If an airplane is consuming 9.5 gallons of fuel per hour at a cruising altitude of 6,000 feet and the groundspeed is 135 knots, how much fuel is required to travel 490 NM?

To determine how much fuel is required to travel 490 nautical miles (NM) at a groundspeed of 135 knots, it's essential to first calculate the time taken for the journey.

1. Calculate Travel Time: The time (in hours) to cover a specific distance can be determined using the formula:

[

\text{Time} = \frac{\text{Distance}}{\text{Groundspeed}}

]

Substituting the values:

[

\text{Time} = \frac{490\ \text{NM}}{135\ \text{knots}} \approx 3.63\ \text{hours}

]

2. Calculate Fuel Consumption: From the problem, the airplane consumes 9.5 gallons of fuel per hour. To find the total fuel required for the 3.63 hours of travel, multiply the fuel consumption rate by the travel time:

[

\text{Fuel Required} = \text{Rate of Fuel Consumption} \times \text{Time}

]

Substituting the values:

[

\text{Fuel Required} = 9.5\ \text{gallons/hour