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91
Missile Projects / Re: F-86 proposed as cruise missile
« Last post by XP67_Moonbat on Yesterday at 12:54:57 pm »
Scott, do you have the pic of that B-45 drone? The picture's link in your APR article is dead.
92
The Bar / Re: Rearming the UK: What equipment? and how much?
« Last post by Triton on Yesterday at 12:43:47 pm »
"Britain's new aircraft carriers to test Beijing in South China Sea "
by Ben Doherty

July 27, 2017

Source:
https://www.theguardian.com/uk-news/2017/jul/27/britains-new-aircraft-carriers-to-test-beijing-in-south-china-sea


93
Military / Re: US Prompt Global Strike Capability
« Last post by Flyaway on Yesterday at 12:42:52 pm »
Orbital ATK Receives $21 Million Hypersonic Propulsion Contract from DARPA

http://www.parabolicarc.com/2017/09/19/orbital-atk-darpa-contract/

That engine looks not dissimilar to the engine Aerojet Rocketdyne are developing for the so called LM SR-72.

http://www.popularmechanics.com/military/aviation/a26796/hypersonic-sr-72-aircraft/
94
The Bar / Re: Rearming the UK: What equipment? and how much?
« Last post by uk 75 on Yesterday at 12:19:01 pm »
JFC
Always interesting to read your info.
The combination of QE, Albion, the remaining
Bay class plus in extremis Bulwark and
P of W working closely sometimes with
the US Marines is quite a decent force.
Despite their age T23 with Merlin or Wildcat
compare well with most NATO escort
ships.
The T45 is a capability which US commanders
visibly like having in a Task Group.
T and A nuke sub's are a unique asset.
Its just a shame the Navy is not as good
as it should be on PR. Bring back WARShip!
95
Aerospace / Re: Northrop Grumman B-21 Long Range Strike Bomber
« Last post by Flyaway on Yesterday at 12:14:06 pm »
Quote
AFA: In what may be a hint of things to come, the head of the Air Force Rapid Capabilities Office says his office is keeping a close eye on the B-21 bomber’s stealth costs. While he didn’t indicate there were any cost overruns or scheduler problems, the fact that RCO Director Randall Walden mentioned this for the first time in public would seem to indicate a heightened level of interest.

Quote
If we put a few pieces together, Walden may be focused on stealth because Northrop Grumman, the plane’s builder, is constructing a new 45,900 square foot “coatings facility” at its facility at Air Force Plant 42 in Palmdale, Calif. And, as Walden noted during a panel yesterday, stealth is one of the program’s most likely risk areas.

I confirmed that the plant is part of the B-21 program and that the facility would be key to stealth coatings for the plane. Development of a stand-alone plant for coatings, presumably for stealth, highlights the importance of security to the program.

Bottom line on the B-21 program seems to be summed up by Walden’s comment that, “Based on what I’ve seen so far, it’s actually a pretty good deal for us and the taxpayers.”

http://breakingdefense.com/2017/09/rapid-capabilities-office-watching-b-21-stealth-costs-closely/
96
Aerospace / Re: Lockheed Martin F-35: News ONLY topic
« Last post by Flyaway on Yesterday at 12:05:47 pm »
UK outlines IOC target for F-35s

Quote
The UK remains on target to achieve initial operational capability (IOC) with the Lockheed Martin F-35B in late 2018, with its personnel training and testing activities gathering pace.

https://www.flightglobal.com/news/articles/uk-outlines-ioc-target-for-f-35s-441280/
98
Military / Re: Nuclear Weapons NEWS ONLY
« Last post by Flyaway on Yesterday at 12:03:45 pm »
New ICBM gets boost after Mattis’ endorsement

Quote
NATIONAL HARBOR, Md. — The unexpected escalation of North Korea’s atomic weapons program and Russia’s nuclear posturing are providing fresh momentum to U.S. efforts to develop a new intercontinental ballistic missile.

Early doubts about the future of the next-generation ICBM, known as the ground-based strategic deterrent (GBSD), are giving way to a growing confidence that the Pentagon is fully behind the program, military officials said Sept. 18 at the Air Force Association’s Air Space Cyber conference.

Defense Secretary Jim Mattis in the past had raised questions about the need to develop a new ICBM to replace the 50-year-old Minuteman, but now firmly supports it. “Secretary Mattis said he did not see a future triad without the ICBM,” asserted Maj. Gen. Anthony Cotton, commander of the 20th Air Force at Global Strike Command. Mattis gave the GBSD a ringing endorsement last week during a visit to Minot Air Force Base, North Dakota, the only U.S. base to host two legs of the nuclear triad — strategic bombers and ICBMs.

http://spacenews.com/new-icbm-gets-boost-after-mattis-endorsement/
99
Aerospace / Re: KFX Korean Indigenous Fighter programme
« Last post by DWG on Yesterday at 11:41:30 am »
It's just plain mathematical equations for each output, with associated logic to tell you what to do in which part of the flight envelope, often with associated filtering and smoothing for either input or output. With Weight on Wheels that ended up being about a dozen lines of logic to combine half a dozen inputs just to decide if we were actually on the ground or not. (That's technically the Mode Logic part of Dixon's central model, but IMO you can't usefully separate it from what he labels Control Laws or Gains because the operations on any individual data item are a combination of all three.) Similarly for every other piece of data we're processing.

I'm puzzled by your assertion that matrices are adapted to programming languages, combined with the apparent assertion that therefore doesn't require implementation. I'm an Ada specialist, but I've worked in most of the engineering languages at one time or another. Most have data structures that will handle matrices,to some extent or other, but you still have to define that data structure in code, still have to get the data into it, with associated filtering and smoothing, and then you have to code every mathematical operation that happens to that data (and if you're using a sensible language, ensure that every variable the data passes through is dimensionally and range consistent - remember Mars Climate Orbiter). And it's been a while, but I really don't remember any significant use of matrices, mostly just individual variables for stuff like ComputedAirspeed or PitchAngle or WeightOnLeftMainGear. I suspect you're being confused by the differences between a Matlab model, a requirements document, and actual operational flight code.
100
Aerospace / Re: NPL Research Biplane Design
« Last post by robunos on Yesterday at 11:29:48 am »
A-HA!!
This was the work of N.P. Irving, an aerodynamicist at the NPL. The configuration was designed to give good behaviour at low speeds and near the stall.
In 1935, this configuration was used by Airspeed for one version of the AS.27, a slow-speed coastal patrol and general purpose aircraft.
The below from Putnam's 'Airspeed', page 152 :-

"AS.27
The designation AS.27 was orginally given to a project intended to meet a
requirement for a slow-speed coastal patrol and general purpose aircraft.
Designed in 1935, this was a highly unconventional single-engined biplane
with its wing arrangement following principles developed by H. B. Irving,
the National Physical Laboratory aerodynamicist, intended to give the
aircraft a wide speed range and good slow-speed stability.
At about this time there was also a requirement for a ‘special defence’
aircraft which,flying in or above cloud, would trail a winched-out cable or cables,
possibly carrying high explosive, to menace enemy bombers. The idea was
that these aircraft would be flown by second-line pilots, although at that
time no plans had been made to recruit and train such pilots. The largely
abortive Civil Air Guard had yet to be formed, and the far from abortive
Air Transport Auxiliary was not formed until war was imminent in 1939.
Another, very different, version of the AS.27 was therefore designed
late in 1936. This, a characteristically handsome single-engined high-
wing cabin monoplane, was considered likely to be more suited to the
‘special defence’ role, though design and development work on the Irving-
wing biplane continued. Orders were placed by the Air Ministry for two
prototypes of the AS.27, and RAF serial numbers K8846-8847 were
allocated, but neither aircraft was built.
The Irving-wing AS.27, to be powered by a 225 hp Wolseley Aries, or
250 hp Wolseley Scorpio, both nine-cylinder radials, was a heavily
staggered biplane, with the upper wing sharply tapered and with the
lower wing, of more conventional planform, having a marked dihedral
and forward sweep. A wide split-axle undercarriage with long-movement
oleos was fitted. The cockpit was enclosed and the pilot would have had
a good view forward and downward ahead of the lower wing. The estimated
speed range of this version of the AS.27 was 43-121 mph.
The monoplane special defence project was to have been powered
by a 350 hp Armstrong Siddeley Cheetah IX seven-cylinder radial, in a
helmeted cowling. It was a clean high-wing cabin monoplane with single-
strut bracing and cantilever undercarriage legs with internally sprung
wheels. The engine was low-slung so that the single centrally-seated pilot
would have had a good range of forward and downward view. The wing
was tapered, with slots ahead of the ailerons and plain flaps inboard. The
tailplane was a cantilever structure."

Image source also Putnam's 'Airspeed', page 153. Apologies for the quality, the original has very fine lines, which don't scan well.


cheers,
          Robin.




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