Statistical quality control, airline operations. Jetrans Airlines operates daily round-trip flights on the London-Vancouver route using a

Question:

Statistical quality control, airline operations. Jetrans Airlines operates daily round-trip flights on the London-Vancouver route using a fleet of three 747s: the Spirit of Birmingham, the Spirit of Glasgow, and the Spirit of Manchester. The budgeted quantity of fuel for each round-trip flight is the 12-month mean (average) round-trip fuel consumption of 200 litre- units, with a standard deviation of 20 litre-units. A litre-unit is 1,000 litres. Using a statistical quality control (SQC) approach, Shirley Watson, the Jetrans opera- tions manager, investigates any round trip with fuel consumption that is greater than two standard deviations from the mean. In October, Watson receives the following report for round-trip fuel consumption for the three planes on the London-Vancouver route: image text in transcribed

REQUIRED 1. Using the +2o rule, what variance-investigation decisions would be made?
2. Present SQC charts for round-trip fuel usage for each of the three 747s in October. What inferences can you draw from the charts?
3. Some managers propose that Jetrans Airlines present its SQC charts in monetary terms rather than in physical-quantity terms (litre-units). What are the advantages and disadvantages of using monetary fuel costs rather than litre-units in the SQC charts?LO1