Which helicopter has the highest noise exposure level?

Which helicopter has the highest noise exposure level?

• A. UH-60
• B. AH-64
• C. LH-72
• D. CH-47

Answer: (D)

Noise exposure level in helicopters comes from both rotor noise and engine noise, and the amount of sound energy produced depends on rotor system size and how many rotors are active. The CH-47 Chinook uses two large main rotors, each a major source of aerodynamic noise. Having two such sources, along with substantial engine power for heavy-lift operations, adds up to more cumulative sound energy than a single-rotor helicopter. The UH-60 and AH-64 each have one main rotor, and the LH-72 is a lighter helicopter with smaller rotors and lower power requirements, so their noise exposure is generally lower. With its dual large rotors and high-power operation, the CH-47 tends to produce the highest noise exposure level.

Noise exposure level in helicopters comes from both rotor noise and engine noise, and the amount of sound energy produced depends on rotor system size and how many rotors are active. The CH-47 Chinook uses two large main rotors, each a major source of aerodynamic noise. Having two such sources, along with substantial engine power for heavy-lift operations, adds up to more cumulative sound energy than a single-rotor helicopter. The UH-60 and AH-64 each have one main rotor, and the LH-72 is a lighter helicopter with smaller rotors and lower power requirements, so their noise exposure is generally lower. With its dual large rotors and high-power operation, the CH-47 tends to produce the highest noise exposure level.