Intelligence Failures and Escape to Tibet : 1971 India-Pakistan War

Failures of intelligence contributed in large part to the surrender of Pakistan's Military in Dec 1971 Indo-Pakistan War. From the chronology of the events, it would seem that there was an acute shortage of "strategic intelligence". Strategic intelligence would only focus on the bigger picture, the overall scenario. Intelligence failed in providing the high command with the real intentions of India, the imminence of a war and whether the decisive battles would be fought in the east or the west. The importance of strategic intelligence can be judged from the fact that force deployments are done based on it.

Here, however, we would consider a case of tactical intelligence failure (with strategic consequences in this case).   

Pakistan-Iran Petroleum Pipeline

A few thoughts on the Pakistan-Iran Gas Pipline.

During the previous years, there was talk of Iran-Pakistan Gas Pipeline. Several articles appeared in the national press regarding the impracticality and unfeasiblity of this project. I do not agree with such opinions and would try to explain the need for such a pipeline.

First of all, I was amazed to know that this gigantic project is only meant to transport natural gas to Pakistan from Iran. What about liquid petroleum products like diesel, petrol and kerosene? Tanks, aeroplanes, helicopters, trucks, vehicles, ships, submarines etc need diesel, petrol and kerosene. They do not run on gas.

Fuel is part of the military logistics and it directly affects the war waging or defence capability of a country. Its importance can be judged from many historical examples. Before the Normady Landings during Second World War (1939-1945), Allies had established oil pipelines across the English Channel to transport petroleum from UK to main Europe (France). This gigantic work was called Operation Pluto (Piplelines Under the Ocean).

Theoretical and Experimental Science

From the reactions of readers, I feel that first of all I need to explain what experimental approach in science means. Some people start imagining it in the same light as doing medical experiments on mice, pigs or monkeys. Its not about that. Here by the experimental approach I mean practical or hands-on approach using tools, equipment, machinery etc (more of applied science).

Industrial application of science or say technology has never waited for a perfect scientific theory to explain its working. When the automobiles were made, it was thought that electricity flows from the positive terminal to the negative and all electrical wiring was designed with this wrong theory but it worked and till now the same wiring is being used. Now we know that electricity always flows from negative to positive terminal.

Transfer of Technology (ToT)

Armed forces need to induct new weapon systems from time to time to keep up with the latest technology. Similarly, the civilian industry like railways etc need upgradation of its infrastructure to remain profitable or at least remain operational.

Sometimes, Transfer of Technology agreements are signed for the local production of civil engineering equipment or defence equipment.  ToTs done till now did not help us become self-sufficient because they were strictly production ToTs (not including design details).

ToT is not only the drawings of individual components or their assemblies, types of materials or alloys used, heat treatment and surface treatment details, quality certification criteria and manufacturing techniques.  Real ToT items are the details of engineering calculations for the design of individual elements. For example, we can study a case of ToT for an aircraft or a missile system (defence equipment) and some design details that are needed for such a project:

Modern Close Combat Air-to-Air Missiles in The South Asia

At first I intended to write on the balance of air power in the South Asia but feeling later that it would need a much detailed article, I switched to the topic of air to air missiles (AAMs) and restricted to India and Pakistan. Additionally AAMs carried by combat helicopters are not included here.

Air superiority over the battlefield or over a theater of war is primarily established through fighter aircrafts using air to air missiles and associated sensors and systems. Ground-based air defence systems on the other hand are designed to deny the use of airspace to the opponent. They can't establish air superiority by themselves.

What many people do not realize is that Indian Air Force today has more variety of air to air missiles than any other country on the planet. The Surface to Air missiles (SAMs) types are also varied. These missiles have been purchased from Russia, Israel, France and United Kingdom. The indigenous air to air missile program is an additional category. Variety poses its own problems for a defender. The onboard jammers (called self-protection jammers) carried by fighter jets give best results if optimised against certain threat types.

Autopilot for Crashing the Aircraft

Aircraft defections were a common occurrence of the early Cold War era (1950-65). USA and USSR used their spies and agents to get their hands on the latest military jets of each other. Defections were easily done in the aircrafts of 1950s and 1960s because there were no on-board flight control computers, no softwares and no digital autopilots (mechanical and analog electronic autopilots did exist).  These fighter jets include Mikoyan Mig-15, Mig-17, Mig-19, early Mig-21s, Sukhoi Su-7, North American F-86, Northrop F-5, Hawker Hunter etc. In these early cold war defections, the Air Force or Army high command would have liked to crash the aircraft from ground by activating a crash autopilot or a self-destruction command if such an option was available.

Automobile Maintenance: Engine Cooling System

Cooling system is designed to keep the engine at its optimal operating temperature. It cools down the engine when the optimal temperature is exceeded. Automobile engine is a heat engine and apparently it is a waste of energy to remove heat from an engine but it is due to the reliability requirements and metallurgical properties of the metals used in the engine construction that excessive heat has to be removed.

Engine Performance

Engine performance is directly linked to the cooling system. Engine uses a rich mixture when the engine (or coolant) is relatively cool and then moves to lean the mixture as engine heats up. If an engine is overheating, the ECU or PCM would reduce the ignition advance and/or fuel injection pulse duration, both leading to a loss of power. Engine temperature is measured indirectly through the coolant temperature.

Choice of Coolant

A coolant is also known as anti-freeze in everyday parlance but it gives an incomplete picture of its functions. A coolant should not freeze in winter when temperatures are below zero degree Celsius but it should also have a higher boiling point (at least higher than water, which is 100°C at sea level). Additionally, it should have a low vapor pressure, high specific heat capacity, high enthalpy of vaporization and very low electrical conductivity.  Pure water has a high specific heat capacity but has a high vapor pressure (unsuitable), a lower boiling point (unsuitable), high freezing point (unsuitable) and unsuitable electrical conductivity. Therefore, water is mixed with other chemical coolants like glycols to produce an acceptable mixture. Water can be used temporarily though, in case the engine develops a coolant leak on the road and you need to top up the coolant.  In Pakistan (1990s), it was common to see truck drivers (very rugged Bedford trucks) pouring fresh water into hot radiators on the road side. Not only water is not a good candidate as a coolant (except in some races) but cold water should not be poured into a hot engine.

Organizing Scientific Research

Scientific research has to be well-organised and well-coordinated to yield results. Research can be organized using different schemes or criteria. Organization helps to complete projects in time and avoid duplication of efforts. Some of these schemes of organization are given here.

1- By Approach

Scientific research or study can be carried out in three main modes. These are experimental (measurements using equipment), computational (doing simulations) and analytical (or theoretical). This type or form of research needs to be developped in Pakistan (or even in South Asia as a whole). Institutes specialised in experimental sciences are the ones that put any proposal to the test and then the realization of prototypes based on the results. Such institutes are operational in the USA, Europe and other scientifically advanced countries. For example, Center for Turbulence Research (CTR) in USA and CERFACS in France are dedicated centers for Computational Fluid Dynamics. Similarly Von Karman Institute (VKI) of Fluid Dynamics in Belgium specialises in the experimental approach in aeronautics.

Nuclear-Capable Missiles of The South Asia

Whenever there is a surface-to-surface missile test in the South Asia (India and Pakistan), the news reports read, "Nuclear capable missile has been test fired". Some links are given here;

India tests nuclear capable missile with range as far as Beijing,
http://www.reuters.com/article/2013/09/15/us-india-missile-idUSBRE98E03L20130915
India Tests Nuclear-Capable Missile,
http://www.wsj.com/articles/india-tests-nuclear-capable-missile-1422719598

Few countries around the world openly possess nuclear weapons and they know well their working. These countries are USA, Russia, France, UK and China. The ballistic and cruise missiles with nuclear warheads that these countries built were designed from the very start to be armed with nuclear warheads. Accordingly the whole missile system and its launchers were designed to those specifications.

The Natural Boundaries

If we look at the topographic map of the world (superimpose satellite imagery on plain maps), it seems that nature itself has fixed boundaries for various races / civilizations of mankind. Geographical features like rivers, mountains, deserts and straits often form the "natural boundaries" among these races or civilizations. These natural boundaries can both be international or within the country e.g., Punjab (Pakistan) is defined by its five rivers, Valley of Swat (Pakistan) is defined by its mountains and part of Indus river has remained a boundary between Punjab and Khyer Pukhtoonkhwa (Pakistan) for a very long time.

History shows us that conflicts arise whenever man tries to change these natural boundaries. Here are some of the natural boundaries that I picked up. Do add your own observations about natural boundaries around the world. 

My Engineering Research And Publications

My area of research during PhD studies was Turbulent Boundary Layer Flows of Newtonian Fluids, which itself is a sub-branch of the Fluid Dynamics or Aerodynamics. Fluid dynamics deals with the flow of any fluid (air, water or another liquid, a gas, molten metals etc) around or inside an object of interest. Aerodynamics deals only with the flow of air around or inside an object of interest.

A fluid flow can be laminar, turbulent or transitional (in between).  In a laminar flow, a physical quantity like velocity or pressure will be the same at a point in space (x,y,z) if measured at multiple instants of time. In a turbulent flow, these physical quantities fluctuate randomly even if measured at the same point at different instants of time.

Almost all of the fluid flows of engineering interest are turbulent (while those of medical interest are mostly laminar like blood flow in a vessel). Furthermore, these flows can be classified as wall-bounded (boundary layers, wall jets, channel and pipe flows etc) and free shear flows (like jets, wakes). Boundary layer is the part of flow very near a solid boundary like the body of a car or frame of an aircraft etc.

Phalcon Meets Its Nemesis (Old Articles Series - 7)

This one is not really an article. I posted this fictional and hypothetical scenario on the Pakistan Defence Forum in 2010. It was a first attempt at writing sensational and fictional stuff. Again no jingoism was meant.  Those who are totally unfamiliar with the military aviation  may find it a bit hard to understand.


Disclaimer: Please note that this is a hypothetical scenario. The names of Minhas, Alam , Khalid and Rafiqui have been chosen for their historical relevance only. All other names and characters have been chosen randomly. Any coincidence would only be by chance.

PHALCON MEETS ITS NEMESIS



Masud: Gentlemen its urgent. We have to send a mission in an hour against IAF Phalcon in the Northern Sector. We have lost element of surprise. All sorties are monitored by Phalcon right from the take-off. During dogfights, Phalcon is acting as a virtual wingman for each Su-30 and these Flankers have enough confidence to operate alone too.

Automobile Maintenance : Rear Drum Brakes

Rear drum brakes are slowly being replaced by rear disc brakes but they still have their own advantages like they don't tend to stick as the disc brakes do. Had to repair my rear brake for the bi-annual vehicle test. Ask the vehicle test operator about the rating of braking power against which your vehicle would be tested because all vehicles don't have the same braking power. In addition, front and rear brakes have very different braking power and test should be in the similar fashion. If your vehicle is tested against a higher rating, your brakes will certainly be damaged and thats what happened to me (brake cylinder damaged!).  

Before starting, put some bricks or chokes around the front wheels so as to prevent vehicle movement during work on the rear wheels. Use a Wheel wrench to loosen the nuts or bolts (European Vehicles).

Automobile Maintenance : Changing the Head Gasket

Apart from the inevitable heating and cooling cycles, Head gaskets start leaking due to many other reasons like engine overheat affecting the gasket itself, cylinder head warpage, inappropirate tighening of the cylinder head, use of inappropirate lubricant for head bolts etc.


You would have to drain all the coolant before starting to disassemble the engine. If the cylinder liners are detachable (not integral to the engine block) then it is preferable to drain the engine oil too, otherwise some coolant may pass through the O-rings of the cylinder liners and go into the oil sump.


To start disassembly, components that are attached to the cylinder head need to be removed. These include intake manifold, exhaust manifold, distributor cap of the ignition system, spark plug wire, timing belt, rocker cover and other accessories if any.

Automobile Maintenance : Alternator Repair and Testing

Alternator is the most important part of the vehicle electrical system. It provides power to run the electrical accessories and charges the battery. Alternator brush change is a common repair for used vehicles. Brushes are mounted inside the brush holder or the voltage regulator of alternator. Recently mounted new brushes in the alternator with related testing partly according to the instructions of Professor youtube and partly my own procedures. Design of the different makes may differ but the principle is same.

First remove the alternator from the engine compartment and remove its voltage regulator. Then remove the brushes by drilling or piercing two holes on the top of the brushes. Voltage Regulator-cum-brush holder with its springs, new brushes and old used brushes. You can see the difference in size.

Automobile Maintenance : Changing the Oil Pressure Switch

If dash warning light of engine oil pressure goes on and off intermittently, it means that either oil pressure switch has gone bad or that oil pressure is actually low. A low oil pressure may mean that either oil pump has gone bad or that engine itself has worn out if the oil level is ok. Most of the times, just changing your oil pressure switch would solve this problem. Here are some snaps of this work done on the 2.2L Petrol engine (Renault J7T)  and designed and manufactured by Francaise de Mécanique.

The Mysterious North

"North always has an aura of mystery around it". It is not amazing that Indian Army troops positioned on the Northern Border of East Pakistan in the 1971 war were the first to enter Dhaka. North has been a privileged direction for the invader and most troublesome for a defender in the history of warfare.

Automobile Maintenance : Changing The Front Shock Absorbers

Had to change my worn-out front shock absorbers (or dampers) for the bi-annual test of vehicle. Worn-out shocks had lowered the vehicle and had also modified the camber angle of tires. Being a purely mechanical job, I decided to do it myself following the instructions of the service manual. This work was performed on the Renault Espace II.

Unmanned Air Vehicles (Old Articles Series-6)

Old Articles Series Part-6. This article was published in a late 2003 issue of the Defence Journal (of Pakistan). Please note that no jingoism was meant, the author wrote it from defence point of view. Author supports peace and cordial relations among countries of the South Asia. Also the information contained should be viewed in the context of the time period in which the article was written or published.

Unmanned Air Vehicles (UAVs)

Columnist Syed Imran Shah makes a thorough study of UAVs

The Need for UAVs

Military commanders have always wanted to observe the movements and deployments of enemy formations. Timely intelligence about the activities of the opponent and situational awareness have always been the key to success. For this purpose, many arrangments were done throughout human history like the construction of observation towers, use of air balloons, manned aircraft of first generation, dedicated reconnaissance aircraft, space satellites and unmanned or uninhabited air vehicles.

UAVs are nowadays used for surveillance and observation, artillery fire direction for naval guns and army batteries, maritime patrol, border patrol, checking illegal immigration and drug smuggling, electronic intelligence, communications relay, search and resuce operations and weather data collection.

Air Defence Of Pakistan Part -II (Old Articles Series - 5)

Old Articles Series Part-5. This article was published in the July 2003 issue of the Defence Journal (of Pakistan). Please note that no jingoism was meant, the author wrote it from defence point of view. Author supports peace and cordial relations among countries of the South Asia. Also the information contained should be viewed in the context of the time period in which the article was written or published.

Air Defence of Pakistan Part 2

The PAF’s defensive capability

SYED IMRAN SHAH

In the recent wars, we can see an identical and regular pattern of air operations starting from the suppression of air defences and attacks by stealth bombers and cruise missiles to the final strikes and bombing. We shall try to analyse these operations.

We shall study both the air defence ground environment and the role of air force.

My previous article on the same topic was more about the ground-based air defence whereas this article is focusing on air defence by air force fighter jets and hence the main theme is air superiority operations. Here the main focus still remains the threat faced by Pakistan due to relentless military build up across its eastern border.

Surface to Surface Missiles (Old Articles Series-4)

Old Articles Series Part-4. This article was published in the May 2003 issue of the Defence Journal (of Pakistan). Please note that no jingoism was meant, the author wrote it from defence point of view. Author supports peace and cordial relations among countries of the South Asia. Also the information contained should be viewed in the context of the time period in which the article was written or published.

SURFACE-TO-SURFACE MISSILES

Columnist IMRAN SHAH details the characteristics.

Introduction

Surface-to-surface missiles have a role of projecting offensive power in the strategic sense. There are two types of surface-to-surface missiles. The first is cruise missiles and other is the ballistic missile. Cruise missile is like an aircraft with wings and a jet propulsion system. Ballistic missile is a missile that does not rely on lift provided by wings and it flies under the action of gravity after the thrust termination. The world’s first cruise missile was V-1 Doodlebug and the first ballistic missile was V-2. Both V-1 and V-2 were made and used by Germany in World War 2. They were relatively inaccurate and were used as terror weapons and had area targets like cities. London was the main target for these new weapons. In WW2, there was no counter to ballistic missiles but British fighters succeeded in intercepting some cruise missiles.

Anti-Ship Missiles: India and Pakistan (Old Articles Series-3)

 Old Articles Series Part-3. This article was published in the February 2003 issue of the Defence Journal (of Pakistan). Please note that no jingoism was meant, the author wrote it from defence point of view. Author supports peace and cordial relations among countries of the South Asia. Also the information contained should be viewed in the context of the time period in which the article was written or published.

Anti-Ship Missiles: India and Pakistan

Columnist Syed Imran Shah discusses the acquirement/development of these missiles in South Asia.

Background

Anti-ship missiles have come to play a pivotal role in deciding the outcome of a naval battle. Let’s take a look at the past. In 1971 war, Pakistan Navy suffered due to SS-N-2 Styx anti-ship missiles. The minesweeper PNS (Pakistan Naval Ship) Muhafiz and PNS Khyber were sunk by Styx anti-ship missiles fired from Missile Boats of Indian Navy.

In 1967, the Egyptian Navy used these Styx missiles to sink the Israeli destroyer Eliat. In the Falklands War in 1982, Argentinean Exocet missiles hit three British ships and in Iran-Iraq war throughout the mid-1980s, Iraqi missiles sank at least five Iranian vessels. In May 1987, two AM-39 Exocets fired from an Iraqi Mirage severely damaged the USS Stark. All these conflicts show the awesome prowess of the modern anti-ship missiles, especially the air-launched ones. The unequivocal demonstration of the Exocet’s effectiveness made it a ubiquitous weapon system. Thus, it has been proved time and again that anti-ship missile is a potent maritime strike weapon. Due to the long-range advantage of the anti-ship missiles, they shall be more instrumental in sinking the ships than torpedoes in a naval war. Club missiles, Kh-35 Uran, Sea Eagle and P-20 are the main anti-ship missiles (AShMs) of Indian Navy. AM-39 and SM-39 Exocets, R/UGM-84 Harpoons, HY-1s and C-802s are the anti-ship missiles of Pakistan Navy.

Counter-Air Operations (Old Articles Series-2)

 Old Articles Series Part-2. This article was published in the December 2002 issue of the Defence Journal (of Pakistan). Please note that no jingoism was meant, the author wrote it from defence point of view. Author supports peace and cordial relations among countries of the South Asia. Also the information contained should be viewed in the context of the time period in which the article was written or published.

Counter-Air Operations

Columnist Syed Imran Shah gives an analysis of future air operations in light of past experience and modernisation of equipment.

Introduction

Counter-air is an air operation of a tactical air command conducted to attain and maintain a desired degree of air superiority by the destruction and neutralization of enemy forces. Both air-offensive and air-defensive actions are involved. But we shall focus on air-offensive actions and counter-air interdictions.

Interdiction is an air-to-ground operation behind the enemy lines to divert, disrupt, delay or destroy the enemy’s surface military potential before it can be used effectively against friendly forces. In modern warfare, it typically refers to the use of air power to destroy bridges, major railway junctions, or other choke points inside enemy territory, thus preventing not only supplies, but also reinforcements from reaching the battle area. Today, interdiction is carried out mostly by Fighter-Bombers of an air force.

Here, we discuss the risks and obstacles involved in interdiction missions, and accordingly the qualities required in the strike aircraft, with special focus on India and Pakistan.

The Air Defence of Pakistan (Old Articles series- 1)

Old articles series Part 1. This article was published in October 2002 issue of the Defence Journal (of Pakistan). Please note that no jingoism was meant, the author wrote it from defence point of view. Author support peace and cordial relations among countries of the South Asia. Also the information contained should be viewed in the context of the time period in which the article was written or published.

The Air Defence of Pakistan

Columnist Syed Imran Shah suggests high-tech modernisation.

INTRODUCTION

The dominant role of air power in modern warfare has been clearly established. A nation unable to defend itself against air assaults of its adversary would be placed at a serious disadvantage in any future conflict. Air defence especially for nations under threat of military aggression thus becomes a vital element in its overall defence strategy.

India has a potent air power strike element that poses a serious threat to the security of Pakistan in any armed conflict. To be able to employ this offensive potential, the Indian Air Force would first have to overcome and degrade Pakistan’s air defence network. A strong and resilient air defence system then becomes imperative for Pakistan in order to prevent the Indian juggernaut. This article will address the air defence issues in general with special focus on Pakistan.

Automobile Maintenance : Brake Caliper Rebuild



If the brakes of your vehicle are sticking to the wheels (infact to the brake rotors), the acceleration of your vehicle would be affected alongwith an increased fuel consumption. Brakes stick when the driver is not pushing on the brake pedal but the wheel is still held by the brake pads. It can be easily found out by jacking up the vehicle and rotating the wheels with hands. If the wheel sticks and is hard to rotate, you need to repair your brake system for that particular wheel. The cause may be sticking slider bolts, stuck caliper piston or jammed flexible brake hose.

Another cause of sticking brakes is the overfilling of the brake fluid reservoir. In my case, a professional workshop had overfilled the brake reservoir and there was no space for the brake fluid to go once the brakes were released. Therefore, do not fill the brake reservoir beyond the maximum mark, or ideally keep the level between the mini and maxi marks.

I am covering all three cases here. Here I am doing it on the front caliper of the Renault Espace with 2.2L  J7T engine. After the necessary diagnostic, if you are replacing your flexible brake hose,  then cut a piece of old hose to be used for pushing out the caliper piston.

Automobile Maintenance : Spark Plug Wires

Spark plug wires are also called Ignition wires or High-Tension leads or Ignition leads etc. These wires carry the high-voltage power from the coil to the individual cylinders of the engine. With Coil-On Plug (COP) Ignition systems becoming the standard, ignition wires have now being reduced to the repair market. If your petrol engine (if it uses ignition wires) is hard to start or misfires during driving , the first thing to check should be the spark plug wires. After visual inspection for cracks etc in the rubber / silicon insulation, do a continuity test with multimeter. The resistance or continuity test would not indicate anything on the state of the insulation of the wires, which needs to be tested separately. One way of doing it has traditionally been starting the engine, looking at the plug wires in the dark and noting any sparks or arcs from wires to the other parts or between wires themselves. Another way to test the wire is with a variable-gap spark tester at various engine rpms. This variable-gap spark tester replaces the spark plug and is attached to the wire. If there is a spark at a wide-gap (at least double the spark plug gap), then wires are ok.  

Electrical Power of Heating Elements : High Resistance or High Current



Many people intuitively think that electric devices with heating elements have a high resistance, i.e., that they get heated due to higher resistance of the conductor element. In the university days, one of our friends from Electrical Engineering (Syed Atif Shah) told us that it was not the case and that devices with higher power rating actually have a low-resistance. The formula for electric power is P = I*I*R where P is for power, I for current and R stands for resistance. Current is squared and therefore it plays the major role. I decided to put this theory to the test and find out for myself. There are many electrical devices lying around and one can easily find out. 

Automobile Maintenance : Valve Job (Cylinder Head)

If the cylinder head has been removed from the engine due to any reason like doing a head gasket job, then it is an ideal time to do a valve job and change valve oil seals.  Valve seals also need to be changed if the engine is burning / consuming oil abnormaly. Valves seal the cylinder during the compression and power strokes. With time, the valve seats get pitted with carbon deposits (especially the exhaust valve seat) and need to be ground (verb grind) to improve sealing for better compression and torque. The valve job shown here was performed on the Renault J7T petrol engine  (designed and manufactured by Francaise de Mécanique).

Automobile Maintenance: Engine Tune-Up - Air Filter, Spark Plugs, Crank Sensor, Idle Air Valve

Note :  This post is not about "tuning", it is about tune-up.  The two should not be confused.

Here I discuss four elements of engine tune-up namely air filter, spark plugs, crank sensor and idle air valve. Of course there are other things like ignition wires that need to be checked or replaced but that would be covered in other posts. 

If you have to replace your air filter, why not replace it with a filter with low-resistance to air flow? Some filters enclose their paper filtering element with perforated metal sheets, which is not ideal for free air flow. A wire gauze air filter is shown below. It offers less resistance to the air flow than a filter with a perforated metal sheet.

Socket Types for Ratchets

In professional workshops or backyard week-end repairs, we need to use sockets with ratchets to install or remove fasteners (bolt or nut).  These sockets come in various sizes and types.

From left to right, the image below shows the three main socket types, i.e., 12-points socket, 6-points socket and a side-grabbing 6-side socket. The 8-points sockets,  used with rectangular nuts, are not so common.   

Steel Bolt Strength Markings

When doing automobile repairs or other machinery maintenance, we often need to install or replace the bolts and nuts. Each bolt is built to a specific standard regarding its tensile strength (the load that it would carry).  People usually do not pay attention to the strength of the bolt when using them. For critical applications, proper strength class bolts need to be used. Both grades (in USA) and classes are used for strength classification. Here we would consider metric system (classes).

Repairing Fastener Threads

It often happens that we  have a fastener (bolt or nut) with damaged threads. Sometimes during installtion, the fastener threads get damaged. If the damage is not serious and  not on the load-bearing threads, then the threads can be repaired and fastener reused. Here is a fastener with partially damaged threads. Here we would only consider right-hand threads.

Automobile Maintenance : Fuel Rail Thermal Insulation

Temperature of the fuel affects both the power and fuel consumption of an automobile. Both fuel injectors and fuel pump are cooled by the passage of fuel through them and if the fuel itself is hot, cooling of injectors would be affected. Colder fuel also gives slightly more power (but a bit higher fuel consumption). Additionally more ignition advance can be used as compared to hotter fuel.  If you are planning on using ethanol fuel, then this procedure is not recommeneded.

As we start the engine, its temperature rises. Gradually, the engine starts to warm up all accessories under the hood. This includes the fuel rail too. If the fuel rail is metallic (which is usually the case), the fuel will  be heated too. Petrol or Gasoline has a much higher evaporation rate as compared to diesel and if there is a leak in the fuel vapour recovery system, fuel vapours would be lost. Also if the fuel tank cap is not tight enough, vapours would leak from the tank at a  rate proportional to the temperature of the fuel. Additionally, if the fuel pump starts to lose pressure, then vapour lock can occur in the fuel system if fuel is hot. If the fuel rail is insulated, fuel can be kept at a lower temperature. Here is an image of Renault J7T (designed and manufactured by Francaise de Mécanique) engine's fuel rail with rail-holding bolts removed.

Note: Thermal insulation of the fuel rail was officially used by Renault for J7T-760 engine of Safrane car. 

Graveyards and Indispensable People

New proverb: "Jet engines can't be made in a country where graveyards are full of indispensable people".

Indispensable or dispensable? Even in the educated circles of Pakistan, the thinking seems to be inclined in favour of "dispensable". The phrase "Graveyards are full of indispensable people" is often used by bosses for certain motives but sometimes it can be detrimental to the intellectual growth of individuals. It is time to scrutinize this phrase.

Great Game of the South Asia

Recently (June 2015) news reports circulated in the media that Indian Armed Forces have launched an operation in Myanmar (formerly Burma) against the insurgents of the North-East India. The insurgency in the North-Eastern India is not a new affair. It is now several decades old. The roots of this problem do not seem to be clear to the younger generation. The origin of this insurgency dates back to the 1800s.

Indigenous Aircrafts with Foreign Engines

Jet engine is a highly technical and complicated machine and is therefore mastered only by technically most advanced countries. It is also evident that aviation is one of the world's most important businesses and it is no surprise that the "business secrets" have been well-guarded. Jet engines are designed and manufactured mainly by USA, Russia, United Kingdom and France. Anyone aspiring to build an indigenous aircraft with gas turbine propulsion system has to buy engines from one of these four countries with some options in Canada. China has been designing and producing aircrafts (military and civil) for several decades but still has not succeeded in designing a reliable jet engine. Chinese fighter aircrafts are mostly equipped with licence-produced or imported Russian engines.

Rail Track Gauge and National Defence

Ever since the steam-powered locomotives have marked the landscape of nineteenth century, railways have remained at the heart of military logistics over land. The design decisions have therefore been influenced by the national defence considerations. One such design element is track gauge or width of the gauge.