Boeing 747


Rupture at Midspan Latches of Cargo Door in Flight
Probably Caused by Wiring/Electrical Fault

Accidents
TWA 800, UAL 811, PA 103, AI 182 and possibly CI 611


Copyright John Barry Smith 1996, 1997, 1998, 1999, 2000. 2001, 2002, 2003, 2004 through 2010 PDF files for Smith AARs for TWA Flight 800, Pan Am Flight 103, and Air India Flight 182 available at http://www.planetofearth.com The shorted wiring/unlatch motor on/ruptured open forward cargo door/explosive decompression/inflight breakup explanation for AI 182, PA 103, UAL 811, TWA 800.  The manufacturing installation of faulty wiring needs to be replaced and the design flaws of omitted midspan locking sectors and non plug cargo doors needs to be corrected. These Smith AARs and this website are the work of John Barry Smith, an independent aircraft accident investigator not affiliated with any government agency, or regulatory departments, or law enforcement, or attorneys, or manufacturer, or airlines, or publishers, or unions, or media. John Barry Smith has over fifty years experience in many aspects of aviation and loves airplanes more than most, in particular, the Boeing 747 and its models. The 747 is a magnificent aircraft which has proven itself over the decades to become a truly classic aircraft.  The typical pattern in aviation progress has been to imagine the aircraft, create it in writing, build it with materials, test it by flying, break it by time, find the problem, fix it, fly it, break it, find the problem, fix it, fly it….. There have been a few aircraft types which have had fatal manufacturing defects and design flaws which were not fixed or modified. Those models did not sell well and were discontinued due to poor sales. The manufacture and export of commercial airliners is a major source of revenue for the business of Boeing and for the USA. Safe airplanes sell better than ones which have accidents from mysterious or controversial causes. All the probable causes can’t be anticipated or fixed but some can and it is the duty of the manufacturer to do so. There is much pressure on the manufacturer of the aircraft, the airlines that fly them, and the government that oversees them to deny that serious problems exist in accident aircraft and succumb to the temptation to blame others and hope for the best. There are no conspiracies in the mechanical explanation of shorting wiring causing a cargo door to open in flight. There are no bombs, no bombers, and no agencies conspiring to hide the mechanical explanation. There are just individuals who are acting in their own perceived best interests, mistaken as they are. The early model Boeing 747s, 100 and - 200, have a manufacturing defect in that faulty wiring, Poly-X type, was installed. The wiring insulation was prone to cracking and chafing and exposing bare wire especially in the presence of moisture. When the bare wires shorted the sparks caused fires which were not uncommon events. Later models, 300 and 400 used a different type of wire. There is a specific design flaw in the two large main cargo doors of all Boeing 747s; the two midspan latches do not have locking sectors while the bottom eight latches do. These locking sectors are very important to prevent the door latches from being backdriven inadvertently leading to the accidental opening of the cargo door and the catastrophic explosive decompression which follows if at altitude. There is a general design flaw in all Boeing 747s and indeed in the many thousands of airliners in service today: Non-plug cargo doors. As the aircraft climbs and the pressure differential inside cargo bay and the outside air becomes greater, the force exerted on the doors increases and yet there are only the ten latches and a hinge holding the almost ten foot square door closed. The passenger doors are plug type which means as the pressure differential increases the door becomes harder, if not impossible to open. All airliners should have plug type doors on all the doors so that they become almost impossible to open in flight regardless of the status of the latches. The seal becomes tighter not looser, as the aircraft climbs to cruising altitude when the door is plug type. With new lighter stronger composite materials available, new cargo doors can be made and installed which will be a vast improvement in strength and safety when designed to also be plug type. For one Boeing 747-100, the faulty wiring exploited the two design flaws and caused the deaths of nine passengers and almost killing several hundred: UAL Flight 811. It was eventually determined, after first believing a bomb had caused the event, and later an improper door latching by ground crew, that a failed electrical switch or faulty wiring caused the forward cargo door to open in flight causing an explosive decompression. That open cargo door event for UAL Flight 811 left much evidence in the form of cockpit voice recorder data, twisted metal, paint smears, damaged engines, broken cargo door, missing latches, and damage to the fuselage. It is the belief of John Barry Smith that there are at least three other early model Boeing 747 fatal accidents which were caused by the same reasons: Faulty wiring exploiting design flaws. The causes for those other three are officially given as bomb or center fuel tank explosion. The evidence from the indisputable, irrefutable event of UAL Flight 811 matches TWA Flight 800, Pan Am Flight 103, and Air India Flight 182 so closely that the one clear cause of one, electrical, is the cause for all. When a rational, reasonable alternative explanation with support documentation and precedent exists for controversial aircraft accidents, it is the duty of the manufacturer, the airline, and the government to examine and consider such an explanation. Such an explanation is the shorted wiring/unlatch motor on/ruptured open forward cargo door/explosive decompression/inflight breakup explanation for TWA Flight 800, Pan Am Flight 103, and Air India Flight 182. This website presents that evidence.

Above is Aviation Safety Council of Taiwan picture of the top part of the aft cargo door for China Airlines Flight 611. Also shown is the bottom part of the aft cargo door of China Airlines Flight 611. Note vertical tear lines in skin above door, missing pressure relief doors, intact hinge, longitudinal split, missing lower part, and general shattered appearance of door. Those observations are similar to other cargo doors of early model Boeing 747s that have ruptured open in flight. On bottom part of aft cargo door note detached latches near bottom of picture.


 

Above is AAIB UK photo of the forward cargo door of Pan Am Flight 103. Note vertical tear lines in skin above door, missing pressure relief doors, intact hinge, longitudinal split, missing lower part, and general shattered appearance of door. Those observations are similar to other cargo doors of early model Boeing 747s that have ruptured open in flight.


 

 

Above on left is NTSB photo of aft midspan latch area of the forward cargo door and above on right is private photo of forward midspan latch area of the forward cargo door of Trans World Airlines Flight 800. Hinge is on top. The petal shaped bulges in both pictures are at the aft and forward midspan latches Note vertical tear lines in skin above door, missing pressure relief door, intact hinge, longitudinal split, missing lower part, and general shattered appearance of door. Those observations are similar to other cargo doors of early model Boeing 747s that have ruptured open in flight.


Smith Table for Matches for Air India Flight 182, Pan Am Flight 103, United Airlines Flight 811, Trans World Airlines Flight 800, and China Airlines Flight 611
Evidence

AI 182

(Forward Cargo Door)

PA103

(Forward Cargo Door)

UAL 811

(Forward Cargo Door)

TWA 800

(Forward Cargo Door)

China Airlines Flight 611

(Aft Cargo Door)

Boeing 747 Yes Yes Yes Yes  Yes
Early model -100 or -200  Yes Yes Yes Yes  Yes 
Overpressure relief door(s) in forward cargo door open/jammed Maybe Yes Yes Yes  Missing in Aft Cargo Door
Sudden airframe breakup in flight (partial or total) Yes Yes Yes Yes  Yes 
Breakup occurs amidships Yes Yes Yes Yes No, aft of wing. 
High flight time (over 55,000 flight hours) No Yes Yes Yes  Yes 
Aged airframe (over 18 years of service) No Yes Yes Yes  Yes 
Previous maintenance problems with forward cargo door Yes Maybe Yes Maybe Unknown 
Initial event within an hour after takeoff No Yes Yes Yes   Yes
Initial event at about 300 knots while proceeding normally in all parameters Yes Yes Yes Yes  Yes 
Initial event has unusual radar contacts Maybe Yes Yes Yes   Yes
Initial event involves hull rupture in or near forward cargo door area Yes Yes Yes Yes  In or near aft cargo door
Initial event starts with sudden sound Yes Yes Yes Yes Yes 
Initial event sound is loud Yes Yes Yes Yes No 
Initial event sound is audible to humans Yes Yes Yes Yes Yes 
Initial event followed immediately by abrupt power cut to data recorder Yes Yes Yes Yes No, FDR cut first, then CVR power
Initial event sound matched to explosion of bomb sound No No No No No 
  AI 182 PA103 UAL 811 TWA 800 China Airlines Flight 611
Initial event sound matched to explosive decompression sound in wide body airliner Yes Yes Yes Yes Yes, Rapid Decompression 
Torn off skin on fuselage above forward cargo door area Yes Yes Yes Yes Yes for aft door 
Unusual paint smears on and above forward cargo door Maybe Maybe Yes Yes Unknown 
Evidence of explosion in forward cargo compartment Yes Yes Yes Yes Unknown in aft 
Foreign object damage to engine or cowling of engine number three Yes Yes Yes Yes Unknown 
Fire/soot in engine number three

Maybe

Yes

Yes

Yes
  Unknown
Foreign object damage to engine or cowling of engine number four

Yes

Yes

Yes

Yes
 Unknown
Right wing leading edge damaged in flight Yes Maybe Yes Maybe Unknown 
Vertical stabilizer damaged in flight Yes Yes Yes Maybe Yes 
  AI 182 PA103 UAL 811 TWA 800 China Airlines Flight 611 
Right horizontal stabilizer damaged in flight

Yes

Yes

Yes

Yes
 Unknown
More severe inflight damage on starboard side than port side

Yes

Yes

Yes

Yes
 Unknown
Port side relatively undamaged by inflight debris

Yes

Yes

Yes

Yes
 Unknown
Vertical fuselage tear lines just aft or forward of the forward cargo door

Yes

Yes

Yes

Yes
 Yes for aft cargo door
Fracture/tear/rupture at a midspan latch of forward cargo door

Maybe

Yes

Yes

Yes
 Unknown
Midspan latching status of forward cargo door reported as latched

No

No

No

No
 Unknown
Airworthiness Directive 88-12-04 implemented (stronger lock sectors)

No

No

No

Yes
 Unknown
Outwardly peeled skin on upper forward fuselage

Yes

Yes

Yes

Yes
 Unknown
Rectangular shape of shattered area around forward cargo door

Yes

Yes

Yes

Yes
 Unknown
Forward cargo door fractured in two longitudinally

Yes

Yes

Yes

Maybe
 Yes for aft cargo door
Status of aft cargo door as intact and latched Yes Yes Yes Maybe No 
  AI 182 PA103 UAL 811 TWA 800 China Airlines Flight 611 
Passengers suffered decompression type injuries Yes Yes Yes Yes Unknown 
At least nine missing and never recovered passenger bodies Yes Yes Yes Yes Yes 
Wreckage debris field in two main areas, forward and aft sections of aircraft

Yes

Yes

No

Yes
 Yes
Initial official opinion of probable cause as bomb explosion.

Yes

Yes

Yes

Yes
 No and considered
Initial official determination modified from bomb explosion

Yes

Yes

Yes

Yes
 No
  AI 182 PA103 UAL 811 TWA 800 China Airlines Flight 611 
Structural failure considered for probable cause

Yes

Yes

Yes

Yes
  Yes
Inadvertently opened forward cargo door considered for probable cause

Yes

No

Yes

Yes
 Yes for aft cargo door
Official probable cause as bomb explosion

Yes

Yes

 No

No
 Unknown
Official probable cause as 'improvised explosive device'

No

Yes

No

No
 Unknown
Official probable cause as explosion by unstated cause

Yes

No

No

No
 Unknown
Official probable cause as explosion in center fuel tank with unknown ignition source No No No Yes Unknown 
Official probable cause as improper latching of forward cargo door No No Yes No Unknown 
Official probable cause as switch /wiring inadvertently opening forward cargo door

No

No

Yes

No
 Unknown
Significant Direct and Tangible Evidence Obtained for Four B747 Breakups in Flight

AI 182

PA103

UAL 811

TWA 800
 China Airlines Flight 611
   


Contents Cargo Door Website
Page 2 Details on Accidents
Press Kit

barry@corazon.com Email author here.


Similar Crash Pattern:
The Type Airplane
The Damage Start Location

The Radar Blips
The Sudden Loud Sounds on CVR
The Abrupt Power Cuts to FDR
The Fodded Engines
The Inflight Damage

The Missing Bodies
Same Cut Point Torn Off Noses
The Wreckage Plots
More Similarities

The Red Herring: Bomb!
Similar Crash Cause:
Mechanical Malfunction:
Inadvertent Rupture/Opening of the Forward Cargo Door in Flight
Probably Caused by Wiring/Electrical Fault


© 1996 1997 1998 1999, 2000, 2001, 2002, 2003, 2004 through 2010 John Barry Smith All Rights Reserved
(Not affiliated with the National Transportation Safety Board or any airline, manufacturer, legal firm, government agency, or independent safety group.)


Additional Details on Accidents includes AARs, photos, text, drawings, and related accidents, Air India 182, PA 103, UAL 811, and TWA 800


Background and Reference


Newer Page Reasoning behind hull rupture door opening
Introduction

Introduction Photograph
Introduction Page
reconstructmatches.html Reconstruction pictures/drawings of AI 182, PA 103, UAL 811, and TWA 800
reasoning.html Reasoning behind cargo door hypothesis
Boeing 747.html Basic Boeing 747 information.
747-121dimensions.html Drawing of Boeing 747-121
747cargo door and nose Pictures and drawings of cargo door and nose of Boeing 747
747crashes.html List of Boeing 747 crashes.
cargodoorfaraway.html Forward cargo door far, medium and close up photo.
crashchart0.html Chart of three Boeing 747 crashes and similarities presenting a pattern.
crashchart1.html Chart of three different Boeing 747 crashes/incidents and similarities.
800summary TWA Flight 800 ,UAL Flight 811, Pan Am Flight 103, Air India Flight 182 Summaries and explanations.
variousdooraccidents.html Accounts of various cargo door accidents/incidents.
forwardcargodoorpict.html Contents of links to door on site to show latch pins, openings, hinge, seal, and lock sectors.
747passdoor.html 747 plug type passenger door failed
Why Does Door Rupture/Open?
Door Goes; Nose Goes? When door ruptures, how and why nose comes off.
Press Kit


Cargo Door Opening/Rupture Event 1985
Boeing 747-237B, Air India Flight 182

AI182essentials.html Extracts from Canadian report, Boeing 747-237B. Explanations of sudden sound, decompression damage, wreckage plot, and inflight damage.
182summary.html Description of Air India Flight 182 crash with cargo door similarities.
Debriefing

AirIndiareportcontents.html To Canadian and Indian Air India Flight 182 accident report
Air India Flight 182 trial news


Cargo Door Opening/Rupture Event 1988
Boeing 747-121, Pan Am Flight 103


PA103essentials.html Extracts from AAIB accident report. Descriptions of sudden loud sound, damage location, wreckage plot, and abrupt power cut.
103radarblip1.html Pan Am Flight 103 cargo door caught on radar. Fig C-14, Boeing 747. This image matches radar plot of TWA 800.
Debriefing
Pan Am 103 Not a Bomb? Flimsy evidence for bomb now even weaker with subsequent similar accidents.
103reportcontents.html To UK Pan Am Flight 103 accident report
Pan Am Flight 103 trial news


Cargo Door Opening Event 1989
Boeing 747-122, United Airlines Flight 811


UAL811essentials.html Extracts from NTSB accident report. Descriptions of sudden loud sound, radar tracking, missing bodies, FOD engines, and sequence of destruction once door opens.
811bigholephotobetter.html Better picture of big hole that 300 knot wind enters and blows off nose of UAL 811, Boeing 747.
811page92conclusions3cause.html Revised probable cause of door opening, faulty switch.
811PS.html Popular Mechanics cover picture and story.
811picture UAL 811 cargo door hole picture
More pictures of UAL 811 cargo door hole
Debriefing

811reportcontentpage.html To UAL Flight 811 NTSB accident report


Cargo Door Opening/Rupture Event 1996
Boeing 747-131, Trans World Airways Flight 800


747crashes.html List of Boeing 747 crashes.
cargodoorfaraway.html Forward cargo door far, medium and close up photo.
pressurization1.html Aircraft pressurization theory.
aerodynamics.html Boundary layer aerodynamics.
Airworthiness Directive 79-17-02.html First Airworthiness Directive against forward cargo door.
Airworthiness Directive 88-12-04 Original AD to prevent inadvertent opening of forward cargo door, later amended by AD 89-05-54, not available, later amended by AD 90-09-06 below.
Airworthiness Directive 90-09-06 Current AD to try again to stop doors from opening when they shouldn't.
variousdooraccidents.html Accounts of various cargo door accidents/incidents.
NTSB TWA 800 rebuttal letter Letter to officials regarding wiring/cargo door explanation 16 Jan 01


Cargo Door Uncommanded Openings 1991 and 2000 Nonfatal (First instance on -400)

Difficulty Date : 10/11/00
Operator Type : Air Carrier
ATA Code : 5210
Part Name : CONTROLLER
Aircraft Manufacturer : BOEING
Aircraft Group : 747
Aircraft Model : 747422
Engine Manufacturer : PWA
Engine Group : 4056
Engine Model : PW4056
Part/Defect Location : CARGO DOOR
Part Condition : MALFUNCTIONED
Submitter Code : Carrier
Operator Desig. : UALA
Precautionary Procedure : NONE
Nature : OTHER
Stage of Flight : INSP/MAINT
District Office Region : Western/Pacific US office #29
A/C N Number : 199UA
Aircraft Serial No. : 28717

Discrepancy/Corrective Action:FWD CARGO DOOR OPENED BY ITSELF WHEN CB PUSHED IN. ON ARRIVAL, CIRCUIT BREAKERS WERE PUSHED IN, WHEN PRESSURE RELIEF DOOR HANDLE WAS OPENED THE DOOR LATCHES OPENED AND THEN THE DOOR OPENED ON ITS OWN. COULD NOT DUPLICATE PROBLEM AFTER INITIAL OPENING.


From NTSB AAR 92/02 United Airlines Flight 811

1.17.6 Uncommanded Cargo Door Opening--UAL B-747, JFK Airport
On June 13, 1991, UAL maintenance personnel were unable to electrically open the aft cargo door on a Boeing 747-222B, N152UA, at JFK Airport, Jamaica, New York. The airplane was one of two used exclusively on nonstop flights between Narita, Japan, and JFK. This particular airplane had accumulated 19,053 hours and 1,547 cycles at the time of the occurrence.
The airplane was being prepared for flight at the UAL maintenance hangar when an inspection of the circuit breaker panel revealed that the C-288 (aft cargo door) circuit breaker had popped. The circuit breaker, located in the electrical equipment bay just forward of the forward cargo compartment, was reset, and it popped again a few seconds later. A decision was made to defer further work until the airplane was repositioned at the gate for the flight. The airplane was then taxied to the gate, and work on the door resumed.
The aft cargo door was cranked open manually, the C-288 circuit breaker was reset, and it stayed in place. The door was then closed electrically and cycled a couple of times without incident. With the door closed, one of the two "cannon plug" (multiple pin) connectors was removed from the J-4 junction box located on the upper portion of the interior of the door. The wiring bundle from the junction box to the fuselage was then manipulated while readings were taken on the cannon plug pins using a volt/ohmmeter. Fluctuations in electrical resistance were noted. When the plug was reattached to the J-4 junction box, the door began to open with no activation of the electrical door open switches. The C-288 circuit breaker was pulled, and the door operation ceased. When the circuit breaker was reset, the door continued to the full open position, and the lift actuator motor continued to run for several seconds until the circuit breaker was again pulled. At this time, a flexible conduit, which covered a portion of the wiring bundle, was slid along the bundle toward the J-4 junction box, revealing several wires with insulation breaches and damage.


Cargo Door Opening/Rupture Event 2002
Boeing 747-209B, China Airlines Flight 611

Smith Table showing matches of evidence among China Airlines Flight 611, Air India Flight 182, Pan Am Flight 103, United Airlines Flight 811, and Trans World Airlines Flight 800.

PDF Smith AAR and official AAR for Air India Flight 182, Pan Am Flight 103, and United Airlines Flight 811. PDF files of Smith AARs for TWA Flight 800, Pan Am Flight 103 and Air India Flight 182 are available at http://www.planetofearth.com. These Smith AARs show in pictures and text the destruction of Boeing 747s which suffer inflight breakups of which there are now five, Air India Flight 182, Pan Am Flight 103, United Airlines Flight 811, Trans World Airlines Flight 800, and China Airlines Flight 611.


 

 


Page 2 Details on Accidents
Boeing Manufacturer of 747
http://www.ntsb.gov/ NTSB
http://www.faa.gov/avr/aai/aaihome.htm FAA
barry@johnbarrysmith.com Email author here.