Whistling rocket?

[Handeman]

I've heard several HPR that had a very loud whistle as they shot off the pad although I don't remember ever hearing a good whistle from a MPR or LPR.

I'm wondering if anyone has a "whistle" design that would give a loud and consistant whistle for any size rocket? How dependent is a good whistle on size, speed, acceleration, etc.?

Thanks...

 

[denverdoc]

Interesting that you should ask. I am looking to build a giant whistle rocket and am looking at several ideas. One of the more interesting is using a fluepipe type design like that used on steam locomotives--this requires over an atmosphere of overpressure, but can be very loud--audible for miles, but will require substantially greater than supersonic velocity to achieve.

The whistling you usually hear on some rockets though is of aerodynamic variety like that emitted by bombs. I should think it would be possible to use ordinary whistles in various arrangements. A good place to start might be experimenting just by sticking the whistle out a car window to see what results you get.

IMHO the ultimate flying whistle: https://www.acmewhistles.co.uk/xcart/customer/pages.php?pageid=9

Notice the impeller--my guess is this to to pump up the dynamic pressure into a range where you can get a steam like whistle operating--around 15psi with 100 cubic feet minute of air flow per inch of whistle diameter.

 

[tonypv]

The Fat Cat Ring Leader (oop) whistles great on a G80.

 

[Indiana]

The Estes Screamin' Mimi is oop, but it would probably be pretty easy to find.

 

[Zack Lau]

The QCR Cluster does a great job of whistling on three 13mm motors. It has 1/4" vents on the side pods to let the ejection gases out--only the central motor is used to eject the streamer.

 

[jj94]

The Estes Screamin' Mimi is oop, but it would probably be pretty easy to find.

I heard that they don't whistle well on D12's but they do good on E30's because of the rapid acceleration. Since the E30 produces noise over a short period of time, it gives more time for the whistling effect to be heard.

 

[new2hpr]

Any split fin designs like the Thor and Endeavor whistle nicely. Combine it with a short burn punchy motor and you get more time to hear it.

Ken

 

[DAllen]

This rocket whistles on an F24 although not real loud.

-DAllen

 

[Rockaholic]

I built my 4" Army Hawk (scratch) to whistle...
"all primed and ready to whistle"
Eventually, I'll paint it.
www.tra-la.org

look under videos.
Punchy motors work best.....
the next flight will be on an I1299......
J528 whistled but it was too high up...more whistley on the I405.

Dave

 

[loopy]

I heard that they don't whistle well on D12's but they do good on E30's because of the rapid acceleration. Since the E30 produces noise over a short period of time, it gives more time for the whistling effect to be heard.

Mine whistles quite nicely on D12's. Haven't flown it on AP yet, but that's not such a bad idea.

Anything with a split fin design should whistle at a high enough speed. most rockets will whistle a bit on the way in, if falling purely ballistic...

 

[wolfstar]

Yes, it is a split fin design that makes a best whistler.

I just finished a split fin Mid powered rocket that I was working on just for that Idea, gave it the name "Sky-Wolf". It's also true that the faster you go the louder the whistle, works best on fast burn motors like the G64.

In tests a rounded front fin and not a airfoil works better, as the air passes thru the area inbetween the first and second fin makes the whistle, also helps to have those edges flat and square.

 

[jj94]

Yes, it is a split fin design that makes a best whistler.

I just finished a split fin Mid powered rocket that I was working on just for that Idea, gave it the name "Sky-Wolf". It's also true that the faster you go the louder the whistle, works best on fast burn motors like the G64.

In tests a rounded front fin and not a airfoil works better, as the air passes thru the area inbetween the first and second fin makes the whistle, also helps to have those edges flat and square.

So if I'm understanding you, a rounded front fin and a squared off second fin makes for the best whistler?

 

[wolfstar]

So if I'm understanding you, a rounded front fin and a squared off second fin makes for the best whistler?

thats a BIG 10-4

Take a listen

https://www.wolfstardesigns.com/Sky-wolf.wmv

 

[jj94]

WOW!:surprised: I didn't realize that the whistles could be that loud.

 

[Rockaholic]

WOW!:surprised: I didn't realize that the whistles could be that loud.

That was cool! I'll have to get one!
If you want to hear loud,
check this one out:

https://www.youtube.com/watch?v=WLdX7E7X8Zo

Dave

 

[lmerdan]

Does anyone have guidelines for doing a DIY whistling fin design? What thickness fins and how far between them. Also what angles work? 45 through 90??? What shape should the lead and tail edges be?

Thanks - Lyle

 

[jj94]

Reviving an old thread here. I'm designing a rocket in Rocksim, based off of BSD's Thor, named Thor's Hammer that could become a reality anytime before late summer. I want it to be able to whistle as loud as possible, so are there any tips to get the best whistler possible (besides a rounded front fin and a squared off aft fin)? For example, the distance between the forward and aft fin, the shapes of both fins, etc.