Ammunition related?

I just purchased this highly engineered, “Thing,” thinking it may be ammunition related. I was thinking it may be a whale harpoon part (makes me sick) or projectile tip but could not find anything like it while searching whale harpoons on the net. It also could be a missile tip, plane part or something else. What ever it is, it could not have been cheap to make or buy. There are almost no markings on it expect for 688-82-3 which is hand engraved.

Anyone have a clue on this?


The only threads are internal located where the 5th inner ring starts.

Is it steel or aluminum? Do you know if the little screw holes are metric or standard? If they are standard then that probably narrows it down to British or U.S.

My whimsical guess: A NASA plumb-bob

Based on weight, I would think steel for sure. It is very heavy. Not sure about the screw holes being metric or standard in size.

Thanks so much for your ideas and help. Maybe it is a plumb-bob. If it is, I hope it is from NASA :-) That would make it the coolest plumb-bob ever.


Jason, my vote is that it’s a wind tunnel test model, maybe actual size or maybe scaled down (or up). The polished finish is consistent with that, as are the screws that hold the two rounded shapes to the main body. Different shapes could be installed to see how they affected the aerodynamics. The one threaded hole about halfway down would have been how the body was secured to a post to hold it in place in the center of the tunnel. The scribed number is also consistent with a one-off device. It looks sort of like a hypervelocity missile point, but the rounded shapes are strange. A letter to NASA would be cheap and you might just get an answer. Or a knock on your door.


The only comment I was going to make was that it appears far too well made to be anything ammo related. Based on engineering hourly costs there are some dollars in that.

Great theories!

Mel, the one small hole in the side looks threaded in the photo, but is not. Still, it may possibly still be a source for attachment for wind tunnel studies? There are internal threads located fairly deep inside. Looking at the last photo above, the threads start at the 5th ring from the opening and travel about 1.5 inches towards the tip, so this may have been attached to something much larger? I would have no clue how to contact NASA about it. :-) Totally driving me crazy


Jason, it actually makes more sense that if your “thing” is a wind tunnel model, it would be better to mount it from behind with a mounting device screwed into the base. That way, airflow around it wouldn’t be disturbed by a center-mounted post.

Contacting NASA is easy. Just Google “NASA Public Relations” and you’ll get a long list of NASA public relations contacts in different specialties. They might welcome your inquiry since the U.S. manned space program has been shut down with no replacement for the shuttle.

It also looks sort of like a military flagpole end cap for the short wood poles used in marching formations. These often have lots of unit and campaign streamers attached. Who knows?


Just contacted two NASA employees via e-mail. THANKS BIG TIME MEL!


I agree with Mel. This sure looks like a windtunnel test specimen to me, but it could also be a radar cross section model, or even a flow model to assess Infrared signiture.

The screw hole is interesting. If this model was intended for subsonic/transonic flow it would have to be mounted from the rear as Mel says. If it was intended for supersonic, particularly above about Mach 2, then the model could have a post mount if the area of interest is well ahead of a post because supersonic flow does not allow pressure waves to propogate upstream and the shock wave from a post would only effect downstream flow in all supersonic regions on the model. Having said that I think the single screw hole is not sufficient to hold the model in place and correctly alighed in a supersonic flow.

Radar signiture models are usually post mounted in my experience. Since there is no flow involved there would be no structural issues in such a mount.

The shape of the model looks to me as if it were intended to be designed for high supersonic flow. It could be an intake spike to be mounted ahead of a scramjet engine inlet, a nosecone shape. The two sidebodies imply a control function of some type.

Interesting item…



I have not done any windtunnel testing but I have done work with liquid flow in flumes which are the liquid eqivilent. I did four years in Hydraulic research before going to work for Kodak
In that sort of testing only the shape is important. Things to be tested are made out of wood or more probably plastic now.
I can’t imagine anybody going to that much trouble to make anything that good just for a test model.

But there are clues, it appears to be stainless, that implies to me sea water.

If you replaced the brass looking bits with an impellor I would say it looks like the nose cone off a flowmeter. Such things can either be static or lowered into the sea to measure the current at different depths from survey vessels. Navy guys will have seen similar on ships to measure their speed. In that case one of the inner rings would accomodate a bearing (perhaps) or a seal. The hole in the side in this hypothesis would be for a pin to lock onto in the shaft (again perhaps)

Not a fully formed theory but it does tick some of the boxes.

Vince, With supersonic flow the stagnation temperture (resulting from slowing the air down from supersonic velocity to static relative to the test shape) would destroy a plastic or wood model. Most supersonic models are made from stainless steel in my experience.

Ramjet engines are limited to use at only mach 3 or a bit more because slowing the air down to subsonic speeds in the combustor raises the temperature far above the combustion temperature of any of the hydrocarbon fuels. In fact, the fuel actually cools the air by absorbing energy required to ionize the fuel, and any burning would occur well after the mixture leaves the engine exaust and cools down to the point where oxidation can take place.

Down at Eglin AFB there use to be a ballistic range where the model was fired down an instrumented range filled with still air. In their display case was a 40mm Plastic discarding sabot and inside was a small stainless model of an F-16. The range used a 40mm cannon to launch the test shapes down the range and the range was used for some of the very early testing of the F-16 shape in supersonic flight.

Having said this, you could still be right that it is part of an impeller. On the other hand, the threaded hole could have as easily been a set screw to hold the test shape on a rod which slides in the rear of the item for testing in a high speed tunnel.



WOW, you guys are brilliant.

One thing to note is that while that single hole looks to be threaded, it is not. The only threads are internal starting at about 4 inches inside and traveling about 1 inch towards the tip. It definitely looks like this thing is only the front portion of something larger.


I think there are about 500 more applications for such an item.
Those 2 “cheeks” which look like aluminum make me think it is not related to wind channel testing.

Kinda reminds me of the long tip or spike that was on the nose of test aircraft like the F104, etc. Cheers, Bruce.

This will definitely be something that will drive me nuts until solved :-)


NASA never wrote me back, Go figure :-)


Is the side hole near the threads ?

No, the hole on the side is located about .5 inches from the internal threaded section towards the open end.

I may or may not have a clue as to what your unknown item is. For a number of years now researchers at the USDA (US Dept. of Agriculture) and elsewhere have been working on acoustic detection of insects in bulk stored grains and other food commodities. Over this period of time a myriad of acoustic detector containing grain probes and insect pitfall tube traps (used in stored grain to trap pest insects) have been tested. As a research technician at a USDA research facility in Manhattan, KS I was involved in testing some of these acoustic probes and traps, in the early 1990’s, in stored wheat. These devices were designed and built at a USDA research lab in Gainesville, FL. In additions we were shown, but did not test, grain probes similar in shape to your unknown device. These probes were built of plastic, brass and stainless steel. Some of these devices looked similar to brass or stainless steel grain triers commonly used in taking grain samples. In addition I know (but I’m not familiar with) commercial grain elevators have remote powered/automated grain probe systems used to sample trucks loaded with grain (to obtain the test weight and moisture content of the grain) before unloading the grain at the elevator. From what little I’ve seen these probes have a tip similar in appearance to the device you have.

I’m certain this is not what you wanted to hear but upon seeing your pictures I was immediatly reminded of the the work I was involved in 20 years ago. Wish I had some picture to show but we only ended up with numbers and graphs.


Thank you so much, Brian. At least now I can search for information on “Grain Probes”. Maybe I can find some pictures.