Question

Prompt:

An airline operates a short-haul passenger jet with the following parameters:

​

• Empty weight: 95,000 lb
   

• Maximum take-off weight: 140,000 lb
   

• Current range: 900 miles
   

• Fuel capacity: 6,875 gallons of Jet-A
   

• Fuel consumption rate: ~0.50 lb/(lbf·h)
   

• Engine thrust: 28,000 lbf per engine (2 engines)
   

• Cruise speed: Mach 0.78 (≈515 mph)
   

• Cruise altitude: 35,000 ft
   

• Operating cost: $700,000 budget for retrofits
   

Your task is to modify the aircraft to:

​

1. Reduce fuel consumption by 10%
    

2. Extend the aircraft’s range from 900 to 1,100 miles
    

3. Stay under 140,000 lb take-off weight
    

4. Stay within the $700,000 upgrade budget
    

You may change:

​

• Engine (not thrust rating)
   

• Fuel type
   

• Aerodynamics
   

• Fuel tank capacity (add internal tanks only)
   

• Interior or cargo weight
   

• Avionics or software
   

Show all calculations and justify your design.