Product A is assembled from the three sub assemblies B, C, D, and component E. Subassembly B is assembled from the three assemblies F, G, and H. Subassembly C is assembled from components J and K and subassembly L. Subassembly D is assembled from component M and subassembly N.
• Subassembly F is assembled from P-Q-R
• Subassembly G is assembled from S-T
• Subassembly H is assembled from W-X
• Subassembly L is assembled from Y-Z
• Subassembly N is assembled from W-aa
• Subassembly T is assembled from Y-W-bb Now consider the following:
• It takes four days to produce or assemble B, D, F, L, and W.
• It takes four days to produce or assemble A, E, G, H, K, and N.
• It takes four days to produce or assemble C, J, M, Q, S, and T.
• It takes four days to produce or assemble P, R, X, Y, Z, aa, and bb.
a. Design a product structure tree to show how parts come together for completion of the product.
b. Calculate the earliest time to complete the work if all parts are to be produced.
c. Calculate the time needed for complete if the production of J, E, and T has been under-estimated by four days, three days, and one day, respectively.
d. Assume all parts except A, E, F, Z, Y, and N are held in inventory. How long will it take to produce the product? Explain your answer.
e. Assume all parts except A, B, H, L, Q, and N are held in inventory. How long will it take to produce the product? Explain your answer.
f. Assume no inventory of subassemblies or components is held. Construct a Gantt chart showing the last possible starting and finishing time for all work to ensure that completion of the final product is not delayed.