Mark Flanner- An Analysis of the Central Fuel Tank Explosion of TWA Flight 800

8/3/2019 Mark Flanner- An Analysis of the Central Fuel Tank Explosion of TWA Flight 800

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An Analysis of the Central Fuel Tank Explosion

of TWA Flight 800

By Mark Flanner


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Causes and Effects of the Central Fuel Tank Explosion

in TWA Flight 800

submitted to

theUndergraduate Engineering Review

On July 17, 1996, TWA Flight 800 exploded in midair, killing all 230 people aboard. Investigatorsknow that an explosion in the central fuel tank of the plane caused the disaster. However, they still donot know why the tank exploded. Because of this uncertainty, there is a need to utilize the informationthat we have about the dangerous conditions residing in the TWA Flight 800 case to prevent arecurrence of the disaster. This report examines possible ignition sources for the explosion and factorsthat created a dangerous fuel-air mixture. Based on these examinations, the report recommendschanges that could be made to improve safety in commercial jets.


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CONTENTS

Introduction

General Theories of ExplosionMissile TheoryBomb Theory

Conditions of the Central Fuel TankThe Ignition Source

Electrical ArcingAutoignition

Recommendations to Minimize Ignition Sources

Fuel CombustibilityFuel-Air RatioRecommendations to Reduce TemperatureFuel Type

Conclusion

Appendix A: Events of TWA Flight 800

Appendix B: Listing of Jet Ages by Major Airlines

Glossary

References

Figures:

Figure 1: Schematic of central fuel tank

Figure 2: Depiction of faulty check valve scenario

Figure 3: Diagram showing position of air conditioner units

Figure 4: Chart comparing central fuel tank temperatures whendifferent quantities of fuel are present

Figure 5: Graph showing Jet A flammability boundary as afunction of temperature and altitude


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INTRODUCTION

Twenty minutes after taking off from New Yorks JFK International Airport on July 17, 1996, Paris-

bound TWA Flight 800 exploded. All 230 passengers were most likely killed from what medicalexaminers described as phenomenal whiplash [Smith, 1998]. It is widely accepted that an explosionin the central fuel tank of the aircraft caused its destruction. However, it is unclear exactly whatcaused this explosion. To this day researchers continue to examine retrieved parts of the airplane andother similar models to seek explanations for Flight 800s explosion. There were several factors thatmade TWA Flight 800 a ticking time bomb. Many of these factors could still be present in thethousands of jet flights that occur every day.

The purpose of this report is to explain why the conditions in TWA Flight 800 were dangerous and tosuggest changes that can be made to commercial jets to reduce the risk of explosion in central fueltanks. The two key factors that contributed to the dangerous environment for TWA Flight 800 were

the condition of the aircrafts electrical hardware and the presence of a highly explosive fuel-air ratioin the central fuel tank. This report examines factors that could account for an ignition source, such asa spark or localized heating within the tank. The report also analyzes the roles that temperature,amount of fuel present, and fuel type can play in producing a dangerous fuel-air mixture.

Many people still believe that a missile or bomb caused the TWA Flight 800 explosion. Therefore, thefirst section of this report evaluates the weaknesses in these theories. The report also analyzes thetheory of mechanical failure possibly producing the explosion and addresses effects of the explosionfrom a mechanical perspective. Following this section, the issues of ignition sources and fuelcombustibility are discussed at length. Finally, recommendations to help prevent a recurrence of theTWA Flight 800 disaster are summarized in the conclusion.

GENERAL THEORIES OF EXPLOSION

Before exploring reasons for the TWA Flight 800 explosion, a few relevant facts about theenvironment and details about the plane itself are essential. The TWA Flight 800 plane was a 25 year-old Boeing model 747-131. The 131 is an early model of the 747, which is the largest commercialairplane in the world. After arriving at JFK International Airport from Athens, Greece, the plane sat onthe ground for four hours with the air conditioning units operating before departing for Paris at 8:19p.m. The plane exploded 20 minutes later, while ascending at 13,760 ft. (Appendix A).

The central fuel tank, which is capable of holding 13,000 gallons of jet fuel, only contained 50 gallonsat the time it exploded, meaning that it was less than one-half percent full. TWA Flight 800 was usingJet A fuel, which is the most commonly used fuel for commercial jets. The central fuel tank is locatedon the underside of the fuselage, directly between the wings (Figure 1). Following the mysteriousexplosion, a host of theories arose speculating the cause.


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Figure 1. Schematic of a central fuel tank, including dimensions and partitions, and its relative position in a Boeing 747from a side view. The central fuel tank, which is also commonly called the center wing tank, is labeled as CWT(modified from NTSB d, 1997).

MISSILE THEORY

The first theory speculates that someone shot down TWA Flight 800. Conspiracy buffs wereimmediately aroused because the plane exploded over area W-105, a restricted military zone off thecoast of Long Island where the Navy conducts training operations. The friendly fire theory assumesthat a Navy vessel in this area accidentally shot down TWA Flight 800. Spread[ing] with dizzyingspeed on the Internet, information was reported about the presence of a nearby Navy vessel notresponding to initial crash reports and eye witness accounts of a streak of light shooting towards theplane [Vankin, 1996]. Much of the information, however, was falsified or based on rumors.


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The friendly fire theory lacks solid evidence. The FBI independently verified the Navys accountthat their nearest vessel was 180 miles away from the explosion site, which is far out of the surface-to-air missile range. The mere size of the conspiracy that would be required to cover up an accidentaldowning of Flight 800 is mind staggering. Hundreds of people, including sailors, Navy divers, NTSBcrash investigators, FBI agents, medical examiners, and pilots would have had to be a part of the

conspiracy. Furthermore, 95% of the exploded craft is pieced back together in a hangar that has beenopened to public viewing, and it is no longer possible to fit a metal rod the size of a missile throughany reasonable gap in the wreckage [Van Natta, Jr., 1996].

BOMB THEORY

The more likely theory that gained momentum was that a bomb exploded in the plane. Only a bombcan create an explosion powerful enough to down a plane the size of a Boeing 747. Also, manysimilarities exist in circumstance to the Pan Am Flight 103 explosion, which was indeed caused by abomb. Furthermore, TWA Flight 800 originated at Hellenikon airport in Athens, Greece, which has avery poor reputation for security. Theories of terrorism heightened when the FBI discovered RDX and

PETN on the plane wreckage. Both are chemical compounds of the Czech plastic explosive SEMTEX,which is thought to have composed the explosive device destroying Pan Am Flight 103 [Fedarko,1996].

While it initially seemed the most plausible explanation, no concrete evidence to support the bombtheory exists. Only trace amounts of RDX and PETN were found on the wreckage, and it wasdiscovered that a bomb-sniffing test had been conducted with dogs less than two months prior to theexplosion on the plane of TWA Flight 800 [Fedarko, 1996]. Packages containing small amounts ofPETN and RDX most likely explain the trace amounts found on the wreckage. Furthermore, the FBIended its investigation in November of 1997, announcing that it had found no evidence of a criminalact.

What many people have failed to realize is that the central fuel tank of the large commercial jet canbecome a huge bomb that is capable of ripping the plane apart in certain conditions. The NTSB hasconfirmed that the central fuel tank of TWA Flight 800 exploded. Since there is no convincingevidence to suggest that a bomb or missile caused this explosion, we must assume that some fatal flawin the conditions in or around the tank caused it to explode.

CONDITIONS OF THE CENTRAL FUEL TANK

There are many different angles from which to approach the issue of central fuel tank safety incommercial jets. The most obvious approach recognizes that there must be an ignition source for an

explosion to occur. Identifying the ignition source in the TWA Flight 800 case has been the million-dollar question that is still unanswered. This section will examine the role of electrical hardware inand around the central fuel tank that could cause an ignition. Another necessity for an explosion tooccur is the presence of combustible matter for the ignition source. Tank temperature, fuel-air ratio,and fuel flammability are all relevant issues in this case and determine how ignitable the central fueltank is.


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THE IGNITION SOURCE

Upon realizing that the central fuel tank of TWA Flight 800 exploded and that the explosion was notlikely caused by a bomb, the NTSB investigation focused on finding the source of ignition. However,after scrutinizing all of the recovered wreckage, which accounts for over 95% of the plane, they foundnothing to support any plausible theory of ignition. The investigation focused on examining theelectrical wiring near the central fuel tank, which consists largely of wiring for thefuel quantityindicating system (FQIS)

* [McKenna, 1999] and for control of the fuel pumps. Unfortunately, most

of this wiring was burned or damaged from the explosion, thus hindering an analysis into the role thatit could have played in causing the explosion. However, this did not leave the NTBS completely in thedark concerning ignition sources. Electrical arcing and autoignition are two source theories that weretested by the NTBS.

Electrical Arcing

In search of answers to the question of ignition, the NTSB conducted an investigation into the state ofelectrical wiring in operational Boeing 747s and similar models from other manufacturers to see if aspark could occur in the central fuel tank. The findings from this investigation were discouraging.Between May of 1997 and July of 1998, the NTSB examined 43 existing jets [NTSB b, 1999], ofwhich many were old, reaching ages up to 27 years old. Findings include sharp metal shavingsboth on and between wires in bundles [NTSB b, 1999], and three-quarter inch coatings of lint onwires, what NTSB investigators describe assyrup: a sticky combination of spilled beverages, leakingwater and lavatory fluids, dust and other materials that build up over years of service [McKenna,1999].

The presence of sharp metal shavings, which can be attributed to drilling, can strip insulation awayfrom the wires. As a result, the core conducting wires become exposed and enhance the likelihood of aspark. Exposed wires that are coated with syrup or metallic drill shavings can be dangerous becauseeither substance can act as a conductor. Consequently, substances such as these could function as abase point for an electrical arc, which could ignite the contents of a fuel tank. The NTSB, working inconjunction with the contracted Lectromechanical Design Company, conducted simulations with theseconditions to see if it was possible to create an electrical arc. In one rare case, when two bare wireswere bundled close to each other, an arc was created [NTSB c, 1999].

Autoignition

Another possible source of ignition is from the terminals of the FQIS wires in the central fuel tank onwhich copper sulfide can build up. This phenomenon has been observed in aging electrical systems[NTSB b, 1999], and is a result of the natural deterioration of wiring. The buildups can become sourcesof localized heat [McKenna, 1999]. This can cause a threat because ofautoignition. If the localized

* All terms in bold italics are defined in the glossary.


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heat source is hot enough, the fuel around it may reach a temperature at which it will automaticallyignite.

Another theory of how autoignition could have occurred within the central fuel tank of TWA Flight800 involves thescavenger pump and faulty check valves [Tischler, 1998]. The scavenger pump is a

possible source of ignition because it resides within the central fuel tank. NTSB officials believe thatfuel was being transferred between tanks when the explosion occurred, suggesting that the scavengerpump in the central fuel tank was operating. If the scavenger pump was operating and its check valvewas too tight, it may have allowed only fuel, and not vapor to pass through it, resulting in aconcentration of vapor around the check valve of the scavenger pump. The vapors have a lowerautoignition temperature than the liquid fuel and the pump is a significant source of energy that couldbecome hot enough to cause autoignition of fuel vapor. A depiction of this scenario is shown in Figure2.

Figure 2. Depiction of a theoretical scenario in which a faulty check valve in the scavenger pump only allows fuel, and notvapor to pass through. The scavenger pump could generate enough energy to heat the vapors to the point where theyautoignite.

Recommendations to Minimize Ignition Sources

The odds of one of these conditions causing the fuel to ignite in the central fuel tank are slim, but theystill must be prevented from ever occurring. One key area for prevention is by regularly inspecting thewiring. Stripped insulation, which can lead to arcing, and copper sulfide buildup on FQIS terminals,which can create autoignition, would be discovered and be fixed. Inspectors should examine checkvalves and localized heat sources within the scavenger pump. Also, a cleaner environment should bemaintained around the central fuel tank to prevent the buildup of possible conducting agents such as

Flow Out ScavengerPump

Fuel Vapor

Faulty Check Valve

Heat

Flow In

Central Fuel

Tank


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drill shavings and syrup. Finally, the risk of arcing could be reduced if more durable insulation thatcovers electrical wiring is installed in new and old commercial airlines. This improvement may beespecially important, as the average age of operational planes is steadily increasing. A chart showingthe ages of planes owned by different airlines is in Appendix B.

FUEL COMBUSTIBILITYIn order for an explosion to occur, there must be a combustible substance in addition to an ignitionsource. After failing to discover an ignition source for the central fuel tank explosion, NTSB officialsshifted their focus to the issue of fuel combustibility. When the FAA attacked the NTSB for notidentifying an ignition source, one senior NTSB official was quoted as saying, Whether we identify aspecific ignition source is almost irrelevant. For one that we do identify, there may be 10 others thathave not been engineered out of the tank yet [McKenna, 1998]. In terms of safety, it is as productiveto reduce the combustibility of contents in central fuel tanks, as it is to identify ignition sources.

A substances degree of combustibility determines the likelihood of an explosion occurring. In the

environment aboard TWA Flight 800, several factors increased the degree of combustibility of thecontents of the central fuel tank. They include fuel-air ratio, temperature, pressure, and minimumignition energy. By understanding these factors, it may be possible to prevent future disasters.

Fuel-Air Ratio

Fuel vapor is the most dangerous element in a fuel tank because it combusts easily. Thefuel-air ratioin an enclosed environment, for a given fuel, is a good indicator of how easily an explosion can occur.The fuel-air ratio increases as fuel evaporates and mixes with the surrounding air. The two key factorsthat affect the fuel-air ratio in a closed environment are temperature and pressure.

The temperature inside the central fuel tank of TWA Flight 800 was unusually high, and probablyplayed a significant role in the explosion. When fuel is heated, a greater portion of it exists as vapor,thus increasing the fuel-air ratio. NTSB officials, who originally thought that the temperature in the

central fuel tank was 36C (97F), now think that the temperature was at least as high as 46C (115F)

[NTSB d, 1997] and maybe as high as 53C (127F) [McKenna, 1997b]. Boeing has performed

simulations that show that on a 27C (81F) day, fuel vapors in the central fuel tank of a 747 are in anexplosive state for 4of the 6 hours on a typical flight [Adcock, 1998].

There are several reasons why the temperature in the central fuel tank was so high. First, after arrivingfrom Athens, the plane sat on the ground for about four hours before departing for Paris. Due to thesummer heat, the planes air conditioners were left running for this period [Tischler, 1998], which is

unusually long. Ironically, the air conditioners warm the central fuel tank, as they are located directlybelow it and do not blow cool air into it (see figure 3). Secondly, since there was so little fuel in thecentral fuel tank, less energy was required to heat it. The tank would have heated more slowly if it hadbeen full. The NTSB performed tests to compare temperatures in the central fuel tank during flight at13,800 ft. with 50 gallons of gas (the amount in Flight 800) and with 12,000 gallons (almost full). Theresults of this test (see figure 4) clearly indicate that the contents of the tank heat more when there isless fuel present.


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Figure 3. A diagram showing the position of the air conditioning units, labeled AC, in relation to the central fuel tankfrom a front view of the plane. In a 747 there are actually three air conditioning units below the central fuel tank, but only

two are shown here (modified from: NTSB d, 1997).

In addition to temperature, pressure (or altitude) affects the fuel-air ratio. As altitude increases, morefuel evaporates due to decreasing ambient pressure. Therefore, the fuel-air ratio increases withincreasing altitude. A graph representing the relationship between the minimum temperature neededfor an ignition of Jet A fuel and altitude is shown in Figure 5. As this chart illustrates, the minimumtemperature needed to ignite the fuel decreases as the altitude increases. The minimum flammability

temperature at 13,800 ft. is about 26C (79F), well below the reported temperature of 46C (115F) inthe central fuel tank of TWA Flight 800.

AC AC


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Figure 4. A bar chart comparing recorded temperatures in different areas of a 747 central fuel tank during tests that wereperformed when the tank was nearly empty and about half full. The tests were carried out at 13,800 ft, the same altitude atwhich TWA Flight 800 exploded [NTSB e, 1997].

- 5 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 0

0

5

1 0

1 5

2 0

2 5

3 0

3 5

4 0

4 5

5 0

Flammability Boundary of Jet A Fuel

Temperature (C)

Altitude

(thousands

offeet)

Figure 5. A graph depicting the flammability boundary of Jet A fuel with respect to temperature and altitude. The fuelbecomes flammable at a lower temperature as the altitude increases (generated using information from: NTSB d, 1997).

Until recently, a key point that has been neglected is that the minimum ignition energy needed to ignitethe fuel also decreases with increasing temperature. Researchers at California Institute of Technology,

performing tests for the NTSB, found that by increasing the temperature in a fuel tank from 38C

(100F) to 60C (140F), the ignition energy required is reduced by a factor of 100,000 [Wilkinson,

Flammable


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1997]. This exponential relationship means at higher temperatures, a very weak spark will causeignition. In other words, the fuel-air ratio, temperature, pressure, and ignition energy combined onFlight 800 to create a unique environment highly conducive to explosion.

Recommendations to Reduce Temperature

Keeping the temperature low is essential in order to keep the fuel-air ratio low in the central fuel tanks.The main source of heating appears to be the air conditioning units. Because moving the airconditioner units away from the central fuel tank would require a significant amount of airplaneredesign, a more practical solution to this problem is to add insulation between the air conditioners andthe central fuel tank. Efficient insulation would drastically reduce the heat transfer to the central fueltank. Another way to reduce heating is to minimize the duration of time the air conditioners arerunning while the plane is on the ground. A final recommendation for minimizing the temperature inthe central fuel tank is to keep a large quantity of fuel in the tank. A larger mass requires a largeramount of energy to heat; therefore, heating will occur more slowly.

Fuel TypeThe fuel-air ratio in the central fuel tank is a key issue in determining combustibility. A more basicfactor of combustibility, though, is the nature of the fuel itself. Although different fuels may haveidentical fuel-air ratios, they will have differentflashpoints. Consequently, one way to reduce the riskof combustion is to use a fuel that has a higher flashpoint. One such fuel is JP-5.

JP-5, a fuel used by the United States Navy and Air Force, is similar to Jet A fuel except that it has a

flashpoint 4.4C (40 F) higher than Jet A fuel [Wilkinson, 1997]. Using a fuel that is more difficult toignite should eliminate midair fuel explosions. All Boeing aircraft are currently certified to operatewith JP-5 fuel [McKenna, 1997a], but only if that is the only fuel available when they need to refuel.Thus, if a transition were to be made from Jet A fuel to JP-5, aircraft design would not need to bechanged.

However, certain consequences need to be addressed in considering such a transition. Petroleumrefineries are set up to convert a specific percentage of crude oil that they receive to Jet A fuel, as theairline industry purchases 12.7 billion gallons of it annually [Adcock, 1998]. To convert the refineriesso that they produce JP-5 fuel instead would be a very costly and controversial maneuver.Furthermore, at a cost of two cents more per gallon for JP-5 fuel, commercial airlines would be facinga $241 million increase in annual fuel expenses [Adcock, 1998]. This added expense would be shiftedto the consumer. Finally, there is an ironic safety concern with JP-5 fuel. Fuels with higherflashpoints make it harder for engines to start in cold weather. If a plane were to lose engine power inmidair, it may be unable to restart the engine in very cold weather [Adcock, 1998].

Due to these factors, it is impractical to convert all commercial jet fuel to JP-5. The costs involved insuch a conversion would not make this a viable alternative. Implementing the fuel change worldwidewould prove to be difficult as the smaller airlines in second and third world countries would struggle tocompete due to the heightened prices of fuel. Furthermore, the safety concern of cold weatheroperation offsets the safety benefits that a transition to JP-5 fuel would bring.


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CONCLUSION

Information gathered about the explosion of the central fuel tank in TWA Flight 800, and fromresulting research, offered insight into factors that yield a dangerous environment for commercial jets.

This information includes no evidence to support theories that a missile or bomb caused the explosion.While not pointing to an exact source of the explosion, the information does lead to factors that make iteasier for an explosion to occur. The information learned from this tragedy should be applied tocurrent operational jets so that improvements can be made, eliminating the recurrence of such adevastating tragedy. The two most probable causes of the explosion were the presence of both anignition source and a combustible substance. These are the areas that improvement is needed to assureproper safety for commercial jets.

It is crucial to consider the state of the electrical hardware in and around the central fuel tank whenaddressing improvements that can be made to deal with possible ignition sources. Regular inspectionrequirements do not currently exist in any consistent form. Implementing these regular inspections

would lead to the detection of stripped insulation, accumulated copper sulfide on the FQIS terminals,and faulty check valves in the scavenger pump. These conditions can all lead to electrical arcing,localized heating, and induced autoignition. In addition, many aircrafts electrical systems arerelatively old. Therefore, the installing of tougher insulation in future planes could reduce thepossibility of stripping. Finally, more stringent regulations on maintenance and routine inspectionswill prevent the buildup of potentially dangerous conductors such as drill shavings and syrup.The second probable cause of the explosion is the existence of a combustible substance. Chemicalproperties of the fuel are the most important factors in determining combustibility. JP-5 is analternative to Jet A fuel that has a lower flashpoint. Unfortunately, converting to JP-5 fuel would haveextreme cost concerns, and would also pose a potential safety problem in starting engines in coldweather. Therefore, it is more reasonable to consider factors that affect the fuel-air ratio with Jet A

fuel. It is imperative to keep the temperature within the central fuel tank as low as possible to reducethe opportunity for explosion. Adding insulation between the air conditioning units and the centralfuel tank could drastically reduce heat transfer to the central fuel tank. Another way to reduce heattransfer is to minimize the time that the air conditioners are running, especially while the plane is onthe ground. Finally, a significant amount of fuel should be kept in the tank at all times so that the fuelwill heat up slower.

Neither the condition of the electrical hardware, nor the presence of a high fuel-air ratio will alonecause an explosion with the magnitude of TWA Flight 800. However, the combination of the two willproduce an environment that could lead to an explosion of that proportion. The only justifiableimprovements that could be made to prevent another horrific incident such as TWA Flight 800 would

be to implement a more robust electrical system, reduce the air-fuel ratio, and introduce mandatorysafety evaluations at regular time intervals on the previously stated causes of explosion.


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Appendix AEvents of TWA Flight 800

Source: Newsday.com


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Appendix BListing of Jet Ages by Major AirlinesSource: Back Information Services (via Newsday.com)


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GLOSSARY

autoignition: the ignition of a combustible substance caused by temperature, or kineticenergy, alone.

check valve: a valve that only allows flow in one direction.

electrical arc: a fast current of electricity through air, caused by discharge betweenpoints with high electric potential. An electrical arc will occur when the electric potentialbetween two sources is great enough to induce an electric field in the air between themthat is strong enough to cause the air to break down.

flashpoint: the minimum temperature at which fuel vapors ignite if exposed to a flame.

fuel-air ratio: a ratio of the mass of fuel vapor to the mass of air in a particular

environment.

fuel quantity indicating system (FQIS): electrical system in jets that uses multiplemethods to measure the amount of fuel in a tank and report the data to the cockpit.

scavenger pump: a small fuel pump that resides in the central fuel tank of commercialjets. Its purpose is to empty fuel residing in the central fuel tank after fuel has been drawndown to the level of the inlets of the principal fuel pumps.

syrup: a sticky combination of spilled beverages, leaking water and lavatory fluids, dustand other materials that build up over years of service NTSB.


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REFERENCES

Adcock, Sylvia, A Quest for Safer Jet Fuel,http://www.newsday.com/jet/year/twa1207.htm

(Newsday; New York, December 1998)

Deitz, D., FEA Makes Airframes Safer,http://www.memagazine.org/backissues/january98/features/airframe/airframe.html (American Society of Mechanical Engineers; New York: January1998).

Fedarko, Kevin, A Theory Gone to the Dogs, Time (September 30, 1996); p.32.

McKenna, James T. Debate on Wiring Safety Shifts to Capitol Hill Aviation Week &Space Technology, vol. 151, no. 11. (September 13, 1999); p. 57-58.

McKenna, James T. NTSB Sees End to TWA 800 ProbeAviation Week & SpaceTechnology, vol. 149, no. 3. (July 20, 1998); p. 37.

McKenna, James T. Boeing Eyes Fuel Change to Increase Tank SafetyAviation Week& Space Technology, vol. 147, no. 24 (December 15, 1997a); p. 33.

McKenna, James T. TWA Probe Targets Aging Aircraft Systems Aviation Week &Space Technology, vol. 147, no. 24. (December 15, 1997b); p. 30.

National Transportation and Safety Board,Public Hearing Exhibit Items - TWA Flight 800 (November 1997 October 1999)http://www.ntsb.gov/Events/twa800/exhibit.htm

a: Item 9A- Systems Group Chairman's Factual Report (November 1997)b: Item 9A- Addendum 3 Concerning Wire Inspections (July, 1999)c: Item 9A- Addendum for Electrical Short Circuit/Arcing of AgedAircraft Wiring (October, 1999)d: Item 20D- Jet A Explosion Experiments: Laboratory Testing(November 1997)e: Gallery of Images from the Public Hearing (December, 1997).

(http://www.ntsb.gov/Events/twa800/gallery.htm)

Newsday.com, TWA Flight 800 - Graphics (July, 1996 October, 1998).http://www.newsday.com/jet/twamain.htm

Smith, J.B., Boeing 747, http://www.corazon.com/ (1996-1999).


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Tischler, Adelbert O. What Happened to Flight 800Aerospace America, vol. 36, no. 3.(March 1998); p. 30.

Van Natta Jr., D. In Flight 800 Crash, 3 Revised Theories, Lacking a 'Eureka.'NewYork Times, (November 5, 1996); p. B6.

Vankin, Jonathan. How a Quack Becomes a CanardNew York Times Magazine,(November 1996); p. 56-57.

Wilkinson, Sophie, Fuel Change May be Flight 800's Legacy Chemical & EngineeringNews, vol. 75, no. 51 (December 22, 1997); p.10.

Mark Flanner- An Analysis of the Central Fuel Tank Explosion of TWA Flight 800

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