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Originally posted by cjl
Sorry, it's really frozen CO2 (Frozen H2 would be FAR too flammable).
Click to expand...

oh...well what if i have water run out of the main engines, and then the water would run down into a "trough" with the dry-ice in it (see the attachment)...
 
Nice! I thought that you were only doing 1 stage? Hmm... Try that design on it's own (with any stability issued fixed w/ fins & nose weight) to see if you llike it, and then try it with the rest of the shuttle. There was a thread a while back that was about launch pads to make Estes launches look "real" by spreading the smoke, using the flame to boil water to make steam, ect.
 
I wouldnt recommend the F21 motors instead of the E9 for a beginer, hard to light two of those at the same time without experience
 
True, if you use the Crapperheads (from what I've seen and heard, that name is quite appropriate for the Copperheads supplied with the motors)). If Quickburst or other higher quality ignitors are used, they will be much easier.
 
Originally posted by richalex2010
I'm not sure if they will. Why?
Click to expand...

i just wanted to know what was the safest material to use for a body so that nothing would catch on fire...
 
From what I've heard, Totally Tubular sells foil-lined tubing so that may be an option. Balsa Machining Sevices might carry it as well.
 
i have a coasting question. if the rocket is launched at 90 degrees, how can you calculate how far horizontally it will coast? also, if it is a day without wind and i launch my shuttle at a 90 degree angle, how can i get it to fall back during coast?
 
Originally posted by spaceshuttle
i have a coasting question. if the rocket is launched at 90 degrees, how can you calculate how far horizontally it will coast? also, if it is a day without wind and i launch my shuttle at a 90 degree angle, how can i get it to fall back during coast?
Click to expand...

I'm going to have to do some 'interpretive' answering here-

Assuming that "If the rocket is launched at 90 degrees" means you plan to launch straight up..
And assuming that "how far horizontally it will coast" means how far it will glide after ejection/separation..
If your model is a typical scale design it will tend to be relatively heavy, with a correspondingly high sink rate. Combine that with the high sink rate of the original full-size vehicle and you may have a brick falling out of the sky. What does all that mean?
You can probably expect your glider to descend at a 5:1 rate at best. Very likely, it will be much less than that. If you think your boost will carry on up to 1000 feet, you will probably only get a horizontal glide of a few thousand feet, if it travels in a straight line.

Assuming that "how can i get it to fall back during coast?" means: how can I get it to pitch over from vertical boost and transition to horizontal gliding flight, that's an easy one---you use the pitch controls on the glider to 'steer' it over the top near the end of the coasting phase. (I thought you were going to R/C this thing so you could circle it around the field and control the landing?) You want to do this while it is still ascending with some significant airspeed so the aerodynamic controls will be effective. You can't wait until apogee (zero or near-zero airspeed) to try to pitch over because the model will then have to free-fall downward to regain enough airspeed for the controls to work.

You are going to have to be on guard throughout your design and build process to make sure that absolutely NOTHING goes into your glider that doesn't need to be there. If you are not sure about whether to select thick or thin pieces of balsa, pick the thin one. Pick out the smallest servo you can find, and the smallest battery pack to power the controls. Even after you think you have chosen minimum sizes of everything I'll bet your shuttle glider will be pretty heavy. If it flies successfully, **then** you can start adding extra bells and whistles (bigger servos, batteries, more airframe beef, etc) back into your design.
 
well, the whole model is almost 2 feet tall, not remote controlled, and is being powered by 2 estes c6-5 motors. with every thing in it, it weighs a little over a pound (18 ounces to be exact), and according to AltPred, it should peak at 94 feet (i didn't want it the shuttle to go TOO high). i'm working with limited space (the field behind the Rec Center) and on the first flight, i didn't plan to have the orbiter fall off to glide as i was trying to make sure that the coast wouldn't cause the full stack to coast too far.
 
For a just plain glider version of the shuttle, you will have to use a little bit of 'up' elevon deflection to trim for glide. This will have to be experimentally determined by hand-launching your model into a glide and tweaking the elevon position to get a nice glide. You can also add a little more up elevon on one side than the other to get a circling glide.

When your rocket reaches apogee and ejection activates your glider, it will tumble a bit until it stabilizes in a nose-down flight path. It will then descend until the elevons (the ones above, the pre-set-for-glide ones) begin to pitch the glider into horizontal flight.

With contest boost-gliders this transition takes place fairly quickly, within a second or so. With a big scale shuttle model it will take longer, and you may use up most of your altitude before it stabilizes into a nice glide.

Just out of curiousity, what did you build your rocket out of that it weighs a pound? Can you make another build attempt and try to keep it "cleaner" than the first time?
 
Originally posted by powderburner
Just out of curiousity, what did you build your rocket out of that it weighs a pound?
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well, the shuttle and stack is made of posterboard. that actually weighs less than a pound, but i planed to fill the bottom dome of the external tank with water and dry ice as the fog will spew through straws that connect the orbiter to the thank for a "main engine ignition" effect.
 
Originally posted by ben
I am working on a shuttle on a little bigger scale and are making it alot more scale with a launck pad, assembly building, and the shuttle Discovery will be remotely glided home check out the thread.......

https://www.rocketryforum.com/showthread.php?s=&threadid=19264
Click to expand...

so you're who jake is working with? that's cool! i can't wait to see pictures. i'll post my pix tonight, and i'll also post on my yahoo! group. here's the link if you want to join... https://groups.yahoo.com/group/NASA-land/
i considered doing mine R/C but, new orleans doesn't have much room and my grandfather doesn't won't to travel too far, so i'm stuck with launching behind the recreation center, meaning that my shuttle would have to be smaller ( the size it is now). also, i plan to do a delta 4 heavy, saturn v, and an X33!
 
A few notes:

An 18 ounce model is going to be seriously underpowered on 2 C6s.

100 ft is quite low. Are you sure you'll be able to get a recovery system out before it comes back down? Are you sure it will even fly fast enough to be stable?

Rocksim says a low drag (eg, not your shuttle) 18 ounce model will reach about 100 ft, arc over, and head down for quite a while before deploying the chute even on a C6-3. This may destroy the recovery system, depending on the recovery components. It will leave the launch rod at a very low velocity, and already barely stable model will probobly be unstable.

I'd suggest you scrap the smoke generation idea. Its simply not worth the weight penalty. Remember that the SSMEs produce very little if any smoke. White Lighting motors in the SRBs will produce very realistic smoke trails, however. You'll want a strong and heavy (compared to Estes stuff) rocket for those, though, unless you want to go for a very long walk.



One thing I must ask, you have flown 'normal' rockets before, yes?

You said you had two years of experiance, but then you 'discovered' ejection charges. Someone who has flown for 2 years should know them very well...

The reason I ask is I sometimes see those new to rocketry planning grandose ideas that will probobly not work, and may end up getting someone hurt. Start simple. You'll realize the complex designs aren't that easy, and take quite a bit of thought and planning.
 
Originally posted by Nerull

100 ft is quite low. Are you sure you'll be able to get a recovery system out before it comes back down? Are you sure it will even fly fast enough to be stable?

Rocksim says a low drag (eg, not your shuttle) 18 ounce model will reach about 100 ft, arc over, and head down for quite a while before deploying the chute even on a C6-3.
Click to expand...

How about for 131 feet on the same two C6s?
 
EXPECTE SHUTTLE STATUS
Total launch mass = 1133.0 g (2.5 lbs.)
Diameter = 228.6 millimeters (9 inches)
2 engines of type Estes E9
Flight duration=7.7 seconds
Max altitude = 40.25 meters (132.0 ft) at 4.4 seconds.
Turn over at 4.5 seconds
Impact downrange 6.6 meters at 20.5 m/s.

i'm rebuilding my shuttle and it should be about 30 inches tall. i shall soon see how it works out...
 
You don't plan to recover the stack?

At that launch rod velocity, I would be very worried about stability. The shuttle stack isn't very stable as it is, and its going to be going very slowly on those motors.

Also, a friend of mine studying aerospace engineering said your dry ice thing will likely get you a block of water ice inside the ET, instead of the smoke you want. I'd sugguest testing that before building the shuttle for it.
 
Originally posted by Nerull
You don't plan to recover the stack?

At that launch rod velocity, I would be very worried about stability. The shuttle stack isn't very stable as it is, and its going to be going very slowly on those motors.

Also, a friend of mine studying aerospace engineering said your dry ice thing will likely get you a block of water ice inside the ET, instead of the smoke you want. I'd sugguest testing that before building the shuttle for it.
Click to expand...

i'm recovering the stack. i'm using e-9s with a 4 second delay. also, i'll test the dry ice...thanks for the heads up, though...;)
 
You are aware the delay is measured from burnout, not ignition, right? Your delay is going to fire a significant portion of the way back down, it may even go off after your shuttle stack has slammed into the ground, with that low altitude.

EDIT: It will take about 2.5 seconds for an object to freefall from 100 ft. You are also going to have about 2.5 seconds of extra delay, where your model will be freefalling (wRASP says optimum delay is 1.5 seconds). There is a good chance your stack is going to slam into the ground before the parachute deploys...assuming its even stable. Every shuttle stack i've seen has been barely stable at good speeds, yours is going incredibly slow. Fins don't function at low speeds. At T+1 second, its going to be just 15 ft in the air! For a comparison, an Estes Alpha 3, loaded with an A8 for a 250 ft flight, will be over 100 ft. in that time.
 
This rocket NEEDS F21's. 2 E9's will make it severely underpowered, and it will have a difficult time even clearing the launch rod. One E9-4 has a difficult time lifting a club member's Phoenix off the pad - it is 9.5oz loaded. Yours would be a shuttle (a less stable design) with around 20oz/motor at liftoff, creating some interesting instability problems. I would reccomend F21's - those would boost liftoff thrust to 20lbs (both motors combined). This would allow the shuttle to get up to a safe speed in time. It would also give you a nice AT WL flame - very scale.
 
Total launch mass = 510 g (1 lb.)
Diameter = 228.6 millimeters (9 inches)
2 engines of type Estes D12-3
Flight duration=8.6 seconds.
Max altitude = 44.09 meters (144.7 ft) at 3.2 seconds.
Turn over at 3.2 seconds
Impact downrange=3.3 meters at 9.2 m/s.


the thing is that, the only thing that i'm worried about is losing my orbiter. i don't think there's a way to predict how far from the pad it will glide. besides, i don't want to end up causing any car accidents if it lands in the street. other than that, i could let this thing go wherever! but then again, i could bend the elevons so that it either does a helix or does a series of nosedives on the way down...

also, i'm only going to use dry ice for the Beanie cap (GOX vent hood) on the launch pad. i will use Rapier L2s in the main engines.
you stick the fuse in the Rapier motor and light it with a match right? (probably a dumb question...):confused: :rolleyes:
 
Originally posted by spaceshuttle
the thing is that, the only thing that i'm worried about is losing my orbiter. i don't think there's a way to predict how far from the pad it will glide. besides, i don't want to end up causing any car accidents if it lands in the street. other than that, i could let this thing go wherever! but then again, i could bend the elevons so that it either does a helix or does a series of nosedives on the way down...
Click to expand...

Unless you're an aerodynamics expert or just plain lucky, you don't have to worry about losing a shuttle-type glider. You'll be lucky if it actually glides without spiraling in. More than likely it will do either that or flutter in like a leaf. I really suggest an email or phone conversation with George Gassaway.
https://members.aol.com/narshuttle/shuttlehome.htm


also, i'm only going to use dry ice for the Beanie cap (GOX vent hood) on the launch pad. i will use Rapier L2s in the main engines.
you stick the fuse in the Rapier motor and light it with a match right? (probably a dumb question...):confused: :rolleyes:
Click to expand...

If you were using the Rapiers in a hand-launched very light model, yea, you can light them with a match. However, if you're concerned with realism, you'll want to electrically ignite those as well using a separate launch system. The problem there is what sort of release mechanism are you going to use for the shuttle, and will it hold on the pad for even the minimal thrust of the Rapiers?
 
Originally posted by spaceshuttle
Total launch mass = 510 g (1 lb.)
Diameter = 228.6 millimeters (9 inches)
2 engines of type Estes D12-3
Flight duration=8.6 seconds.
Max altitude = 44.09 meters (144.7 ft) at 3.2 seconds.
Turn over at 3.2 seconds
Impact downrange=3.3 meters at 9.2 m/s.


the thing is that, the only thing that i'm worried about is losing my orbiter. i don't think there's a way to predict how far from the pad it will glide. besides, i don't want to end up causing any car accidents if it lands in the street. other than that, i could let this thing go wherever! but then again, i could bend the elevons so that it either does a helix or does a series of nosedives on the way down...

also, i'm only going to use dry ice for the Beanie cap (GOX vent hood) on the launch pad. i will use Rapier L2s in the main engines.
you stick the fuse in the Rapier motor and light it with a match right? (probably a dumb question...):confused: :rolleyes:
Click to expand...

OK. 1lb and 2 D12's can at least get off the pad safely (it's your first design that even has a chance of that). Now you need to make sure it is as symmetrical and even as possible. If anything is off, your model will do some spectacular spirals 10' up. As for loosing the glider - the best glide I have EVER seen on a space shuttle was one club member's Estes shuttle stack - his shuttle came down about 30 yards from the pad (it was released 144' up). Yours will probably not even glide that well. You need have no fear of yours getting lost (I'd be more worried that it wouldn't glide than that it would glide too well)
 
or better yet...

EXPECTED SHUTTLE STATUS
Total launch mass = 250.0 g (.5 lbs. 0.88 oz.)
Diameter = 152.4 millimeters (6 inches)
2 engines of type Estes C6-3
Flight duration=10.8 seconds.
Max altitude = 50.36 meters (165.2 ft) at 3.2 seconds.
Turn over at 3.2 seconds
Chute deployment at 2.24 m/S, shock = 1.09 g.
Impact downrange 3.4 meters at 7.1 m/s.
Peak speed = 30.92 meters per second (69.2 MPH).
Maximum acceleration = 9.86 g.
Launch angle = 2.00 degrees from vertical.
Ejection=3 seconds after launch.
Parachute diameter = 304 millimeters (12 inches).

i'm going back to my original 20"x 6" design.
 
odd question...
if i were to cut a sparkler candle in half, would it still work?
 

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