Why do helicopters make a ‘Chop Chop Chop’ sound when their rotors are spinning at a constant rate through the air?
The pressure difference between the air flowing over and under the rotor blade forms a vortex at the blade tip (all wings do this). When a blade encounters the vortex from another blade, it slaps into the blade. Like a jetski hitting the wake of another jetski.
The Short Answer
The pressure difference between the air flowing over and under the rotor blade forms a vortex at the blade tip (all wings do this). When a blade encounters the vortex from another blade, it slaps into the blade. Like a jetski hitting the wake of another jetski. The more the blade is loaded, the stronger the vortex, the louder the sound. Which gives the Huey, with its two large, heavily loaded blades, that distinctive "whop, whop" sound.
Analysis
Key Concepts: Blade, vortex, another
This explanation focuses on blade, vortex, another and spans 77 words across 5 sentences. The depth is typical for Animals questions (category average: 68 words), striking a balance between accessibility and completeness.
What This Answer Covers
The explanation opens with: “The pressure difference between the air flowing over and under the rotor blade forms a vortex at the blade tip (all wing” It then elaboratesultimately building toward a complete picture across 5 connected points.
How This Compares in Animals
Ranked #178 of 500 Animals questions by answer depth (top 36%). This falls in the detailed tier — above average depth. The explanation goes beyond surface-level but keeps things accessible.
Frequently Asked Questions
Is there a simple explanation for why helicopters make a 'chop chop chop' sound when their rotors are spinning at a constant rate through the air?
The pressure difference between the air flowing over and under the rotor blade forms a vortex at the blade tip (all wings do this). When a blade encounters the vortex from another blade, it slaps into the blade. Like a jetski hitting the wake of…
How detailed is this explanation compared to similar Animals questions?
This is an above-average answer at 77 words, ranked #178 of 500 Animals questions by depth. The key concepts covered are blade, vortex, another.
What approach does this answer take to explain helicopters make a 'chop chop chop' sound when their rotors ?
The explanation uses direct explanation across 77 words. It is categorized under Animals and addresses the question through 1 analytical lens.