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The Bar / Re: Aft-strakes/Back-porches
« Last post by PaulMM (Overscan) on Today at 11:53:37 am »
Steve Pace's book on the X-29 gives a little more detail on the use of aft strake controls. On the X-29 they were especially used in low speed flight to augment the canards in pitch control.

The close-coupled canards on the X-29 are relatively close to the centre of lift so their pitch authority is less than it could be.
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Military / Re: CSBA "Third Offset" paper
« Last post by sferrin on Today at 10:22:20 am »
With commercial satellite imagery, computer learns to quickly find missile sites in China

Quote
WASHINGTON — For all the hype and promise around artificial intelligence and machine learning technologies in military applications, it always comes down to what specifically can be done with it.

The industry keeps rolling out new gee-whiz artificial intelligence tools but the defense and intelligence communities still are trying to figure out how to use them and whether they really work as promised.

According to a new study, there is one area where deep machine learning algorithms can definitely help the government, and that is to analyze satellite imagery.

http://spacenews.com/with-commercial-satellite-imagery-computer-learns-to-quickly-find-missile-sites-in-china/

"Paging SOC. . ."  ;)
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Military / Re: CSBA "Third Offset" paper
« Last post by Flyaway on Today at 10:12:08 am »
With commercial satellite imagery, computer learns to quickly find missile sites in China

Quote
WASHINGTON — For all the hype and promise around artificial intelligence and machine learning technologies in military applications, it always comes down to what specifically can be done with it.

The industry keeps rolling out new gee-whiz artificial intelligence tools but the defense and intelligence communities still are trying to figure out how to use them and whether they really work as promised.

According to a new study, there is one area where deep machine learning algorithms can definitely help the government, and that is to analyze satellite imagery.

http://spacenews.com/with-commercial-satellite-imagery-computer-learns-to-quickly-find-missile-sites-in-china/
4
Military / Re: Standard SM-3 News & Dev.
« Last post by sferrin on Today at 10:02:19 am »
I sometimes wonder if there isn't a confusion in these statements between making the intercept at 1000 km or being able to intercept targets whose trajectories have a max altitude of 1000 km.  Very big difference there and one easily lost on copy writers, especially in translation.

Defining a target by how high the peak of its trajectory is seems an odd way of doing it.  Generally they define them by range.  Consider the following:

https://www.aspistrategist.org.au/ballistic-missiles-%C2%BD-rule/

"The physics of space security: a reference manual (which can be downloaded here). In their chapter on space launches, the authors take the reader through what’s called the ‘½ rule’.

I'm not talking about max potential altitude but max ordinal in a normal flight.  But I may have my numbers wrong -- I was thinking that a max ordinal of 1000 km would be right around the typical for IRBMs, which should be in SM-3 Block II's wheelhouse.

Don't know.  It's not as simple as a purely ballistic arc as a lot more comes into play as I'm sure you're aware. (Drag on both ends of the trajectory, curvature and rotation of the earth, local gravity strength along the flight path, whether you have to have the most energy efficient trajectory, etc.. ) SM-3 isn't trying to hit the target at it's apogee anyway. *shrugs*
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Military / Re: Standard SM-3 News & Dev.
« Last post by TomS on Today at 09:32:32 am »
I sometimes wonder if there isn't a confusion in these statements between making the intercept at 1000 km or being able to intercept targets whose trajectories have a max altitude of 1000 km.  Very big difference there and one easily lost on copy writers, especially in translation.

Defining a target by how high the peak of its trajectory is seems an odd way of doing it.  Generally they define them by range.  Consider the following:

https://www.aspistrategist.org.au/ballistic-missiles-%C2%BD-rule/

"The physics of space security: a reference manual (which can be downloaded here). In their chapter on space launches, the authors take the reader through what’s called the ‘½ rule’.

I'm not talking about max potential altitude but max ordinal in a normal flight.  But I may have my numbers wrong -- I was thinking that a max ordinal of 1000 km would be right around the typical for IRBMs, which should be in SM-3 Block II's wheelhouse.
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Military / Re: Standard SM-3 News & Dev.
« Last post by sferrin on Today at 08:11:25 am »
I sometimes wonder if there isn't a confusion in these statements between making the intercept at 1000 km or being able to intercept targets whose trajectories have a max altitude of 1000 km.  Very big difference there and one easily lost on copy writers, especially in translation.

Defining a target by how high the peak of its trajectory is seems an odd way of doing it.  Generally they define them by range.  Consider the following:

https://www.aspistrategist.org.au/ballistic-missiles-%C2%BD-rule/

"The physics of space security: a reference manual (which can be downloaded here). In their chapter on space launches, the authors take the reader through what’s called the ‘½ rule’.


‘A useful rule of thumb is that a ballistic missile that can launch a given payload to a maximum range R on the Earth can launch that same payload vertically to an altitude of roughly R/2. This relation is exact in the case of a flat Earth and therefore holds for missiles with ranges up to a couple thousand kilometers (the Earth appears essentially flat over those distances, which are small compared to the radius of the Earth). But the rule continues to hold approximately for even intercontinental range missiles.’

Broadly, the rule states that if a missile is fired straight upwards into space, it will achieve an altitude of ½ its maximum range. A Scud missile with a maximum range of 300 km, for example, would—if fired straight up—reach an altitude of 150 km before falling back to earth."


This would equate to a missile of only 2000km range, which even SM-3 Block I is easily capable of dealing with.

(edit: On the other hand, I recall MMIII only reaching about 700 miles altitude on it's way to a target several thousand miles away so who knows for sure?)
7
Military / Re: Standard SM-3 News & Dev.
« Last post by TomS on Today at 06:47:27 am »
I sometimes wonder if there isn't a confusion in these statements between making the intercept at 1000 km or being able to intercept targets whose trajectories have a max altitude of 1000 km.  Very big difference there and one easily lost on copy writers, especially in translation.
8
Military / Re: Standard SM-3 News & Dev.
« Last post by sferrin on Today at 06:38:03 am »
Japan may add SM-6 to Aegis Ashore

http://www.defense-aerospace.com/articles-view/release/3/187756/japan-may-add-sm_6-to-aegis-ashore.html

Thought this bit was interesting:

"The government intends to introduce two Aegis Ashore systems in Japan by around fiscal 2023 as part of the effort to boost the nation’s missile defenses.

 These would be equipped with SM-3 Block IIA missiles, a new interceptor being jointly developed by Japan and the United States with the capacity to intercept ballistic missiles at altitudes exceeding 1,000 kilometers.

 The government is also considering equipping the systems with SM-6 anti-air missiles, which are multifunction interceptors that also can take down cruise missiles."

Lots of "interesting" satellites below 650 miles or so.
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