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1
Space Projects / Re: Stratolaunch
« Last post by sferrin on Today at 12:24:17 pm »
Hang a GRM-29A from that sucker:


2
Military / Re: Defense against Hypersonic Glide Vehicles
« Last post by sferrin on Today at 12:19:52 pm »
Even radar has problems getting through the plasma layer.  With Sprint they needed quite a bit of power to communicate through it.  I would think it would be even more difficult for a much shorter wavelength laser.
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Military / Re: Defense against Hypersonic Glide Vehicles
« Last post by sublight is back on Today at 12:12:59 pm »
.....seem to have quite enough problems dealing with normal atmospheric distortion and turbulence.

Only if they are coming from the terrestrial side....  ;)
4
Space Projects / Re: Stratolaunch
« Last post by martinbayer on Today at 12:10:09 pm »
Quote
delta winged orbiters with cryogenic rocket propulsion

Delta wing = heavy

Cryogenic propulsion: ISP red herring, cryogens makes tanks giant PITA.

Rather than speaking in generalities, I recommend to read the papers and discuss the specific designs and how those aspects were addressed.
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Space Projects / Re: Stratolaunch
« Last post by Archibald on Today at 12:06:13 pm »
Quote
delta winged orbiters with cryogenic rocket propulsion

Delta wing = heavy

Cryogenic propulsion: ISP red herring, cryogens makes tanks giant PITA.

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Military / Re: Defense against Hypersonic Glide Vehicles
« Last post by Trident on Today at 11:44:16 am »
Said structures are operating in a thermal environment which is already challenging to begin with though, so there might not be a lot of margin to bear additional heat load. The straw which breaks the camel's back...

I do agree about the optical challenges imposed by hypersonic flow past the target - lasers currently seem to have quite enough problems dealing with normal atmospheric distortion and turbulence.
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Space Projects / Re: Stratolaunch
« Last post by martinbayer on Today at 11:36:55 am »
Once again, it comes down to the specific numbers of an actual design, i.e. whether the difference between the required 90% PMF and the ET like 96% PMF allows to integrate all required additional systems, modifications and load conditions plus a meaningful orbital payload.  for two examples of concept studies for reusable delta winged orbiters with cryogenic rocket propulsion and subsonic air launch separation at Mach 0.8 and about 9 - 10 kilometers altitude. .

 Neither of them are going to approach even 90% PMF

Both designs had an orbiter air launch mass of 250 metric tons, which exactly (and perhaps not coincidentally) corresponds to the Stratolaunch 'Roc' payload lift capacity, and both studies arrived at a corresponding orbital payload capability of around 7 metric tons to LEO.

yes, coincidental

True - the analyses yielded total PMFs (including residuals and RCS/OMS propellants) of 0.855 and 0.843, respectively, which, for the chosen/optimized propulsion systems, launch conditions, ascent trajectories, and target orbits, were in both cases found to be sufficient to achieve the stated payload performance.

Since you confidently assert that the Roc payload determination was coincidental to the sizing assumptions of both studies, did you take part in the Stratolaunch requirements definition process?
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Vice versa... The Aerovan concept was the inspirationsource for the M.61 & M.62 freighters
according to 'Miles Aircraft'
覧覧覧覧覧覧覧覧覧

Which contributed to the still-born Hurel-Dubois-Miles 106 Caravan concept.
After that concept was transferred to Short Brothers, it eventually reached production as the Shorts Skyvan, my favourite skydiving platform!
9
Hi all! First post on the Forum)

Some words about Grokhovsky G-38.

It seems to me, that well known plans, images and 3d model that were posted by Redstar72 and blackkite are fake based on pic from the TM (Техника Молодежи) magazine 08 sep 1938.http://zhurnalko.net/=nauka-i-tehnika/tehnika-molodezhi/1938-08-09

But in fact this pic described as

Quote
Двух балочныйサ самолет, который демонстрировался на Парижской выставке. Хвостовое оперение приближено к крылу. Этот самолет переходная ступень к бесхвостым ォлетающим крыльямサ
or in Eng:
Quote
Two tail plane demonstrated on Paris air show [in 1936]. Aircraft tail moved closely to wing. This plane is intermediate stage to tailless "flying wings".

So this pic is just an "author`s vision" of Fokker`s G-1 performed by A. Preobrazhensky or S. Lodygin for article.

What a Fate`s joke: real Ivensen-Grokhovsky project replaced by fake, based on picture for (again) Grokhovsky`s article.

But in article about P.A. Ivensen i found another image of G-38 
http://sm.evg-rumjantsev.ru/des2/ivensen.html

And later - side view of G-38 in book Aircraft industry of USSR 1917-1945 part I (Самолетостроение в СССР 1917-1941 том 1) ch.5 p.245.

10
Is the canard pivoted around a vertical hinge axis?
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