Z-5 Analog Abstract Generator

[DZ]

You can tell how long I've been out of this game. What is "ILDA in"?

Hey Ash, just about any projector you buy these days or for the past several years has a DB-25Male connector. Some also have a female db-25 to daisy chain another projector to do the same thing. In the ILDA specification X and Y are differential signals instead of single ended, which greatly reduces noise. So on the console, the ILDA in converts the differential signal to single ended for the rest of the circuit, then right before leaving the console it gets converted back to differential. The color lines can be differential as well, but the only DAC I know of that outputs differential for color are the older Pangolin QM2K's.

[AshMcFadden]

The P-4 manual arrived from Ireland in yesterday's post, along with a 6-foot length of 58mm G-12 spiral-wound fiberglass tubing, assorted carbon fiber parts and a sweet little ogive nose cone. Two projects at once.

I've almost got the P-4 manual turned into a Z-5 manual. Just a few questions left between DZ and me to make sure I know what has changed and what hasn't, then I'll publish it here. N.B. There will probably be some corrections.

The G-12 tubing project will take a little longer. The plan is to send it through 20,000 feet at about Mach 2.5 in May, then get it back (GPS tracking) and certify the flight from the inflight data recorder for a new Irish altitude record.

[mophead]

Wow!! I really hate we're going to miss this one. Someone better take some video.

Please......

[buffo]

The G-12 tubing project will take a little longer. The plan is to send it through 20,000 feet at about Mach 2.5 in May, then get it back (GPS tracking) and certify the flight from the inflight data recorder for a new Irish altitude record.

Holy crap! An old-school laserist who is also into high-performance rocketry? SCORE!

If you come to FLEM, you absolutely *must* bring some pictures of your rocket designs!

Wow!! I really hate we're going to miss this one.

It's not too late Doug... Just jump in the car with Mistrys and call "ROAD TRIP!"

Someone better take some video.
Please......

I'll try to remember to set up my gopro...

Adam

[AshMcFadden]

OK, off-topic, but, yes, I am a rocket scientist.



And...

[Galvonaut]

OK, off-topic, but, yes, I am a rocket scientist.





And...

WoW! I bet your car goes really fast with that on the roof

I used to make rockets as a kid - these look soooo much cooler!

Keith

[AshMcFadden]

The one on my car and the one in the bottom picture are almost twins and anyone who's built an Estes Industries model rocket would understand everything about how these two work. There are no avionics onboard because (a) they don't need them and (b) avionics tend to malfunction in the salt water after splashdown in our recovery area (aka N. Atlantic). These are BDRs - Big, Dumb Rockets.

When you're trans-sonic, life's a bitch. Solid fiberglass fins become rubber bands. Zero to Mach in 1,000 feet is no record, but it's what a 3-inch diameter, 6½-foot-long dart named "Buster" does on a fairly regular basis. Burnout is at 4,000 feet, apogee 12,551 feet on the last flight.




Buster was preceded by the same design, but built from a new phenolic composite airframe material the manufacturer claimed was lighter than G-12, but just as strong. Moosepies! When the upper fuselage shredded going trans-sonic, the avionics bay disintegrated with it, but the booster section continued upward to some ungodly-serious altitude, then came roaring straight down at Mach+ (you shoulda heard the bang) leaving a smoking 3-inch hole in a sheep pasture. It took us twenty minutes to dig down to the tail fins, which were two feet underground. The front of the booster section was five feet into the rocky soil.

We've never trusted anything but G-12 and carbon fibre since then.

[ekeefe]

Hello,

Your rockets look awesome!

What do you use for fuel/motors?

I have built Estes rockets since I was a kid. The tallest was the "Mean Machine" at about 6 feet:

http://www.amazon.com/Estes-1295-Mac.../dp/B0006NAS12

My favorite type were the multi-stage rockets. I mostly built kits, but I have made a few simple rockets of my own. Mostly under two feet tall.

I agree with Buffo, "SCORE!". Rockets and analog laser consoles, what a combination!

ED

OK, off-topic, but, yes, I am a rocket scientist.



And...

[AshMcFadden]

Ed,

I use "APCP": Ammonium Perchlorate Cast Propellant. It's a mixture of Ammonium Perchlorate and powdered Aluminium mixed in with a propellant that resembles liquid rubber, then poured into a mold to harden. It's the same fuel used in the Space Shuttle's Solid Rocket Boosters (SRBs) and most all other commercial and military solid fuel rockets. In America, we can blend our own propellants. In Ireland, we're restricted to commercially-produced motors. No problem. A friend of mine is using commercially-produced motors by the same manufacturer I buy from to put small payloads into space for NASA. As long as it's a commercial motor, size doesn't matter. Right now, we're resticted only by the Irish Aviation Authority's 100,000-foot ceiling waiver and money. I'm sure I could get a waiver for an Irish space launch and we could build the rocket to do it, if we had the money. No bucks, no Buck Rogers.

[ekeefe]

Hello,

When you build your motors, how do you port them? Do you use a tube or star?

Here is a picture of what I mean:



The star provides more surface area so more propellant burns quicker increasing thrust. I have seen this done with a tapered star that reduces the size of the star, and as a result the thrust. This provides a larger impulse for lift-off along with longer burn time after that.

ED