X-37B/Atlas V Launch Apr 22

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trailrider

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Presumably, in the intervening years, they've got the software and sensors refined a bit. With all the UAV's and UCAV's now operational, they ought to have things worked out...at least once they get the beast de-orbited and re-entered.
 
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job1207

Guest
With Shuttle guy watching, I don't mind saying that at some point in the last few years they did come up with a kit to allow the STS to land on its own. I believe it was after the last incident.

http://www.spaceref.com/news/viewsr.html?pid=10518

http://science.slashdot.org/article.pl? ... 30/0458246

So this vehicle obviously has the benefit of the STS experience. I am sure that they did it a bit more elegantly than providing a 26 foot cable to link two systems.

I am wondering about advances in Heat Shield technology. I have not seen them come up with anything new. It seems that this vehicle has a Heat Shield from the same family of products as the STS.
 
V

vulture4

Guest
The STS-3 commander should have simply let the autopilot land the Shuttle. Taking over at the last minute did not add safety. That error effectively killed the Shuttle autoland capability because the common conclusion was that the rough landing was a failure of the autoland system, when in reality it was a human factors problem. Because each commander has so few landing opportunities and the psychological reward of achieving a perfect landing is so important in aviation, no astronaut would be willing to make an automatic landing.

From a purely technical standpoint this reluctance is absurd. Every modern airliner has autoland and you have all probably been passengers in an automatic landing, trusting your lives to the computer when the aircraft is too low for the pilot to correct for a failure. From the point of view of human factors, flying the touchdown is a completely mechanical task and is much more suited to an automated system than a human pilot. Look what happened to to President of Poland recently in a landing trusted to a human pilot.

This isn't to say the commander doesn't have a critical role, but like the captain of a ship, he/she has more important things to do than turning the wheel. Nevertheless, we need the X-37 to demonstrate autoland of a space vehicle because no human pilot (for reasons of psychology, not capability) is willing to accept the task.
 
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job1207

Guest
According to my reading, that was not the plan V.

SG seemed to have all of the details on the issue. They knew it was a human factors problem from the beginning.

With ALL of the Shuttle issues, one thing comes through, as always. While the platform is JUST coming into its own, a failure to think things through kept the STS from being anything more than an experimental test bed, until I would say recently. It is notable that after they began to check the TPS carefully after launch, they had a round of changed procedures for applying the TPS, as well.

The main problem was that they were not treating the STS as an experimental test bed. With an experimental test bed, you fly and go back to the drawing board, improving as you go. I really wish they did that before the incidents.

Net, though, after all these years, a LOWER cost STS is not in sight, so, it is time to go back to the old way of getting to space.

This Air Force spy plane is good in that it can continue the reusable space plane research. Soon the Air Force will have a fleet of two. ( hopefully )
 
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stevekk

Guest
Its unfortunate that NASA isn't leading this basic research mission. I see that as one of their core missions, but I guess it's a lot easier to find a few spare billions in the defense department than it is within NASA.

I read somewhere that the Shuttle was designed for 100 flights, but that was with a much quicker turnaround between flights. They never thought it would take 30 years just to get 30 flights off the ground.

perhaps this X-37 can fulfill the shuttle's promise of a 2-week turnaround between missions. I assume we have learned a few lessons in the last 30-40 years about TPS technology also.
 
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shuttle_guy

Guest
refer the STS-3 landing. Here is the commander's version of the landing: from:

http://www.collectspace.com/ubb/Forum30 ... 00774.html

Alrighty, thanks to Al getting ahold of Jack and Jack being willing to tell his side of the story. That can be a problem with trying to relay stuff in the second person when I don't have the recorder running as things can get lost in the translation. Indeed I again admit I was the one that left the impression that Jack and Chris Kraft might have had a little "discussion" about this after the flight when indeed Jack made no mention of such an event taking place. As such, here it is from Jack's perspective. Of course I do admit I didn't really HAVE a way to get in touch with Jack before posting this (no excuse though). But I am glad he is able to set the record straight on it since this topic does seem to come up often. So here it is, straight from Jack's keyboard (and sincerest thanks to him for giving permission to post this and Al for asking him to do so).
Jay's account of the STS-3 approach and landing is only partially correct. He should have asked me to review his report before posting it. The most objectionable part insinuates Chris Kraft is unreasonable and that he ended my flight career because he was unhappy with the landing. That kind of speculation is out of bounds and publishing such rumors is poor journalism. Chris is objective, candid, an original space pioneer, and a dynamic, effective leader.

Reports and rumors about how the STS-3 approach was flown and what "must have occurred" (but didn't) have come and gone over the years. Interestingly, none of these reports and rumors was preceded by asking me what happened, except for the recent conversation with Jay. Incidentally, Jay and I did not discuss anything about Chris Kraft's reaction to STS-3, as alleged in his commentary.


The fact is that Chris Kraft and I have always enjoyed cordial relations both professionally and socially. In a private, post-mission conversation, he did not criticize any part of STS-3, including the landing which was within shuttle limits. He was pleased with the overall outcome of the mission and brushed off the landing as acceptable under the circumstances. I consider Chris as a personal mentor and friend in my career at NASA, and he never put me under the gun. It was made clear to me that I could command another flight, but after proceeding with early training on a flight that was about two years downstream, I decided it was time to be moving on with the inevitable next phases of life's journey before it was too late to get started. Had I been able to fly again sooner I probably would have stayed around to do so, but I made the right choice at the time and have never looked back. Life is good!


The STS-3 approach problem is simply explained by stating that the auto system, while it correctly controlled the nose of the ship on the outer glide-slope, through the preflare, and on the inner glide slope, it did a poor job of modulating the speed brakes to control the airspeed on the outer glide-slope. The auto system also fully closed the speed brakes 1,500 feet before I would have done so manually. This resulted in a substantially higher speed coming out of preflare and being closer to the ground (further down the inner glide-slope) when the gear were lowered procedurally based on airspeed (270 knots) rather than altitude (gear down was changed to 400 feet after that). I took back manual control when stabilized on the inner glide-slope by depressing the "Manual" button on the eye-brow panel; not by moving the hand-controller out of detent, as has been rumored. It was mandatory to land in manual control because the landing software was not yet fully developed and tested.


The auto system also lined-up the shuttle slightly to the right of centerline, which I decided not to correct that close to landing. In essence, the auto system did not fly the approach I would have flown manually, but it was not unsafe. So my job became one of salvaging a less than perfect approach, which I did, but not as well as I would have preferred. Further, we did get the data required by the autoland test objective, and we also proved the well-worn adage of our first flight instructors; 'To make a good landing you must fly a good approach'. Incidentally, we never experienced this speedbrake control problem in simulation. The simulators always modulated the speedbrakes in small increments to control speed perfectly. If the flight software had been installed in the simulators we would have been ready for this problem, except that we would have rejected the autoland test objective altogether until the flight software was capable of smooth speed control. We vigorously insisted on simulating with flight software installed, but this requirement 'fell through the crack' somehow in the fixed and motion-base simulators as well as the Shuttle Training Aircraft. Unfortunately, we didn't know of this oversight until we flew STS-3.


With respect to the "wheelie" right after touchdown, the nose began to drop before aerodynamic braking was complete at 160 knots, so I tried to hold it off with a short nose-up pulse on the hand-controller. The nose did not react quickly enough for me, so I gave it another short nose-up pulse. This caused the nose to rise rapidly whereupon I lowered the nose to the runway manually. I was told later there was an instability in the longitudinal control software in that landing configuration causing the unexpected pitch-up. Perhaps there was. In any case, we learned a lot with no harm done; that's why we do test flights. And that's why I have moved beyond the rumors and speculation on this whole subject, and that's why it was of little consequence to Chris Kraft.


The autoland system was scuttled after that experience because it was not "certifiable" in the aviation sense of "certification". Moreover, our experience implied that if the autoland failed close to the ground, it would force a "late takeover" in a possibly unrecoverable attitude. Thus, it would be better to not fly the autoland system down to a position that would be potentially unrecoverable. I think some sort of autoland system has been installed in case they would want to try to recover a damaged shuttle, incapable of safe reentry (like Columbia) that was abandoned at the ISS, the crew having been ferried home from the ISS in a rescue shuttle.
 
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shuttle_guy

Guest
I have a plot of the STS-3 landing data showing air speed. angle of attack. hand controller inputs ets which is very interesting. It was drawn at White Sands while I was there for the landing. How do I attach a picture to a post?
 
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EarthlingX

Guest
shuttle_guy":278xikc8 said:
I have a plot of the STS-3 landing data showing air speed. angle of attack. hand controller inputs ets which is very interesting. It was drawn at White Sands while I was there for the landing. How do I attach a picture to a post?
If it is on the net, copy image location/URL to the post, and enclose it with image tags, like this :
color]location%20of%20image%20-%20URL[color=

Code:
[img]http://t1.gstatic.com/images?q=tbn:1Ewh4-y4EH8IaM:http://www.wired.com/images_blogs/photos/uncategorized/2008/08/07/x37b.jpg[/img]
which gives :
images


If it's not, you have to upload it on the Net first. I use Photobucket.

You can also link hi-res image, by enclosing tagged link with url tag, like this :
[url=location of hi-res image]
color]location%20of%20image%20-%20URL[color=
[/url]
Code:
[url=http://www.wired.com/images_blogs/photos/uncategorized/2008/08/07/x37b.jpg][img]http://t1.gstatic.com/images?q=tbn:1Ewh4-y4EH8IaM:http://www.wired.com/images_blogs/photos/uncategorized/2008/08/07/x37b.jpg[/img][/url]
and result :


A bit more on the subject, with links here :
Relativity Calculator

Images from :
http://www.wired.com/dangerroom/2008/08/air-force-space/
 
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nimbus

Guest
Or you can send it to one of us who'll be glad to upload it to a hosting service for you, SG.
 
T

trailrider

Guest
SG:
Could you answer a question for me? In the most recent issue of Air & Space Smithsonian, there is an article about the Shuttle and various changes that were made to it over the course of the program. (Note: prior to 1986 I worked on SRB Decelerator Subsystem for Martin-Marietta, hence my curiosity about the following.)

According to the article, about 1994 "the main chute diameters were increased from 115 ft. in diameter to 136 ft."

Now, back when I was on the program, the main chutes were 136 ft. spherical canopy ribbon chutes. At the time when there were plans to replace the maraging steel boosters with filament wound, lightweight boosters, the plan was to reduce the diameter to 115 ft. Kevlar ribbon chutes. When the filament wound cases were eliminated, so were the 115 ft. chutes. My question: Did they go to the smaller chutes and then switch back? Or did the writer in A&S Smithsonian make a mistake? :?:
 
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shuttle_guy

Guest
trailrider":16cjhhm2 said:
SG:
Could you answer a question for me? In the most recent issue of Air & Space Smithsonian, there is an article about the Shuttle and various changes that were made to it over the course of the program. (Note: prior to 1986 I worked on SRB Decelerator Subsystem for Martin-Marietta, hence my curiosity about the following.)

According to the article, about 1994 "the main chute diameters were increased from 115 ft. in diameter to 136 ft."

Now, back when I was on the program, the main chutes were 136 ft. spherical canopy ribbon chutes. At the time when there were plans to replace the maraging steel boosters with filament wound, lightweight boosters, the plan was to reduce the diameter to 115 ft. Kevlar ribbon chutes. When the filament wound cases were eliminated, so were the 115 ft. chutes. My question: Did they go to the smaller chutes and then switch back? Or did the writer in A&S Smithsonian make a mistake? :?:

I believe the 'chutes were alway 135 ft diameter. I will check my sources.
 
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3488

Guest
Courtesy of shuttle_guy.

Landing profiles graphic of STS 3 Columbia way back on: Tuesday 30th March 1982.
STS3Columbialandingprofilegraphsdc.jpg


FULL RESOLUTION GRAPHIC HERE

Columbia landing at the end of STS 3 on: Tuesday 30th March 1982 @ White Sands, New Mexico. T38 Chase Planes ensure that all is well. A side note, STS 3 Columbia was the first to launch with an orange unpainted ET. Shedding the white coat of paint saved 110 KG of mass at launch.
STS-3Columbialanding.jpg


This is on topic as this shares traits with the expected landing profiles of the X-37B.

Will be great to see X37 B land. Hopefully coverage of sorts will be made available.

Andrew Brown.
 
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3488

Guest
nimbus":388l699d said:
Or you can send it to one of us who'll be glad to upload it to a hosting service for you, SG.

Hi nimbus,

I am very happy to help with this. That is quite a chart, I can understand it after looking at it for a while. :)

Andrew Brown.
 
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nimbus

Guest
Altitude, airspeed, angle of attack, and RHC. RHC is pitch input from Jack Lousma?
 
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shuttle_guy

Guest
nimbus":99ttawz0 said:
Altitude, airspeed, angle of attack, and RHC. RHC is pitch input from Jack Lousma?


Yes, that is Jack's manual flying. The RHC, of course generates roll and yaw but I only ploted pitch.
 
J

job1207

Guest
stevekk":2r7k35p8 said:
Its unfortunate that NASA isn't leading this basic research mission. I see that as one of their core missions, but I guess it's a lot easier to find a few spare billions in the defense department than it is within NASA.

I read somewhere that the Shuttle was designed for 100 flights, but that was with a much quicker turnaround between flights. They never thought it would take 30 years just to get 30 flights off the ground.

perhaps this X-37 can fulfill the shuttle's promise of a 2-week turnaround between missions. I assume we have learned a few lessons in the last 30-40 years about TPS technology also.

As far as I know, assuming that notion about TPS is incorrect. That remains the long end of the stick. Now, this is a smaller stick, since it is a smaller craft, and it is unmanned.
 
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EarthlingX

Guest
http://spaceweather.com/archive.php?view=1&day=01&month=06&year=2010
X-37B FLARES: Multiple observers are reporting "X-37B flares." When the USAF space plane flies overhead, it suddenly increases in brightness five-fold or more. Amateur astronomer Bryan Murahashi photographed the phenomenon on March 30th when the X-37B cut through the Big Dipper over San Jose, California:


Photo details: Nikon D300, 26s, f/2.8 at 24.0mm, ISO320


"The space plane brightened at least two magnitudes," says Murahashi. "It was a very neat thing to see."
 
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shuttle_guy

Guest
job1207":3svdzonz said:
stevekk":3svdzonz said:
I read somewhere that the Shuttle was designed for 100 flights, but that was with a much quicker turnaround between flights. They never thought it would take 30 years just to get 30 flights off the ground.

.

Yes the Orbiter is designed for 100 flight. BTW we have launched 132 flight in slightly less that 30 years.
 
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shuttle_guy

Guest
EarthlingX":feu474rv said:
http://spaceweather.com/archive.php?view=1&day=01&month=06&year=2010
X-37B FLARES: Multiple observers are reporting "X-37B flares." When the USAF space plane flies overhead, it suddenly increases in brightness five-fold or more. Amateur astronomer Bryan Murahashi photographed the phenomenon on March 30th when the X-37B cut through the Big Dipper over San Jose, California:


Photo details: Nikon D300, 26s, f/2.8 at 24.0mm, ISO320


"The space plane brightened at least two magnitudes," says Murahashi. "It was a very neat thing to see."

This is probably due to attitude changes (hopefully commanded attitude changes).
 
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nimbus

Guest
And for anyone curious, RHC stands for rotational hand controller. It sounds like a yoke, but it appears to be more of a twisty joystick.
4660482252_03069f8bb4_o.gif
 
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stevekk

Guest
shuttle_guy":kpd89vmc said:
job1207":kpd89vmc said:
stevekk":kpd89vmc said:
I read somewhere that the Shuttle was designed for 100 flights, but that was with a much quicker turnaround between flights. They never thought it would take 30 years just to get 30 flights off the ground.

.

Yes the Orbiter is designed for 100 flight. BTW we have launched 132 flight in slightly less that 30 years.

I meant 30 flights for each shuttle.

How many missions has Atlantis flown since it's last OMDP ? Probably not more than 10 or 11 in the last 5 years, right ? From what I remember, each shuttle really gets stripped down and almost completely rebuilt due to the required inspections and upgrades they perform. It's probably would have been more cost effective to just build a replacement every 5 years. What would a new shuttle cost, assuming parts were available, 2 - 3 billion ?
 
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stevekk

Guest
shuttle_guy":2acn5u71 said:
EarthlingX":2acn5u71 said:
http://spaceweather.com/archive.php?view=1&day=01&month=06&year=2010
X-37B FLARES: Multiple observers are reporting "X-37B flares." When the USAF space plane flies overhead, it suddenly increases in brightness five-fold or more. Amateur astronomer Bryan Murahashi photographed the phenomenon on March 30th when the X-37B cut through the Big Dipper over San Jose, California:


Photo details: Nikon D300, 26s, f/2.8 at 24.0mm, ISO320


"The space plane brightened at least two magnitudes," says Murahashi. "It was a very neat thing to see."

This is probably due to attitude changes (hopefully commanded attitude changes).

Are these flares similar to iridium flares ?

I guess if we are trying to build a quickly deployable sat to spy on our enemies in the Mideast and Korea, it should be a little harder to find and/or predict when it is crossing overhead.
 
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nimbus

Guest
nimbus":3pjd1ilh said:
twisty joystick.
Shuttle Guy - Why go with a twisty joystick instead of conventional 2 axis joystick + rudder pedals? What controls are the CDR/pilot's feet and other hand using meanwhile?
 
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scottb50

Guest
nimbus":2oxgmopi said:
nimbus":2oxgmopi said:
twisty joystick.
Shuttle Guy - Why go with a twisty joystick instead of conventional 2 axis joystick + rudder pedals? What controls are the CDR/pilot's feet and other hand using meanwhile?

Rudder pedals are more traditional then needed, the Ercoupe didn't have any and has flown just fine for nearly 70 years. In pretty much every jet rudder pedals are seldom used, except in an engine out scenario, not something you would see on either the Shuttle or a single engine aircraft.

With the Shuttle controller you still have yaw control, if needed. Two brake pedals would be nice though, that might come in handy for a tight turn or in a windy landing. Pitch, roll and yaw are the primary axis in flight and how you control them is what is important. In Space you also need to move along the axis, in docking you need to move along the X, Y and Z axis as well as around them to match adapter orientations.
 
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