CARGO DOOR’S DEPRESSOR SEAL
Depressor Seal
Damaged Depressor Seal
DAMAGED DEPRESSOR SEAL
Damaged Depressor Seal
Background
Six Sigma is data – driven business process optimization methodology which aims to reduce variation, elimination non-value added activities and significantly improve process quality.
How does it work ?
Define What is important to the organization ?8-Blocker, Fishbone, CTQ, Process Flow
MeasureHow much can the existing process improve ?
Capability analysis
AnalyzeWhat are the critical factors ?
Hypothesis testing, Regression
ImproveHow to reduce variation, time, cost, defects ?
DOE, Simulation
ControlHow to maintain improvement ?
SPC
(DMAIC)
Y
Xs
Y
Y
YX
Y = f(X)
DEFINE & MEASURE
Project DefinitionProject Definition
Objective Reduce depressor seal damage (DSD) by more than
50%Defect Definition FWD & AFT Cargo Doors Depressor seal damage
(DSD)Benefits Reduce maintenance repair cost Reduce flight delays Minimize operation interruptionsConstraints Non-availability of detail data regarding the damage Non-availability of maintenance repair cost
Team Members Saad Nujaim Adel Sait Mohammad Fayoumi Khaild al ghomari
Master Black Belt Saad NujaimProcess Sponsor GS, MD- GS Strategic Unit
Team MembersTeam Members
Hardness of depressor seal
Guiders set up of Hi-Loaderweather
Condition of container
Temperature
.
Training DPU
Supervision
Materials Environment Methods
DepressorSeal
Damage (DSD)
Manpower Machine
Position Hi-Loaders
Fatigue
License
Light
Measurements
Shipment Size
A/C Door size
Rush Operation
Using of stoppers inCargo compartment
A/F Protection Guiders
Condition of stoppers in a/c Cargo comprtment
Different natis
Qualification
Cause and EffectCause and Effect
Check for External &
Internal Dep. Seal Damage
Offload Containers from CGO
compartment to H/L
Offload Containers from H/L to Transporter
Wait for Loading
Load Containers from transporter to
H/L
Load Containers from H/L to CGO
Comartment Stow Safety Rails Close CGO door
Hi-loader positioned properlyOffloadLoad
Existing Loading/ Offloading Existing Loading/ Offloading ProcessProcess
Descriptive Statistics for all DSDDescriptive Statistics for all DSD (2001 – 1st Qtr of 2008)
Process Capability
Run Chart (2001 – 1st Qtr of 2008)
Upper Specification Limit (LSL) = 2 dsd/qrt N (LT) = 28
N (ST) = 6
Z (ST) = [ USL - Avg DSD (ST) ] STDEV(ST) Z (LT) = [ USL - Avg DSD (LT) ] STDEV(LT)
Avg DSD (ST) = 1.17 Avg DSD (LT) = 3.17 STDEV (ST) = 0.98 STDEV (LT) = 2.59
** Z (ST) = [ 2 – 1.17 ] 0.98 = 0.85 ** Z (LT) = [ 2 – 3.71] 2.59 = - 0.66
Z (SHIFT) = Z(ST) – Z(LT) = 0.85 + 0.66 = 1.51
Calculation of Z-ST & Z-LT
Zst =0.85Zlt =- 0.66Zshift = Zst - Zlt = 0.85+0.66 =1.51
Control is fineImpove factoryor technology
World class
Need better controlTechnology is fine
Poor controlPoor technology
3.0
1.5
0.0
Con
trol
(Zsh
ift)
0.0 3.0 6.0 Technology
(Zst)
Where we are now
Goal
Control Vs Technology
ANALYSIS
86 % of DSD is related to B-747 ,while 14 % is related to other fleet type.
Depressor Seal Damage Based on A/C Type
53% OF DSD took place in Jeddah and Riyadh stations
Depressor Seal Damage by Station
Variables R-value Interpretations
(No of DSD) and ( No of Revenue Departure For All Fleet) 0.277 Weak relationship
(No of DSD) and ( No of Revenue Departure Form JED&RUH Stations) 0.844 Strong
relationship
(No of DSD) and ( No of Revenue Departure For B-747) 0.698 Good relationship
Determination of the existence relationship between the number of DSD and some other variables is measured by the value of the correlation coefficient “R”. The Correlation Analysis and its “R” value is shown in the table below:
Based on the above table , it is clear that the total number of DSD is linearly correlated to JED & RUH operation and B-747 fleet.
Note: Data Source :ARP-TSV
Relationship Between DSD And Other Variables
One of the major causes of DSD incident is loading and off loading operation on the A/C. B-747 A/C and B-777 A/C are very identical in terms of :1- Loading / off-loading operation2- Shipment types and size (ULD’S & Pallets)3- Equipment used for loading/off-loading operation.
Factor B-747 B-777 Interpretations
Hardness of DS MAT.7075-T6.Thichness0.05
MAT.2024-T42.Thichness0.063
Not significat,T6 is harder
Door size FW& AFT (264 cm by 168 cm)
FW (269 cm by 170 cm). AFT (A-J 177.8 Cm by 170.2//
OTHERS 269.2 Cm by 170Cm)
B-777 is bigger by 5 cm X 2 cm except for A-J
AFT door
Protection guide fitted in A/C Not Available Available
Help offloading Operation
Drive Power Unit
PDV2101(1,5,3,6).UNT2218(0).DRV2100(0,1,1,2).DV2300(3,0,4,3)
KUNT251(3,5,3,2).KUNT252(0,0,0,1).
KUNT250(0)
Both reliable, not a sensitive
cause*
Analysis of DSD Causes
* Components Removals for years 2003,2004,2005,2006,2007 data Source :ARP-TSV
Question :- Does the operation volume of A/C B-747 and A/C B777 is significantly Different ?Test of Hypothesis is used to compare the mean of B-747 NO. revenue dept and the mean of B-777 NO. revenue dept.Analysis of VarianceSource DF SS MS F PFactor 1 47383681 47383681 60.17 0.000Error 54 42525739 787514Total 55 89909420 Individual 95% CIs For Mean Based on Pooled StDevLevel N Mean StDev -------+---------+---------+---------B-747ALL 28 4086.8 851.0 (---*----) B-777 28 5926.5 922.4 (----*---) -------+---------+---------+---------Pooled St Dev = 887.4 4200 4900 5600
Answer : YesBecause the P-value = 0.000 , < 0.05 , we conclude that there is a statisticaldifference between the two means and the mean of B-777 NO. revenue dep. is higher.
Operation Volume Analysis
Following observations were made during the inspections performed in Jeddah and Dhaka (may2008) stations:No adjustment for Hi-loader’s protection guiders was made during loading and off-loading operation.
Analysis of Loading/offloading and Hi-loader Operation
Analysis of Loading/offloading and Hi-loader Operation
The operator stands on the right side of A/C door.
A lot of damaged ULDs were used.
Analysis of Loading/offloading and Hi-loader Operation
Some of heavy ULDs were handled by the operator alone.
Inadequate supervision
33 % OF DSD was located on the left side of A/C CGO doors, while 14 % of DSD was On right side of A/C CGO doors.
Depressor Seal Damage By Door Location
The analysis revealed that:1- Hi-loader’s protection guiderssetting is considered as
the major cause of DSD.
2- Damaged and heavy ULDs are another cause of DSD in the absence of proper setting of Hi-loader’s protection guiders and the operator stand alone on the right side of A/C cargo door.
Conclusion
Conclusion
3- Cargo door of B-777 has less DSD due to :
A- Bigger door size in width.
B- It has protection guide fitted in A/C’s cargo door (help in offloading).
B-777 B-747
RECOMMENDATIONS
1. Hi-loader protection guiders must be adjusted within A/C Cargo door width.
2. Damaged ULD’S should not to be used.
3. ULD’S weight must be controlled to avoid loading of heavy ULD’S.
RECOMMENDATIONS4. Assistance must be requested by the operator in case of facing stuck/heavy ULD’s.
5. Damaged ULD’s should not be loaded side door.
6. Any failure of PDU should be reported by the operator.
IMPROVE & CONTROL
Check for External &
Internal Dep. Seal Damage
Offload Containers from CGO
compartment to H/L
Offload Containers from
H/L to Transporter
Wait for Loading
Load Containers from transporter
to H/L
Load Containers from H/L to CGO
Comartment Stow Safety Rails Close CGO door
heavy container
stuck/damaged?
Hi-loader positioned properly
NO
YES
Call for assistance
/fix
Heavy containers
stuck/damaged?
NO
YES 1)Call for assistance/fix2) don’t place on door
sides
OffloadLoad
Adjust the protection
guiders
IMPROVED Loading/ Offloading ProcessLoading/ Offloading Process
Depressor Seal damaged Trend
Process Fixes & Control
Causes of Variation
- The Adjustment of Hi-loader’s protection guiders was not performed
-A lot of ULD’S were damaged.
- Inadequate Supervision.
Process Fix -Review & study the processes of loading and offloading.
-Update GSPM to include the recommendations.
-To enhance safety awareness by explaining correct practices to the concerned staff.
- GS established licensing & training programs.
Control System
- Monitor the processes of loading and offloading.
- Perform the random inspection.
- Monitor DSD trend.
Project Closure
Financial Eliminate the maintenance repair cost Eliminate any related cost to operation interruption and flight delays
Operation Minimize operation interruption Minimize unexpected flight delays Improve A/C safety.
Implementation of project recommendations will yield the following :-