Pertinent to

 TWA800?

We are all living under the same skies, but we all have different horizons. Konrad Adenauer

747 CARGO DOORS THAT OPEN MYSTERIOUSLY

and This STORY CONTINUES      HERE   -   and with it, the plot thickens
Subject:  747 and cargo door and wiring and CB, go together...

The story below is very very scary knowing what we know about forward cargo doors opening in flight from electrical causes. If that CB had been pushed in  (why was it out?) during flight, that forward cargo door would have ruptured/opened with known catastrophic results. What is a 'controller' and what 'malfunctioned'?

 UAL, above incident airline and well familiar with UAL 811, had habit of pulling door CB out and were told to stop, order 8300.10 below. They are apparently still pulling the door CB and it may have saved their ass.

Please use whatever influence you have in safety to pursue the shorted wiring/forward cargo door rupture/explosive decompression/inflight break-up explanation for 747 accidents. Do something.

Sincerely,

Barry

www.corazon.com

 

Difficulty Date : 10/11/00

Operator Type : Air Carrier

ATA Code : 5210

Part Name : CONTROLLER

Aircraft Manufacturer : BOEING

Aircraft Group : 747

Aircraft Model : 747-422

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. It is possible to fly without motors, but not without knowledge and skill. Wilbur Wright

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.

ORDER: 8300.10

APPENDIX: 4

BULLETIN TYPE: Flight Standards Information Bulletin (FSIB)

for Airworthiness (FSAW)

BULLETIN NUMBER: FSAW 93-50

BULLETIN TITLE: Inappropriate Use of Circuit Breakers

During B-747 Lower Lobe Cargo Door Operation

EFFECTIVE DATE: 06-02-94

---------------------------------------------------------------

1. SUBJECT. This FSIB informs inspectors of unsafe procedures being used by some operators to close and lock the lower lobe cargo doors of the Boeing 747 (B-747) series aircraft.

2. BACKGROUND.

A. This bulletin was developed after an inquiry by a foreign airworthiness authority into the special procedures used by a specific operator to close and lock the lower lobe cargo doors of B-747 series aircraft. The special procedure included in the operator's maintenance manual called for manual tripping of the cargo door control circuit breakers and the section 2 ground handling bus circuit breaker in order to further remove the possibility of power being applied accidentally to the cargo door control circuitry.

B. The manual tripping of the circuit breakers in special cargo door lock procedures is unnecessary and decreases the reliability of the circuit breakers to perform their intended function.

Frequent switching of the breakers could cause them to trip before the point of rated voltage or not to trip at all. Both cases could have adverse effects (such as the following) in relation to the safe operation of the cargo doors:

(1) Circuit breakers that trip before the point of rated voltage would cause increased manual operation of the cargo doors.

(2) Manual operation could introduce additional failure conditions, such as out-of-sequence operation and overdriving of the cargo door mechanisms.

(3) Service history has shown that manual operation of the cargo doors is more prone to cause damage; for example, the failure of a breaker to trip at the point of rated voltage could lead to failed components and fire.

2 C. The revision to the B-747 cargo door lock sectors warning system, in airplanes compliant with Airworthiness Directive (AD)90-09-06, provides an increased level of integrity so that manual tripping of the circuit breakers is not necessary to prevent the possibility of an uncommanded opening of the cargo doors.

Furthermore, power to the cargo door is automatically removed by the Master Latch Lock System upon first motion of the Master Latch Lock Switch away from the fully unlocked position.

3. ACTION. Principal maintenance inspectors (PMI) having certificate management responsibilities for operators of Boeing 747 series aircraft should ensure that this information is brought to the attention of their respective operators. Any operators using this procedure should be discouraged from its continued use.

4. INQUIRIES. This FSIB was developed by SEA.AEG. Any questions regarding this information should be directed to AFS-510 at (703) 661-0333, extension 5018.

5. EXPIRATION. This FSIB will expire on 05-31-95.

/s/ Edgar C. Fell

 

Another case in point

Difficulty Date : 6/10/00

Operator Type : Air Carrier

ATA Code : 2400

Part Name : HARNESS

Aircraft Manufacturer : BOEING

Aircraft Group : 747

Aircraft Model : 747212B

Part/Defect Location : FUSELAGE

Part Condition : ARCED

Submitter Code : Carrier

Operator Desig. : IPXA

Precautionary Procedure : NONE

Nature : OTHER

Stage of Flight : INSP/MAINT

District Office Region : Southern US office #01

A/C N Number : 521UP

Aircraft Serial No. : 21944

Discrepancy/Corrective Action: INSPECTION TYPE: C, FWD CARGO HOLD -

CABLE LOOM PASSING THROUGH FRAME AT BS 520, RBL 24 SHOWS EVIDENCE OF ARCING. ACCOMPLISHED PER QUERY NOTE 35/2000 WHICH ASKS FOR WIRES TO BE REMOVED AS SYSTEM IS INACTIVE. WIRES REMOVED FROM CB C914 IN P14 PANEL TO RELAY R175 IN PANEL P86, AT FWD CARGO DOOR PER WDM 24-51-72.

 

Difficulty Date : 2/18/01

Operator Type : Air Carrier

ATA Code : 5230

Part Name : DOOR

Aircraft Manufacturer : BOEING

Aircraft Group : 747

Aircraft Model : 747-123F

Part/Defect Location : AFT CARGO DOOR

Part Condition : UNSECURE

Submitter Code : Carrier

Operator Desig. : IPXA

Precautionary Procedure : UNSCHED LANDING

Nature : WARNING INDICATION

Stage of Flight : CLIMB

District Office Region : Southern US office #01

A/C N Number : 672UP

Aircraft Serial No. : 20324

Discrepancy/Corrective Action: INSPECTION TYPE: N/A, ATB-

UNABLE TO PRESSURIZE IN AUTO OR MANUAL MODE AFTER TAKEOFF. A/C PRESSURIZED ON LANDING. *S/D* SECURED AFT LOWER CARGO DOOR LATCH LOCK HANDLE AND VENT DOORS PERFORMED CARGO DOOR TEST, NO FAULTS NOTED.

The STORY CONTINUES      HERE   -   and the plot thickens
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The fact that man knows right from wrong proves his intellectual superiority to other creatures; but the fact that he can do wrong proves his moral inferiority to any creature that cannot. Mark Twain: _What is Man?_, 1906