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22 hours ago, LostCosmonaut said:

A topic that came up on discord the other day

 

The USAF is starting work on upgrading the external pylons on the B-52 to carry 20,000 lb weapons (currently 5,000 lb is limit); https://www.fbo.gov/index?s=opportunity&mode=form&id=f8e2bdc27362d841b9d6cc76699e3f7d&tab=core&_cview=0

 

There isn't much in the Air Force's inventory that fits into the 5k-20k weight category. The GBU-28 is 5,000 lb, the AGM-86 and AGM-158 are both significantly smaller. On the other end of the scale, the GBU-57 MOP is over 30,000 lb, and wouldn't fit even on the upgrade pylons (additionally, it's unlikely the B-52 would be fitted to carry new freefall bombs, such a capability would be virtually useless against anyone with air defenses).

 

The new weapon this capability is being designed for is likely some sort of cruise missile. While existing American weapons are under 5,000 lb, there are larger ones; the Kh-22 is over 12,000 lb, while the P-270 is almost 10,000 lb. So, it is possible that the USAF is developing a new high performance, long range missile, likely with significantly higher performance than the subsonic AGM-86 and AGM-158.

 

One more interesting line of thought is that the US is developing a counterpart to the new Russian Kh-47. The Kh-47, also known as Kinzhal, is an air launched ballistic missile, comparable in size to the 9K270 Iskander tactical ballistic missile.

 

1280px-2018_Moscow_Victory_Day_Parade_66

 

(User @LoooSeR on this site has posted about the missile before in this thread and the aerospace pictures thread).

 

Addition of such a missile to the US arsenal would represent a new and unique capability; the US (to my knowledge) has not dabbled in ALBMs since the abortive AGM-87 Skybolt (Which had the side effect of thoroughly fucking up British nuclear procurement and led to them getting Polaris and boats with licensed S5Ws. But I digress.) Presumably, an ALBM with its high speed (and likely a maneuvering warhead) would be far more capable against systems such as the S-300/400/500. Increasing the B-52's standoff range would also improve the survivability of it as a launch platform. (Wiki claims a range of up to 600 km / 370 miles for the S-500, although S-500 appears to be designed as an ABM, it is likely very capable against nonmaneuvering targets like a B-52).

 

The Russian missile is claimed to have a range of up to 3,000 km (1,800 miles) when launched from a supersonic platform such as the MiG-31 or Tu-22M. The B-52 is a slower platform, so a US missile would have to be larger or use some other tricks to get a similar range to the Kh-47. Alternatively, assuming a missile in the 10,000 lb weight class, an upgraded pylon could carry two of them. This would be highly beneficial, considering the low numbers of strategic bombers in the US fleet.

 

https://www.flightglobal.com/news/articles/lockheed-martin-claims-both-usaf-hypersonic-programm-450968/

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...And Boeing snatches another win, this time in the form of the T-X trainer competition:

 

http://boeing.mediaroom.com/2018-09-27-Boeing-Wins-U-S-Air-Force-T-X-Pilot-Training-Program-Contract

Quote
Boeing Wins U.S. Air Force T-X Pilot Training Program Contract
$9.2 billion award funds 351 jets, 46 simulators and associated ground equipment
ST. LOUIS, Sept. 27, 2018
– U.S. Air Force pilots will soon train for combat with T-X jets and simulators from Boeing [NYSE: BA].

“Today’s announcement is the culmination of years of unwavering focus by the Boeing and Saab team,” said Leanne Caret, president and CEO, Boeing Defense, Space & Security. “It is a direct result of our joint investment in developing a system centered on the unique requirements of the U.S. Air Force. We expect T-X to be a franchise program for much of this century.”

Boeing and its risk-sharing partner Saab designed, developed, and flight tested two all-new, purpose-built jets ― proving out the system’s design, repeatability in manufacturing and training capability.

“This selection allows our two companies to deliver on a commitment we jointly made nearly five years ago,” said Håkan Buskhe, president and CEO of Saab. “It is a major accomplishment for our partnership with Boeing and our joint team, and I look forward to delivering the first trainer aircraft to the Air Force.”

Boeing is now clear to begin placing orders with its suppliers, including Saab. More than 90 percent of Boeing’s offering will be made in America, supporting more than 17,000 jobs in 34 states.

Saab serves the global market with world-leading products, services and solutions within military defense and civil security. Saab has operations and employees on all continents around the world. Through innovative, collaborative and pragmatic thinking, Saab develops, adopts and improves new technology to meet customers’ changing needs.

For more information on Defense, Space & Security, visit www.boeing.com. Follow us on Twitter: @BoeingDefense and @BoeingSpace.

http://www.thedrive.com/the-war-zone/23889/boeing-wins-big-again-and-claims-the-usafs-huge-t-x-jet-trainer-deal

 

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Interesting.  I'm sure T-X sure has been an exciting ride, with a wide field of competitors and Northrop dropping out only a few months after they showed off their fancy new design.

 

I spoke to a fighter pilot who opined that it didn't really matter who won T-X so much as getting T-Xs ASAP to replace the old T-38s.

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https://bmpd.livejournal.com/3359540.html

Quote

   Interesting photos of an test bed MiG-31 fighter (81 blue), which performs test flights in Zhukovsky with a mass-size mock up of, presumably, a missile of an anti-space / anti-satellite missile system of a new type. It is reported that the test flights of the modified jet (possibly designated as "type 08") with this model of a missile are being carried out in Zhukovsky since February 2018.

5981497_original.jpg

 

Quote

 /.../

   ...back in the 1980s, the USSR was building an anti-space defense complex 30P6 "Contact" (the lead developer of the system was "Almaz") with an anti-satellite missile 79M6 (the developer of which was "Fakel") using as a carrier a specially modified MiG- 31D ("type 07"). As a means of target designation, the "Contact" complex was to use the radar-optical complex for recognition of cosmic objects of 45Zh6 "Krona" deployed at the Sary-Shagan. The "Contact" complex, according to known data, was not brought to the stage of full-fledged flight tests and after the collapse of the USSR the work was stopped, and two already built MiG-31D fighter carriers (on-board numbers "071" and "072") remained on the territory of Kazakhstan . It is also known that at the turn of the 1980s-1990s, the work on the creation of a modified rocket of this complex under the possible index 95M6 was conducted at the "Fakel".

 

   On August 11, 2009, the then commander-in-chief of the Russian Air Force Colonel-General Alexander Zelin stated that "during the Soviet era, an MiG-31 airplane was created for the tasks of the anti-space defense" and that "this system is being reanimated to solve the same tasks." In 2009-2010, there were also reports on the modernization of the complex recognition of space objects "Krona" at the Sary-Shagan range.

 

   The modified MiG-31 fighter with the onboard number "81 blue" has been observed in Zhukovsky since 2016, but only now it was captured with the mock up of rocket.

 

5981930_original.jpg

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https://www.janes.com/article/83773/aero-rolls-out-first-l-39ng

 

"First launched at the 2014 Farnborough International Airshow, the L-39NG version of the L-39 Albatross features a more powerful Williams International FJ44-4M engine, a wet wing, a modern cockpit, and a lighter airframe than its predecessor. It is equipped with five hardpoints (compared with two for the baseline L-39) for a variety of air-to-air and air-to-surface missiles (AAMs), as well as other munitions and sensors. It also introduces the option for a gun-pod."

 

p1728601_main.jpg

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SH Nobility member @OnlySlightlyCrazy did some excellent research, and asked an old missile design grognard why on earth the R-27 has those weird axe-head shaped fins.  I have copied the explanation below in full:

 

Quote
so R-27 was intended to have a longer F-Pole than AIM-7F, which means that you want wing link surfaces and high aspect ratios
however, the swapable nose cones means that you can't really do nose controls, so you need midbody - ergo big - fins
long narrow fins move your dynamic loading such that the center of pressure is closer to the control hinge, meaning better time constant and less battery juice sucked up.
 
now
 
aWfmPKX.png
 

that's an R-27

we can clearly see that the module in front of it is the autopilot and fuze, so it's space limited forward

and you want it to be as far forward as possible for aero reasons

ergo you make it widen at the outer edges, making an axe-shape

 

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I should probably clarify what is the grognard's opinions - and these are opinions, he hasn't seen any actual design documents on the R-27/AA-10 - and what are my own assumptions working off of what he posited. 

Grognard (almost verbatim):

 

The [R-27...] was designed as something that would counter the AIM-7F missile and would have better maneuverability and expanded F-Pole over the Sparrow.

 

The missile is much larger than Sparrow, particularly the longer range variants.

 

The stuff he's seen says that the AA-10 has Canard control. I guess you could take your choice whether its Canard or Mid-body wing control. In any event, the control fins are place closer to mid-body than to the nose.  These mid-body control finds need to be larger to generate maneuvers because the moment arm between the center-of-pressure and center-of-gravity is much smaller than for true canard or tail control. The sparrow also has large wings for this reason.

 

Given the large size of the control surfaces, he suspects that the designers were trying to provide “wing-like” surface for long range flight profiles that are quoted. The higher aspect surfaces are of higher aspect ratio, and that in turn provides an improved lift-to-drag ratio on lifting surfaces.

 

This is the only missile he can recall that has control surfaces extended out past the tail fins. The longer (and narrower) control surfaces would concentrate the dynamic loading such that the individual surfaces would have the center of pressure closer to the control hinge axis. This means the surfaces can be rotated with less torque than something like the AIM-7. As such, the control surface actuators would require less power to operate and would most likely respond faster while still maintaining sufficient force to affect the body rotation during maneuvering.   

 

He thinks the drawback of this design is that the wings would interfere with conventional launch rail systems, and would not fit into internal weapons bays. This may be why you don’t see a lot of this design; however, from an aerodynamic perspective, he thinks the long, narrower fins are more efficient both in reducing drag and in minimizing control torque requirement.

OnlySlightlyCrazy:

One of the leading factors in a missile's RMax is it's battery life - many missiles can aerodynamically hit targets much further than their battery can last out to. Thus, having more efficient control surfaces on a missile desiring long range makes sense.

As to why the fins are midbody - that's the swappable nosecone bit that Colli shared. That image also explains the forward angle on the midbody fins; you want your fins to be as large as possible since they're midbody, and you want them as far forward as you can get them without intruding into the autopilot or Target Detection Device sections. Thus, having it swept forward means you get a wider fin farther forward, and get to not intrude into other necessary components. That forward sweep is frankly the only usual part of the fin - combining a forward sweep with a conventional fin geometry is what gets you the axe-body. 

I'm happy to take a crack at further questions myself, or forward them to said grognard before he retires and or dies. 

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I wonder how big the cab le is between the seeker and autopilot? Obvious solution is to stack the missile seeker-fins-autopilot to get the fins closer to the nose, so there must be a good reason they didn't just do that

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My naive response to that is that the Target Detection Device needs to be as far forward as is practical in order to keep your warhead on target when it fuzes and detonates. (At 25kft a Mach 2 missile will pass the entire length of an F-4 Phantom in .06 seconds, which is before you address the fact that the target is moving and you need time for your continuous rod to get on target.) This is a shared configuration with the AIM-7, also a continuous rod warhead missile. Given that the R-27 is a 1980s era missile, it's also possible that the autopilot is electromechanical, not digital, and therefore cannot be trivially removed from the seeker via cable. All this is, of course, speculation.

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