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Aerospace / Re: reason for mirage 2000 slat angle
« Last post by TomcatViP on Today at 01:37:47 pm »
The ratio b/w wing chord and slat length is variable with the position on the wing. Because delta have large chord and low thickness, the percentage of lenght in the slat that is deflected vary greatly.
Now, slat angle increases curvature that increases local AoA
 A 10% slotted section, won't reach same AoA than one at a 20% ratio. Hence the duscretisation of the wing LE.

The F4 has the same arrangement.
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Aerospace / Re: Bigelow Aerospace Space Stations
« Last post by Flyaway on Today at 01:19:55 pm »
Here’s an article including the cost.

Quote
Now Bigelow Aerospace proposes sending a much larger version, known as the B330, into orbit around the moon. If NASA goes for it, the $2.3 billion mission would go something like this:

https://www.washingtonpost.com/news/the-switch/wp/2017/10/17/heres-how-a-las-vegas-millionaire-plans-to-build-an-orbiting-space-station-for-the-moon/?utm_term=.2640ddab33a6
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Aerospace / Re: reason for mirage 2000 slat angle
« Last post by Machdiamond on Today at 12:49:01 pm »
Highly swept wing or delta wing tend to stall outboard first and this induces a pitch up at stall, making things worse.

So here the outboard wing section can reach a higher AoA than the inboard section, so the inboard stalls first and pitches the aircraft down.

The generally preferred method is to leave a section of the wing leading edge near the wing root without slat, so you need only one slat per side and the stall starts at the root.
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Aerospace / Re: Bigelow Aerospace Space Stations
« Last post by Flyaway on Today at 12:28:59 pm »
Bigelow Aerospace and United Launch Alliance Announce Agreement to Place a B330 Habitat in Low Lunar Orbit

Las Vegas, NV and Centennial, Colo. (Oct. 17, 2017) – Bigelow Aerospace and United Launch Alliance (ULA) are working together to launch a B330 expandable module on ULA’s Vulcan launch vehicle.  The launch would place a B330 outfitted module in Low Lunar Orbit by the end of 2022 to serve as a lunar depot.

“We are excited to work with ULA on this lunar depot project,” said Robert Bigelow, president of Bigelow Aerospace. “Our lunar depot plan is a strong complement to other plans intended to eventually put people on Mars. It will provide NASA and America with an exciting and financially practical success opportunity that can be accomplished in the short term. This lunar depot could be deployed easily by 2022 to support the nation’s re-energized plans for returning to the Moon.

"This commercial lunar depot would provide anchorage for significant lunar business development in addition to offering NASA and other governments the Moon as a new exciting location to conduct long-term exploration and astronaut training.”

The B330 would launch to Low Earth Orbit on a Vulcan 562 configuration rocket, the only commercial launch vehicle in development today with sufficient performance and a large enough payload fairing to carry the habitat. Once the B330 is in orbit, Bigelow Aerospace will outfit the habitat and demonstrate it is working properly.  Once the B330 is fully operational, ULA’s industry-unique distributed lift capability would be used to send the B330 to lunar orbit.  Distributed lift would also utilize two more Vulcan ACES launches, each carrying 35 tons of cryogenic propellant to low Earth orbit.  In LEO, all of the cryogenic propellant would be transferred to one of the Advanced Cryogenic Evolved Stage (ACES). The now full ACES would then rendezvous with the B330 and perform multiple maneuvers to deliver the B330 to its final position in Low Lunar Orbit.

“We are so pleased to be able to continue our relationship with Bigelow Aerospace,” said Tory Bruno, ULA’s president and CEO. “The company is doing such tremendous work in the area of habitats for visiting, living and working off our planet and we are thrilled to be the ride that enables that reality.” 

Bigelow Aerospace is a destination-oriented company with a focus on expandable systems for use in a variety of space applications.  These NASA heritage systems provide for greater volume, safety, opportunity and economy than the aluminum alternatives.

The B330 is a standalone commercial space station that can operate in low Earth orbit, cislunar space and beyond.  A single B330 is comparable to one third of the current pressurized volume of the entire International Space Station.  Bigelow Aerospace is developing two B330 commercial space station habitats that will be ready for launch any time after 2020.

For more information on Bigelow Aerospace visit www.bigelowaerospace.com.  Connect with Bigelow Aerospace at www.facebook.com/bigelowaerospace, www.twitter.com/BigelowSpace and www.instagram.com/bigelowspace.

With more than a century of combined heritage, United Launch Alliance is the nation’s most experienced and reliable launch service provider. ULA has successfully delivered 120 satellites to orbit that provide critical capabilities for troops in the field, aid meteorologists in tracking severe weather, enable personal device-based GPS navigation and unlock the mysteries of our solar system.

For more information on ULA, visit the ULA website at www.ulalaunch.com, or call the ULA Launch Hotline at 1-877-ULA-4321 (852-4321). Join the conversation at www.facebook.com/ulalaunch, twitter.com/ulalaunch and instagram.com/ulalaunch.
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Quote
WASHINGTON — A Soyuz spacecraft returning three people to Earth in April experienced a partial loss of pressure during the final stages of its descent, but did not put the crew’s lives in danger.

The incident, revealed during an Oct. 16 meeting of NASA’s International Space Station Advisory Committee, is one of a series of events that have raised questions about the reliability of Russian vehicles supporting the station.

During the committee meeting, chairman Thomas Stafford, a former astronaut, said the incident took place when the main parachute of the Soyuz spacecraft deployed about eight kilometers above the landing site in Kazakhstan. A buckle that is part of the parachute system struck the capsule.

“The buckle struck a welding seam and, as a result, there was a depressurizing event that resulted in some air escaping the capsule,” he said.

Stafford didn’t identify the specific mission where this took place, other than to say that it happened in April of this year. The only Soyuz spacecraft to return to Earth that month was Soyuz MS-02, which landed April 10. It carried NASA astronaut Shane Kimbrough and Roscosmos cosmonauts Sergey Ryzhikov and Andrey Borisenko, who spent nearly six months on the ISS.

NASA spokesman Gary Jordan confirmed Oct. 17 that the incident took place during the Soyuz MS-02 landing. He referred additional questions about it to the Russian state space corporation Roscosmos, which has not publicly discussed it to date.

http://spacenews.com/soyuz-capsule-suffered-partial-depressurization-during-april-landing/
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Aerospace / Re: SpaceX (general discussion)
« Last post by Flyaway on Today at 12:01:15 pm »
7
Aerospace / Re: Boeing accuses Bombardier of "dumpng" CSeries jets . . .
« Last post by Triton on Today at 11:09:59 am »
"Boeing outmaneuvered? Airbus takes Bombardier under its wing"
By Aaron Gregg / The Washington Post

Tuesday, October 17, 2017

Source:
https://www.heraldnet.com/business/bombardier-to-partner-with-airbus-on-c-series-program/

Quote
...In its published reactions to Airbus and Bombardier’s combination, Boeing sought to cast the deal as a blatant attempt to circumvent U.S. trade law.

“This looks like a questionable deal between two heavily state-subsidized competitors to skirt the recent findings of the U.S. government,” a Boeing spokesman said in a statement Monday. “Our position remains that everyone should play by the same rules for free and fair trade to work.”

In a Monday evening call with reporters, executives from Airbus and Bombardier insisted the deal was motivated by a strategic business considerations and not a desire to avoid the tariff. Still, they recognized the added benefit of potentially avoiding the import duty.

“It’s not intended to circumvent anything, but the fact is that when you produce an aircraft in the U.S. it’s not subject to any U.S. import tariff rules,” Bombardier President Alain Bellemare said.

Trade experts question whether using an Alabama production facility would necessarily allow Airbus to waive the tariffs on the C Series plane. Much of the work of producing the plane comes down to assembly, with the actual components stretched across a global supply chain.
“There is a legal question of how much of the parts and components and value-added needs to actually happen in the U.S. for tariffs to no longer apply,” said Chad Bown, a senior fellow with the Peterson Institute for International Economics. “You can’t just fly an airplane to Alabama and say it’s made in America.”

But the combination could also give Bombardier new political clout in the United States, possibly making the import tax politically difficult for the White House. Airbus already operates a 53-acre facility in Mobile where it has produced the A320 narrow-body commercial jetliner since 2015 – the company’s first U.S. production facility.

As part of the announcement Monday Airbus said it will set up a second production center in Mobile, a move that could shift some of the plane’s future job creation potential from Quebec to the United States.

That could give the C Series another ally in Congress, where the tariff already faces resistance. In an October letter to the International Trade Commission a bipartisan group of four U.S. senators and three House members said they oppose the border tax.

“This destroys the trade complaint and guarantees the success of the C Series aircraft in the U.S.,” said Richard Aboulafia, an aerospace analyst with Teal Group.

Others said it is unlikely that Bombardier chose to embark on a combination purely because of the Commerce Department’s tariff decision.

“When a partner in a venture pays nothing to get on board it means you were in trouble to begin with,” said Loren Thompson, an aerospace consultant whose think-tank gets some funding from Boeing.
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Aerospace / Re: reason for mirage 2000 slat angle
« Last post by ScrutorAudax on Today at 08:32:54 am »
I know this is a bit late, but I suspect it is due to the local angle of attack.  The differential spanwise slat actuation itself doesn't appear to be for vortex control, as the difference in deflection is very small and there are no visible vortices that would be affected by this method of slat control.  It seems more likely that this is a product of the flow conditions (large vortical flow at the wings resulting in downwash at the root of the wing and upwash at the tip) of the delta wing planform.

This is what I can infer from the picture you provided; I hope it helps.
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Aerospace / Re: IAI Lavi
« Last post by Motocar on Today at 07:53:55 am »
Cutaway IAI Lavi retouched by Motocar
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