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Well, the old R-DAS was in the neighborhood of $330, so I'm guessing it will be cheaper than that. How much cheaper will be interesting to see though - I had a couple of the RDAS tinys (v4 I...

Sukhoi T-50.

I agree with most of this, but I would like to correct one thing: typically, motors come with delay charges up through K or so. You can (and I frequently do) fly motor deployment on a 4 inch rocket...

I'll be the dissenting opinion here - my Kraken (7.5 inch, 87 pounds on the pad with an N2801) had the tubefins just surface mounted, and it didn't have the slightest problem with either the flight...

I think cvanc means that the O3400 by itself is 37 pounds. Without looking up the specific numbers, that does sound about right, since imax is substantially denser than C*, and the N5800 is 32-33...

It's a nice long rocket with plenty of fin - I would not expect it to need noseweight, even on a 98-6xl load. Definitely mark the CP on it once you're done, and check the balance point when it's...

Actually, I wasn't too worried on my first flight - the N2801 is a pretty tame motor, and it weighed a LOT on the pad. My question was more related to future flights - I have both an N4100 red and an...

Fascinating - I've wondered for some time about tubefin shreds. Any idea how fast it was going when it came apart?

Not necessarily. Here's a finocyl thrust curve (with a moderate burnrate): http://pro38.com/products/pro150/motor/images/29920O3700-P.pdf
Here's a bates:...

You could probably get a bit more impulse out of it if you did a stepped core, but the thrust curve would be a bit strange.

Not necessarily. In general, the diameter and propellant type will be the biggest factors, and you really won't see a significant effect from motor length until you start to get to fairly long motors...

I've been down to SCORE quite a few times - you guys have a nice site. I've even managed to avoid the rocket-eating canyons so far, despite launching down there for the past several years (I'm sure...

I'm not convinced that's true, given proper composite construction. I'm not sure you could ever achieve the required (aerospace-grade) construction techniques to do it, but at least in theory, the...

I still believe that as well, even though my first composite attempt at the 5800 failed. Hopefully, I can give it another try next year - I have some ideas that may improve my chances in the future,...

Hartsel is awesome - in some ways, it's my favorite of all of the Colorado launch sites. Welcome to TRF, and I look forward to seeing you at a launch sometime :D

Agreed. I wish they still existed - Fruity Chutes are probably my top pick among currently existing vendors (the Iris Ultras are quite nice), but I've yet to find something that could quite match the...

Actually, it shredded on the way up. The nose cone and front section of body tube came off at a bit over mach 2, and the booster was still stable by itself (so that's just the booster right there).

Yep. If you fly high power for long enough, eventually you discover what the inside of a Duracell looks like. Here were some remnants from my largest failure to date:
...

Actually, it's easier than that - I just assumed that the exhaust velocity would be unchanged (a pretty darn good assumption, since the flow is fully choked in either case), meaning that the momentum...

Why does it disgust you? It's 2% off, which is close enough that some of them probably are M motors in reality, depending on manufacturing tolerances and conditions on the day of flight. There's...

Honestly, I wouldn't be hugely concerned with heating on a flight like that. You're above 20k before you pass mach 2, and you never hit mach 3.

A 4 inch rocket can absolutely hit a mile on a J. It's not all that hard either, but it would need to be a fairly sleek rocket (nice finish, good long boattail) to do it at a weight of 11 pounds (on...

That's one of my favorite books - I don't know how many times I've read it. Definitely a wonderful read, and it reveals a lot about the design and manufacture of Lockheed's aircraft around the time...

Saw it opening day (not at midnight though), and loved it. I can't wait for the next part to come out.

I was just about to post a nice long answer (which could be summarized in two words: NO), but then I saw that stealth6 had already stated it quite nicely for me. Basically, I agree strongly with...

I'm pretty sure the engines are made in the states - in colorado, to be precise.

That's not really the comparison that makes the most sense here though. It would be better to contrast a ramjet (where the inlet provides the compression prior to combustion) to a turbojet (where all...

As best I can tell, what people are trying to say with that sort of figure is that the core of the engine was basically superfluous at full speed - the vast majority of the air got compressed in the...

Why? The back of the motor shouldn't get anywhere near hot enough to soften the JB weld, and on the bigger motors, you can use the flanged kind anyways.

Not without damaging the tube - JB weld's heat resistance is too high. That having been said, as long as a casing still fits, it's purely an aesthetic issue, so I wouldn't worry about it.