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  #11  
Old 02-21-2023, 02:11 PM
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BEC BEC is offline
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Quote:
Originally Posted by MrTwisty
I'm actually glad the Super Orbital Transporter is off that much (just got one and have limited field space so hopefully after trimming the glider it will stay on the grass).

What I want is accountability.
Legitimate numbers.
Not for me.
For the kids.
If my first rocket lawndarted I probably wouldn't be here today.

But novices look at those face cards and plan accordingly.

I concur with that last statement.

I don't think they (meaning John Boren and whoever may have been helping him at the time) simply repackaged the upper stage of the Sasha (and changed the motor mount to 18mm) without test flying it on all the motors on the face card. But they are flying well above sea level there in Penrose or Pueblo, so there is some difference in performance. That said, that altitude estimate seems about as far off as it is for the Super Orbital Transport.

What is the estimated weight for the ESAM from the face card (if given)? I know I seldom hit the estimated weights, but my builds are usually not much over the estimates. For example, Estes calls out on their web site 5.4 ounces for the SOT. Mine came in at 5.7.
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  #12  
Old 02-21-2023, 03:57 PM
MrTwisty MrTwisty is offline
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There's no weight listed on either face card and being a HL exclusive the ESAM isn't posted on Estes website.
But the Red Nova is listed on the website and the official estimated weight is 85g.
So considering both rockets were built by me with the same gluing and painting techniques I would expect my ESAM weight to be correct and not grossly over.
I'm at about 250 foot elevation and I know drag racers love Vegas motor speedway because that 2,000 foot elevation is at the sweet spot where the air is thin enough to reduce drag but still thick enough to produce power.
But I wouldn't think that would be enough of a factor for a safe launch- but then I'm not a rocket scientist.

There's obviously something amiss considering the ESAM is larger and heavier than the Red Nova no matter how its assembled.
The ESAM is one of my favorite rockets nowadays and gets launched often, I'm hoping someone else will chime in with their own ESAM statistics.
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  #13  
Old 02-21-2023, 06:38 PM
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ghrocketman ghrocketman is offline
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I have always found Estes max altitude estimates WILDLY optimistic.
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  #14  
Old 02-21-2023, 10:14 PM
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mwtoelle mwtoelle is offline
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Quote:
Originally Posted by Bill
Estes used to recommend an A5-2 or A8-3 for the Big Bertha, not not today. Did she get big and heavy and fat with age or did motors lose power?

http://www.ninfinger.org/rockets/no...a/69est016.html


Bill

These days, an Estes A8 motors is really about an A3. That probably happened when the A8 was switched to the 1/2A6-A8-B4 sized nozzle. There are a couple of other Estes motors that really don’t match their average thrust designation such as the A10. I would consult the motor data from the NAR S&T site for more correct info.
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  #15  
Old 02-22-2023, 01:09 AM
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I am guessing that an A10-3T would be better than an A8-3 for a low Big Bertha flight since the casing is lighter.


Bill
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  #16  
Old 02-22-2023, 07:24 AM
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I am wondering about an expert build with minimal glue and no paint. If the fins aren't sanded perfectly it can cause more drag.
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  #17  
Old 02-22-2023, 02:44 PM
MrTwisty MrTwisty is offline
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Alright I dug through my parts rockets box and pulled out a decommissioned Crossfire.
Little bit of glue and we're in business.
Looks like same ID as a quarter. $3.25 in change brought it upto 106g.
Any bets on the results of tonight's launch with a B4-4?
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  #18  
Old 02-22-2023, 05:54 PM
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The A10 is a lot closer to a "10" than the A8 is to a "8".
Still calling the A8-x an A8-x is a BAD JOKE.
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  #19  
Old 02-23-2023, 06:04 PM
MrTwisty MrTwisty is offline
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Alright so this was a brute force caveman trial but I think it proves a point.
Reclaimed Crossfire ISX (structurally sound).
$3.25 in quarters jammed into it bringing it upto 106g.
B4-4.
Motor hook bent out of the way for a rear engine eject (since the quarters blocked off the motor tube).

Choosing a black and silver rocket for a dusk launch probably wasn't the best choice but it's still visible.

https://youtu.be/gbDiZlSv8yM

Hard to tell in the video but it landed downhill from the launch pad so that was a few additional feet of drop (ESAM landed a little uphill).
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  #20  
Old 02-23-2023, 06:43 PM
Scott_650 Scott_650 is offline
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Quote:
Originally Posted by MrTwisty
There's no weight listed on either face card and being a HL exclusive the ESAM isn't posted on Estes website.


The estimated weight for the ESAM is listed in the instructions - page 6, below the launch/flight/recovery diagram - 3.1 oz/87.8 g.

Edit.

Mine, with recovery gear, weighs 3.5 oz - I don’t build particularly light and mine has a kevlar leader, triple length woven elastic shock cord.
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