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Introduction

INTRODUCTION Cardiac Location and Structures The heart is the driving force of the circulatory system, contracting about 70 times/minute to pump an adequate volume of blood with sufficient pressure to perfuse all body organs and tissues. The muscular organ, about the size of a clenched fist, weights from 300 to 400 g. It is located within the mediastinum of the thoratic cavity, above the diaphragm and between the lungs. This location subjects the hearts activity to influence from all pressure variances during respiration, Fassler, (1991). Intrathoracic pressure varies with the respiratory cycle. On inspiration, the heart moves slightly vertically, and the increased negative pressure generated in the thoracic cavity increases venous blood return to the heart and pulmonary blood flow.

On respiration, the heart moves slightly horizontally as the diaphragm rises, and a decreased negative pressure is generated. The pericardial sac is a fibrous membrane that doubles over onto itself to form two surfaces. A small amount of pericardial fluid in the sac allows the two surfaces to slide over each other without friction as the heart beats. The pericardium performs several functions. First, it provides shock-absorbing protection.

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Second, it acts as a protective barrier against bacterial invasion from the lungs. Third, because of its fibrous nature, it protects the heart from sudden overdistention and increase in size, Fassler, (1991). The heart has three tissue layers: the epicardium (outer layer), the myocardium (middle layer), and the endocardium (inner layer). The epicardium is the thin inner layer of the pericardium. The myocardium, thickest of the three layers, is composed of muscle fibers that contract, creating the pumping effect of cardiac activity.

The endocardium, a smooth, membranous layer that lines all cardiac chambers and valve leaflets, is continuous with the intima, or lining, of the aorta and arteries, Fassler, (1991). The hearts four chambers the right and left atria and left atria and the right and left ventricles are separated by the interatrial and interventricular septa. The atria are thin-walled, low-pressure chambers that serve primarily as reservoirs for blood flow into the ventricles. The ventricles are formed by muscle fibers that contract to eject blood to the pulmonary vasculature (right) and systemic circulation (left). Because the left ventricle must achieve the high pressure needed for systemic circulation, it is much thicker than the right ventricle, (Fig. #1), Fassler, (1991).

The right atrium receives venous blood from the body via the venae cavae. The superior vena cava returns blood from the structures above the diaphragm, and the inferior vena cava drains venous blood from below the diaphragm. The coronary sinus returns venous blood to the right atrium. At the base of the right atrium is the tricuspid valve, which controls blood flow into the right ventricle and prevents back flow to the atrium during ventricular systole. The tight ventricle pumps blood through the pulmonary valve and the branches of the pulmonary artery to the lobes of the lungs, the pulmonary capillaries, and the alveolar capillaries that surround the alveoli, (Fig. #2), Fassler, (1991).

At the alveolar capillaries, gas exchange occurs, that is, blood gives off carbon dioxide and receives oxygen. Then, oxygenated blood returns through the pulmonary veins to the left atrium. The mitral valve at the base of the left atrium controls blood flow to the left ventricle and prevents backflow to the left atrium. Both the mitral and the tricuspid valves are attached to the strong chorae tendineae, fibrous filaments that arise from the papillary muscles of the ventricle Fig. (#1) Location of cardiac structures, Fassler, (1991).

Fig. (#2) Blood flow through the heart, Fassler, (1991). and work to prevent eversion of the valves when the ventricle contracts, The left ventricle pumps blood through the aortic valve into the aorta, (Fig. #3), Fassler, (1991). The basic contractile unit in the myocardium, the sarcomere, is composed of actin and myosin filaments, which are contractile proteins.

The degree to which actin and myosin overlap depends on the length of the sarcomere, which is determined by muscle stretch. Less overlap occurs during diastole, as the ventricle fills and the muscle stretches; more overlap occurs during diastole, when the muscle contracts. Contraction occurs when the action potential stimulates movement of calcium with energy release, causes the filaments to slide past each other and shorten sarcomere, Fassler, (1991). Cardiac Cycle The heart ejects blood during ventricular systole, which comprises approximately one-third of the cardiac cycle. The cardiac muscles relax during diastole, which comprises the remaining two-thirds of the cardiac cycle. The first phase of systole, called isovolumetric contraction, begins with closure of the tricuspid and mitral valves. Pressure in the walls of the ventricles builds in preparation for mechanical contraction.

When ventricular pressure becomes higher than pressure in the aorta and pulmonary artery, the pulmonary and aortic valves open, allowing for paid ejection of blood. Blood is ejected rapidly at first and then more slowly as pressure decreases. Pressure in the ventricles continues to fall until the aortic and pulmonary valves close. Closure of the valves begins the first phase of diastole, called isovolumetric relaxation. During this time, ventricular pressure continues to decrease.

When pressure in the ventricles becomes less than atrial pressure, the tricuspid and mitral valves open, permitting rapid ventricular fillings. The ventricle continues to fill until atrial contraction occurs. Atrial Fig. (#3) Coronary Artery Circulation, Fassler, (1991) contraction contributes the final volume for ventricular filling, Fassler, (1991). Pulmonary Circulation The right side of the cardiac pump, consisting of the right atrium and right ventricle, delivers venous blood to the lungs for oxygenation. The thin-walled pulmonary vessels have little medial muscle and offer six times less resistance than systemic blood vessels.

Since the pulmonary vessels offer little resistance, the right ventricle is considered a low-pressure pump, Fassler, (1991). Systemic Circulation The left side of the cardiac pump, consisting of the left atrium and left ventricle, generates the high pressures necessary to overcome peripheral vascular resistance and to deliver oxygenated arterial blood to all body tissues. Because the left ventricle has a larger muscle mass than the right ventricle, must generate more pressure, and contract with greater strength, it has a greater need for oxygen. Thus, the left ventricle is particularly susceptible to the effects of deficient oxygen supply, Fassler, (1991). Coronary Circulation Coronary artery circulation delivers oxygenated blood to the heart, primarily during diastole.

The small coronary arteries branch off the aorta and encircle the heart at the epicardial layer. The arteries continue to branch and enter the myocardium and endocardium, becoming arterioles and then capillaries. The right coronary artery branches to the right from the aorta and supplies blood to the right atrium, the right ventricle, the sinoatrial (SA) and atrioventricular (AV) nodes of the conduction system, and, in most people, the inferior-posterior wall of the left ventricle. The left coronary artery bifurcates into the left anterior descending and circumflex coronary supplies the left atrium and the left ventricle. In some people, the circumflex artery also provides oxygenated blood to the posterior surfaces of the left atrium and left ventricle, Fassler, (1991). Hemodynamics Cardiac output refers to the volume of blood ejected by the left ventricle into the aorta in 1 minute-normally, about 4 to 6 liters/minute at rest.

Cardiac output is a product of the heart rate multiplied by the stroke volume, the amount of blood ejected from the left ventricle with each beat. The heart rate may vary form second to second or minute to minute. The stroke volume may vary from beat to beat, Fassler, (1991). Heart Rate A change in heart rate can dramatically affect cardiac output. For instance, when the heart rate increases, cardiac output may double or triple. In a person with heart disease, such an increase can be dangerous because it decrease diastolic filling time, increases oxygen demand, and decreases coronary artery perfusion time.

Conversely, if the heart rate falls below 50 beats/minute, cardiac output usually decreases, Fassler, (1991). Stroke Volume Variables influencing the stroke volume include preload, afterload and contractility. Preload is the volume of blood that fills the ventricle at the end of diastole. An increase in diastolic volume increases muscle stretch and subsequent stroke volume. Either excessive or inadequate preload can increase the hearts work load and decrease the stroke volume. Afterload, the resistance to flow from the ventricle, increase secondary to vasoconstriction in the peripheral blood vessels or to increased resistance, such as aortic stenosis.

Increases in afterload result in greater oxygen demand because the heart must use more contractile energy to eject blood. Contractility refers to the ability of cardiac muscle fibers to shorten. Calcium within the cell allows protein fibers to be attracted to each other causing muscle shortening. The contractile (or inotropic) state of the myocardium can be influenced by many factors. For instance, epinephrine, dopamine, and sympathetic nervous system stimulation exert a positive inotropic effect (increase contractility), whereas hypoxemia, acidosis, and such drugs as propranolol (Inderal) exert a negative inotropic effect (decrease contractility), Fassler, (1991). Arterial Blood Pressure The pressure exerted on the arterial wall as blood flows through the arteries is called arterial blood pressure, a product of the cardiac output and the total peripheral resistance, which is determined by blood viscosity and by the length and internal diameter of the vessels. Arteries have a medial or muscle layer in their wall that permits constriction or dilation of the vessel.

Thus, peripheral vascular resistance and blood pressure are affected by vasoconstriction and vasodilation, Fassler, (1991). Cardiac Innervation Innervation of the heart involves the autonomic nervous system and the baroreceptor and Bainbridge reflexes. Autonomic Nervous System The autonomic nervous system influences cardiac activity through sympathetic and parasympathetic verve fibers. Sympathetic fibers are found in the atrial and ventricular walls, the SA and AV nodes. The sympathetic effect on the heart is mediated through beta receptor sites and release of norepinephrine. Stimulation of beta receptors increase heart rate, conduction velocity, and contractility. The major effects are usually on the SA node, increasing heart rate, and the myocardial muscle.

The sympathetic nervous system also has receptor, sites, primarily alpha and beta receptors in peripheral blood vessels. When the sympathetic nervous system is stimulated, the alpha effects predominate in the blood vessels and cause vasoconstriction. The parasympathetic effects on the heart are mediated through release of acetylcholine at nerve endings in the SA node, atrial muscle, and AV node. Parasympathetic or vagal stimulation decrease heart rate and conduction velocity, Fassler, (1991). Baroreceptor and Bainbridge Reflexes The baroreceptor reflex mediates heart rate as well as peripheral vascular resistance.

The baroreceptors-specialized pressure-sensitive tissue located in the aortic arch and carotid sinuses-increase their rate of discharge when they are stretched by increase blood pressure. Impulses are transmitted to the cardiovascular center in the medulla. The cardiovascular center decreases sympathetic stimulation and increases parasympathetic stimulation, thereby decreasing heart rate initiating blood vessel dilation. Conversely, baroreceptors also respond to decreasing blood pressure by increasing heart rate and vasoconstriction, Fassler, (1991). The Bainbridge reflex is thought to be mediated by stretch receptors in the atria.

These receptors may respond to increased volume and cause an increase in heart rate. Contractility is unaffected by the Bainbridge reflex, Fassler, (1991). CORRELATION OF PHYSIOLOGIC EVENTS TO ELECTRICAL EVENTS RECORDED ON THE ECG Through out the cardiac cycle the heart produces a series of action potentials. This sequence of action potential produces a series of deflections that represents different events within the cardiac cycle. The classic series of deflections constituting one cardiac cycle is: P wave, QRS complex, and T wave.

The significance of these deflections (and the intervals between) is explained as follows, (Graph #1), (Fig. #4), Murphy, (1991). P Wave The first wave of the cycle, the P wave, represents the spread of electrical depolarization throughout the atria, Murphy, (1991). PR Interval The PR interval is measured from the beginning of the P wave to the beginning of the QRS complex. It represents the time it takes for the electrical impulse to travel from the atria to the ventricles.

Thus the PR interval has two components: (1) the P wave (time needed to depolarize the atria) and (2) the PR segment (end of P wave to beginning of the QRS complex, representing the time the impulse spends in the AV node), Murphy, (1991). QRS Complex Fig. (#4) Normal cardiac intervals, Murphy, (1991). The QRS complex represents the spread of electrical depolarization throughout ventricular muscle. The QRS complex is composed of several wave outlined in detail below, Murphy, (1991). Q Wave The Q wave is the first negative deflection preceding an R wave (regardless of the size of the deflection).

A Q wave is always downward in direction. This wave usually represents depolarization of the muscular interventricular septum in the frontal leads (I, II, III, aVR, aVL, aVF). Abnormally deep Q waves in these leads are often seen with myocardial infarction, Murphy, (1991). R Wave The R wave is the first positive deflection of the complex. In the frontal leads this wave represents depolarization of the main bulk of ventricular muscle.

An R wave is always directed upward regardless of a preceding Q wave, Murphy, (1991). S Wave The S wave is the negative deflection following an R wave. An S wave usually represents the late depolarization of the last bit of left ventricular muscle. In the anterior precordial leads (V, to V3) the S wave is large because of the normal slightly posteriorly directed mean QRS vector, Murphy, (1991). T Wave T wave represents ventricular repolarization. ST Segment The ST segment is mea …

Introduction

Introduction In this experiment we are trying to find the percentage of water in Barium Chloride Dihydiate. During the experiment you must pay close attention to everything done. We are going to try to stay below a 8 percent error. When timing, make sure you only have the crucible over the bunson burner for 10 minutes, no more, no less. Be aware of how dangerous this chemical can be, so please be careful.

Located below is a list of all the materials you will need to complete this experiment. Please make sure you and you lab partner(s) know how to use this equipment. Equipment / Materials Goggles Bunson Burner Ring Stand Iron Ring Iron Triangle Iron Square Computer Computer Program Scale Chemical (BACL2) Scoop Crucible/Crucible cover Crucible Tongs Matches Safety You must pay close attention to everything at all times. Ladies with their hair not tied back should do so do to the fact that their hair could catch fire while using the bunson burner. Before you start the experiment, take notice to where all the safety equipment is. You must know where the fire extinguisher is, emergency shower/eye wash, and the call for help button.

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Make sure you are wearing your goggles while doing this lab. When washing out the crucible do not turn the water pressure up all the way because the water could splash back into your face. If an emergency does occur, please remain clam and think rationally. Procedure This experiment can be very exciting if you know what you are doing. Before I started the experiment, I set up my lab. I put together my Ring stand and attached the bunson burner up to the gas valve.

Before I light the flame, I asked my partner to turn the two gas valves on while I light the flame with a match. Now that my flame was light, I adjusted the air flowing into the flame. Now I was ready to start with the experiment. When handling the crucible do not touch it with your hands, only use the crucible tongs. My partner cleared the scale and I weighed the crucible with its lid, and it came to 17.09.

I removed the crucible and added the BACL2.2H2O. Placed the crucible and lid back on the scale and got the weight of 18.33. Now it was time to place the crucible over the bunson burner. I carefully placed the lid on the crucible and carry the crucible over to the bunson burner and placed it on the iron triangle and. And placed the crucible directly over the flame and set a timer to 10 minutes. While I was waiting for the experiment to finish, my partner decided that she wanted to start another experiment.

So we prepared the scale and crucible and re-weighed everything. By the time we had finished, the alarm sounded and we quickly took the crucible off the flame. We left the crucible cool for another 10 minutes and then re-weight it and it came to 18.15. Christy started to put all the weights in the computer and to our big surprise we got a 0.23 experimental error and a 1.59 percent error. We were so glad that the experiment went to well that we let it get to our head.

We thought we would do even better on our next experiments, but we were wrong. Our percentages started to raise and we realized that we were not doing something right. We noticed that we were not watching the clock and completely messed up the experiment. Percent of water in Barium Chloride Dihydrate Experiment Mass of Crucible and Cover——————————————— ————-17.09 Mass of Crucible, Cover and BACL2.2H2O————————————– 18.33 Mass of Crystallized BACL2.2H2O—————————————- ——– 1.24 Mass of Crucible and Cover——————————————— ————- 17.09 Mass of Crucible, Cover and Anhydrous BACL2 —————————— –18.15 Mass of Anhydrous BACL2——————————————— ———— 1.06 Mass of Crucible, Cover and BACL2.2H2O————————————— 18.33 Mass of Crucible, cover and Anhydrous BACL2——————————— 18.15 Mass of water lost by heating——————————————- —————-.18 Percent water in Crystallized BACL2.2H2O—————————————1 4.52 Theoretical Percent of H2O in BACL2.2H2O————————————14.7 5 Mass of Crystallized BACL2.2H2O—————————————- ———1.24 Mass of Anhydrous BACL2 ————————————————– ——1.06 Mass of water lost by heating——————————————- —————.18 Experimental Error——————————————— ————————–.23 Percent Error——————————————— ——————————-1.59 Error Most of my error was caused by the fact of the flame not staying still in one spot. The ventilator on the ceiling was blowing air down onto the flame and caused the flame to flicker.

Conclusion This experiment was very interesting and informative. We learned the value of paying attention to what we are doing and to not let our mines wonder.

Introduction

INTRODUCTION This report will strive to clearly discern the differences between the average home Video Cassette Recorder (VCR) and the recently developed Digital Video Disc (DVD) system. These two home entertainment components have very clear differences. It is important for consumers to carefully consider each of these concerns before deciding on the home entertainment component that is right for them. When considering the purchase of a home VCR or DVD system, consumers should carefully examine the varying costs of the two components. If cost is a concern, consumers should pay special attention to the purchase price of both systems, as well as the cost of movies and maintenance.

A second consideration of consumers when choosing between VCR and DVD should be the video and audio quality. Various technical factors can alter the quality of both picture and sound in both of these systems, making picture and audio quality a major consideration when shopping for home entertainment components. A final consideration that consumers should give special attention is the accessibility of the systems. In todays growing entertainment market, the difficulty in accessing video and DVD movies can play a large part in the decision of which component is right for the consumer. METHODS The beginning of any research project is in the decision of a topic to research.

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I chose to research the differences between the VCR and DVD home entertainment systems because the intricacies of the systems and the ways in which they work greatly interest me. I began my work using ordinary encyclopedias, found in the Rosewood High School branch of the Wayne County Public Library. Due to the technical nature of my topics, there was very little information in the encyclopedias dealing with these topics. While I did receive some information on the background of home entertainment systems, especially the VCR, most of my research had to be found from other sources. I continued my research into the differences between these two systems, using the Microsoft Encarta Multimedia Encyclopedia. Through this source, I discovered a great deal of information on how the VCR works.

However, little information was to be found on the DVD home entertainment system. For this information, I was forced to search the Internet, where a wealth of information exists. After a general search for DVD, I found several web sights discussing the pros and cons of DVD, as well as the intricacies of how it operates. After making notes of all of the information I had gathered, I proceeded to sort the notes into separate groups dealing with the VCR and DVD. This made it much easier to group my notes into feasible arguments for and against each system, as well as easing the process of making a final decision on the value of each system. At this point in the process, it was necessary to draw my final conclusions, and begin work on the composition of the paper.

After completing this phase of the process, all that will be left is to prepare for the presentation of my information and conclusions. RESULTS/DISCUSSION Today, there are two main options of video components in a home entertainment system. The Video Cassette Recorder (VCR) and the Digital Video Disc (DVD) player are both positive additions to any home entertainment system. Both systems offer benefits and disadvantages to their users, and both should be carefully examined before a final decision is made on which one a consumer should purchase. The VCR was first developed in the 1950s, but did not become a part of the average home entertainment system until the 1980s, when the machines became much more affordable for the average household. The VCR uses ordinary video cassettes, measuring approximately four inches by seven inches, containing yards of video tape inside.

This video tape is little more than a plastic strip covered with particles of iron oxide. This strip is recorded on by changing the television signals used to broadcast programs into magnetic fields, which magnetize the particles of iron oxide into patterns. The tape is played back by converting the magnetic patterns on the tape back into television signals. Many VCRs today use a form of recording and playback known as helical scan. In helical scan, one or two record/playback heads are mounted on the circumference of a drum that rotates rapidly in the same direction as the tape moves.

Through this process the video tape is rolled off of one reel in the cassette, through the heads of the VCR where it is converted to picture form, and back onto the opposite reel of the video cassette. The Digital Video Disc (DVD) player was recently developed, and has undergone some major advancement through the use of rapidly advancing technology. Unlike the VCR, DVD uses a circular disc, similar in appearance to music CDs. On this disc, or DVD, original video signals are encoded by the manufacturer as minute elliptical depressions in the surface of the disk. This information is arranged in a single long spiral, like the groove of a record. To play back the images, the track is scanned by a very narrow laser beam inside the DVD player.

Light from this laser beam is modified by the elliptical depressions, and is then converted back into the original patterns of electrical signals. These signals are then fed by cable into a standard television, where they are converted to a picture. VCRs offer many advantages to consumers looking for a reliable source of home entertainment. One of the most appealing characteristics of a VCR is the machines ability to record television programs for later viewing. This offers consumers the option of viewing programs that aired while they were away from home, or while watching a second program on a different channel. This is a characteristic not readily available on the DVD system.

VCRs also offer easy accessibility for consumers, as materials for viewing on the machine are easily attainable in most communities. Blank video tapes used for recording are sold in most major department stores, as well as grocery stores and even service stations. In addition, movie studios have chosen the video cassette as their main mode of transferring their product to the public. Therefore, pre-recorded video cassettes are readily available for purchase in many stores across America. Finally, one of the largest markets in the entertainment business today is the video rental business.

Such stores as Block Buster Video and A-1 Video have made thousands of m …

Introduction

June 6, 1944 will be remembered for many reasons. Some may think of it as a
success and some as a failure. The pages following this could be used to prove either one.
The only sure thing that I can tell you about D-Day is this: D-Day, June 6, 1944 was the
focal point of the greatest and most planned out invasion of all time.
The allied invasion of France was long awaited and tactfully thought out. For
months the allied forces of millions trained in Britain waiting for the Supreme Commander
of the Allied Expeditionary Forces, General Eisenhower to set a date. June 6, 1944 was to
be the day with the H-hour at 06:30. Aircraft bombed German installations and helped
prepare the ground attack. The ground forces landed and made their push inland. Soon
Operation Overlord was in full affect as the allied forces pushed the Germans back towards
the Russian forces coming in from the east. D-Day was the beginning and the key to the
fight to take back Europe.


Preparations for D-Day
Operation Overlord was in no way a last minute operation thrown together. When
the plan was finalized in the spring of 1944 the world started work on preparing the
hundreds of thousands of men for the greatest battle in history.
By June of 1944 the landing forces were training hard, awaiting D-Day. 1,700,000
British, 1,500,000 Americans, 175,000 from Dominions (mostly Canada), and another
44,000 from other countries were going to take part.
Not only did men have to be recruited and trained but also equipment had to be
built to transport and fight with the soldiers. 1,300 warships, 1,600 merchant ships, 4,000
landing craft and 13,000 aircraft including bombers, fighters and gliders were built. Also
several new types of tanks and armoured vehicles were built. Two examples would be the
Sherman Crab flail tank and the Churchill Crocodile.
On the ground Britain assembled three armoured divisions, eight infantry divisions,
two airborne divisions and ten independent fighting brigades. The United States had six
armoured divisions, thirteen infantry and two airborne divisions. With one armoured
division and two infantry divisions Canada also contributed greatly with the war effort
especially when you look at the size of the country at the time. In the air Britains one
hundred RAF squadrons (1,200 aircraft) paled in comparison to the one hundred and
sixty-five USAAF squadrons (2,000 aircraft).
The entire Operation Overlord was supposed to go according to Montgomerys
Master Plan which was created by General Sir Bernard L. Montgomery. His plan was
initiated by a command system which connected the U.S. and Britain and helped them
jointly run the operation. His plan was to have five divisions act as a first wave land on the
sixty-one mile long beach front. Four more divisions as well as some airborne landings
would support the first wave. The beaches of Normandy would be separated into five
beaches, codenamed, from west to east Utah, Omaha, Gold, Juno and Sword. The
Americans would invade the two westernmost beaches, being Utah and Omaha and the
British and its Dominions would take Gold, Juno and Sword. The Canadians were nearly
the entire force to land on Juno beach. The operation was also coordinated with various
French resistance groups called the Secret Army.

The naval plans were to transport the allied expeditionary forces, help secure and
defend a beachhead, and to help setup a method of constant resupplying of allied forces.
Operation Overlord, in short, was as follows: The airforce would be used to knock
out German defences and immobilize their forces, blowup tanks and other dummies were
used to fool Germans into thinking the invasion was coming at Pas de Calais, the navy
would transport the troops while doing whatever it can to help them gain ground, and
enough of France would be liberated and held by allied forces so that they would not be
pushed back into the sea.



Utah Beach
Utah beach was a stretch of beachfront approximately five miles long and located in
the dunes of Varreville. Like most beach attacks that day, the planned attack time was
06:30 or H hour. As early as 02:00 (H-4:30) the preparations for attack were being made
as minesweepers started working at creating a safe path for allied battleships, frigates,
corvettes, etc. At about 02:30 the flagship for Utah beach was in place and the order was
given for the landing crafts to be loaded and placed into the water. The four waves of
troops were ready to go and the German radar had not spotted any buildup of ships.
The first gunfire occurred at daybreak when some ships were spotted and fired
upon by coastal guns. 276 planes, all B-26 Marauders flew in to drop their payload of
4400 bombs on the targets. Almost all missed and nearly a third fell onto the beaches and
into the sea, far away from their targets. Although some guns were silenced the poor
accuracy of the aircraft was costly and would turn out to be only one of the many errors
made by the allied forces.
At 06:30 the first of the troops landed, the 8th and 4th infantry missed the correct
beach and landed 2,000 yards away on what turned out to be a less heavily defended beach.
This mix up was blamed on smoke and rough seas. These first troops were all part of the
twenty landing craft, each carrying thirty men that made up the first wave. After the first
wave came the 32 amphibious tanks. The second wave of troops consisted of 32 craft
carrying combat engineers and a naval demolition team. Dozer tanks would make up the
third wave. Long after the securing of the beach 2 engineer battalions arrived.
This may sound like all the divisions made it easily to shore but that is not true.
Many amphibious tanks were unable to make the trek on the rough seas and sank. Two
out of the three control vessels for the beach hit land mines and sank and countless landing
craft were shelled by German coastal guns. There were also several drownings involving
troops being weighed down by their equipment and drowning in water around six feet
deep.
If the soldiers managed to make it to shore they were still faced with German
machine gun fire. Fortunately, the beach and its surroundings had become the victim of a
large sea launched missile attack clearing most of the German defences.
Once divisions had made it on the beach and secured it they had to start moving
inland on their pre-planned missions. The divisions that landed on the wrong beach
decided to start the war from right here. Most of the landed troops were supposed to
secure the areas and push inland, eventually meeting up with the 82nd and 101st airborne
divisions that had dropped behind the enemy in order to cut them off from escape and so
that they could be attacked from two angles.
In the Utah Beach attack there were six divisions involved. The 4th and 8th
divisions that landed on the wrong beaches still continued on with their missions. The 4th,
which was originally supposed to land on the islands of St. Marcouf to destroy coastal guns
thought to be there ended up moving inland and linking up with the 101st airborne
division. The other division that landed in the wrong location was the 8th. Their mission
was to reduce beach fortifications and to move inland. The last two divisions were the 12th
and 22nd. Both divisions were to work together to secure the Northern region of the beach.
The 22nd was to move northwest clearing beaches and the high ground overlooking them
while the 12th moved inland on their left flank. Unfortunately the 22nd was unable to
make its deep swing into the Northwest.
By the end of the day the only infantry that was able to make it to its D-Day
objective was the 8th infantry that had landed on the wrong beach. Most of the area was
secure except for a pocket of Germans that controlled a small area shaped like a two mile
finger on the ridges north of Les Forges. The experimental idea of having two airborne
divisions drop farther inland had helped make the Utah Beach attack a near success.

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Omaha Beach
The Omaha beach area was the largest of all the Normandy beaches at
approximately 34,500 yards in length. The beach itself had only five passable ways off,
creating another difficulty for the landing troops and vehicles. Behind the beach were
heavily defended bluffs and high cliffs.
In order to invade the area, with its twelve German strongpoints over 34,000 troops
and 3,300 vehicles would be involved in the Omaha Beach invasion. The large number was
partly because of the fact that beginning in April of the same year German military had
started to fortify the area in hopes of deterring any invasion from the area. The sandy
beaches themselves were free of mines but three bands of obstacles were put into place in
order to create impassable obstacles for landing sea craft. First large gate-like structures
were built, simply to get in the way. The second band were large posts and logs dug into
the beach also creating obstacles. The third and final obstacle was farther up the beach,
they were large hedgehogs which were mined obstacles that looked as though they were
some sort of weird medieval art.
Like the rest of the beaches, the planned attack time (H hour) was 06:30. Many
would think that this would be when the death toll would first start to rise but this just
wasnt so. Many men died far from the beach. Two companies of amphibious DD tanks
sank because of heavy seas. Included with the 27 tanks that sunk were 11 landing craft
that tipped. Soldiers on these transports drowned because the weight of the equipment
they were carrying held them under the water. Other craft hit mines, losing troops,
supplies and weapons. Most of the landing craft were being fired upon by German
machine gun fire even when the crafts were still over 1,000 yards away from the beach.
Some even ran aground while still 100 feet from shore. Attempts to improve the situation
were made by groups such as the 29th division who decided to bring their tanks in on the
landing craft. 8 of the 16 tanks made it to the beach. Other craft either missed their
landing area or arrived too late. The lateral current dragged some infantry units 100s of
yards from their objectives and a few battalions, like the 2nd Ranger battalion arrived 40
minutes after they were scheduled to land.
Once most of the craft had managed to make it to the beach the soldiers still faced
many problems. Air strikes that were planned to knock out enemy machine gunners were
not successful enough. Most of the troops were pinned behind the sea wall and other
obstacles by machine gun fire ahead of them and the raising tides behind them. Tides rose
four feet per hour, shrinking the beach by eighty feet in the same time period. Those
soldiers who were too injured to walk or crawl drowned as the tide sped up on them. With
soldiers pinned down and not enough vehicles being able to get off the beach other craft
were unable to land due to the lack of room.
For the first few hours at Omaha Beach things looked grim. No major advances
were being made. The real turnaround that day was when a few destroyers actually came
in as close as eight hundred yards in order to fire at enemy strongpoints. The risk of
grounding the destroyers took and the arrival of tanks lead to the eventual fall of the
German beach defences. Once the groups could move inland their individual missions were
put into place.

One of the most important missions put upon any division was the destruction of six
French-made 155mm naval guns at Pointe du Hoc. This responsibility was given to the
116th brigade and its two combat teams: US 5th Ranger and US 2nd Ranger teams. The
5th met the fate of many battalions as the landed on the wrong beach. Luckily the
remaining two teams did manage to destroy the naval guns that were capable of attacking
ships as far out as 25,000 yards (22km). This would prove to be one of the few missions
that were completed that day.
Because of the great break downs in planned assaults, the day started to look like a
chaotic day with only individual missions of survival. Most divisions managed to stay
organized and plan their survival and attack plans. Col. George H. Taylor of the 16th
regiment said, Two kinds of people are staying on this beach, the dead and those about to
die, not lets get the hell out of here. These sort of speeches sparked other soldiers to
continue with their slightly revised missions. Originally it was planned for the areas above
the beaches to be taken by an advance up the heavily defended bluffs but the plan was
changed to a less organized direct assault on the German gunners in the high cliffs. Other
such companies that decided on newly created missions included the 16th infantry and the
29th division. These two groups decided on a joint mission to save their allies who were
pinned on the beach. Also involved on the Omaha Beach invasion were the US 1 Infantry
Division, and the US 18th and 115th Brigades.
By the end of D-Day on Omaha Beach the advance had gone barely one and a half
miles inland. Several of the enemy strongpoints were intact and the beachhead was still
under fire. Although this beaches day sounds like a disaster the major exits from the area
were held, three villages were under allied control and hole in the German line about two
and half kilometers long was made and the coastal guns were destroyed. The landing had
been made, all the troops could do was secure the area and organize the beach for the
introduction of reinforcements and supplies.




Gold Beach
Gold Beach was the second largest of the beaches of Normandy and was also the
middle beach: Utah and Omaha to the west and Juno and Sword to the east. Gold beach
was like most of the other beaches invaded on D-Day except it had one characteristic
which was disadvantageous to the allies. Coral reefs, ranging from twenty to a hundred
yards out could ground landing craft at low tide. Because of this factor the Gold Beach
was postponed almost an hour after most of the other attacks that day. H hour on this
beach was to be 07:25.
It turned out the this adverse condition would soon show to have its pros and
cons. The largest pro being that this left more time for bombardment of German defenses
by RAF bombers and naval guns. The cons were of course the fact that with the rising
tides men landing on the beach would end up facing the fate of many soldiers on Omaha
beach, being pinned behind a sea wall and being drowned by the advancing waves. It
would also turn out that, along with beach obstacles, the rising tide would make it even
harder for landing craft to make their transport runs.
Not soon after the arrival of the first wave of landing crafts the problems started to
mount. Also, like at Omaha, regiments decided to bring their DD Sherman tanks on their
LCD transports instead of floating them in. This was mainly because of the weather which
created high seas. Unfortunately this sort of tactic left the tanks as sitting ducks and all but
one of the tanks were disabled or destroyed. Soon one problem lead to another as those
soldiers that landed on the beach were unable to advance and were without any tanks to
bail them out of their predicament. Eventually with the help of the one tank that survived
the landing the troops at Gold Beach were able to press forward.
Not unlike any of the other beaches, Gold had a complicated battle plan including
many divisions, regiments and even a commando group. The overall goal was to take the
key points of the German defenses and secure the area. One such key point was
Port-en-Bessin which was to be invaded by the British 47th Royal Marine Commando who
would later meet up with an America regiment from Omaha. The problem was that not
everything went according to plan and they were unable to take the city and Americans
who were supposed to help in the fight inland by moving through the North-west flank of
the area never showed up.Another such joining of teams did go according to plans as the
50th division met up with a division of Canadians from Juno beach after coming within a
mile of their D-day objective of the taking of Bayeux. The only two groups to succeed in
their D-day objectives as Gold Beach were the 69th and 231st regiments. The 231st
successfully took the city of Arromanches while the 69th took la Riviere even after they
were forced to originally bypass the stronghold and return and destroy it later on. Other
groups involved included the British 8th, 151st and 56th regiments who aided in the push
inland and the clearing of the beaches of mines and obstacles.

Although a lot of the operations planned for Gold Beach went array, a few great
things did occur. A few of which, carried out by CSM Stanley Hollis, were so
extraordinary that they enabled him to be awarded with the only Victoria Cross to be
awarded the entire day of June 6, 1944. Col. Hollis of the 6th company was ordered to
check out some pillboxes(small German machine-gun bunkers). A few of his officers were
sent in to investigate and when they were twenty yards from the pillbox, a machine gun
opened fire from the slit and CSM Hollis instantly rushed straight at the pillbox, recharged
his magazine, threw a grenade in through the door and fired his Sten gun into it, killing
two Germans and making the remainder prisoner. He then cleared several Germans from
a neighbouring trench. Then when his company was pinned down by heavy machine-gun
fire Hollis managed to destroy the gun using a PIAT (Projector Infantry Anti-Tank)
weapon and retreated his troops. After learning that some of his men were still cornered in
a nearby house Hollis ran at the Germans with his gun firing allowing the men to escape.

By the end of the day most of the D-day objectives had failed but three brigades
were ready to push farther inland at sunlight. The beach was secured and ready for
reinforcements. Unfortunately Bayeux was not taken but most of the areas hidden
bunkers and trenches were. Some in fact were found to be manned by unwilling Asiatic
conscripts from the southern Soviet republics who were put there by Germans.






Juno Beach
Juno beach was Canadas beach with over 21,000 Canadians landing there. Not
unlike other beaches Junos H-hour was delayed until 07:45. The reason was that air
reconnaissance had spotted some underwater shoals (rocks/reefs) and they wanted to
wait until the tide had gone in to make it safer for the landing craft. (Later on the shoals
turned out to be masses of floating seaweed). The beach itself was wide enough to land two
brigades side by side, the Canadian 7th at Courseulles and the 8th at Bernieres.

The decision to wait until 07:45 caused more problems than it solved. The rising
tide hid most of the beach obstacles meaning two things: it was dangerous for the landing
craft to come ashore and the demolition crews couldnt get at the obstacles to make room
for the landing craft. Thirty percent of all the landing craft at Juno beach on D-day were
disabled in beach obstacle related incidents. One such example was when one craft started
to disembark troops a wave threw the craft onto a mined beach obstacle.
Like at most of the beaches that day, armoured divisions started to bring their tanks
in on the landing craft but like on all the other beaches this caused problems. The Regina
Rifles, one of the first groups to land, had to wait twenty minutes on the beach without the
aid of any tanks or heavy artillery. Due to heavy seas and tanks coming in on the landing
craft it meant that people who should have been in front were behind.The Canadians
were smarter than most in the setup of their landing. They chose a position at sea which
was only seven or eight miles out instead of the distance most other beach operations were
using of about eleven miles. This greatly increased the speed and accuracy of the landings
and the first Canadian wave was on the beach by 08:15.
Once on the beach the amount of German defences surprised the allied forces, once
again the air assault on the German gunneries were not as successful as planned. However,
like at Gold beach the Canadians did find out that the firepower of their tanks were the
difference between being able to push inland and being pinned down at the beach. After
the main beach defences of the Germans were taken the inland push became slower and
slower the farther south they got.
A few of the main objectives were successful. The 3rd division reach the
Caen-Bayeux road and a lot of French towns were liberated. The French residents were
very welcoming and greeted us heartily in the midst of the ruins of their homes. The one
strongpoint that would become a problem for troops at Juno as well as Sword would be
Caen. The Canadians found increased resistance the closer they got and in that aspect
their D-day mission did not succeed.
As night fell the Canadians were still well short of a lot of objectives. They did get
their tanks on the Caen-Bayeux road but that was about it. The British 3rd division from
Sword beach was planned to meet up with the Canadians in order to close the gap between
Juno and Sword beaches but they never showed. This left a two mile gap in the beaches
and would be the area of the only German counterattack of the day. The other linkup
between beaches was successful as Canadians met the 50th division from Gold beach.
Overall the Canadians didnt get all that far but were in a good position to move inland.





Sword Beach
Sword beach was the easternmost beach in Normandy. Like at Juno Beach H-hour
was again postponed because of shoals until 07:25. The main objective at Sword beach
was to advance and invade the German strongpoint of Caen. Four whole brigades of the
3rd division were sent to Caen. There were also airborne divisions that dropped behind
lines using large gliders which could carry troops as well as other armoured vehicles. Those
groups not supposed to head toward Caen were planned to reach the airborne divisions
and secure the areas bridges from counterattack.
Even as the Canadians moved inland trouble was developing back at the beach.
Although all the DD tanks made it to the beach the tide was turning the already small
beach into one with only ten yards from the seafront to the waters edge. With only one
road off the beach the overcrowding caused delays in most objectives for that day. Some
of the armoured divisions like the 27th armoured Brigade abandoned their objectives in
order to bail out infantry pinned down on the crowded beaches.
Those who did make it off the beach in time were quite successful in reaching their
D-day objectives. By late afternoon the leading troops of the brigades heading for Caen
had reached and liberated the towns of Beuville and Bieville which were only two or so
miles short of Caen. Strongpoints like the one at La Breche were taken as early as 10:00.
Those troops that didnt make it off the beach in time like the 185th Brigade had to leave
all their heavy equipment behind in order to catch up with the forces already nearing
Caen.
The move inland was really looking quite promising until the Germans launched the
only counterattack of the day. The 21st Panzer division was sent out from Caen, half to
take on the southward allies and the other half to head right up between Juno and Sword
beach where that two mile of beach was unoccupied by allied forces. Fifty German tanks
faced the brigades heading for Caen. Luckily the British were ready with artillery,
fighter-bombers and a special Firefly Sherman tank that was fitted with a seventeen
pound anti-tank gun instead of the normal seventy-five mm. gun. Soon thirteen of the
German tanks were destroyed with only one M-10 tank destroyer damaged. This just went
to show that the British were slow in advance but almost unbreakable in defence. Still
the Germans pressed forward until about 21:00 when the last wave of gliders of the 6th
airborne divisions came in. The Germans looked up and saw about two hundred and fifty
gliders fly in and land behind them. The allies now were attacking from two directions and
the only German counterattack ended quickly.
By the end of the day the German resistance at Sword beach was almost obliterated
other than at Caen. A lot of the success was because of the joint effort of airborne divisions
and divisions landing on the beach. Of the 6,250 troops of the 6th airborne that landed
there were only 650 casualties. Unfortunately Caen was not taken but its liberation was
imminent.



D-Day Air Battle
D-day was not only a day of troops landing on the beaches of Normandy and
moving inland liberating France. Without the aid of the thousands of planes Operation
Overlord could not have gone as planned. As early as the spring of 1944 planes flew over
German ruled France taking photographs of the defences. During the ten week period
before June 6 countless missions were flown with objectives of taking out German radar
installations. There were also hundreds of attacks on the railways of the area in order to
immobilize the forces. Of the 2,000 locomotives that were in the area the year before 1,500
of them were destroyed or disabled by allied bombings.
By the eve of D-day the allies had 2,800 heavy bombers, 1,500 light bombers and
3,700 fighter planes and fighter-bombers. They also had 56 special night bombers.
When June 6, 1944 came around all the squadrons of planes involved had their
missions just as the landing infantry divisions had theirs. It took six squadrons of RAF
Mosquitoes to patrol the huge armada of ships in the English Channel that day. Without
whom there would have some serious repercussions on the entire operation. At all times
there twenty anti-submarine planes patrolling the area and protecting the force who would
have been sitting ducks for any German U-boats that would have gotten into the area.
To aid the actual landings of the troops squadrons flew bombing missions on
German pillboxes and other gunnery installations. Flying at three hundred miles per hour
straight in at German machine gun fire in order to clear the way for others to take the
glory is what I call guts. In order to clear the three British beaches eighteen squadrons flew
missions over a nearly continuous eight hour time period. When bombers werent
destroying installations they were setting up smoke screens around the land based naval
guns in order to once again protect the allied armada.
Probably one of the most important things done by the fighters was to fly phantom
missions in order to make the Germans think that the invasion would by at Pas de Calais.
Without the use of air firepower as used on D-day I can say without a doubt that
June 6, 1944 would be remembered as a day of complete disaster.




Conclusion
By the end of June 6, 1944 one of the most complicated and the most coordinated
invasions had started. On the beach codenamed Utah the American 1st army held a firm
beachhead with several divisions already receiving the supplies they needed and would
soon be ready to move inland. On Omaha the troops there had recovered from what had
looked like an impending disaster in the first hours and started to break through the
German defences. At the British run beaches of Juno, Gold and Sword the forces had
averaged a push inland of six miles. Even with the amount of landing soldiers numbering
about seventy-five thousand, the casualties between the three beaches were only
approximately three thousand.
D-Day was the beginning of the end for the Germans in Europe and the end of the
beginning for the fight for Europe. Im not saying that everything went according to plan
on D-day and there wasnt any errors. I am also not saying that it was a complete disaster.
I am saying that D-Day was on paper, with objectives for each division and a craft for each
infantry unit, the greatest battle of all time.


Table of Contents
I. Introductionpg. 1
II. Preperation for D-Daypg. 2
III. Beachfronts
A. Utah Beachpg. 4,5
B. Omaha Beachpg. 7,8
C. Gold Beachpg. 10, 11
D. Juno Beachpg. 13
E. Sword Beachpg. 15
IV. D-Day Air Battlepg. 17
V. Conclusionpg. 19
VI. Bibliographypg. 20


Bibliography
D-Day June 6, 1944: The Climatic Battle of World War II
Stephen E. Ambrose,
Simon &
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