Breathing apparatus necessary above 25,000' - apply now to the TRA BoD if you're planning on going over the established waiver limits. Unless you're like the late Sir Edmund and can rough/tough it out. We've got General clearance to 20K. Beyond that, ask permission of the BoD and hope all of our paperwork is in order.

A vacuum chamber? Please, this whole project sucks! 😉 Notice the altitudes Joe mentioned... there's no wonder why this guy gets elected Prez year after year.

Breathing apparatus necessary above 25,000' - apply now to the TRA BoD if you're planning on going over the established waiver limits. Unless you're like the late Sir Edmund and can rough/tough it out. We've got General clearance to 20K. Beyond that, ask permission of the BoD and hope all of our paperwork is in order.

I said 15 or 20,000. Besides the waiver I have other things to worry about, note the Far Regs.

91.211 Supplemental Oxygen

(a) General. No person may operate a civil aircraft of
U.S. registry —

(1) At cabin pressure altitudes above 12,500 feet (MSL) up to
and including 14,000 feet (MSL) unless the required minimum
flight crew is provided with and uses supplemental oxygen for
that part of the flight at those altitudes that is of more
than 30 minutes duration;

(2) At cabin pressure altitudes above 14,000 feet (MSL) unless
the required minimum flight crew is provided with and uses
supplemental oxygen during the entire flight time at those
altitudes; and

(3) At cabin pressure altitudes above 15,000 feet (MSL) unless
each occupant of the aircraft is provided with supplemental
oxygen.

And above 15000 I have to supply all the passangers with oxygen. I may have to get a stronger vacume pump, to pump out all that oxygen I have to pump in!
😯
Scott e

I tested one of my new Missle works Altimeters today. Not Bad. Made three runs in the vacume chamber. Started at 5000 feet (since thats our altitude here) and took it strait to 10000 each tilme. I come to find out, alot of my home made matches are duds (not the fault of the altimeter). Again just seem to snap the tip off. Any way, the last time both matches lit properly.
I let go of the pump button when the airplane altimeter hit 10,000. A second later the droug match lit. I bled pressure off, well I mean, I let pressure back in to the chamber slowly, and the main match lit close to 6000 right where I set it at. Way Cool! 8) Funny the Missle Works Altimeter reported 5034 feet all 3 times (maybe it measures in multiples or somthing). Hmmmmm. Well any way, not bad I guess. Pretty accurate. 34 feet give or take. The AirPlane altimeter isnt certified, so it might be off 50 foot or so. Its pretty neat to see the match light right where it supose to, up close and personal! 🙂 I still need to clean it up and finish some of the details but it does exactly what I wanted (checking and testing a rocket altimeter against another readable Altimeter in a fairly controled environment). See Pictures at the linc below.

http://good-times.webshots.com/photo/2590174110102900583UxrADB

Breathing apparatus necessary above 25,000' - apply now to the TRA BoD if you're planning on going over the established waiver limits. Unless you're like the late Sir Edmund and can rough/tough it out. We've got General clearance to 20K. Beyond that, ask permission of the BoD and hope all of our paperwork is in order.

You know Joe
To try and take this thing to 25,000 MSL, I might be left with a pile of Plexyglass splinters! Use your saefty glasses!

Scott e.

Yes do use safety glasses. In fact I would have recommended to use even thicker material. I use 1/2 and 3/4 inch thick Lexan/acrylic when I vacuum process my propellants and even then I end up with more or close to 3/8 inch deflection in the surface. Im running at 28" and with 5cfm down to 40 microns.. So it can be scary. Just be careful.

BTW each of the missile works stuff is all calibrated by vacuum chamber. In fact a very expensive highly accurate 100,000 ft + capable one.

Yes do use safety glasses. In fact I would have recommended to use even thicker material. I use 1/2 and 3/4 inch thick Lexan/acrylic when I vacuum process my propellants and even then I end up with more or close to 3/8 inch deflection in the surface. Im running at 28" and with 5cfm down to 40 microns.. So it can be scary. Just be careful.

BTW each of the missile works stuff is all calibrated by vacuum chamber. In fact a very expensive highly accurate 100,000 ft + capable one.

DUDE, Way beond what im doing! Although I thought 1/2" would have been better! Especially since we cant get that transparent aluminum from Star trek 4 yet. I dont even know what a micron is!

Scotte 🙂

BTW each of the missile works stuff is all calibrated by vacuum chamber. In fact a very expensive highly accurate 100,000 ft + capable one.

Nice to know! First time I heard of that one. Im just worried about getting back $500.00 rockets and $100.00 electronics gear!

Scotte

I dont even know what a micron is!

Scott, a micron is a very small moron, or a millionth of a meter.

Yes do use safety glasses. In fact I would have recommended to use even thicker material. I use 1/2 and 3/4 inch thick Lexan/acrylic when I vacuum process my propellants and even then I end up with more or close to 3/8 inch deflection in the surface. Im running at 28" and with 5cfm down to 40 microns.. So it can be scary. Just be careful.

BTW each of the missile works stuff is all calibrated by vacuum chamber. In fact a very expensive highly accurate 100,000 ft + capable one.

DUDE, Way beond what im doing! Although I thought 1/2" would have been better! Especially since we cant get that transparent aluminum from Star trek 4 yet. I dont even know what a micron is!

Scotte 🙂

For what I use it for its to pull as much as possible of the air that has been induced into the propellant when I mix it. Its done this way so I can achieve a better propellant with higher density and more uniform consistency throughout the propellant. A micron is as Bruce states 1,000,000th of a meter. Its a value for me thats important as it will tell me what the smallest particle i can pull out via the vacuum pumps capability. The smaller that number the better. My next pump will be able to pull down to 20 micron.

But what you have going for your project sounds pretty cool. Great way to see if your matches are working.

BTW Bruce I just about had to get up off the floor with that very small Moron bit. Thanks for the laugh.

Are you sure thats what a Micron is? That would mean every one in Battlestar Galactica was very very tiny. Even Lorne Greene! They would never get to earth, at the rate they would have been traveling! So when the cylons were 500,000 Microns away, and closing, they were only half a meter?

Conway
I would like to see one of your vacume chambers some time. I bet your pumps are alot more expensive than mine. 29 inches probly is 100,000 feet or so.

Scott e

Indeed, the micron is 1 millionth of a meter and was originally called the micrometer. (See millimeter, centimeter, decimeter, etc. etc.)

However, I think it popular culture making it a millionth of a moron at least is a helluva lot funnier. I almost choked on my coffee over that Bruce. Thanks for the chuckle.

Warren

Yeah, where did you get your pump?

Santa brought me one for Christmas from Aircraft Spruce that I thought was going to suck out at least 80-90% of atmospheric pressure, but sadly it doesn't suck that much...er... well, you get the idea. I did a test and it was only able to simulate an altitude of 12k ASL (6k AGL), which is better than 3k from a shop vac, but not worth $300, since it's also rather slow. I'm a little skeptical about its ability to remove bubbles from vacuum layups at that rate, even though that's what it's supposed to be for. I'd really like something good to 30k or more.

My vacuum pump pulls to 25" Hg... don't know what that corresponds to altitude-wise or in millibars or whatever, but it sure can pull v-bagging down tight on a lay-up.

Warren