3" dia Falcon GAR-1D

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El Phantasmo

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I'm designing a nearly 1/2 scale model (3.1" dia).

Does anyone know where to get some scale data on the part that joins the mid and rear fins together? It's circled in green on the attached picture, and it's the only thing I can't find. No biggie, I made a guestimation that I'm happy with if nothing comes up.

Falcon-emphasis.JPG
 
Look at Jim Ball's Scale Data at Rocketry Online. There is a series of close up photos the the Falcon missile. The have a ruler to gauge size from and show lots of details of fins, including the hinge area you highlighted.

This may not be exactly the model your trying to build but it looks close.
 
If you can wait a few weeks until my next rocket club meeting I can get you exact measurements of any part of the missile. There is one on accessible display at the Calgary Aerospace Museum where we have our meetings. Ted
 
Thanks guys.

Dedleytedley, I've got plenty of time. The pictures on Rocketry Online stuff adds lots. I'm drawing up either the GAR-1D or the AIM-4D, whichever I can get the most data/best data on. Could you attempt to get a measurement of the radius of the nose or the distance over the top of the nose and circumference at the start of the measure over the top? See attached pictures for clarification.

Thanks again.

Falcon-emphasis.JPG
 
If you can wait a few weeks until my next rocket club meeting I can get you exact measurements of any part of the missile. There is one on accessible display at the Calgary Aerospace Museum where we have our meetings. Ted

:eek:
Oh my....
If you could post this information on TRF we would be VERY grateful.
 
Our next meeting is on April 10. I'll take a bunch of pics and measurements then. Funny thing about the missile... I mentioned it at the last meeting and our president said that the museum believes it belongs to the rocket club!?! Ted
 
Our next meeting is on April 10. I'll take a bunch of pics and measurements then. Funny thing about the missile... I mentioned it at the last meeting and our president said that the museum believes it belongs to the rocket club!?! Ted

WOW! Get it in writing. That's a lot of cool points for a club. Then you can have a plaque at the museum that says something like:

AIM-4D Falcon
Hughes Developmend
On Loan from YOUR CLUB NAME HERE.
 
Additional measurement (ASE standard or metric):

Circumference at largest body diameter. (I found conflicting data again...)
 
After the last post I recalled seeing this at another site. It took me a while to locate it. It is a scale drawing by Peter Alway, from an old site of his, of the GAR-1D.


https://www.rocketryonline.com/jimball/alway/images/falcon.gif[/URL]
 
After the last post I recalled seeing this at another site. It took me a while to locate it. It is a scale drawing by Peter Alway, from an old site of his, of the GAR-1D.


https://www.rocketryonline.com/jimball/alway/images/falcon.gif

That's where I got most of my initial measurements. There's just some things that are missing, such as the radius of the nosecone, the fin hinges, a few canard dimensions and the radius of the curve at the front of the large fins.
 
Here are the promised pics and requested dimensions pus some more that might be useful.Fin connector:total length 260mm,9mm wide 12mm thick at rear has a rectangular profile increasing to 24mm thick @ 135 mm from rear, profile then changes to oval and tapers to the angled ridge on the upper fin. Upper fin ridge goes from 85 mm to 310 mm at an angle measured from the rear of the front fin. The radius of the leading edge of the front fin is 30mm from the airframe it continues as a straight line for about 50mm and curves again with the same radius to the straight line of the edge. Fin Strake is 10mm thick and 38mm wide, ending in an ogive 110 mm long. Max. circumference is 510mm. The radome measures 325mm circ. and 143mm over the top. The total length of the nosecone and radome is 200mm and it is 165mm to the radome from the N.C. base. The lower fin starts as rectangular profile 5mm thick for 68mm from the bottom then tapers to 1mm for 51mm, it has a thickening to a diamond profile as it meets the airframe. I hope this helps. I took quite a few pics so I will add additional posts.

rockets and stuff 2 053.jpg

rockets and stuff 2 054.jpg

rockets and stuff 2 055.jpg

rockets and stuff 2 056.jpg

rockets and stuff 2 057.jpg
 
Neat project. You wouldn't happen to have a Rocksim file to share would you?
 
Thanks to all for the pics, data, and Rocksim file. Think I'll build one too
 
Here's my CAD drawing I converted to PDF. Feel free to check the measurements; I rounded all mine to the nearest 1/16, except for one measurement on the canards. The scale is 1:2.066. Also attached is the drawing I took most of my data from.

View attachment Falcon_2.pdf

falcon.gif
 
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It's interesting how different the scale drawing is from the actual missile in the photos in terms of outline. Ted

rockets and stuff 2 074.jpg
 
It's interesting how different the scale drawing is from the actual missile in the photos in terms of outline. Ted

This is true. The scale drawing (GAR-1 by Peter Alway) I got most of my major measurements from, I believe, either simplified or ignored the detail of the leading edge of the large fins and the nosecone. Although, it does show a slight taper from the body to the nosecone, which I cannot make out this detail on real photographs of AIM-4x models.

The nose cone on the real Falcon has more of an egg shape that is difficult to reproduce from the pictures, but I'm working on it. I recently found an easy method for making egg shapes with whatever dimensions are desired.

The front/top of the large fins seem to be made of 2 curves before the straight portion of the leading edge, making a for a less abrupt rise away from the body as my scale drawing does. Duplicating compound curves is a bit tricky for me from pictures. I'm also working on that.

Also, the Peter Alway scale drawing is of a GAR-1 and the "real" photos are probably of an AIM-4D. I think the nose cone went from round on the GAR-1 to egg shaped on the AIM-4x models. Right now I'm not sure which model will be my final design. Maybe both...

Right now it's a work in progress and I appreciate all help and comments. Does anyone know any septuagenarian that may have worked with these missiles?
 
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One of the reasons that you are seeing slightly different shapes between missiles (the "same" missile?) is that missile manufacturers often produce these things in batches (sometimes called lots, rounds, blocks, tranches, and other terms). Within that batch (of the same model) the detailed configuration is probably pretty constant. From batch to batch there can be small changes if a new subcontractor is chosen to make the "same" warhead, or the "same" motor, or the "same" steering package. It is pretty easy for there to be small differences that 99.999% of people would never notice.

It happens all the time.

That's kind of why you need to select one example, get photos and measurements and markings for that one single example, document that one, and identify your scale model as that one missile, at least for contest purposes when you submit a "scale" model.
 
One of the reasons that you are seeing slightly different shapes between missiles (the "same" missile?) is that missile manufacturers often produce these things in batches (sometimes called lots, rounds, blocks, tranches, and other terms). Within that batch (of the same model) the detailed configuration is probably pretty constant. From batch to batch there can be small changes if a new subcontractor is chosen to make the "same" warhead, or the "same" motor, or the "same" steering package. It is pretty easy for there to be small differences that 99.999% of people would never notice.

It happens all the time.

That's kind of why you need to select one example, get photos and measurements and markings for that one single example, document that one, and identify your scale model as that one missile, at least for contest purposes when you submit a "scale" model.

That makes sense as the fins appear to be cast aluminum. I could notice some sand-casting marks on the forward fins. I'd guess each maker would use their own molds for casting.making refinements in the design. Ted
 
One of the reasons that you are seeing slightly different shapes between missiles (the "same" missile?) is that missile manufacturers often produce these things in batches (sometimes called lots, rounds, blocks, tranches, and other terms). Within that batch (of the same model) the detailed configuration is probably pretty constant. From batch to batch there can be small changes if a new subcontractor is chosen to make the "same" warhead, or the "same" motor, or the "same" steering package. It is pretty easy for there to be small differences that 99.999% of people would never notice.

It happens all the time.

That's kind of why you need to select one example, get photos and measurements and markings for that one single example, document that one, and identify your scale model as that one missile, at least for contest purposes when you submit a "scale" model.

I figured something like this was the case; however, I don't have access to a Falcon locally that I know of (Houston, TX). And there is not a complete enough set of measurements or photos from a single example of a Falcon.

I don't plan on entering it in any scale contests; besides if I can't find the "correct" data and have to extract it from several different sources, then how will the judges be able to score it? I don't need it to be mistaken for the real thing (i.e. screw heads and panel seems), just a damn good model rocket of a Falcon missile.
 
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