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Starter: Straits Wings: Singapore to Bangkok

You run the case. Read the prompt, answer questions from the notes below, and share data only when the candidate asks for it or gets stuck. Score at the end.

Case timer

00:00

Target length:

1. Read the prompt aloud

Read it slowly, then pause. Let the candidate ask questions before they structure.

First, estimate how many passengers fly between Singapore and Bangkok each year. Then: Straits Wings, a low-cost airline, wants to add two daily round trips (four flights a day). Is it worth it?

Format note: Difficulty: Starter. Format: market-sizing opener, then a business question. Industry: Airlines and travel. Region: Singapore and Thailand. Interview length: about 25 minutes. The company is fictional and all figures are illustrative.

2. Answers to clarifying questions

Give these answers only if the candidate asks. If they ask something not listed, give a sensible answer or say it does not matter here.

If asked: Both directions, and only direct flights?
Answer: Yes, both directions, direct flights only.
If asked: How many flights and how big?
Answer: About 25 flights a day each way, around 180 seats each, about 85 percent full.
If asked: For the business question, what are the fare, costs, and expected load?
Answer: Average fare SGD 120 one way; each flight costs about SGD 16,000 to operate; we expect about 80 percent of seats filled.

3. The hypothesis a strong candidate states

Listen for an early, testable guess like this one. It does not need to match word for word.

This is a busy route, so the market is a few million passengers a year. For a new entrant, my hypothesis is that the extra flights work only if they fill well above three quarters of seats.

4. A model structure

Compare the candidate's structure with this one. A different split can be just as good if it is clean and fits the problem.

Size the route, then test one flight's economics
- Flights x seats x load factor x days
- Key: Revenue and profit per flight
- Break-even load factor

5. The working, step by step

Each step shows how a strong candidate works it out. Share a new fact from it only when the candidate asks or is stuck, and let them do the math: the result in the dark box is what they should reach.

Step 1: Passengers a year
What a strong candidate does: 25 flights each way, 180 seats, 85 percent full, 365 days.
Passengers a year: 25 × 2 × 180 × 0.85 × 365 = 2,792,250
Step 2: Revenue per flight
What a strong candidate does: 180 seats, 80 percent full, SGD 120 each.
Revenue per flight (SGD): 180 × 0.8 × 120 = 17,280
Step 3: Profit per flight
What a strong candidate does: Minus SGD 16,000 of cost.
Profit per flight (SGD): 180 × 0.8 × 120 - 16,000 = 1,280
Step 4: Yearly profit
What a strong candidate does: Four flights a day for a year.
Yearly profit (SGD): 4 × 365 × (180 × 0.8 × 120 - 16,000) = 1,868,800
Step 5: Break-even load factor
What a strong candidate does: Cost divided by revenue from a full flight.
Break-even load factor (%): 16,000 ÷ (180 × 120) × 100 = 74.07
Step 6: Curveball: rivals cut fares
What a strong candidate does: Interviewer: "The largest rival responds by cutting its fare to SGD 100, and we must match." Profit per flight at 80 percent full:
Profit per flight at SGD 100 (SGD): 180 × 0.8 × 100 - 16,000 = -1,600
Step 7: New break-even
What a strong candidate does: At SGD 100, the flight must be this full to break even.
Break-even load factor at SGD 100 (%): 16,000 ÷ (180 × 100) × 100 = 88.89

The recommendation to listen for

At the end, say: "The CEO walks in. What is your recommendation?"

The route carries about 2.8 million passengers a year, and the new flights are only narrowly worth adding. First, at SGD 120 and 80 percent full, four daily flights earn about SGD 1.9 million a year. Second, break-even is about 74 percent full, so there is only a small cushion. Third, if rivals cut fares to SGD 100, each flight loses about SGD 1,600 and would need to be about 89 percent full. Start with one daily round trip at times rivals do not serve well, and add the second only if load factors stay above 80 percent at current fares.

Risks a strong answer names: A fare war on a busy route; Airport slot costs at popular times.

Next steps: Check which departure times are least served; Sell the first month of seats before committing the second round trip.

Strong versus weak

A strong answer

Sized the route cleanly, then found the break-even load factor and showed how a fare cut changes it.

A weak answer

Said the route is big so there is room for more flights, without checking whether each flight makes money.

Score the candidate

Score each criterion from 1 to 5. A 2 or a 4 sits between the descriptions.

This case has no exhibit. Score Exhibit reading on how the candidate used the data you gave them: did they pick out the number that matters and say what it means?

Structuring

1: No clear structure, or a memorized framework that does not fit the problem.
3: A sensible structure, but with some overlap, a gap, or no clear priority.
5: A structure built for this problem, with no overlap and no gaps, a stated hypothesis, and a clear first step.

Math

1: Frequent errors, no units, or needed heavy help to finish.
3: Right answers but slow or messy working, or one error caught late.
5: Accurate and clearly narrated, with units, a sense check, and what the number means.

Exhibit reading

1: Read the chart aloud without finding the number that matters.
3: Found the key number but gave only part of the so-what.
5: Pulled the right number quickly and said what it means for the case.

Synthesis

1: Summarized what was done, with no clear answer.
3: Gave an answer, but with weak reasons or no next step.
5: Answer first, then two or three reasons with numbers, the main risk, and next steps.

Communication

1: Hard to follow: long silences, no signposting.
3: Clear most of the time, with some rambling.
5: Calm and concise, signposted each step, and checked in with the interviewer.

Total

0 out of 25

Score all five criteria to see the band and the feedback template.