦支海上空手术刀”事件,那架神秘的苏联战机,就是日后大名鼎 鼎的苏-27,而这次冲突,被作为最著名的苏军空中撞击战例载入史册。
      红星喋血卫国战争
      “巴伦支海上空手术刀”事件,是迄今为止苏联/饿罗斯军队进行的最后一次空中撞击作战,而苏军最早的空中撞击战例,可以追溯到66年前的1941年6月22日,那个让苏联人民刻骨铭心的血色黎明!
      这天凌晨,以大规模空袭为序幕,550万德军在2000公里长的战线上,以不宣而战的方式向苏联发起全面进攻,苏联卫国战争爆发!战争伊 始,4980架德军飞机,就以疾风暴雨之势,席卷了苏联西部国境线上全部66个军用机场。德国人对作战时机的把握异常精妙——1941年,苏军正进行历史 上规模最为庞大的一次装备更新。为了确保部队换装的顺利进行,苏军把原本分散在各个野战机场的作战飞机,都集中到了少数几个大型机场上,这就使得德军可以 集中兵力进行重点攻击。在德军密集空袭下,仅6月22日一天,苏军就损失1200架作战飞机!
      面对已取得绝对制空权的敌人,苏军战机仍义无反顾地起飞迎敌!德国空军很快就为这场战争付出了代价——一架米格-3战斗机在德军的空袭中强行起飞,英勇的苏联飞行员在战机被击中起火后并没有跳伞,而是径直撞向了一架德军的He-111轰炸机!这是苏联空军
      在卫国战争中取得的第一个战果,并以此为序幕,拉开了苏联军队延续半个多世纪的“撞击作战”的惨烈长卷!
      仅6月22日一天,苏军飞行员就进行了17次空中撞击!促使苏军飞行员采用这种战法的原因,除了个人英勇之外,更多的却是一种令人心碎的无 奈——已经装备部队的米格-3等新型歼击机原本就数量不足,而且大部分已在德军第一波攻击中遭到摧毁,这就使得老式的E-153和E-16战机成为抗击德 军的主力。和德国空军装备的Bf-109新型歼击机相比,这两种老式战机无论在速度、火力还是机动性上均处于下风,在正面对抗取胜无望的情况下,苏军飞行 员们最终选择了“空中撞击”这种玉石俱焚的惨烈方式,来履行自己捍卫祖国领空的神圣职责!
      随着战火向苏联腹地逐步蔓延,苏军飞行员进行的空中撞击作战的次数也迅速增加!在撞击作战的飞行员名单中,甚至出现了女飞行员的名字—— 1941年9月12日,苏联空军第135轰炸机团的女飞行员叶卡特琳娜•泽连科上尉,奉命前往攻击进犯基辅附近罗内姆地区的德军古德里安第2装甲集团,战 斗中,泽连科上尉驾驶的苏-2轰炸机遭到德国空军第51战斗机联队7架Bf-109的围攻并被重创,年轻的女飞行员放弃了跳伞求生的机会,毅然撞向一架 Bf-109,与之同归于尽。
      苏联国土防空军,甚至将空中撞击列为了对抗德军轰炸机的常规作战手段之一,在战机弹药耗尽后,苏军飞行员往往会有意识地利用敌轰炸机后方的 射击死角靠近敌机,再使用螺旋桨撞击敌机尾翼,以使敌机失去平衡坠地。令人稍感宽慰的是,和那种以命搏命的正面撞击相比,采用这种战术的苏军飞行员的生还 几率会大为增加。
      1941年9月14日,苏联国土防空军第787歼击航空兵团飞行员鲍利斯•皮罗日科夫少尉,驾驶一架米格-3歼击机,在莫斯科以南的空域, 连续2次空中撞击1架德国空军的Do-217型轰炸机。皮罗日科夫,也由此成为第一位在一次空战连续2次撞击敌机并最终将敌机撞毁的飞行员。1942年9 月4日进行的保卫莫斯科的空战中,已晋升为上尉的皮罗日科夫,再次以撞击敌机尾部的方式.将1架He-111型轰炸机击落。撞击中皮罗日科夫身负重伤,但 仍以惊人的毅力将战机飞回了机场。尽管医生用了9个小时的时间来挽救英雄的生命,但皮罗日科夫上尉还是在手术台上停止了呼吸。
      整个卫国战争中,苏联空军、国土防空军和海军航空兵。先后有404名歼击机飞行员、18个强击机空勤组和6个轰炸机空勤组,进行了空中撞击。其中有17名飞行员曾进行2次空中撞击。苏联英雄鲍里斯•伊万诺维奇•科夫赞,更是创下了先后4次进行空中撞击的惊人纪录。
      除了频繁的空中撞击外,苏军还把“撞击战法”应用到了地面和水面作战中,苏联卫国战争是人类战争史上第一次真正意义上的机械化战争,苏德双方均在战场上投入了大量的坦克和自行火炮,这就为实施坦克撞击创造了客观条件。战争之初,在西南方向的杜布诺—罗
      夫诺坦克会战中,苏军骑兵第14师下辖的坦克第29团排长克拉韦茨少尉,就在击毁敌2辆坦克且自己的座车受重创后,实施了坦克撞击,与敌同 归于尽。苏军“坦克拼刺刀”的战法,在库尔斯克会战中达到极致。会战中,德军首次使用了“虎”-1、“黑豹”等新型坦克,面对这些防护力明显提升的对手, 苏军的T-34-76型坦克装备的76毫米主炮,已难以在正常交战距离上击穿其正面装甲,这就促使苏军更多的采用近战甚至直接撞击的战法,来消灭敌人的坦 克。卫国战争中,苏军共进行了约100次坦克撞击。
      同样的撞击战例,也出现在苏联海军战史上。1944年6月13日夜,正在楚德湖北部巡逻的苏联海军312号和322号装甲艇,与4艘德军炮 艇发生遭遇战。战斗一打响,4艘德军炮艇立刻散成扇形,围攻苏军编队前方的322号艇。紧急关头,后面的312号艇艇长斯米尔诺夫,指挥全速撞向一艘德军 炮艇并将其拦腰撞为2截!1944年12月8日夜,苏联海军北方舰队的“不沉”号驱逐舰,又以冲撞的方式将德国海军U-387潜艇击沉。卫国战争中,苏联 海军在海上共撞沉了14艘纳粹德国的舰艇。
      刀锋拭血冷战岁月
      二战结束了,战争的阴霾却并没远去,以1946年3月5日英国前首相丘吉尔在美国密苏里州富尔顿发表的“铁幕演说”为标志,反法西斯同盟正式瓦解,曾经的战友顷刻变成了枕戈待旦的对手,一场持续了近半个世纪的冷战由此拉开了帷幕。
      尽管对核战争的共同恐惧,让冷战的双方都有意识避免可能诱发新的世界大战的全面对抗,但彼此间的试探甚至挑衅却从未停止。此间的一系列交锋中,再次让人们看到了——撞击!
      1973年11月28日,1架美国T-38型教练机侵入苏联领空,苏联巴库防空区紧急起飞一架米格-21拦截,在飞行员叶利谢耶夫发射了2 枚空空导弹都被T-38机动规避后,苏军地面指挥部向米格-21下达了撞击指令,叶利谢耶夫随即驾机向T-38径直撞去,双方同归于尽!战斗结束后,苏联 政府正式追授叶利谢耶夫“苏联英雄”称号。在8年以后的1981年7月,苏军库利亚平大尉,又驾机用对撞的方法,击落侵入外高加索地区的美国CL-44
      飞机,值得一提的是,在双方对撞的前一刻,库利亚平大尉成功跳伞,死里逃生。
      和苏联空军的偶一为之相比,苏联海军对于撞击作战,除了继承之外还做了进一步发扬,撞击的战场也由单纯的海面撞击延伸到了水下。1988年 2月12日,美国巡洋舰“约克城”号和驱逐舰“卡伦”号,借口“维护无害通过权”而进入苏联军港塞瓦斯托波尔以南7海里的水域,两舰立即遭到苏联海军“克 里瓦克”级护卫舰“无私”号和“米尔卡”号的严密
      监视和驱赶。在多次警告无效后,“米尔卡”号向美舰发出了“我舰奉命撞击你舰”的信号,随即以舰艏向“约克城”的艉部发起主动冲撞,撞坏了“约克城”号巡洋舰的艉部,而“米尔卡”号护卫舰舰艏水线以上部分也严重受损。
      和海面上的冲突相比,水下冲突显得更为直接与残酷!在黑沉寂静、诡异难测的波涛下,双方的核潜艇屡屡上演类似“猫捉老鼠”的跟踪与反跟踪的 水下较量。频繁交锋中,双方各自发展出一套针对敌方潜艇的对抗战术。西方潜艇的标准战术动作是,想尽办法绕到对方后面,而苏联艇长通常摆舵旋回,并采取迎 头对撞的战术动作。美国和英国把采取这种玩命方式来摆脱跟踪的俄国潜艇,叫“疯狂的伊万”,他们最怵头的就是苏联艇长的这一手。由于苏联核潜艇的主要基地 都在北极圈附近,所以在设计上非常强调结构坚固,加之双壳体小分舱结构,故一旦发生水下撞击,吃亏多是西方潜艇。
      这种潜艇对撞的游戏,在苏联解体3个月后成为现实。1992年2月11日,美国海军洛杉矶级攻击核潜艇“巴吞鲁日”(SSN-689)号, 在俄罗斯科拉半岛军港入口处跟踪到俄北方舰队的“塞拉”I型攻击核潜艇K-276号。察觉到美国核潜艇的动作后,K-276立即摆舵旋回,向“巴吞鲁日” 号迎头撞去——标准的“疯狂伊万”!尽管“巴吞鲁日”号做出了闪避动作,但其艇身还是被K-276的指挥台围壳直接撞中,撞击的结果是——“巴吞鲁日”号 的耐压艇体上留下了不可修复的严重损伤,该艇因此不得不在3年后退役,成为了第一艘退役的洛杉矶级潜艇。而K-276号艇,尽管指挥台围壳全毁,但耐压壳 体却没有遭受太大的损害,在修复后重返北方舰队,并服役至今。这是迄今为止俄罗斯军队最近的一次撞击作战,但未必是最后一次!
      无畏士兵成就无敌军队
      世界战争史上,进行过撞击作战的军队并非只有苏/俄军队,除了臭名昭著的旧日本海军“神风特攻”之外,纳粹德国空军也曾在二战末期组织过空中自杀性撞击作战。但若要论持续时间之长,参与军种之多,日德军队在苏联军队面前只能相形见绌。
      如果说卫国战争初期,苏军飞行员不顾危险迎头撞击敌人,是一种反抗精神的体现,不得已而为之,无奈,悲壮。那么到后来越来越多的撞击,更多 的则是作为一种战术出现的。从海军潜艇迎头撞击到苏-27战机威慑性的手术刀事件,撞击已发展为一种有效的警告战术。冷战中,这种战术表现出相当的合理 性:撞击事件对于双方都有损失的,因此在对峙的军事行动中,可以被双方所默认而不会引起大规模的军事冲突。在撞击中,苏式武器还表现出一种另类的优势。苏 -27的部分尾翼受损无碍飞行,潜艇指挥台围壳全毁而耐压壳无恙,这种优势让他们撞起来更加有底气。
      但这种深具中世纪传统的战术,反映的更深层次的东西是什么呢?是苏式武器装备的坚固?抑或是艺高人胆大的炫耀?不,是勇气!是士兵的精神! 这在苏/俄军队中,一直被广为重视和不断发扬。无畏的士兵也造就了无敌的军队.人们不妨从俄罗斯这个民族的身上,去探寻勇气背后的精神基因。
      地处极北苦寒之地的俄罗斯,自然环境的艰苦曾铸就了坚韧的民族性。一方面,这个自15世纪末便以“第三罗马”自居的东欧民族,对以英德法为 代表的西欧文明一直抱有艳羡甚至觊觎的复杂情感,而另一方面,这个“欧洲国家”的血脉里,流淌的更多的鲜明的亚洲基因。作为昔日蒙古帝国的臣属,俄罗斯的 崛起之路,其实就是一部由抵抗他人征服到征服他人抵抗的征伐史。时至今日,人们仍可在俄罗斯的政治文化、军事思想等方面寻找到昔日金帐汗国的烙印。
      和更强调个人的西欧文明相比,更加东方化的俄罗斯带有鲜明的集体主义色彩。俄罗斯军队秉承了蒙古军团的坚韧及悍不畏死的作风。因此,在苏/俄军队的战史中,出现如此众多的撞击战例,粗看似乎出人意料,但追根溯源,却又在情理之中!

EXCEL,将A列中相同代码所对应B列的数值进行自动求平均

March 31, 2014
C1输入=IF(COUNTIF(A$1:A1,A1)=1,AVERAGE(IF(A$1:A$100=A1,B$1:B$100)),””)数组公式,输入后先不要回车,按Ctrl+Shift+Enter结束计算,再向下填充。