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Nepal Airlines jet plane choice, 4 years and infinite

Short answer

For 4-year need: annual equivalent cost A = 8.68 crore, B (using6 crore salvage at year 4) = 9.62 crore; select A. For infinite period: capitalized cost A = 72.37 crore, B = 62.98 crore; select B.

Nepal Airlines is planning to purchase a jet plane. The estimates on two types of plane under consideration are:

ProjectPlane APlane B
First investment cost25,00,00,00030,00,00,000
Annual O & M1,50,00,0001,00,00,000
Useful Life4 years6 years
Salvage value5,00,00,0006,00,00,000
MARR = 12 %
Which plane is the best one if it is believed that the plane will be used for i) 4 years and ii) infinite period?

All amounts in Rs crore (1 crore = 1,00,00,000). Both planes are cost-only alternatives, so the one with the lower equivalent annual cost (AEC) is chosen. MARR = 12%.

Factors: (A/P,12%,4) = 0.32923, (A/F,12%,4) = 0.20923; (A/P,12%,6) = 0.24323, (A/F,12%,6) = 0.12323.

(i) Service needed for 4 years

AEC(A) = 25(A/P,12%,4) − 5(A/F,12%,4) + 1.5
       = 25(0.32923) − 5(0.20923) + 1.5
       = 8.231 − 1.046 + 1.5 = 8.685  crore/yr

Plane B has a 6-year life, so for a 4-year need its value at year 4 is required. It is not given, so assume the quoted salvage value of Rs 6 crore is what it realises at year 4 (the only figure available):

AEC(B, 4 yr) = 30(A/P,12%,4) − 6(A/F,12%,4) + 1.0
             = 9.877 − 1.255 + 1.0 = 9.622  crore/yr

AEC(A) = 8.68 < AEC(B) = 9.62, so Plane A is selected for 4 years.

Sensitivity of the assumption: B would win only if its year-4 market value exceeds about Rs 10.5 crore (for example, Rs 14 crore from straight-line decline of 30 → 6 gives AEC = 7.95). On the given data, A is chosen.

(ii) Service needed for an infinite period

Each plane is replaced by an identical one at the end of its life (repeatability), so capitalized equivalent cost CE = AEC / i.

AEC(B, 6 yr) = 30(A/P,12%,6) − 6(A/F,12%,6) + 1.0
             = 7.297 − 0.739 + 1.0 = 7.557  crore/yr

CE(A) = 8.685 / 0.12 = 72.37 crore
CE(B) = 7.557 / 0.12 = 62.98 crore
PlaneAEC (crore/yr)Capitalized cost (crore)
A (4 yr)8.68572.37
B (6 yr)7.55762.98

Answer: (i) For 4 years choose Plane A (AEC 8.68 vs 9.62 crore/yr). (ii) For an infinite period choose Plane B (AEC 7.56 vs 8.68 crore/yr; capitalized cost 63.0 vs 72.4 crore).

✓ Answer checked by Claude Opus 5.5 (high effort)

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