if anyone should happen to have a big bertha with a balsa NC...would you be so kind as to measure the length? thanks
reason I ask is I ordered a bnc60L from semroc thinking that the plastic noses were essentially the same as the balsa as far as shape and measuremt go....looks like I need to do some digging.
rex

after doing some research, I've found that, a) the classic goony bird nc is exactly the same shape and length as the current bertha nc, b) the fins on the current big bertha are approx 0.5" longer than the original fins, c) the original nc was indeed a 0.5" longer than the current version, d) the nc60L had shrunk by 1974, oops.
rex
edit
the current version nc bertha/goonybird is listed as semroc BNC60LP

The current shape is duplicated with the SEMROC BNC-60MS, while their BNC-60L is a correct-shape copy of the earlier Estes original. If you're trying to duplicate the original BB, use the SEMROC BNC-60L...

[Addendum] The SEMROC BNC-60LP is a new release, but the 60MS is an elliptical and seems to more closely match the ones I received in both the BB and Baby Bertha kit bags...

There are, IIRC, at least three, and possibly four, sets of fins for the Big Bertha (and her cluster-engined sibling, the Ranger). The fin shape changed slightly each time. The earliest shape/size can be found on the DOM plan sheet #13, which pre-dates the kit release. Here is the JimZ link to that plan.

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well the rocket only has to look sort of like a big bertha...people are not going to get a good look at it once the G67(38/120) comes up to pressure....
rex

That's pretty much what I was thinking.

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...and the BNC-60LV is a copy of Vern's original Big Bertha, which probably pre-dates all the plans for the Big Bertha. It was more than likely pulled from the BNC-60L bin used to kit the Rangers at the time. We use the BNC-60LV in our Retro-Repro Ranger.

Vern's Big Bertha has been flown several hundred times from what I understand. The nose cone still looks like it was not been replaced or sanded since it was first painted. The fins have rounded tips, probably from some rough landings and subsequent sanding. The parachute looks to be the original 12" x 12" square black plastic sheet, but the shock cord mount has been replaced several times and currently has the tri-fold used first on the Alpha years later.

There is no engine hook, but Vern left the engine with a 3/8" or so overhang so he could wrap a few turns of masking tape around the bottom of the engine tube and exposed engine tube. Simple, but elegant.

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Carl McLawhorn
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semroc.com

hmmm guess the shape etc. gradually changed due to wear on the cutters then was set in plastic. thanks for the info.
rex