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Naval Projects / Re: NSSN Virginia-class - current status and future
« Last post by bobbymike on Today at 11:56:02 am »

The Navy’s next class fast attack submarine will be designed for a return to blue-water great power competition, where the ability to support forces ashore is less important than operating in the open ocean hunting rival submarines, according to an analysis of the Navy’s 30 Year shipbuilding plan conducted by Congressional Budget Office (CBO).

The Navy plans to start purchasing this new class of submarine in 2034. Previously the SSN(X) class were assumed to be a successor to the current Virginia-class submarine, complete with the Virginia Payload Module (VPM) – a vertical launch system that increases the number of Tomahawk-sized weapons from 12 to 40 – and other acoustic and technological design improvements, according to the CBO analysis released Thursday.
Early Aircraft Projects / Re: Projects in Switzerland
« Last post by Kuno on Today at 11:15:30 am »
...I am focusing on the SB-2 at present. The target is to have its full story published in a little book in the first half of 2019... still a far way to go...
Early Aircraft Projects / Re: Blohm und Voss P.185
« Last post by Kuno on Today at 11:10:20 am »
Good arguments!
Turns out, one of the TB's intended engines has survived:
:o Lockheed should definitely stick to designing aircraft.  Even for the era, those are some of the worst FA uniforms I've ever seen...
So, no appreciation for Pucci, then?  I'd rather see this than the outfits I saw on a Virgin America flight from a few years ago.  At that time, I was wondering who these people in '80s workout clothes were helping people with their carry on bags.

I enjoyed seeing these again, particularly the close up shot on the Lockheed SST.
Postwar Aircraft Projects / Re: Fairchild M-185F
« Last post by famvburg on Today at 07:47:31 am »
IIRC, they were B-47 engines, pylons and nacelles.
Early Aircraft Projects / Re: Projects in Switzerland
« Last post by hesham on Today at 05:38:03 am »
Very nice Info dear Kuno,

and we are thirsty for more Projects.
Space Projects / Re: Manned "Cloudbase" in Venus Atmosphere
« Last post by Archibald on Today at 05:00:15 am »
Now that's interesting. Well I suppose the main drawback is Venus gravity pull, which is as bad as Earth, since they are the same size and mass. The huge issue would be to get the processed phosphorus out of Venus gravity well.  It is a giant PITA on Earth for any SSTO, and it must be the exact, same giant PITA on Venus.

Going from a Venus floating cloudbase station to Venus orbit or escape is very similar to air-launching a planetary probe on Earth. Balloons or aircraft substract less than 1 km/s of delta-v, but escaping from the planet takes 11 km/s, plus that's logarithm, not decimal, so far worse than "11 times", closer from 15 or 20 times the energy.

It essentially boils down to
7.7 km/s from Earth surface to Earth orbit, minus drag and gravity losses (balloons change nothing compared to surface), so +1.5 km/s, total 9.2 km/s. Then that's Earth orbit, Earth escape is 11.2 km/s, so that's +2 km/s.
Venus has the exact same issue - the delta-v must be extremely similar since, while Venus is a little smaller than Earth, its atmosphere is thick chicken soup so drag losses must be worse than Earth.

As much as I like HAVOC sheer coolness factor, the huge issue would be for the crew capsule to lift-off from the zeppelin and to accelerate to Venus escape velocity - 11 km/s or bust ! A manned capsule is one hell of a heavy thing (20 000 to 50 000 pounds) and the rocket to launch it to 11 km/s is pretty huge, and the whole thing hangs on a Zeppelin ? Really ?
Admittedly, airships have far more lift on Venus than Earth because the atmosphere is extremely dense. But if one compare with Stratolaunch, then you need some kind of "Stratolaunch Zeppelin" to launch a 250 mt ton rocket, Delta II size, with a 12 000 pound capsule (and 12 000 pounds is a Soyuz-size capsule, very very small). And then, not even sure it can even reach Venus orbit, minus escape velocity.
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