Whistle Rocket Part 2

I bought a hand launched “whistling rocket” from the nearby WalMart.
The entire rocket is made of foam except for the plastic whistle near the nose of the rocket. I don’t really know acoustic science, I’ll do my best to explain how it works.

The launcher is an air plunger made of heavy cardboard. The rocket is socketed onto the (green plastic, lower left) open tube on the hand launcher. The outside plunger is pulled back to fill the chamber with air.

The rocket is launched by quickly sliding the larger tube into the smaller telescoping tube. Compression pushes the rocket off the smaller tube. Air rushing over and into the whistle on the rocket body makes a faint whistling “cry” as the rocket flys away from you. You can hear the whistle as the rocket decelerates.

The whistle is audible, but not as loud as I had hoped.

To mount a whistle like this on a model rocket would require cutting a hole through the body tube to mount the internal chamber.
Making a model rocket whistle during boost would involve designing a whistle that would be loud enough to be heard after the thrusting phase.
The whistle activation would have to match the speed of the rocket. Enough air would have to be directed into a whistle or reed to be heard from the ground.