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Micromeister

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Was that a COOL Looking flight or what! All the nay saying & controversy aside the flight looked pretty impressive to me. Super neat & some Great Pics....Now to Scale one that works LOL!
OH man.. Short, Fat rockets with tiny fins...Should be interesting.
 
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dr wogz

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A lot of fire!

A lot of 'chutes!!
(Reminds me of them Russian nesting dolls..) it just kept getting smaller & smaller, with more & more peices falling away!

tres cool!!
 

luke strawwalker

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This should certainly be a lot easier to build on a model-- four little MLAS motor "bumps" on the side of a capsule instead of a huge tower with nozzles sticking out...

Thank goodness Ares I at least has a smooth cylinder LAS now instead of those latticework towers like Apollo and Mercury...

Course that reduces the challenge of the build too... :dark:

Later! OL JR :)
 

sylvie369

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This should certainly be a lot easier to build on a model-- four little MLAS motor "bumps" on the side of a capsule instead of a huge tower with nozzles sticking out...
And two altimeters, each with three event outputs, and if I'm counting correctly, 9 parachutes, including one rear deployment.

I'll bet George Gassaway could do it.
 

jpaw33

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Shrox and Quest have it in the works and say it's on the fasttrax to production. Yee-haa!!!
 

wilsotr

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Actually, at least one model has already been done .... though I admit to having had a bit of an advantage. :)

Attached pic is of the 1:20 scale MLAS (micro-MLAS, or uMLAS, as we started calling it) as displayed at one of the full-scale-MLAS technical reviews. Intent was to fly it ahead of the real thing, but as luck would have it, I didn't get the chance. So first flight will probably be at a SEVRA or MDRA launch in the near future.

uMLAS was designed to fly on a cluster of three G80's. Boost skirt (the "first stage") drag separates at burnout, Coast Skirt ("second stage") is separated and recovered by a rear-ejecting chute, and the Forward Fairing and CM are recovered on independent chutes. Coast Skirt and CM have redundant timers to make all this happen (total of 4 ... Xavien and PerfectFlite). The CM has a rear-looking BoosterVision camera as an added bonus. Forward Fairing and CM were beautifully done by Gordon Agnello, aka "Sandman", and those black-and-white retro-looking chutes are silk, custom-made by a friend.

And yes, stability is marginal. Very. But so was that of the real thing. :) Attached is the Rocksim file ... interestingly, the CP location predicted by RockSim falls almost exactly at the point predicted by wind tunnel tests of the full-scale MLAS. It takes about 3 pounds of ballast to pull the CG ahead of the CP ... uMLAS is heavy and will be piggy off the pad. Definitely want to fly on a "no-wind" day.

I'll post build pics and drawings when I have a chance. Still recovering from several very LONG work weeks ....

tw

IMG_5955.jpg


View attachment uMLAS.rkt
 

rstaff3

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Very cool, thanks for sharing. Hope I get to see it, in flight or otherwise, at an MDRA event.
 

Gus

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Sandman, Peter Alway, and I were guests at the launch.

I posted a report of our trip on YORF at: http://forums.rocketshoppe.com/showthread.php?t=5453&page=2

Tim, thanks for posting the Rocksim. I know Tim at Apogee works hard to make the program accurate but in this case I have to question whether the reason the CP is so close to the actual article is that the vehicle is so short there just aren't many places for it to go. ;) Kind of like asking somebody from Rhode Island if they live near Providence.
 

wilsotr

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I know Tim at Apogee works hard to make the program accurate but in this case I have to question whether the reason the CP is so close to the actual article is that the vehicle is so short there just aren't many places for it to go. ;) Kind of like asking somebody from Rhode Island if they live near Providence.
Actually, Barrowman puts the CP significantly further forward than the RockSim calcs do ... you can flip the "Barrowman vs. RockSim" switch in the program and see the difference. So Tim's RS algorithm is pretty good. I got a kick out of pointing out to our aero guys that my $120 model rocket code yielded the same answer as their much-more-expensive-and-time-consuming wind tunnel tests. They didn't see the humor.
 

sandman

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Actually, Barrowman puts the CP significantly further forward than the RockSim calcs do ... you can flip the "Barrowman vs. RockSim" switch in the program and see the difference. So Tim's RS algorithm is pretty good. I got a kick out of pointing out to our aero guys that my $120 model rocket code yielded the same answer as their much-more-expensive-and-time-consuming wind tunnel tests. They didn't see the humor.

ROTFLMAO!!!!!
 

Sandy H.

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Did you say 3 pounds of nose weight!?!?! What is the lift off weight?

I watched the video and thought to myself that if I ever pulled off a launch of a conventional length ratio rocket with that many events successfully, I would have to quit the hobby as I would have max'd out what could be done.

I hope the engineering data meant something and that it is a positive step forward. Either way, it was a great video to watch!

What were the rough motor specs? I don't need to know specifics, but a letter followed by a number to help me understand what I saw would be cool.

Sandy.
 

wilsotr

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Did you say 3 pounds of nose weight!?!?! What is the lift off weight?

I watched the video and thought to myself that if I ever pulled off a launch of a conventional length ratio rocket with that many events successfully, I would have to quit the hobby as I would have max'd out what could be done.

I hope the engineering data meant something and that it is a positive step forward. Either way, it was a great video to watch!

What were the rough motor specs? I don't need to know specifics, but a letter followed by a number to help me understand what I saw would be cool.

Sandy.
Yep ... 3 pounds for the uMLAS model. It weighs about 12.5 pounds, as-built. The real MLAS weighed in at about 47,000 pounds and carried its own ballast in the "fake" motor troughs (the four blisters on the outside of the Forward Fairing where motors would be placed in an operational system). The motors were surplus Navy MK-70's ... same ones used in earlier versions of the Standard ARM and in Terrier sounding rocket boosters. MLAS used a cluster of four inside the Boost Skirt, canted so the thrust axes would align through the vehicle centerline. They provided about 70,000 pounds of thrust each, a total of 280,000 pounds.
 

Gus

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The motors were surplus Navy MK-70's ... same ones used in earlier versions of the Standard ARM and in Terrier sounding rocket boosters. MLAS used a cluster of four inside the Boost Skirt, canted so the thrust axes would align through the vehicle centerline. They provided about 70,000 pounds of thrust each, a total of 280,000 pounds.
I read somewhere that the motors used were manufactured in 1988. I have no idea what the expected life of such motors is but did you have to do anything special to ensure they were still good?

And in model rocketry terms each of the four motors would have been roughly an R-54,000.
 
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wilsotr

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I read somewhere that the motors used were manufactured in 1988. I have no idea what the expected life of such motors is but did you have to do anything special to ensure they were still good?

And in model rocketry terms each of the four motors would have been roughly an R-54,000.
Yep ... the Indian Head Division of the Naval Surface Warfare Center static-fired a motor for us. We used the data from that test to ensure our motors -- taken from the same manufacturing lot -- would work properly. Also gathered some data on the heat flux we could expect during firing which helped us design thermal protection for the Boost Skirt.
 

stickershock23

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If anyone does a model, and wants a Mission Logo decal.

I know were to get them :D

Cool project. I feel lucky when I get one or two events to happen on "Q" let alone a dozen or so. LOL

mlas.jpg
 

shrox

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The Quest MLAS will be a sport scale model, so you won't be afraid to actually launch it and lose all the work you might put into a detail scale model. It will be pretty neat either way, I'd rather set the detailed one on display and fly the sport scale. It's amazing how grass stains get embedded in white paint.
 

sandman

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If anyone does a model, and wants a Mission Logo decal.

I know were to get them :D

I already have waterslide decals that include the MLAS logo, NASA meatball, the U.S. flag and the fin number.
 

wilsotr

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The Quest MLAS will be a sport scale model, so you won't be afraid to actually launch it and lose all the work you might put into a detail scale model. It will be pretty neat either way, I'd rather set the detailed one on display and fly the sport scale. It's amazing how grass stains get embedded in white paint.
Let us know when you guys start taking orders ......... :)
 

jcsalem

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Is it just me or does anyone else think this is over-engineered?

There are so many separations and and parachutes it seems like there are too many needless opportunities for something to go wrong. Not to mention the cost of assembling the thing. Why does MLAS require all this when the Apollo escape tower was largely just one piece?

Jim
 

georgegassaway

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The thing is, that this “Pad Abort Test”, was not a Pad Abort Test.

It was an aerodynamic test to see if the MLAS Abort design, once boosted , and once separated from its Non-MLAS rocket, would re-orient itself heat shield down once its two pilot chutes deployed.

The MLAS was NOT the 8-finned rocket part, even though lots of publicity from last week left that impression. MLAS was the nose part, and only the nose part. But they did not fly a real MLAS on top.

Had this been a real MLAS Pad Abort test, there would have been no rocket underneath, at all. The thing that is really unique about the MLAS concept is to have 4 solid engines mounted on the “sides” of the capsule cone, ignite those 4 solids, and those would pull the Orion Capsule to safety - FROM THE PAD if things went wrong that fast.

I have been somewhat confused, and at some points just plain frustrated, that they flew what they flew last week, and did not fly the real MLAS. The times that really ticked me off the most was when it was referred to as “Pad Abort” testing which it was not, whatsoever.

Now, it is sort of neat what they did fly. As a new rocket that some might want to make a model of, sure. I get that.

But I think of it as regards the space program. Considering they did NOT fly the real part of it that makes it unique, and it seems they never will, what a confusing waste. It would have been REALLY interesting to see if 4 unguided rockets on the cone of the capsule would have flown straight, or veered off badly. When I first heard of the MLAS test, a Pad Abort Test, I thought that was what they were going to test - the unique 4 solids on the capsule conical sides part, from the ground. Not boosted about a mile into the sky by a non-MLAS booster rocket, only to test out aerodynamic orientation when the pilot chutes deployed.

FWIW - attached is a comparison I made as a “what if” Apollo had done the same sort of thing as the MLAS launch last week. At left, the real Pad Abort. In middle, an Apollo if done “MLAS” style like last week.

And at the far right of it, the actual MLAS True Pad Abort that was not flown. All the above I described will make more sense, or maybe far less sense once you realize what they did not do, once you see the real MLAS on the right.

- George Gassaway

Apollo-MLAS-comparison.jpg
 
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brianc

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I have been somewhat confused, and at some points just plain frustrated, that they flew what they flew last week, and did not fly the real MLAS.
Just wait until the CROC and scaleroc discussions fire up in earnest! Is this
prototype valid for scale, sport scale, SF/F, Concept Scale (or whatever it's called this week)?

Can't wait- get the popcorn! :D
 

wilsotr

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Is it just me or does anyone else think this is over-engineered?

There are so many separations and and parachutes it seems like there are too many needless opportunities for something to go wrong. Not to mention the cost of assembling the thing. Why does MLAS require all this when the Apollo escape tower was largely just one piece?

Jim
Good observations, Jim.

MLAS was not an operational system, but a technology demonstrator. A flight abort system based on the MLAS concept would have propulsion built into the Crew Module fairing. It would have some kind of deployable aerodynamic or thrust-vector control to provide stable flight through ascent and to orient the vehicle at apogee for spacecraft separation and recovery. MLAS simulated all that with its various components ... a Boost Skirt, a Coast Skirt, and all those fins, parachutes, and flight events. An operational MLAS-type system would be "compact" and much more robust than the MLAS flight test vehicle was.
 

wilsotr

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Considering they did NOT fly the real part of it that makes it unique, and it seems they never will, what a confusing waste. It would have been REALLY interesting to see if 4 unguided rockets on the cone of the capsule would have flown straight, or veered off badly. When I first heard of the MLAS test, a Pad Abort Test, I thought that was what they were going to test - the unique 4 solids on the capsule conical sides part, from the ground. Not boosted about a mile into the sky by a non-MLAS booster rocket, only to test out aerodynamic orientation when the pilot chutes deployed.
Certainly understand the confusion, and you are correct: MLAS was not an operational abort system. It was a flight experiment intended to demonstrate key elements of such a system, specifically stable unguided flight of a fully-encapsulated CM, reorientation and stabilization at apogee, and CM separation in an attitude suitable for recovery.
 

sandman

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Certainly understand the confusion, and you are correct: MLAS was not an operational abort system. It was a flight experiment intended to demonstrate key elements of such a system, specifically stable unguided flight of a fully-encapsulated CM, reorientation and stabilization at apogee, and CM separation in an attitude suitable for recovery.
And it was way way cool!

Understand this one important fact about the flight that has been much overlooked.

It was the very first launch of anything for the Ares project.

This was an absolute first!

Nothing else for the CEV, Ares I or Ares V has flown under it's own power.

Think about it.
 
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Gus

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George,

Since the capsule in this test was accelerated to the same speed as the in-fairing motors would have provided in an off the pad abort, I would call this a pad abort test. The goal was to check stability and parachute deployment at off-the-pad speeds. Whether that boost was provided by motors in the fairing or behind the vehicle didn't really matter to check the basic concept. Since the impulse of the boost was the same as the escape motors would provide themselves if lit on the pad, I would consider this a pad abort test.

In order to ensure that the 4 in-fairing motors would all light simultaneously and burn at the same pressure, NASA envisioned a manifold that would connect all 4 motors together at their apex. Before going to the time and expense to engineer that manifold it made sense to test the aerodynamics of the fairing-capsule combination first. It makes no sense to spend the time to engineer the manifold before you prove you can keep the thing from going ass over teakettle in glide. So the boost from behind concept was a reasonable first step. Boost from behind at off-the-pad abort speeds to see if the vehicle is stable to a safe altitude and can get the chutes out.

Similarly, before going to the time and expense of developing the in-fairing-flop-down-drag-plate-fins, which have to be discardable at apogee, it made sense to simulate the same stability effect with regular fins in a discardable boost skirt first. Again, a quicker, simpler approach to getting the info you need to see if the basic design makes sense.

This flight proved the basic concept. The next step is for NASA to decide if they want to spend the time and money to develop the motor manifold and flop-fins. I imagine those two items may take as long to develop as this entire project has taken to date.

Finally, an interesting historical sidelight. I know some of the astronauts referred to the entire Apollo LES test series, PAs and LJIIS, collectively as "pad abort tests." Anything that used the escape tower rocket was called a "pad abort" as opposed to the aborts scenarios which they practiced for post tower jettison. Whether the abort actually occurred on the launch pad or in early boost made no difference. If the escape tower was used it was a "pad abort".
 
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