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Af/Pak & Other News (2/7/2012)

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dump...@hotmail.com

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Feb 7, 2012, 12:24:38 PM2/7/12
to
McRaven: US special ops in Afghanistan combine to prepare for greater
role as troops draw down:

http://www.washingtonpost.com/politics/mcraven-us-special-ops-in-afghanistan-combine-to-prepare-for-greater-role-as-troops-draw-down/2012/02/07/gIQAvkZKwQ_story.html



Pakistan gets new fighter planes from US:

http://timesofindia.indiatimes.com/world/pakistan/Pakistan-gets-new-fighter-planes-from-US/articleshow/11790180.cms




First Afghan pilot class completes flight screening course:

http://www.af.mil/news/story.asp?id=123288770



India Eyes More Drones For IAF:

http://www.aviationweek.com/aw/generic/story.jsp?id=news/asd/2012/02/06/02.xml&headline=IndiaEyesMoreDronesForIAF&channel=defense



Camera phones pose security threat to aircraft carrier project:

http://articles.timesofindia.indiatimes.com/2012-02-06/kochi/31031109_1_mobile-phones-aircraft-carrier-cochin-shipyard-limited



Boeing confirms Indian order for 10 C-17s as Indian defence market
grows:

http://www.defenceweb.co.za/index.php?option=com_content&view=article&id=23282:boeing-confirms-indian-order-for-10-c-17s-as-indian-defence-market-grows&catid=35:Aerospace&Itemid=107




UK and France Desperate to be Included in Mid East Ops?:

http://defensetech.org/2012/02/07/uk-and-france-desperate-to-be-included-in-mid-east-ops/



Russia's Lavrov seeks peace in Syria as forces bombard Homs:

http://af.reuters.com/article/commoditiesNews/idAFL5E8D73EK20120207



'Israel to ask for military facility in Cyprus':

http://www.jpost.com/Defense/Article.aspx?id=256844




Turkey willing to develop T-129 with South Korea:

http://alert5.com/2012/02/07/turkey-willing-to-develop-t-129-with-south-korea/



IAI and Boeing drive to active Arrow-3:

http://www.spacedaily.com/reports/IAI_and_Boeing_drive_to_active_Arrow-3_999.html




Russia to Deploy 7 Subs in Black Sea by 2017:

http://www.defencetalk.com/russia-to-deploy-7-subs-in-black-sea-by-2017-40323/



Trouble in paradise: Maldives president quits after cops mutiny:

http://worldnews.msnbc.msn.com/_news/2012/02/07/10337283-trouble-in-paradise-maldives-president-quits-after-cops-mutiny



Red Cross: 29 Chinese held in Sudan were released:

http://www.google.com/hostednews/ap/article/ALeqM5hNqwPLcM2wTQYZ86l2nz5ZViIf_w?docId=a303f6c3dc554af7822c21d65c8dcfb2



Did Chinese Espionage Lead to F-35 Delays?:

http://defensetech.org/2012/02/06/did-chinese-espionage-lead-to-f-35-delays/



Ohio man admits fundraising help for Somalia terror group al-Shabab:

http://www.msnbc.msn.com/id/46291809/ns/us_news-crime_and_courts/




Delivery of S-500 Air Defense System Delayed Until 2017:

http://www.defencetalk.com/delivery-of-s-500-air-defense-system-delayed-until-2017-40339/



Drills prepare Enterprise for final deployment:

http://www.navytimes.com/news/2012/02/navy-drills-prepare-enterprise-final-deployment-020512w/



Elbit unveils camouflage detector:

http://www.jpost.com/Defense/Article.aspx?id=256762



The Army Wants You … to Be a Virtual Lab Rat:

http://www.wired.com/dangerroom/2012/02/army-lab-rats/



Navy Equips Unmanned Boats with Non-Lethal Weapons:

http://www.defencetalk.com/navy-equips-unmanned-boats-with-non-lethal-weapons-40329/



US Navy testing railgun prototype:

http://www.defenceweb.co.za/index.php?option=com_content&view=article&id=23269:us-navy-testing-railgun-prototype&catid=90:science-a-technology&Itemid=204



Hackers sought $50,000 from Symantec for anti-virus blueprint:

http://www.reuters.com/article/2012/02/07/us-symantec-hackers-idUSTRE8160KB20120207



Andrew Swallow

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Feb 7, 2012, 3:19:21 PM2/7/12
to
A possible 220 nm - I hope they have some sort of guidance system in the
shell. Even at 50 nautical miles they are over the horizon.

Andrew Swallow

dump...@hotmail.com

unread,
Feb 7, 2012, 5:05:22 PM2/7/12
to
On Feb 7, 12:19 pm, Andrew Swallow <am.swal...@btinternet.com> wrote:
> On 07/02/2012 17:24, dumpst...@hotmail.com wrote:
>
> > US Navy testing railgun prototype:
>
> >http://www.defenceweb.co.za/index.php?option=com_content&view=article...
>
> A possible 220 nm - I hope they have some sort of guidance system in the
> shell.  Even at 50 nautical miles they are over the horizon.
>
> Andrew Swallow


That's nuthin'. Check out this badboy:

http://www.popsci.com/technology/article/2010-01/cannon-shooting-supplies-space

Imagine an arty version with GPS-guided shells.

Dan

unread,
Feb 7, 2012, 6:58:40 PM2/7/12
to
Gerald Bull would be impressed.

Dan, U.S. Air Force, retired

dump...@hotmail.com

unread,
Feb 8, 2012, 12:31:47 AM2/8/12
to
On Feb 7, 3:58 pm, Dan <B24...@aol.com> wrote:
> On 2/7/2012 4:05 PM, dumpst...@hotmail.com wrote:
>
>
>
>
>
>
>
>
>
> > On Feb 7, 12:19 pm, Andrew Swallow<am.swal...@btinternet.com>  wrote:
> >> On 07/02/2012 17:24, dumpst...@hotmail.com wrote:
>
> >>> US Navy testing railgun prototype:
>
> >>>http://www.defenceweb.co.za/index.php?option=com_content&view=article...
>
> >> A possible 220 nm - I hope they have some sort of guidance system in the
> >> shell.  Even at 50 nautical miles they are over the horizon.
>
> >> Andrew Swallow
>
> > That's nuthin'.  Check out this badboy:
>
> >http://www.popsci.com/technology/article/2010-01/cannon-shooting-supp...
>
> > Imagine an arty version with GPS-guided shells.
>
>    Gerald Bull would be impressed.
>
> Dan, U.S. Air Force, retired

I wonder if developments like these will usher in a new era of big
naval guns
(without the Battleships this time)?

Dean Markley

unread,
Feb 8, 2012, 8:48:10 AM2/8/12
to
I guarantee you that the very first ship outfitted with one of these
will be called a battleship by some member of the media.

dott.Piergiorgio

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Feb 8, 2012, 11:21:10 AM2/8/12
to
Il 08/02/2012 06:31, dump...@hotmail.com ha scritto:

> I wonder if developments like these will usher in a new era of big
> naval guns
> (without the Battleships this time)?

I fully agree; but the inevitable race to larger calibres will lead to
the fearful "bringing back the B*, this time with full honours and back
to their rightful throne"

there's interesting times ahead for s.m.n. ....

Best regards from Italy,
dott. Piergiorgio.

dott.Piergiorgio

unread,
Feb 8, 2012, 11:37:57 AM2/8/12
to
Il 08/02/2012 14:48, Dean Markley ha scritto:

>> I wonder if developments like these will usher in a new era of big
>> naval guns
>> (without the Battleships this time)?
>
> I guarantee you that the very first ship outfitted with one of these
> will be called a battleship by some member of the media.

not only from the media....

there's definite advantages in returning to the good old ways; first and
foremost, is much more easy explain to politicos and public opinion the
procurement and comparing it to that of foreign countries in simple and
unclassified physical & numerical terms; diplomats, wizened by the prior
mistakes at Washington and London have much more quantifiable yardsticks
in talks, public opinion get more understanding in their Navies and
reality of their needs and capabilities, and last but not least, is easy
to point to the bore diameter to the visiting press aboard and
explaining without possibilities of misunderstandment what they ought to
write in their articles ;)

bill

unread,
Feb 8, 2012, 1:40:22 PM2/8/12
to
On Tue, 07 Feb 2012 17:58:40 -0600, Dan wrote:


>> Imagine an arty version with GPS-guided shells.
>
> Gerald Bull would be impressed.
>

I imagine it has already impressed the people who did something very
nasty to the late Dr Bull.

One must assume that Mr Hunter has made sure exactly who his backers
are...

--
"Hopefully the fair wind will resume, or this may well take all day."

Admiral Collingwood on being becalmed under the guns of six French ships-
of-the-line at Trafalgar

Shawn Wilson

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Feb 8, 2012, 3:43:56 PM2/8/12
to
On Feb 7, 1:19 pm, Andrew Swallow <am.swal...@btinternet.com> wrote:
> On 07/02/2012 17:24, dumpst...@hotmail.com wrote:
>
> > US Navy testing railgun prototype:
>
> >http://www.defenceweb.co.za/index.php?option=com_content&view=article.
>
> A possible 220 nm - I hope they have some sort of guidance system in the
> shell.  Even at 50 nautical miles they are over the horizon.


"The first industry-built launcher, a 32-megajoule prototype
demonstrator made by BAE Systems, arrived at Naval Surface Warfare
Centre (NSWC) Dahlgren, Virginia, on January 30."

32 Megajoules? That's IT??? A BATTLESHIP main gun (specifically the
Iowa's) produces 290+ megajoules*. 32 is little more than a tank
cannon produces. (well, about 3/2 x)

*the formula being 1/2 x mass (kilos) x velocity^2 (meters/second).


Approximate muzzle energies-

Iowa- 290 million (per gun)

Abrahms- 20 million

9mm or .45 pistol- 500 (no, not million... just 500)

.357 or 10mm pistol- 700

M-16A2 or AK-47- 1800

M-1 rifle- 3000

.50 BMG- 18,000




Andrew Swallow

unread,
Feb 8, 2012, 4:00:24 PM2/8/12
to
On 08/02/2012 20:43, Shawn Wilson wrote:
> On Feb 7, 1:19 pm, Andrew Swallow<am.swal...@btinternet.com> wrote:
>> On 07/02/2012 17:24, dumpst...@hotmail.com wrote:
>>
>>> US Navy testing railgun prototype:
>>
>>> http://www.defenceweb.co.za/index.php?option=com_content&view=article.
>>
>> A possible 220 nm - I hope they have some sort of guidance system in the
>> shell. Even at 50 nautical miles they are over the horizon.
>
>
> "The first industry-built launcher, a 32-megajoule prototype
> demonstrator made by BAE Systems, arrived at Naval Surface Warfare
> Centre (NSWC) Dahlgren, Virginia, on January 30."
>
> 32 Megajoules? That's IT??? A BATTLESHIP main gun (specifically the
> Iowa's) produces 290+ megajoules*. 32 is little more than a tank
> cannon produces. (well, about 3/2 x)
>
> *the formula being 1/2 x mass (kilos) x velocity^2 (meters/second).
>
>

So the shells for this frigate are smaller than those of a WW2
battleship but have a longer range 50nm V. 20nm.

Bigger guns are already being planned, if the Navy wants them.

Andrew Swallow

Shawn Wilson

unread,
Feb 8, 2012, 4:09:08 PM2/8/12
to
On Feb 8, 2:00 pm, Andrew Swallow <am.swal...@btinternet.com> wrote:

> > "The first industry-built launcher, a 32-megajoule prototype
> > demonstrator made by BAE Systems, arrived at Naval Surface Warfare
> > Centre (NSWC) Dahlgren, Virginia, on January 30."
>
> > 32 Megajoules?  That's IT???  A BATTLESHIP main gun (specifically the
> > Iowa's) produces 290+ megajoules*.  32 is little more than a tank
> > cannon produces.  (well, about 3/2 x)
>
> > *the formula being 1/2 x mass (kilos) x velocity^2 (meters/second).
>
> So the shells for this frigate are smaller than those of a WW2
> battleship but have a longer range 50nm V. 20nm.



Eh. Projectile technology has improved ranges greatly, and I imagine
this has a higher muzzle velocity than an Iowa. But, 32 megajoules is
not a lot for a naval cannon. Well, maybe for today, when the
alternative is what, a 5 inch gun? Definitely not in 'battleship'
leagues anyway.




>
> Bigger guns are already being planned, if the Navy wants them.
>
> Andrew Swallow
>
>
>
> > Approximate muzzle energies-
>
> > Iowa- 290 million (per gun)
>
> > Abrahms- 20 million
>
> > 9mm or .45 pistol- 500 (no, not million... just 500)
>
> > .357 or 10mm pistol- 700
>
> > M-16A2 or AK-47- 1800
>
> > M-1 rifle- 3000
>
> > .50 BMG- 18,000- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -

Daryl

unread,
Feb 8, 2012, 8:48:11 PM2/8/12
to
On 2/8/2012 2:00 PM, Andrew Swallow wrote:
> On 08/02/2012 20:43, Shawn Wilson wrote:
>> On Feb 7, 1:19 pm, Andrew Swallow<am.swal...@btinternet.com>
>> wrote:
>>> On 07/02/2012 17:24, dumpst...@hotmail.com wrote:
>>>
>>>> US Navy testing railgun prototype:
>>>
>>>> http://www.defenceweb.co.za/index.php?option=com_content&view=article.
>>>>
>>>
>>> A possible 220 nm - I hope they have some sort of guidance
>>> system in the
>>> shell. Even at 50 nautical miles they are over the horizon.
>>
>>
>> "The first industry-built launcher, a 32-megajoule prototype
>> demonstrator made by BAE Systems, arrived at Naval Surface Warfare
>> Centre (NSWC) Dahlgren, Virginia, on January 30."
>>
>> 32 Megajoules? That's IT??? A BATTLESHIP main gun (specifically
>> the
>> Iowa's) produces 290+ megajoules*. 32 is little more than a tank
>> cannon produces. (well, about 3/2 x)
>>
>> *the formula being 1/2 x mass (kilos) x velocity^2
>> (meters/second).
>>
>>
>
> So the shells for this frigate are smaller than those of a WW2
> battleship but have a longer range 50nm V. 20nm.

The main problem with the old BB was it could fire up to the
curvature of the earth. After that, there was no way to aim it.
Today, smaller guns with better powder have over the horizon
targeting.

They played with the New Jersey Class for longer firing. Two
problems, the targeting and the way the powder was handled.


>
> Bigger guns are already being planned, if the Navy wants them.
>
> Andrew Swallow
>
>> Approximate muzzle energies-
>>
>> Iowa- 290 million (per gun)
>>
>> Abrahms- 20 million
>>
>> 9mm or .45 pistol- 500 (no, not million... just 500)
>>
>> .357 or 10mm pistol- 700
>>
>> M-16A2 or AK-47- 1800
>>
>> M-1 rifle- 3000
>>
>> .50 BMG- 18,000
>>
>>
>>
>>
>


--
http://tvmoviesforfree.com
for free movies and Nostalgic TV. Tons of Military shows and
programs.

dump...@hotmail.com

unread,
Feb 8, 2012, 11:20:11 PM2/8/12
to
On Feb 8, 5:48 pm, Daryl <dh...@nospami70west3.com> wrote:

>
> The main problem with the old BB was it could fire up to the
> curvature of the earth.  After that, there was no way to aim it.
>   Today, smaller guns with better powder have over the horizon
> targeting.
>
> They played with the New Jersey Class for longer firing.  Two
> problems, the targeting and the way the powder was handled.
>

Didn't the BB's carry float-planes for longer-range targeting?

I remember the New Jerseys using SpySats for shell-spotting
in Lebanon. But SpySats aren't always in the proper position
when you need them.

After that, they were were fitted out for UAV operations, which
lead to the 1st case of people surrendering to a UAV during
Operation Desert Storm.

Dan

unread,
Feb 8, 2012, 11:50:26 PM2/8/12
to
On 2/8/2012 10:20 PM, dump...@hotmail.com wrote:
> On Feb 8, 5:48 pm, Daryl<dh...@nospami70west3.com> wrote:
>
>>
>> The main problem with the old BB was it could fire up to the
>> curvature of the earth. After that, there was no way to aim it.
>> Today, smaller guns with better powder have over the horizon
>> targeting.
>>
>> They played with the New Jersey Class for longer firing. Two
>> problems, the targeting and the way the powder was handled.
>>
>
> Didn't the BB's carry float-planes for longer-range targeting?
>

The South Dakota class carried 3. The Iowa class didn't carry any.
The problem with the spotter aircraft was recovery was time consuming
and very difficult in heavier seas.

bill

unread,
Feb 9, 2012, 3:46:26 AM2/9/12
to
On Wed, 08 Feb 2012 13:09:08 -0800, Shawn Wilson wrote:

> On Feb 8, 2:00 pm, Andrew Swallow <am.swal...@btinternet.com> wrote:
>
>> > "The first industry-built launcher, a 32-megajoule prototype
>> > demonstrator made by BAE Systems, arrived at Naval Surface Warfare
>> > Centre (NSWC) Dahlgren, Virginia, on January 30."
>>
>> > 32 Megajoules?  That's IT???  A BATTLESHIP main gun (specifically the
>> > Iowa's) produces 290+ megajoules*.  32 is little more than a tank
>> > cannon produces.  (well, about 3/2 x)
>>
>> > *the formula being 1/2 x mass (kilos) x velocity^2 (meters/second).
>>
>> So the shells for this frigate are smaller than those of a WW2
>> battleship but have a longer range 50nm V. 20nm.
>
>
>
> Eh. Projectile technology has improved ranges greatly, and I imagine
> this has a higher muzzle velocity than an Iowa. But, 32 megajoules is
> not a lot for a naval cannon. Well, maybe for today, when the
> alternative is what, a 5 inch gun? Definitely not in 'battleship'
> leagues anyway.

Look at the theoretical rate of fire and range for this stiff and compare
it to a battleship main battery shooting one savlo every 20 or 30 seconds.

It's not just about weight of shell...

Come to think of it, it hasn't been since they came up with the
carronade...

And try and learn to spell Sean...

Chris

unread,
Feb 9, 2012, 1:44:04 PM2/9/12
to
On Feb 8, 11:20 pm, dumpst...@hotmail.com wrote:

> Didn't the BB's carry float-planes for longer-range targeting?

Yes, until Spring '45 the Iowa's carried 3 OS2U Kingfisher's, as did
the earlier ships. They were pulled off the New Jersey in spring '45,
but some ships maintained them at least to 1948- I've seen pictures of
a SC-1 operating off USS Manchester in 1948, so at least some of the
Cleveland's kept their's after the war.

I think that the battleline ships all got airplanes during their
1930's rebuilds in the USN. I don't know when the RN or IJN added them
to their ships, but I would guess about the same time.

> I remember the New Jerseys using SpySats for shell-spotting
> in Lebanon.  But SpySats aren't always in the proper position
> when you need them.

This seems unlikely to me. Simple back of the envelope calculations
show that a spy-sat in low earth orbit should be visible for about 6
minutes at the absolute most, and then not visible again for another
~85 minutes. And if the existing orbit does take the spy-sat directly
overhead- to maximize single pass observation time- then it will be
barely visible over the horizon on its next pass, so you will need to
wait another 24 hours for it to pass overhead again in daylight.

Neglecting air resistance, a single max range salvo would take
approximately two minutes to fall (due to air resistance it will be
less, but that's about the right order of magnitude- at best it'll be
~90 seconds or so). So you could get in just four correction cycles,
at the absolute best[1], which just isn't enough to get an accurate
hit on a target like a small ground installation as New Jersey was
hunting in 1983-4.

Now with maneuvering you could change the exposure time, to some
extent- maybe add a minute or two in one orbit, but the fuel of a
spysat is its most important limiting factor, and it would be an
expensive use of an incredibly valuable strategic asset for a minor
tactical gain to use it to spot the fall of shells on some SAM sites.
It wouldn't surprise me if they timed the shelling so that a KH-11
would pass over shortly afterwards for BDA, but I seriously doubt that
it was being used in real time by BB-62 to correct the fall of shot.

[1]: Note that bandwidth was much more limited in 1983- the Iowas did
have a SATCOM voice link, but that's about it. I'm neglecting any
communication delays in this back-of-the-envelope calculations, but it
would be a problem in the real world.

Chris Manteuffel

Jim Wilkins

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Feb 9, 2012, 2:23:01 PM2/9/12
to

"Chris" <cman...@gmail.com> wrote in message news:ddd0305b-332a-4d4c-95ed-
>...
>It wouldn't surprise me if they timed the shelling so that a KH-11
>would pass over shortly afterwards for BDA, but I seriously doubt that
>it was being used in real time by BB-62 to correct the fall of shot....

Chris Manteuffel

USS New Jersey used RQ-2 Pioneer UAVs for spotting. AFAIK the problem was
the enormous collateral damage the first few uncorrected shells create. The
Wiki claims an error of as much as 9 km.
http://en.wikipedia.org/wiki/USS_New_Jersey_(BB-62)

jsw


Bill Shatzer

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Feb 9, 2012, 3:38:58 PM2/9/12
to
Chris wrote:


> I think that the battleline ships all got airplanes during their
> 1930's rebuilds in the USN. I don't know when the RN or IJN added them
> to their ships, but I would guess about the same time.

Catapults were fitted to USS Nevada, Oklahoma, and Maryland in 1922.

By 1926, all the oil burning BBs had been so fitted.

For budgetary reasons, the installation of catapults on the coal burners
(New York class, etc.) was put off pending their reconstruction and
conversion to oil but even that was largely completed by 1930.

Chris

unread,
Feb 9, 2012, 4:29:51 PM2/9/12
to
Thanks!

Chris Manteuffel

Rob Arndt

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Feb 12, 2012, 1:48:04 AM2/12/12
to
Bull stole from German Third Reich ideas and railway guns. Peenemunde,
btw, had a design for a 15cm EM railgun with all flight projectiles
wind tunnel tested!!!

Repost from 2007:

http://www.ww2technik.de/Bilderchen/sonstiges/railgun%20projectile%20...

http://www.ww2technik.de/Bilderchen/sonstiges/railgun%20projectile%20...

By 1944 some theoretical research was started at Peenemunde regarding
a 15cm railgun with a rate of fire of 200 rpm using a 100 kW
powerplant and also a 4cm AA-railgun.

Several radical aircraft-shaped projectiles were tested in 1945 for
the AA-railgun but the power supply was problematic. A suitable
battery or condensator had a very high weight (600 -3,000 tons)
making
the gun immobile.

More on the 4cm gun:

http://www.lonesentry.com/articles/electricgun/german_electric_gun_secretweapons_may46.jpg


THE ELECTRIC GUN
German Experiment With Electrically Launched Projectiles

--------------------------------------------------------------------------------

A super-high-velocity gun, operating on electrical energy instead of
an explosive propellant, has been a minor scientific dream for some
time. The idea is not new; for it was tried by the French in World
War
I. But in World War II, a German scientist felt he was so close to a
solution of the problems involved that the German Air Force had
contracted for an experimental electric gun. This gun was to be
capable of ejecting a 40-mm projectile at a muzzle velocity of 6,600
feet per second-far above the velocity of any shell yet fired from a
conventional artillery piece.

Although the gun ordered was not delivered before the end of the war,
a miniature that actually worked was built and tested. Theoretical
calculations, based upon tests made with the miniature gun, led the
German scientists to believe it possible to build an electric gun
capable of tossing a 14-pound projectile to an altitude of 12 miles
in
13 seconds.

To men familiar with the problems of antiaircraft artillery, such a
weapon appeared a godsend. The 90-mm antiaircraft gun of
conventional,
powder-burning design, can reach only 4.4 miles in altitude in the
same length of time.

THE DESIGN

Although the problem of electrically ejected shells is an old one, it
has still to pass the research stages. The chief problem is to obtain
a source of sufficient electrical power that will not be all out of
proportion to the size of the gun. Designing a gun did not seem to be
too great a problem, for the German model appeared logical.

The German gun, had it ever been built to full scale, would have had
a
rectangular barrel 33.7 feet long. The round bore, as designed by the
Germans, is flanked by two, square grooves 180 degrees apart, so that
when the bore is seen from one end, it is the same shape as the
aircraft identification insignia used by the U.S. Army Air Forces.
The
bore is not rifled. At the extreme ends of the two grooves, an
insulated, copper glide rail runs the entire length of the barrel. It
is through these glide rails that the electrical energy is conducted
for ejecting the shell.

The shell is a cylindrical projectile somewhat longer than the
conventional artillery shell, and has four narrow fins at its base.
It
is fitted with a cradle, called a "glide wing," from which extend two
studs which fit into the square grooves of the bore, and ride on the
copper glide rails. After the shell has been placed in the gun, a
jolt
of electricity is shot into the weapon. The current, passing along
the
glide rails and through the glide wing, sets up an intense magnetic
field. The reaction is such that the magnetic field and the current
flow through the glide rails tend to repel each other. This, in
effect, forces the projectile up the bore at an ever increasing
velocity until, when it leaves the muzzle, it is traveling at a
terrific rate of speed. This reaction is so fast that it is only a
matter of a split second between the introduction of the current and
the ejection of the shell from the gun.

Rob

Dan

unread,
Feb 12, 2012, 2:59:08 AM2/12/12
to
On 2/12/2012 12:48 AM, Rob Arndt wrote:
> Bull stole from German Third Reich ideas and railway guns.

He didn't steal anything, he simply built on prior technology just as
the Germans did. The Germans didn't invent gunpowder, ballistics, steel,
railroads etc.

Unless you can come up with anything the Germans created out of
nothing you simply weaken your arguments when you use terms like stole
and raped as is your wont.

Dan

unread,
Feb 12, 2012, 3:00:17 AM2/12/12
to
On 2/12/2012 12:48 AM, Rob Arndt wrote:
> Peenemunde,
> btw, had a design for a 15cm EM railgun with all flight projectiles
> wind tunnel tested!!!

Big deal, they never built the thing. The theory predates the Nazis.

Daryl

unread,
Feb 12, 2012, 4:27:53 AM2/12/12
to
On 2/11/2012 11:48 PM, Rob Arndt wrote:
> Bull stole from German Third Reich ideas and railway guns. Peenemunde,
> btw, had a design for a 15cm EM railgun with all flight projectiles
> wind tunnel tested!!!

I guess since Germany invaded France, Louis Octave
Fauchon-Villeplee would now be considered German, Right? patent
no. 1,421,435 "Electric Apparatus for Propelling Projectiles".

Let's also not count out the Norwegians in 1901. But the patent
is from the French in 1918. Oh, wait, that's right, Norway was
invaded as well that would make their work also German.

Rob Arndt

unread,
Feb 13, 2012, 2:56:19 AM2/13/12
to
You failed miserably with Bull b/c due to HIS OWN ADMISSION he was
obssessed with the WW1 German Paris Guns and searched all of Europe
for every scrap on intelligence about them and then he used computer
models to simulate modern versions of them of various calibers to
arrive at a cannon as big as Project Babylon. He considered the HARP
guns descendents of German tech.

~ "Arms and the Man" by William Lowther pgs 154-155

Who built the Paris Guns? Krupp. And during WW2 even longer range
guns appeared like the K5 with rocket-assited shells and the V-3
weapon. US postwar gun tech came from German tech. You lose.

Germany also built the Hansler prototype 40mm lab electric gun during
WW2. Not a concept but a real prototype AA gun.

Since the Germans also built the greatest guns of all time, the 3
million lb 80cm Gustav and Dora... they could have built Bull's
Babylon gun in the 1940s!!!

Rob

Dan

unread,
Feb 13, 2012, 3:07:29 AM2/13/12
to
OK, so the Germans invented metallurgy, gun powder, higher level
mathematics, ballistics, electrical science etc? If not they learned
from others. You need to get a grasp on reality. Bull got his ideas from
the Germans, but he didn't steal them as you claim.

Dan

unread,
Feb 13, 2012, 3:13:51 AM2/13/12
to
On 2/13/2012 1:56 AM, Rob Arndt wrote:
> Since the Germans also built the greatest guns of all time, the 3
> million lb 80cm Gustav and Dora... they could have built Bull's
> Babylon gun in the 1940s!!!

When you speak in absolutes you need to be able to prove it. You are
entitled to your opinion, but many of us disagree. In any event the big
guns to which you refer were military flops. They took too long to set
up and take down, had such limited use as to be a waste of manpower and
resources. None had any significant impact on any battle.

Rob Arndt

unread,
Feb 13, 2012, 5:08:25 AM2/13/12
to
The 80cm that shelled Sevastapol took out their massive defenses with
ease and the multitude of various caliber German railway guns were
quite effective shelling out to various locations. Had the V-3 HDP
guns become operational there would have been no need for the LW over
Britain b/c it would have rained shells for hours at a time and
devastated entire sections of English cities. Also, the victorious
Allies disagree with you and took as many railway guns as they could
find for themselves and also the US tested several for ballistic
research postwar as well as analyzed the Peenemunde and other
facilities projectiles, missiles, and EM designs. von Braun did more
than disclose on the V-2 and variants.

So you are a liar.

Rob

Jim Wilkins

unread,
Feb 13, 2012, 7:10:31 AM2/13/12
to

"Dan" <B24...@aol.com> wrote in message
news:L8qdnQL_2vpeWaXS...@giganews.com...
> On 2/13/2012 1:56 AM, Rob Arndt wrote:
>> ...Bull got his ideas from
> the Germans, but he didn't steal them as you claim.
>
> Dan, U.S. Air Force, retired

The Germans had stolen the idea from the French:
http://en.wikipedia.org/wiki/From_the_Earth_to_the_Moon

"In his 1903 publication on space travel, Konstantin Tsiolkovsky refuted
Verne's idea of using a cannon for space travel. He concluded that a gun
would have to be impossibly long. The gun in the story would subject the
payload to about 22000 g of acceleration (see formula). However, he was
nevertheless inspired by the story and developed the theory of spaceflight.
Gerald Bull and the Project HARP proved after 1961 that a cannon can shoot a
180 kg (400 lb) projectile to an altitude of 180 kilometres (110 mi) and
reach 32 percent of the needed escape velocity."

jsw


Jim Wilkins

unread,
Feb 13, 2012, 7:21:53 AM2/13/12
to
"Rob Arndt" <teut...@aol.com> wrote
>...
>The 80cm that shelled Sevastapol ...
>Rob

These inferior substitutes only highlight the complete failure to produce an
effective strategic bombing force.

jsw


Keith W

unread,
Feb 13, 2012, 8:08:44 AM2/13/12
to
Rob Arndt wrote:
> On Feb 13, 12:13 am, Dan <B24...@aol.com> wrote:
>> On 2/13/2012 1:56 AM, Rob Arndt wrote:
>>
>>> Since the Germans also built the greatest guns of all time, the 3
>>> million lb 80cm Gustav and Dora... they could have built Bull's
>>> Babylon gun in the 1940s!!!
>>
>> When you speak in absolutes you need to be able to prove it. You are
>> entitled to your opinion, but many of us disagree. In any event the
>> big guns to which you refer were military flops. They took too long
>> to set up and take down, had such limited use as to be a waste of
>> manpower and resources. None had any significant impact on any
>> battle.
>>
>> Dan, U.S. Air Force, retired
>
> The 80cm that shelled Sevastapol took out their massive defenses with
> ease and the multitude of various caliber German railway guns were
> quite effective shelling out to various locations.

It took the Heer from November 1941 to July 1942 to take the
city. The part played by the large guns was secondary, in the
end the Soviet resistance collapsed when they ran out of ammunition


> Had the V-3 HDP
> guns become operational there would have been no need for the LW over
> Britain b/c it would have rained shells for hours at a time and
> devastated entire sections of English cities.

Of course those spoilsports in the RAF made sure that didnt happen
by dropping the really useful heavy hitters of the ETO, namely
Tallboy and Grandslam on the site


> Also, the victorious
> Allies disagree with you and took as many railway guns as they could
> find for themselves

Not true old son. Lets look at what happened to the 80 cm rail guns

Schwerer Gustav - fired less than 50 shells. In total the German
army had fired over 30,000 tons of artillery shells into Sevastopol.
The gun never fired in anger again and was destroyed by the Germans

Dora - Doesnt seem to have ever fired a single shot in anger
and was captured in a ruined state in 1945

Each of these guns required 500 men to fire it and a full
construction brigade of 2,500 men to prepare the site for
its deployment.

In the case of Sevastopol the city was besieged in Nov 1941
and the first gun wasnt in place until June as the German army
had to build a special rail spur to move it into position and of course
special constructed sidings were needed to aim the beast.
This took between 3 and 6 weeks even if the enemy didnt
interfere.

Dora was sent to Stalingrad but didnt get put in place until
September when it had to be quickly withdrawn before
it was ready to be fired to avoid being overrun by the Soviets

> and also the US tested several for ballistic
> research postwar

Several as in ONE that was built using the remains of the K5 11"
rail guns Robert and Leopold, better known by their Allied nicknames
- Anzio Annie and Anzio Express. They were of course ineffectual
and the Germans would have been far better off with a battery
of 150 mm conventional guns. The only role in which they were
at all useful was as coastal artillery in the Calais area.

> as well as analyzed the Peenemunde and other
> facilities projectiles, missiles, and EM designs. von Braun did more
> than disclose on the V-2 and variants.
>
> So you are a liar.
>
> Rob

Pot Kettle Black

Keith


Keith W

unread,
Feb 13, 2012, 8:14:35 AM2/13/12
to
Jim Wilkins wrote:
> "Dan" <B24...@aol.com> wrote in message
> news:L8qdnQL_2vpeWaXS...@giganews.com...
>> On 2/13/2012 1:56 AM, Rob Arndt wrote:
>>> ...Bull got his ideas from
>> the Germans, but he didn't steal them as you claim.
>>
>> Dan, U.S. Air Force, retired
>
> The Germans had stolen the idea from the French:
> http://en.wikipedia.org/wiki/From_the_Earth_to_the_Moon
>

As it happens the first country to mount a heavy artillery piece on a
a railway car and use it in combat was the CSA when General
Robert E. Lee had a 32 pounder mounted on a rail car
moved into position for the Battle of Savage's Station

Keith


Jim Wilkins

unread,
Feb 13, 2012, 8:58:18 AM2/13/12
to

"Keith W" <keithnosp...@demon.co.uk> wrote in message
news:418_q.46880$2t3....@newsfe09.ams2...
> Jim Wilkins wrote:
>> The Germans had stolen the idea from the French:
>> http://en.wikipedia.org/wiki/From_the_Earth_to_the_Moon
>>
>
> As it happens the first country to mount a heavy artillery piece on a
> a railway car and use it in combat was the CSA when General
> Robert E. Lee had a 32 pounder mounted on a rail car
> moved into position for the Battle of Savage's Station
> Keith

That and other examples:
http://www.firstmdus.net/Rail%20cars.htm
Though armored mobile artillery goes back at least to the ancient Greeks.

The technology leaps of the American Civil War were mostly improvised
expedients since the US expected and was equipped for frontier battles
beyond the reach of easy transport. The authorities often misunderstood and
rejected new developments, some of which like the Monitor-type warship and
lever-action repeating rifle really were dead ends.

jsw


dott.Piergiorgio

unread,
Feb 13, 2012, 10:02:52 AM2/13/12
to

> The Germans had stolen the idea from the French:
> http://en.wikipedia.org/wiki/From_the_Earth_to_the_Moon
>
> "In his 1903 publication on space travel, Konstantin Tsiolkovsky refuted
> Verne's idea of using a cannon for space travel. He concluded that a gun
> would have to be impossibly long. The gun in the story would subject the
> payload to about 22000 g of acceleration (see formula). However, he was
> nevertheless inspired by the story and developed the theory of spaceflight.
> Gerald Bull and the Project HARP proved after 1961 that a cannon can shoot a
> 180 kg (400 lb) projectile to an altitude of 180 kilometres (110 mi) and
> reach 32 percent of the needed escape velocity."

[socratic question !]

and the range was... ?

hint: low density of high atmosphere

Best regards from Italy,
dott. Piergiorgio.

Dan

unread,
Feb 13, 2012, 10:07:04 AM2/13/12
to
On 2/13/2012 4:08 AM, Rob Arndt wrote:
> On Feb 13, 12:13 am, Dan<B24...@aol.com> wrote:
>> On 2/13/2012 1:56 AM, Rob Arndt wrote:
>>
>>> Since the Germans also built the greatest guns of all time, the 3
>>> million lb 80cm Gustav and Dora... they could have built Bull's
>>> Babylon gun in the 1940s!!!
>>
>> When you speak in absolutes you need to be able to prove it. You are
>> entitled to your opinion, but many of us disagree. In any event the big
>> guns to which you refer were military flops. They took too long to set
>> up and take down, had such limited use as to be a waste of manpower and
>> resources. None had any significant impact on any battle.
>>
>> Dan, U.S. Air Force, retired
>
> The 80cm that shelled Sevastapol took out their massive defenses with
> ease

But the firing rate was so low it was over shadowed by bombers.
Sevastopol would have been taken just as quickly without the big gun.


and the multitude of various caliber German railway guns were
> quite effective shelling out to various locations.

True, but none were game changers. Every one of the guns used more
resources than was justified by the effect achieved.


Had the V-3 HDP
> guns become operational there would have been no need for the LW over
> Britain b/c it would have rained shells for hours at a time and
> devastated entire sections of English cities.

Big deal, it was never operational so why bring it into the equation?

Also, the victorious
> Allies disagree with you and took as many railway guns as they could
> find for themselves and also the US tested several for ballistic
> research postwar as well as analyzed the Peenemunde and other
> facilities projectiles, missiles, and EM designs.

Which only proves the Allies wanted to test them. In case you haven't
noticed, with the exception of Atomic Annie, no one has fielded a big
gun since WW2. Atomic Annie was also a flop.

von Braun did more
> than disclose on the V-2 and variants.
>
> So you are a liar.

Which you have yet to prove.
>
> Rob

Jim Wilkins

unread,
Feb 13, 2012, 10:51:54 AM2/13/12
to

"dott.Piergiorgio" <chied...@ask.me> wrote
>> Gerald Bull and the Project HARP proved after 1961 that a cannon can
>> shoot a
>> 180 kg (400 lb) projectile to an altitude of 180 kilometres (110 mi) and
>> reach 32 percent of the needed escape velocity."
>
> [socratic question !]
>
> and the range was... ?
>
> hint: low density of high atmosphere
> dott. Piergiorgio.

Artificially limited by his low-budget facilities. Without drag a WW1 rifle
bullet would have a maximum range of over 60 kilometers, with it the range
is less than 6 km.

The US government has the same problem, we had to use Kwajalein lagoon as
the ICBM target because the USSR wouldn't let us practice there.

jsw


Jim Yanik

unread,
Feb 13, 2012, 11:15:31 AM2/13/12
to
"dott.Piergiorgio" <chied...@ask.me> wrote in
news:xC9_q.134976$GZ3....@tornado.fastwebnet.it:
in Heinlein's book The Moon is a Harsh Mistress(great book),he mentions
building an electromagnetic catapult(BIG coilgun) on a high mountain,to get
above much of the atmosphere,reducing drag and altitude gain needed to
reach orbit. He powered it with nuclear reactors.He also knew the catapult
had to be very long.

TANSTAAFL. ;-)

--
Jim Yanik
jyanik
at
localnet
dot com

Jim Wilkins

unread,
Feb 13, 2012, 11:29:08 AM2/13/12
to

"Rob Arndt" <teut...@aol.com> wrote
>...Had the V-3 HDP
>guns become operational there would have been no need for the LW over
>Britain b/c it would have rained shells for hours at a time and
>devastated entire sections of English cities. ..
>Rob

Hours is how long it would have survived before the RAF counterattacked with
the RIGHT instruments of devastation.

You are fooling only yourself by pretending that the Germans didn't really
need those decisive Allied weapons which they couldn't match, most notably
strategic bombers and naval forces sufficient to repel an invasion. When the
reality of defeat loomed the Germans fell back on what they knew, elaborate
toys and Magic Bullets.

BTW the devil controls the Magic Bullets.

jsw


Daryl

unread,
Feb 13, 2012, 11:30:30 AM2/13/12
to
Funny you bring that up. One of the projects for lifting ore and
precious metals from the moon involves a Catapult. Makes sense
and it would be cheap to operate. Just get it to low moon orbit
and pick it up there.

Dan

unread,
Feb 13, 2012, 11:46:55 AM2/13/12
to
On 2/13/2012 9:51 AM, Jim Wilkins wrote:
> The US government has the same problem, we had to use Kwajalein lagoon as
> the ICBM target because the USSR wouldn't let us practice there.
>
> jsw
>

That's just gauche. Just think of all the empty land the Soviets had
and chasing missile parts would have kept the Soviets busy.

Jim Wilkins

unread,
Feb 13, 2012, 11:54:01 AM2/13/12
to

"Jim Yanik" <jya...@abuse.gov> wrote in message
news:Xns9FF872ADFBA7C...@216.168.3.44...
> "dott.Piergiorgio" <chied...@ask.me> wrote..
> in Heinlein's book The Moon is a Harsh Mistress(great book),he mentions
> building an electromagnetic catapult(BIG coilgun) on a high mountain,to
> get
> above much of the atmosphere,reducing drag and altitude gain needed to
> reach orbit. He powered it with nuclear reactors.He also knew the catapult
> had to be very long.

You'd need at least three minutes of barely tolerable acceleration on a
track several =hundred= km long to reach the minimum orbital velocity of ~7
km/s.
http://en.wikipedia.org/wiki/StarTram

jsw


Jim Wilkins

unread,
Feb 13, 2012, 12:45:55 PM2/13/12
to

"Jim Wilkins" <murat...@gmail.com> wrote in message
news:jhbf60$okl$1...@dont-email.me...
>
> You'd need at least three minutes of barely tolerable acceleration on a
> track several =hundred= km long to reach the minimum orbital velocity of
> ~7 km/s.
> http://en.wikipedia.org/wiki/StarTram
>
> jsw

I started to calculate the track length for various levels of "tolerable"
acceleration but this would be a good project for Tucker to demonstrate his
rocket scientist skills. Don't forget the delta-v lost while coasting up to
200 km. You have enough rocket fuel to circularize the orbit.
http://en.wikipedia.org/wiki/Hohmann_transfer_orbit

jsw


Andrew Swallow

unread,
Feb 13, 2012, 4:28:15 PM2/13/12
to
Such guns may get used on Mars and the Moon. Unfortunately no mountain
on Earth is sufficiently tall.

Andrew Swallow

Jim Yanik

unread,
Feb 14, 2012, 9:26:38 PM2/14/12
to
Andrew Swallow <am.sw...@btinternet.com> wrote in
news:64Cdnaqt_9byHaTS...@bt.com:
Sez who? the goal is to get above MUCH of the atmosphere,not all of it.

Andrew Swallow

unread,
Feb 14, 2012, 9:53:44 PM2/14/12
to
Do some air resistance calculations at orbital speeds and the energies
needed. Earth and those speeds do not mix.

Andrew Swallow

David E. Powell

unread,
Feb 14, 2012, 10:05:17 PM2/14/12
to
The trick to get a shell out of the atmosphere would be to use a
rocket boosted shell. Even base bleed might not do it alone. Get up
where the air is thin, then kick in the motor.

Paul J. Adam

unread,
Feb 15, 2012, 3:35:21 AM2/15/12
to
On 15/02/2012 02:26, Jim Yanik wrote:
>> Such guns may get used on Mars and the Moon. Unfortunately no
>> mountain on Earth is sufficiently tall.
>
> Sez who?

The laws of physics. Check out escape velocity from the top of Everest,
then calculate atmospheric drag on a body moving at that speed.

> the goal is to get above MUCH of the atmosphere,not all of it.

And you can't do that without building so high, you might as well finish
the climb and get a Clarke-style space elevator.


--
He thinks too much, such men are dangerous.

Keith W

unread,
Feb 15, 2012, 3:41:46 AM2/15/12
to
Which brings us neatly back to Dr Bull and HARP which in 1966
managed to get a projectile up to 112 miles high

http://en.wikipedia.org/wiki/Project_HARP

Keith


Jim Wilkins

unread,
Feb 15, 2012, 10:42:17 AM2/15/12
to

"Andrew Swallow" <am.sw...@btinternet.com> wrote
> On 15/02/2012 02:26, Jim Yanik wrote:
>> Andrew Swallow<am.sw...@btinternet.com> wrote in
>>> On 13/02/2012 16:15, Jim Yanik wrote:
>>>> "dott.Piergiorgio"<chied...@ask.me> wrote in
>>>>
>>>
>>
>> Sez who? the goal is to get above MUCH of the atmosphere,not all of it.
>
> Do some air resistance calculations at orbital speeds and the energies
> needed. Earth and those speeds do not mix.
>
> Andrew Swallow

Columbia burned up at somewhat less than orbital velocity and 61 km,
>200,000 feet. Tall mountains near the equator like Kilamanjaro and
Chimborazo are only a tenth that high.

jsw


Alexander Schreiber

unread,
Feb 15, 2012, 5:08:41 PM2/15/12
to
Rob Arndt <teut...@aol.com> wrote:
> On Feb 13, 12:13 am, Dan <B24...@aol.com> wrote:
>> On 2/13/2012 1:56 AM, Rob Arndt wrote:
>>
>> > Since the Germans also built the greatest guns of all time, the 3
>> > million lb 80cm Gustav and Dora... they could have built Bull's
>> > Babylon gun in the 1940s!!!
>>
>>    When you speak in absolutes you need to be able to prove it. You are
>> entitled to your opinion, but many of us disagree. In any event the big
>> guns to which you refer were military flops. They took too long to set
>> up and take down, had such limited use as to be a waste of manpower and
>> resources. None had any significant impact on any battle.
>>
>> Dan, U.S. Air Force, retired
>
> The 80cm that shelled Sevastapol took out their massive defenses with
> ease and the multitude of various caliber German railway guns were
> quite effective shelling out to various locations.

Yes, the 80 cm gun was rather impressive when flattening the fortress
Sevastopol. However it required not only an enormous amount of resources
to be built, but also an incredible amount of infrastructure to use it.

Purely from a technical perspective: impressive gadget. But from a military
effective impact per buck perspective: a massive failure.

> Had the V-3 HDP
> guns become operational there would have been no need for the LW over
> Britain b/c it would have rained shells for hours at a time and
> devastated entire sections of English cities.

Riight. Except the test setup blew up after less then 50 rounds fired,
and in the case were (much shortened) versions were actually firing on
a city sized target (and hitting it), the damage was minimal for the effort
involved. Given the small payload of less than 10 kg of HE in that case,
that is not surprising.

Assuming - for the sake of the argument - that the HDP had been built and
would have worked as intended: there is still the problem of it being a
static, non-movable ground installation. It wouldn't have taken long for it
to be bombed out of service. And in fact, the construction site _was_ put
out of commission by RAF bombers.

Kind regards,
Alex.
--
"Opportunity is missed by most people because it is dressed in overalls and
looks like work." -- Thomas A. Edison

Jim Yanik

unread,
Feb 15, 2012, 5:16:29 PM2/15/12
to
Andrew Swallow <am.sw...@btinternet.com> wrote in
news:jqCdnfUPq4Wmg6bS...@bt.com:
odd,current rockets seem to accellerate and overcome the same air
resistance at higher altitudes.

if you want calculations,you do them. show your work.

Dan

unread,
Feb 15, 2012, 5:44:15 PM2/15/12
to
Apples and oranges, a rocket maintains thrust, a cannon or other gun
needs to generate all the thrust the projectile is going to get by the
time it exits the muzzle. A cannon projectile will be slowing down from
the instant it exits the muzzle due to air resistance and gravity.
Inertia is another thing. A rocket loses mass as it burns fuel, a cannon
projectile maintains mass. Thus for a given thrust a rocket can accelerate.

Andrew Swallow

unread,
Feb 15, 2012, 5:46:21 PM2/15/12
to
Rockets accelerate up to the speed of a riffle bullet in the atmosphere.
They continue to accelerate by burning fuel when out of the atmosphere.

Bullets and shells stop accelerating when they leave the barrel of the
gun. The atmosphere then slows them down.

Andrew Swallow

Jim Wilkins

unread,
Feb 15, 2012, 5:48:31 PM2/15/12
to
"Alexander Schreiber" <a...@usenet.thangorodrim.de> wrote in message
>
> Riight. Except the test setup blew up after less then 50 rounds fired,
> and in the case were (much shortened) versions were actually firing on
> a city sized target (and hitting it), the damage was minimal for the
> effort
> involved. Given the small payload of less than 10 kg of HE in that case,
> that is not surprising....
>
> Alex.

In 1880 James Haskell and Azel Lyman tested a hypervelocity gun design at
Frankfort Arsenal in Philadelphia, based on multiple booster charges
distributed down the extremely long barrel, which was supported on a ramp.
It had sealing problems like the later Paris Gun that needed successively
larger diameter shells to compensate for rapid barrel wear.

http://www.firstworldwar.com/source/parisgun_pressreport.htm

jsw


Paul J. Adam

unread,
Feb 15, 2012, 6:34:48 PM2/15/12
to
On 15/02/2012 22:16, Jim Yanik wrote:
> Andrew Swallow<am.sw...@btinternet.com> wrote in
> news:jqCdnfUPq4Wmg6bS...@bt.com:
>> Do some air resistance calculations at orbital speeds and the energies
>> needed. Earth and those speeds do not mix.

> odd,current rockets seem to accellerate and overcome the same air
> resistance at higher altitudes.

Rockets do, unpowered projectiles don't.

Which is why (multi-stage) rockets can achieve orbit for a small
payload, and unpowered projectiles launched from ground level (even very
high ground)... can't.

Jim Wilkins

unread,
Feb 15, 2012, 6:38:37 PM2/15/12
to

"Jim Yanik" <jya...@abuse.gov> wrote in message
news:Xns9FFAAFEBF6511...@216.168.3.44...
> ...>
> odd,current rockets seem to accellerate and overcome the same air
> resistance at higher altitudes.
> if you want calculations,you do them. show your work.
> Jim Yanik

The shuttle started slow, 8 seconds to 100 MPH. Maximum aerodynamic pressure
("Max Q") from the combination of increasing speed and decreasing air
density occurred at about one minute after launch, at ~1000 MPH.
http://spaceflight1.nasa.gov/shuttle/reference/basics/launch.html
http://www.aerospaceweb.org/question/aerodynamics/q0025.shtml

Its initially low acceleration increased as it lost fuel weight. Full power
would give a velocity profile that didn't quite match the rate the
atmosphere thins with altitude, so they throttled back the main engines
between 26 and 60 seconds.

jsw


Jim Wilkins

unread,
Feb 15, 2012, 7:52:14 PM2/15/12
to

"Paul J. Adam" <paul....@gmail.com> wrote in message
news:jhhffv$tld$1...@dont-email.me...
> On 15/02/2012 22:16, Jim Yanik wrote:
>> Andrew Swallow<am.sw...@btinternet.com> wrote in
>
>> odd,current rockets seem to accellerate and overcome the same air
>> resistance at higher altitudes.
>
> Rockets do, unpowered projectiles don't.
>
> Which is why (multi-stage) rockets can achieve orbit for a small payload,
> and unpowered projectiles launched from ground level (even very high
> ground)... can't.

Multiple stages solve a different problem, lifting the enormous weight of
fuel that will be burnt to lift mostly other fuel. It's a huge pyramid with
a tiny payload at the top.

The lower stages are like the tankers on the Black Buck missions. They only
had to fly part way and then refuel the Vulcan with their surplus. The
Vulcan couldn't carry enough fuel that far by itself, so the Victors
contributed their lift and thrust to bring along extra fuel to the point
where the Vulcan was within its range.
http://en.wikipedia.org/wiki/File:Refuelling.plan.black.buck.svg

Likewise the heavy lower stages jack the light final one up higher and
faster before it consumes its fuel.

jsw


Jim Yanik

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Feb 16, 2012, 11:34:07 AM2/16/12
to
Andrew Swallow <am.sw...@btinternet.com> wrote in
news:a7ednXtZUMFbqKHS...@bt.com:
rockets going into orbit go a lot faster than a rifle bullet before they
exit atmosphere. rifle bullets are only going about Mach 3(3000 FPS muzzle
velocity)
LE orbital velocity is IIRC,18,000 MPH,and that does not all come from exo-
atmoshere accel.

Jim Wilkins

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Feb 16, 2012, 1:46:20 PM2/16/12
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"Jim Yanik" <jya...@abuse.gov> wrote in message
news:Xns9FFB75E08C849...@216.168.3.44...
> ...
>
> rockets going into orbit go a lot faster than a rifle bullet before they
> exit atmosphere. rifle bullets are only going about Mach 3(3000 FPS muzzle
> velocity)
> LE orbital velocity is IIRC,18,000 MPH,and that does not all come from
> exo-
> atmoshere accel.
> Jim Yanik

I already posted the answer. Here it is again:
http://www.aerospaceweb.org/question/aerodynamics/maxq/maxq.jpg

The red line "V" is the speed of the Shuttle in feet per second, the blue
one "p" [rho] is air density and the green one "h" is altitude. MPH is
roughly 2/3 of fps (60/88).

The black line "q" shows the aerodynamic pressure in Lbs/ft^2 on the launch
vehicle that results from the changing combination of speed and density. It
peaks at around 35,000 feet. Above that the air thins more quickly than the
Shuttle gains speed, so air resistance drops.

The chart ends at 150,000 feet where the Shuttle has reached the speed of a
Remington 30-06 Accelerator bullet and air density and drag are very low.
Columbia had made it down to ~207,000 feet, still at nearly orbital
velocity, when it burned up.

Notice that the Shuttle doesn't quite reach the SR-71's high-altitude
performance.

jsw


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