Aerobee 100--an interesting new find.

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PeterAlway

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It seems that the Aerobee 100 (Aerobee Jr) photo I used for my NRL-51 drawing was deceptive. They photographed the rocket with the standard Aerobee nose, but then they pulled it off and replaced it with a weird nose consisting of a tapered adapter and an Arcon payload. I found evidence of this years ago, and put a little note in a later edition of my drawing that it was the rocket as photographed, rather than as flown. Today, Dan Meyer was kind enough to send me some material that included this photograph. I intend to do an accurate drawing at a later date. But I thought I'd let people see how weird this Aerobee looks.

Aerobee 100 NRL 51.jpg
 

tsmith1315

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I've been trying for a year to hold off doing a small Aerobee build. Sigh... I guess now I don't have a choice, except for the scale.

Thanks for posting, Peter!
 

Ez2cDave

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Peter,

That's a very interesting photo. It appears that the Fairings extend into, and follow the taper of, the Transition Section.

Dave F.

1634616362426.png
 

JohnCoker

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That's a great photo. Being perpendicular to axis of the rocket really helps with detail placement.
 

Ez2cDave

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It seems that the Aerobee 100 (Aerobee Jr) photo I used for my NRL-51 drawing was deceptive. They photographed the rocket with the standard Aerobee nose, but then they pulled it off and replaced it with a weird nose consisting of a tapered adapter and an Arcon payload. I found evidence of this years ago, and put a little note in a later edition of my drawing that it was the rocket as photographed, rather than as flown. Today, Dan Meyer was kind enough to send me some material that included this photograph. I intend to do an accurate drawing at a later date. But I thought I'd let people see how weird this Aerobee looks.
Peter,

What is the source of the documentation regarding the use of an ARCON on NRL-51 ?

The reason I ask is that the AEROBEE 100 has a diameter of 15.00" and the ARCON has a diameter of 6.09" ( 40.6% of the AEROBEE 100 diameter ).

Also the AEROBEE 100 motor has an overall length of 143.1" and the ARCON motor has an overall length of 102.6" / 102.56", per ROTW . . . ( 71.7% of the overall length of the AEROBEE 100 motor ). In scaling the "ARCON", I allowed for its overall length to extend to the bottom of the Transition Section. It was measured minus Nose Cone.

In scaling the photo of NRL-51, it appears that it might not be an ARCON. The diameter appears to be correct for an ARCON, but the overall length is MUCH shorter ( 38% vs. 71.7% ) . . .

Thoughts ?

Dave F.

Aerobee100.jpg



arcon.jpg
 

PeterAlway

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Here's a dimensioned drawing, but it has errors. I believe the dimensions are correct, but instead of a cylinder-ogive payload it shows a sort of cone-obive payload that doesn't match the photos. The report says that ogive is an Arcon nosecone. I have a copy of a brochure at home that gives a diameter of 6.09" and a length of either 30.25 or 31.25" (I have the data at home, not at the library, and the lengths are different in different sources). I have another document that gives a half-angle taper for the conical adapter of 7.5 degrees, which gives a length close to what the drawing shows, if you allow for that cylindrical bit at the base. That other document also gives an overall length that's pretty close to this drawing. This sort of thing is why I do my own drawings, and don't just reproduce drawings that I find.

The bottom main drawing shows the Aerobee 100 with the default nosecone. White Sands or Aerojet took pictures of this round with a default nosecone at the launch site, and then they switched to the weird flight nosecone.

Aerobee NRL 51 drawing.jpg
 

UhClem

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That looks like an angle of attack probe on the nose tip.
 

PeterAlway

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So here is the picture that misled me for years. Same rocket, different nose. Evidently Aerojet provided the standard 87.81-inch ogive with the rocket, but the NRL swapped it out for the flight nose (in the picture above) before launch. I guess Aerojet wanted a picture of the default configuration, so they posed the rocket with the original cone for this photo:

Aerobee 100 with standard ogive.png


Here is a factory photo with yet another nose:

Aerobee 100 mockup-model.png


It's not clear if this is a live round or a mockup. The caption calls this a model, but so does the caption of the very much live NRL-51.
 

PeterAlway

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Ugh. Quotey thing not working.

By "Arcon payload," I mean the payload was a payload originally designed to be flown on an Arcon. I don't mean that the payload is a complete Arcon rocket, flown 2-stage. So it's an Arcon nosecone with an Arcon-diameter payload cylinder. The source for this is from the report Mr. Meyer was kind enough to send me.
 

Ez2cDave

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By "Arcon payload," I mean the payload was a payload originally designed to be flown on an Arcon. I don't mean that the payload is a complete Arcon rocket, flown 2-stage. So it's an Arcon nosecone with an Arcon-diameter payload cylinder. The source for this is from the report Mr. Meyer was kind enough to send me.
Peter,

Thanks for clarifying that !

Dave F.
 
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