# Alabama Air Case

Topics: Airline, Darden Restaurants, Statistical process control Pages: 3 (475 words) Published: February 27, 2010
1.State any business problem that the enterprise needs to resolve: Darden Restaurants needs to manage a supply-chain of highly perishable items such as seafood, over 35 countries, while managing costs and product quality. Furthermore, the company needs to ensure a strict protocol of inspection and quality assurance throughout the supply chain.

2.Briefly summarize relevant background information from the case. Darden restaurant owns popular brands such Olive Garden and Red Lobster, comprising of 1400 restaurants in the US. These are 300 million meals served annually with purchases from 35 ountries. The average shelf life of the food item is 4 days and temperature of 34 degrees must be ensured at each step of the way.

3.Describe how the enterprise dealt with its issues and their relevance The airline executives have decided to use Statistical Process Control tools to measure the airlines on-time performance and to guage how it is doing in relation to the rest of the airline industry.

The Data:
WeekLate FlightsFraction Late
120.02
240.04
3100.1
440.04
510.01
610.01
7130.13
890.09
9110.11
1000
1130.03
1240.04
1320.02
1420.02
1580.08
1620.02
1730.03
1870.07
1930.03
2020.02
2130.03
2270.07
2340.04
2430.03
2520.02
2620.02
2700
2810.01
2930.03
3040.04
120

4.Using a 95% confidence level plot the overall percentage of late flights p, and the upper and lower control limits.

p =Total Number of errors
Total Number of Sample

p=120=0.04
(100)*(30)

sigma=SQRT(((.04)*(1-.04))/100)

sigma=0.02

UCL=p + 2*.02=0.08

LCL=p - 2*.02=0

Using 95% Confidence level (z=2), we plot a control chart for the fraction of late flights for ezch week. We also superimpose the industry upper and lower control limits of .1 and .04 repectively:

The Fraction of flights late on Week 3, 7, 8 and 9 fall above the UCL of .08 for...