Re: Has there ever been an off-center gun?

[Jukka O. Kauppinen]

> Wouldn't a gun pointed at a downward angle make ground attack easier?

Many ground attack aircraft have had such configuration, including IL-2.
Not all of them, but in remarkable numbers anyway.

jok

[Peter Stickney]

In article >,
Hobo > writes:
>
> Has there ever been an aircraft with a gun permanently aligned
> off-center? I don't mean swivel mounted, but permanently fixed at a
> point other than straight ahead.

Quite a few, actually. Assuming that you're willing to stipulate teh
defensive guns on bombers ranging from the Be.2C in WW I (ANd yes,
they did drop a few bombs) to the Tu-22M Backfire.

In terms of fighters, It's been done a number of times. The most
mentioned would be the upward-pointing "Shrage Muzik" guns on German
Night Fighters. This allowed them to formate on RAF night bombers in
the one quadrant with no lookouts or guns, and shoot into the largest
possible area - teh entire planform of the aircraft. The Japanese
tried something similar.

> Wouldn't a gun pointed at a downward angle make ground attack easier?

Check out the Junkers-Larson ground attack prototype made for the
U.S. Army in the 1920s. It was basically an all-metal Junkers
monoplane transport with something like 30 .45 Calibre Thomson
Submachineguns firing at vatious angle through the bottom fuselage.
The idea was that it would fly along trench lines at low altitude,
saturating the trenches with bullets. (The opinions of the Gun
Plumber on board who'd have to change 30 75 round drum magazines after
each pass has not been recorded. Rest assured that it would have been
short, to teh point, disapproving, and contained a lock of words that
rhymed with "Duck".)

In the 1930s, the French built a large gunship with a downward firing
105mm Howitzer. From the 1960s on, the USAF, and several allied
nations, have flown various transports (C-47, C-119, C-130) with
arrays of guns pointing out of the side, aimed by maintaining a pylon
turn around the target. (Well, at first, at least) These guns have
range from 7.62mm machine guns to 105mm Howitzers, backed up by an
extensive sensor suite and ballistic computers. The side-firing bit
allows you to engange targets without flying over them, which is
generally considered a good thing.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster

[KenB]

In article >, Hobo > wrote:
>
>Has there ever been an aircraft with a gun permanently aligned
>off-center? I don't mean swivel mounted, but permanently fixed at a
>point other than straight ahead.

Any Luftwaffe aircraft mounting "Schrage Musik" comes to mind.

Ken
>
>Wouldn't a gun pointed at a downward angle make ground attack easier?

[Yann Delcan]

The germans used the 'shrage musik' cannons to fire upwards (around 45°) for
night fighter use.
The japanese also often used this system on modified J2M3, Ki-45 and J1N1-S.
I also heard about 'shadow detection' upward firing experimental guns on
Fw190, perhaps other types (Bf110).

> Has there ever been an aircraft with a gun permanently aligned
> off-center? I don't mean swivel mounted, but permanently fixed at a
> point other than straight ahead.
>
> Wouldn't a gun pointed at a downward angle make ground attack easier?

[phil hunt]

On Sun, 07 Dec 2003 11:01:20 -0800, Hobo > wrote:
>
>Has there ever been an aircraft with a gun permanently aligned
>off-center? I don't mean swivel mounted, but permanently fixed at a
>point other than straight ahead.

During WW2, many German night fighters were fitted with a gun firing
upwards, to attack bombers.

--
"It's easier to find people online who openly support the KKK than
people who openly support the RIAA" -- comment on Wikipedia
(Email: >, but first subtract 275 and reverse
the last two letters).

[Juvat]

After an exhausting session with Victoria's Secret Police, Hobo
blurted out:

>Has there ever been an aircraft with a gun permanently aligned
>off-center?

F-15's gun is angled slightly above the waterline...for air-to-air,
making it unsuitable for strafe.

At least that's the answer I got at a PACAF conference when I asked
why they didn't have a 51-50 requirement to strafe.

Juvat

[Michael Williamson]

Hobo wrote:

>
> Wouldn't a gun pointed at a downward angle make ground attack easier?

Most likely not, as you wouldn't be able to see what you were
shooting at.

Mike

[Bob Martin]

> Check out the Junkers-Larson ground attack prototype made for the
> U.S. Army in the 1920s. It was basically an all-metal Junkers
> monoplane transport with something like 30 .45 Calibre Thomson
> Submachineguns firing at vatious angle through the bottom fuselage.
> The idea was that it would fly along trench lines at low altitude,
> saturating the trenches with bullets. (The opinions of the Gun
> Plumber on board who'd have to change 30 75 round drum magazines after
> each pass has not been recorded. Rest assured that it would have been
> short, to teh point, disapproving, and contained a lock of words that
> rhymed with "Duck".)

I could have sworn I saw something on the history channel once about a
modification someone tried on a Canberra... they made a pallet for the bomb
bay and fitted a dozen or so guns pointing straight out the bottom of it...
I think they showed it firing in ground tests, but that's all I've ever
heard about it...

[R Haskin]

"Juvat" > wrote in message
...

> F-15's gun is angled slightly above the waterline...for air-to-air,
> making it unsuitable for strafe.
>
> At least that's the answer I got at a PACAF conference when I asked
> why they didn't have a 51-50 requirement to strafe.

Unsuitable is certainly not the word for it. The F-15E community has not
traditionally strafed on a regular basis because of the upcanted gun -- a
10-degree low angle strafe puts you pretty close to the dirt by the time you
cease fire.

Because of the "demand" for bullets in Allied Force, Enduring Freedom, and
Iraqi Freedom, strafe is back in the F-15E vernacular bigtime.

[RobbelothE]

>Check out the Junkers-Larson ground attack prototype made for the
>U.S. Army in the 1920s. It was basically an all-metal Junkers
>monoplane transport with something like 30 .45 Calibre Thomson
>Submachineguns firing at vatious angle through the bottom fuselage.
>The idea was that it would fly along trench lines at low altitude,
>saturating the trenches with bullets. (The opinions of the Gun
>Plumber on board who'd have to change 30 75 round drum magazines after
>each pass has not been recorded. Rest assured that it would have been
>short, to teh point, disapproving, and contained a lock of words that
>rhymed with "Duck".)
>
>In the 1930s, the French built a large gunship with a downward firing
>105mm Howitzer. From the 1960s on, the USAF, and several allied
>nations, have flown various transports (C-47, C-119, C-130) with
>arrays of guns pointing out of the side, aimed by maintaining a pylon
>turn around the target. (Well, at first, at least) These guns have
>range from 7.62mm machine guns to 105mm Howitzers, backed up by an
>extensive sensor suite and ballistic computers. The side-firing bit
>allows you to engange targets without flying over them, which is
>generally considered a good thing.
>
>--

Acutally, I believe the Germans were first. They developed a class of
Riesenflugzeug (Giant Aircraft) which began appearing in 1915. By 1916, LT
Ernst Neuber began working on his idea of mounting a 130mm cannon vertically in
the belly of an R-plane. Static tests began 25 May 1916 using a Gotha East
Experimental. On 6 October 1916 the gun was installed on the R-plane and the
gun was test fired several time in flight on 19 October. The Germans continued
testing and were working on a 105mm automatic cannon firing 20 rounds/minute
when the war ended. Neuber even patented his invention (#305,039).

There are reports of a side-firing .30 calibre machine gun being used on a DH-4
in 1927.

The French system of 1932 used the fameous French 75 mounted side-ways in the
Bordelaise A.B. 22 aircraft.

The USA tested the side-firing gunship concept duirng the summer of 1964 at
Eglin AFB using a C-131 transport and, IIRC, a single .7.62 mini-gun. The first
American gunship was the "FC-47" which carried 10 .30 cal side-firing machine
guns developed by Major Ronald W. Terry at Eglin AFB.


Ed
"The French couldn't hate us any
more unless we helped 'em out in another war."
--Will Rogers



(Delete text after dot com for e-mail reply.)

[Guy Alcala]

R Haskin wrote:

> "Juvat" > wrote in message
> ...
>
> > F-15's gun is angled slightly above the waterline...for air-to-air,
> > making it unsuitable for strafe.
> >
> > At least that's the answer I got at a PACAF conference when I asked
> > why they didn't have a 51-50 requirement to strafe.
>
> Unsuitable is certainly not the word for it. The F-15E community has not
> traditionally strafed on a regular basis because of the upcanted gun -- a
> 10-degree low angle strafe puts you pretty close to the dirt by the time you
> cease fire.
>
> Because of the "demand" for bullets in Allied Force, Enduring Freedom, and
> Iraqi Freedom, strafe is back in the F-15E vernacular bigtime.

An acquaintance who flew A-7s and F-16s has said that the former's M61A1 was
aligned a couple of degrees below the waterline to improve its A/G usefulness,
while the Viper's is mounted slightly above to improve A/A ditto. I don't know
how the F-18 is set up. Marine pilots definitely did a lot of low-angle strafe
in DS.

Guy

[Cub Driver]

>
>Has there ever been an aircraft with a gun permanently aligned
>off-center? I don't mean swivel mounted, but permanently fixed at a
>point other than straight ahead.

Yes. The Japanese Army Air Force regularly mounted oblique cannon
(aimed upward and forward at perhaps a 30-degree angle) in their
interceptors in an attempt (not terribly successful) to shoot down the
B-29s which they couldn't otherwise reach.

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[John Mullen]

RobbelothE wrote:

>>Check out the Junkers-Larson ground attack prototype made for the
>>U.S. Army in the 1920s. It was basically an all-metal Junkers
>>monoplane transport with something like 30 .45 Calibre Thomson
>>Submachineguns firing at vatious angle through the bottom fuselage.
>>The idea was that it would fly along trench lines at low altitude,
>>saturating the trenches with bullets. (The opinions of the Gun
>>Plumber on board who'd have to change 30 75 round drum magazines after
>>each pass has not been recorded. Rest assured that it would have been
>>short, to teh point, disapproving, and contained a lock of words that
>>rhymed with "Duck".)
>>
>>In the 1930s, the French built a large gunship with a downward firing
>>105mm Howitzer. From the 1960s on, the USAF, and several allied
>>nations, have flown various transports (C-47, C-119, C-130) with
>>arrays of guns pointing out of the side, aimed by maintaining a pylon
>>turn around the target. (Well, at first, at least) These guns have
>>range from 7.62mm machine guns to 105mm Howitzers, backed up by an
>>extensive sensor suite and ballistic computers. The side-firing bit
>>allows you to engange targets without flying over them, which is
>>generally considered a good thing.
>>
>>--
>
>
> Acutally, I believe the Germans were first. They developed a class of
> Riesenflugzeug (Giant Aircraft) which began appearing in 1915. By 1916, LT
> Ernst Neuber began working on his idea of mounting a 130mm cannon vertically in
> the belly of an R-plane. Static tests began 25 May 1916 using a Gotha East
> Experimental. On 6 October 1916 the gun was installed on the R-plane and the
> gun was test fired several time in flight on 19 October. The Germans continued
> testing and were working on a 105mm automatic cannon firing 20 rounds/minute
> when the war ended. Neuber even patented his invention (#305,039).
>
> There are reports of a side-firing .30 calibre machine gun being used on a DH-4
> in 1927.
>
> The French system of 1932 used the fameous French 75 mounted side-ways in the
> Bordelaise A.B. 22 aircraft.
>
> The USA tested the side-firing gunship concept duirng the summer of 1964 at
> Eglin AFB using a C-131 transport and, IIRC, a single .7.62 mini-gun. The first
> American gunship was the "FC-47" which carried 10 .30 cal side-firing machine
> guns developed by Major Ronald W. Terry at Eglin AFB.

There was an installation in (I think) the Me-163 Komet which would
trigger an upward-firing weapon when the shadow of an Allied bomber
passed over it. AFAIK was used as well.

John

[Chad Irby]

In article >,
"R Haskin" > wrote:

> "Juvat" > wrote in message
> ...
>
> > F-15's gun is angled slightly above the waterline...for air-to-air,
> > making it unsuitable for strafe.
> >
> > At least that's the answer I got at a PACAF conference when I asked
> > why they didn't have a 51-50 requirement to strafe.
>
> Unsuitable is certainly not the word for it. The F-15E community has not
> traditionally strafed on a regular basis because of the upcanted gun -- a
> 10-degree low angle strafe puts you pretty close to the dirt by the time you
> cease fire.

It's simple.

Just do your strafing runs inverted.

;-)

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

[Keith Willshaw]

"Hobo" > wrote in message
...
>
> Has there ever been an aircraft with a gun permanently aligned
> off-center? I don't mean swivel mounted, but permanently fixed at a
> point other than straight ahead.
>

Yes

> Wouldn't a gun pointed at a downward angle make ground attack easier?

Possibly but the most obvious examples had the guns pointed UP
at around 30 degrees. German nightfighters in WW2 would position
themselves below and behind their target and fire at bombers
silouhetted against the dark sky.

Keith

[Yeff]

On Sun, 07 Dec 2003 22:31:58 GMT, Guy Alcala wrote:

> I don't know how the F-18 is set up.

The F-15 is set up to "loft" the bullets (loft is the word I remember
reading, I just can't remember where I read it...) so I'd think MD did the
same with the Hornet.

-Jeff B. (with yet another cite-free post)
yeff at erols dot com

[Juvat]

After an exhausting session with Victoria's Secret Police "R Haskin"
blurted out:

>Unsuitable is certainly not the word for it. The F-15E community has not
>traditionally strafed on a regular basis because of the upcanted gun -- a
>10-degree low angle strafe puts you pretty close to the dirt by the time you
>cease fire.

Well what would I know? I was a Viper guy.

I talked with Albino guys from Kadena that were experimenting with
surface attack...no strafe. When asked they said something like, "Are
you ****ing kidding? The gun points up, we'd have to bury the nose to
strafe."

They indicated that it was NOT suitable.

>Because of the "demand" for bullets in Allied Force, Enduring Freedom, and
>Iraqi Freedom, strafe is back in the F-15E vernacular bigtime.

Cool...

[John Carrier]

The F-14 was tilted up about 3 degrees IIRC. Allowed you to track with less
lead and closure and perhaps less likelihood of hitting the target.

R / John

"Hobo" > wrote in message
...
>
> Has there ever been an aircraft with a gun permanently aligned
> off-center? I don't mean swivel mounted, but permanently fixed at a
> point other than straight ahead.
>
> Wouldn't a gun pointed at a downward angle make ground attack easier?

[WaltBJ]

Curtiss F-type flying boats in WW1 had a Davis recoiless gun mounted
in the nose cockpit. It had to be fired downward because its recoil
counterweight was a charge of shot in a grease matrix fired out the
back end of the tube.
FWIW I understand the initial idea for the 'Puff' series gunships was
the technique of servicing missionary stations in the Amazon with
Piper Super Cubs by flying in a tight circle while lowering a bucket
on a rope. Due to aero drag on the rope the bucket lagged behind and
pivoted on the polar axis of the circle and the ground people could
remove their mail, etc, and place their outgoing mail and requests in
the bucket which was then hauled back up. The rotation was slow enough
to be no problem, and then the curvature of the rope reminded someone
of the trajectory of a gun so - voila!
As for strafing in the F15 with its upward gun - check the -34 for the
sight mil settings and fire further out so the bullets will drop down
below the extended water line. Time of flight will indicate how far
the bullets will drop - it is all solvable with simple trig.
Walt BJ

[Guy Alcala]

Yeff wrote:

> On Sun, 07 Dec 2003 22:31:58 GMT, Guy Alcala wrote:
>
> > I don't know how the F-18 is set up.
>
> The F-15 is set up to "loft" the bullets (loft is the word I remember
> reading, I just can't remember where I read it...) so I'd think MD did the
> same with the Hornet.

That doesn't necessarily follow. Different missions, different services. The
F-15 was slanted A/A from the beginning, while the F-18 was originally two
variants, one fighter and one attack, which were later merged. I don't know
which was given priority as far as the gun alignment goes, or whether they
just left it in the middle. But if we ask on r.a.m.n., someone would probably
know.

Guy

[B2431]

>From: (WaltBJ)

>FWIW I understand the initial idea for the 'Puff' series gunships was
>the technique of servicing missionary stations in the Amazon with
>Piper Super Cubs by flying in a tight circle while lowering a bucket
>on a rope. Due to aero drag on the rope the bucket lagged behind and
>pivoted on the polar axis of the circle and the ground people could
>remove their mail, etc, and place their outgoing mail and requests in
>the bucket which was then hauled back up. The rotation was slow enough
>to be no problem, and then the curvature of the rope reminded someone
>of the trajectory of a gun so - voila!

There was a photograph in National Geographic where a man in the Amazon is
reaching up towards a can. He had either just released it or was reaching for
it. The aircraft that had lowered it was off in the distance in the same
photograph.

The particular article was printed in the mid 1960s. 1967 or so if memory
serves.

It amazes me I can't remember 24 hours ago yet I can remember 35 years ago.

Dan, U. S. Air Force, retired

[John Keeney]

"Hobo" > wrote in message
...
>
> Has there ever been an aircraft with a gun permanently aligned
> off-center?

Yes, several going as far back at least as far as WWI.
I'm afraid I'm brain locking on the designations though. In
Vietnam B-57 had gun packs fitted that shot down at a very
sharp angle- may even have been vertical- for night straffing
the trail.

>I don't mean swivel mounted, but permanently fixed at a
> point other than straight ahead.
>
> Wouldn't a gun pointed at a downward angle make ground attack easier?

I don't know why the idea keeps failing to catch on; it could
be it's too single purpose for fighters or just not as easy to
aim.

[Cub Driver]

This is wonderful. Can either of you or anybody point me to more
information about this service?

I realize there are only 12 issues of Geographic a year, but it would
help if I could narrow it down.

On 08 Dec 2003 06:06:09 GMT, (B2431) wrote:

>>FWIW I understand the initial idea for the 'Puff' series gunships was
>>the technique of servicing missionary stations in the Amazon with
>>Piper Super Cubs by flying in a tight circle while lowering a bucket
>>on a rope. Due to aero drag on the rope the bucket lagged behind and
>>pivoted on the polar axis of the circle and the ground people could
>>remove their mail, etc, and place their outgoing mail and requests in
>>the bucket which was then hauled back up. The rotation was slow enough
>>to be no problem, and then the curvature of the rope reminded someone
>>of the trajectory of a gun so - voila!
>
>There was a photograph in National Geographic where a man in the Amazon is
>reaching up towards a can. He had either just released it or was reaching for
>it. The aircraft that had lowered it was off in the distance in the same
>photograph.
>
>The particular article was printed in the mid 1960s. 1967 or so if memory
>serves.

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[Bob Martin]

> I don't know why the idea keeps failing to catch on; it could
> be it's too single purpose for fighters or just not as easy to
> aim.


I think the A-10's gun might be downward pointed a bit... but most fighters
wouldn't use a downward-pointing one because it is unsuitable for a-a work.

[John Hairell]

On Mon, 08 Dec 2003 05:07:41 -0500, Cub Driver
> wrote:

>
>This is wonderful. Can either of you or anybody point me to more
>information about this service?
>
>I realize there are only 12 issues of Geographic a year, but it would
>help if I could narrow it down.
>

I remember the same photo and I'm pretty sure it's a mid-'60s issue,
probably from 1965-1967.

The photo shows somebody either putting mail in or pulling mail out of
a bucket hanging on a rope, and you can see the aircraft that's
dropping the bucket flying at altitude in the background.

I did a lookup on NGS' pubs website at
http://www.nationalgeographic.com/publications/explore.html
and got some possibilities:

keyword "Amazon" - Oct 1972 "Amazon--The River Sea"
Aug 1970 - "Colombia, from Amazon to Spanish
Main"
May 1964 - "Indians of the Amazon Darkness"
March 1959 - "Children of the Sun and Moon"
keyword "Colombia" May 1966 "Capturing Strange Creatures in Colombia"
Aug 1970 "Colombia, from Amazon to Spanish Main"
Feb 1966 "Flamboyant Is the Word for Bolivia"

There are many possibilities - try different keywords for various SA
countries and narrow down the results by date.

John Hairell )

[Jeb Hoge]

"Bob Martin" > wrote in message >...
> > I don't know why the idea keeps failing to catch on; it could
> > be it's too single purpose for fighters or just not as easy to
> > aim.
>
>
> I think the A-10's gun might be downward pointed a bit... but most fighters
> wouldn't use a downward-pointing one because it is unsuitable for a-a work.

The Hog's overall assembly is not on the jet's centerline, but it's
arranged so that the firing barrel is centered up, probably perfectly
squared, when it fires. Given the power of that particular weapon,
I'd be a little surprised if the firing barrel was anything BUT
perfectly square to the centerline (both X and Y axis). Of course, I
also seem to recall that the shell basically traces a straight line
from barrel to "effective range", and doesn't need drop factored in.

[Cub Driver]

Thanks, I'll look for it.

On Mon, 08 Dec 2003 11:35:02 -0500, John Hairell >
wrote:

>I remember the same photo and I'm pretty sure it's a mid-'60s issue,
>probably from 1965-1967.
>
>The photo shows somebody either putting mail in or pulling mail out of
>a bucket hanging on a rope, and you can see the aircraft that's
>dropping the bucket flying at altitude in the background.
>
>I did a lookup on NGS' pubs website at
>http://www.nationalgeographic.com/publications/explore.html
>and got some possibilities:
>
>keyword "Amazon" - Oct 1972 "Amazon--The River Sea"
> Aug 1970 - "Colombia, from Amazon to Spanish
>Main"
> May 1964 - "Indians of the Amazon Darkness"
> March 1959 - "Children of the Sun and Moon"
>keyword "Colombia" May 1966 "Capturing Strange Creatures in Colombia"
> Aug 1970 "Colombia, from Amazon to Spanish Main"
> Feb 1966 "Flamboyant Is the Word for Bolivia"
>
>There are many possibilities - try different keywords for various SA
>countries and narrow down the results by date.

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[OXMORON1]

The mail/supplies in the bucket trick goes back farther than that. IIRC the
"bucket trick" was the inspiration for the AC-47 development for holding the
fire on the target in a steep banked turn.

In addition to the Amazon, the technique was used by missionaries in Borneo,
both sometime in the late twenties or early thirties.

Oxmoron1
Don't ask me where I read it,but it was a long time ago.

[[email protected]]

(Jeb Hoge) wrote:

> Of course, I
>also seem to recall that the shell basically traces a straight line
>from barrel to "effective range", and doesn't need drop factored in.

Eh?... surely you're not saying that the rounds don't drop in
flight?...I hope?...
--

-Gord.

[Bob Martin]

> > Of course, I
> >also seem to recall that the shell basically traces a straight line
> >from barrel to "effective range", and doesn't need drop factored in.
>
> Eh?... surely you're not saying that the rounds don't drop in
> flight?...I hope?...


Well, I know the firing barrel is centered laterally, but I think the gun
itself may be angled down a couple degrees (though still passing through the
center of gravity of the aircraft, so as to not produce any pitching
moment), though probably not more than 2 or 3. This would help with gun
tracking and make strafing runs a little safer.

As far as the "straight line" from the barrel... the muzzle velocity of the
GAU-8/A is such that, although the bullets do drop in flight (to not do so
would either imply lift being generated, or laws of physics being violated),
the drop is considered negligible, and therefore the gunsight is a simple
fixed reticle in the HUD.

For example... at 4000 feet, the bullets will only drop about 10
feet--random dispersion will be greater than that.

[[email protected]]

"Bob Martin" > wrote:

>> > Of course, I
>> >also seem to recall that the shell basically traces a straight line
>> >from barrel to "effective range", and doesn't need drop factored in.
>>
>> Eh?... surely you're not saying that the rounds don't drop in
>> flight?...I hope?...
>
>
>Well, I know the firing barrel is centered laterally, but I think the gun
>itself may be angled down a couple degrees (though still passing through the
>center of gravity of the aircraft, so as to not produce any pitching
>moment), though probably not more than 2 or 3. This would help with gun
>tracking and make strafing runs a little safer.
>
>As far as the "straight line" from the barrel... the muzzle velocity of the
>GAU-8/A is such that, although the bullets do drop in flight (to not do so
>would either imply lift being generated, or laws of physics being violated),
>the drop is considered negligible, and therefore the gunsight is a simple
>fixed reticle in the HUD.
>
>For example... at 4000 feet, the bullets will only drop about 10
>feet--random dispersion will be greater than that.
>

But that puts the centre of the dispersion pattern ~ten feet
below the aim point at that range doesn't it?
--

-Gord.

[Tarver Engineering]

"B2431" > wrote in message
...

> It amazes me I can't remember 24 hours ago yet I can remember 35 years
ago.

Yet the rest of us are amazed when you make up things from 35 years ago,
Dan.

[Bob Martin]

> >For example... at 4000 feet, the bullets will only drop about 10
> >feet--random dispersion will be greater than that.
> >
>
> But that puts the centre of the dispersion pattern ~ten feet
> below the aim point at that range doesn't it?

Yeah, but that's only about a sixth of a degree of arc...

also, a tank is what, 6-8 feet tall at least? Ten feet at that range is
very little to be concerned about... anyways, the point being that gravity
drop is less of a factor with the GAU-8 than with other guns.

[Mike Marron]

> (OXMORON1) wrote:

>The mail/supplies in the bucket trick goes back farther than that. IIRC the
>"bucket trick" was the inspiration for the AC-47 development for holding the
>fire on the target in a steep banked turn.

>In addition to the Amazon, the technique was used by missionaries in Borneo,
>both sometime in the late twenties or early thirties.

>Oxmoron1
>Don't ask me where I read it,but it was a long time ago.

As the legend goes, the missionaries discovered that by squaring
their groundspeed and dividing that figure by 15, they would arrive at
the proper "pivotal altitude" from which to fly circles allowing them
to lower a bucket of medicine and supplies to people on the ground.
Nowadays the maneuver is called Eights On Pylons.

[John Keeney]

"Cub Driver" > wrote in message
...
>
> This is wonderful. Can either of you or anybody point me to more
> information about this service?
>
> I realize there are only 12 issues of Geographic a year, but it would
> help if I could narrow it down.

I've read about the same technique being used in Oz for back country
mail.

[B2431]

>From: "Tarver Engineering"
>Date: 12/8/2003 7:31 PM Central Standard Time
>Message-id: >
>
>
>"B2431" > wrote in message
...
>
>> It amazes me I can't remember 24 hours ago yet I can remember 35 years
>ago.
>
>Yet the rest of us are amazed when you make up things from 35 years ago,
>Dan.
>
Tarver, I cited my source which is something you have never done.

Until you have something constructive to say go chew on a bowlful of rusty
double edged razorblades at let us grownups talk.

Dan, U. S. Air Force, retired

[John Hairell]

On 08 Dec 2003 23:23:12 GMT, (OXMORON1) wrote:

>The mail/supplies in the bucket trick goes back farther than that. IIRC the
>"bucket trick" was the inspiration for the AC-47 development for holding the
>fire on the target in a steep banked turn.
>
>In addition to the Amazon, the technique was used by missionaries in Borneo,
>both sometime in the late twenties or early thirties.
>

There's at least one on-line ref to a basket of eggs being delivered
this way in 1939, so it was probably done quite a few years before
that. I would think the technique grew out of all of the multiple
experimentations in the 1920s for dropping off air mail without
landing.

John Hairell )

[Jeb Hoge]

"Bob Martin" > wrote in message >...
> > >For example... at 4000 feet, the bullets will only drop about 10
> > >feet--random dispersion will be greater than that.
> > >
> >
> > But that puts the centre of the dispersion pattern ~ten feet
> > below the aim point at that range doesn't it?
>
> Yeah, but that's only about a sixth of a degree of arc...
>
> also, a tank is what, 6-8 feet tall at least? Ten feet at that range is
> very little to be concerned about... anyways, the point being that gravity
> drop is less of a factor with the GAU-8 than with other guns.

Right, that was basically it. Operationally speaking, at ranges where
the A-10 intiates/presses an attack, the GAU-8 fires a straight shot.
I also remember a graphic detailing muzzle velocity of the 23mm round
from the ZSU versus from a GAU-8, and it showed that if a Hog and a
ZSU fired accurate rounds at each other at the same exact time, the
ZSU died first and the Hog could (conceivably) jink before the 23mm
arrived. Pretty neat stuff, if somewhat idealized.

[[email protected]]

"Bob Martin" > wrote:

>> >For example... at 4000 feet, the bullets will only drop about 10
>> >feet--random dispersion will be greater than that.
>> >
>>
>> But that puts the centre of the dispersion pattern ~ten feet
>> below the aim point at that range doesn't it?
>
>Yeah, but that's only about a sixth of a degree of arc...
>
>also, a tank is what, 6-8 feet tall at least? Ten feet at that range is
>very little to be concerned about... anyways, the point being that gravity
>drop is less of a factor with the GAU-8 than with other guns.
>

I see...that's interesting...how do they do that? (your last
sentence I mean)

-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"

[Bob Martin]

Gord Beaman > wrote in message
...
> "Bob Martin" > wrote:
>
> >> >For example... at 4000 feet, the bullets will only drop about 10
> >> >feet--random dispersion will be greater than that.
> >> >
> >>
> >> But that puts the centre of the dispersion pattern ~ten feet
> >> below the aim point at that range doesn't it?
> >
> >Yeah, but that's only about a sixth of a degree of arc...
> >
> >also, a tank is what, 6-8 feet tall at least? Ten feet at that range is
> >very little to be concerned about... anyways, the point being that
gravity
> >drop is less of a factor with the GAU-8 than with other guns.
> >
>
> I see...that's interesting...how do they do that? (your last
> sentence I mean)

That's what I've been trying to explain... the bullets from the GAU-8 go
faster and therefore drop less for a given range than do bullets from other
guns. The smaller the drop, the easier it is to compensate for. In the
case of the A-10, the drop is so small that, for practical purposes, the
bullets go in a straight line.

[Tony Williams]

"Gord Beaman" ) wrote in message >...
> "Bob Martin" > wrote:
>
> >> >For example... at 4000 feet, the bullets will only drop about 10
> >> >feet--random dispersion will be greater than that.
> >> >
> >>
> >> But that puts the centre of the dispersion pattern ~ten feet
> >> below the aim point at that range doesn't it?
> >
> >Yeah, but that's only about a sixth of a degree of arc...
> >
> >also, a tank is what, 6-8 feet tall at least? Ten feet at that range is
> >very little to be concerned about... anyways, the point being that gravity
> >drop is less of a factor with the GAU-8 than with other guns.
> >
>
> I see...that's interesting...how do they do that? (your last
> sentence I mean)

The GAU-8/A projectiles have a much better ballistic coefficient than
most aircraft gun shells because they are particularly heavy and
well-shaped, so they slow down less and arrive at the target more
quickly - so gravity has less time to act on them. They are not magic,
however, and will drop by the same amount as any other shell in the
same time.

By comparison with ground-based AA guns, the A-10's weapon also
benefits from the forward speed of the aircraft, and the fact that it
is firing 'downhill', which gives it a couple of built-in advantages.
However, if the AA gun is firing FAPDS that would restore the balance,
as an aircraft can't use this ammo.

BTW, the current Russian 30mm shells are almost as good as the
GAU-8/A's.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/

[DBurch7672]

During WW2, many German night fighters were fitted with a gun firing upwards,
to attack bombers.

Actually: 1. It could be one or *multiple* guns
2. They were at an oblique angle
3. It came about when some genius in the
Luftwaffe realized that RAF
bombers had *no* belly defenses;
[GEE! IF Churchill had asked NICELY; we COULD
have sold
him some B-17/24 type BALL
TURRETS OR THE PLANS
FOR SAME! :)]

4. the Germans called then
"Schrage" (sic, needs unlauts!)
Musik" or "Jazz Music" in
German!

[Krztalizer]

>
> 4. the Germans called then
>"Schrage" (sic, needs unlauts!)
> Musik" or "Jazz Music" in
>
>German!

Umlauts-R-Us

ü Alt 129
ä 132
ß 225
ö 148
Ä 142
Ö 153
Ü 154

[Keith Willshaw]

"DBurch7672" > wrote in message
...
> During WW2, many German night fighters were fitted with a gun firing
upwards,
> to attack bombers.
>
> Actually: 1. It could be one or *multiple* guns
> 2. They were at an oblique angle
> 3. It came about when some genius in
the
> Luftwaffe realized that RAF
> bombers had *no* belly defenses;

Not strictly accurate , some Lancasters had ventral guns, the
problem was that the space was needed for the H2S radar
installation



> [GEE! IF Churchill had asked NICELY; we
COULD
> have sold
> him some B-17/24 type BALL
> TURRETS OR THE PLANS
> FOR SAME! :)]
>

Given that the RAF had a number of B-17's complete
with ball turrets I rather think the idea was not completely
unknown.

Keith

[Yama]

"Keith Willshaw" > wrote in message
...
> Given that the RAF had a number of B-17's complete
> with ball turrets I rather think the idea was not completely
> unknown.

Would it really have helped anyway? AIUI ventral ball turrets were very
uncomfortable and in day bombers, gunners moved to them only when fighters
were detected. Besides ventral gunner is still in enormous disadvantage
against a night fighter, he doesn't have a radar and night fighter can see
the bomber easier against the sky.

[[email protected]]

(Krztalizer) wrote:

>>
>> 4. the Germans called then
>>"Schrage" (sic, needs unlauts!)
>> Musik" or "Jazz Music" in
>>
>>German!
>
>Umlauts-R-Us
>
>ü Alt 129
>ä 132
>ß 225
>ö 148
>Ä 142
>Ö 153
>Ü 154
>

Thanks Gordon Ü
--

-Gord.

[Les Matheson]

Why yes, the AC-47, AC-119, and the AC-130A/E/H/U, to name a few.
--
Les
F-4C(WW),D,E,G(WW)/AC-130A/MC-130E EWO (ret)

[Peter Stickney]

In article >,
"Yama" > writes:
>
> "Keith Willshaw" > wrote in message
> ...
>> Given that the RAF had a number of B-17's complete
>> with ball turrets I rather think the idea was not completely
>> unknown.
>
> Would it really have helped anyway? AIUI ventral ball turrets were very
> uncomfortable and in day bombers, gunners moved to them only when fighters
> were detected. Besides ventral gunner is still in enormous disadvantage
> against a night fighter, he doesn't have a radar and night fighter can see
> the bomber easier against the sky.

Considering that climbing into, or out of, a ball turret wasn't a
trivial task, and that doing so at 25,000' would require handling
latches & controls that have cold-soaked at -40 (F or C, it doesn't
matter, much) for several hours, not to mention that you'd have to be
juggling Oxygen, connunication, and suit heater power leads, (Oh,
yeah, and you can't climb into the turret with it in the trail
position, you've got to hand crank it so that the guns are pretty much
straight down, then climb in), I'd rather doubt it.
Oh, yeah, the cold temperatures would freeze up the traverse &
elevation gear if it weren't energized & exercized.

You weren't supposed to be in the turret for takeoff or landing, but
the gunner would enter the turret sometime before passing through
10,000' on the climbout.

Now, those "dustbin" things that the Germans & Japanese were so fond
of - those strike me as a bit, well, optimistic.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster

[Tony Williams]

"Yama" > wrote in message >...
> "Keith Willshaw" > wrote in message
> ...
> > Given that the RAF had a number of B-17's complete
> > with ball turrets I rather think the idea was not completely
> > unknown.
>
> Would it really have helped anyway? AIUI ventral ball turrets were very
> uncomfortable and in day bombers, gunners moved to them only when fighters
> were detected. Besides ventral gunner is still in enormous disadvantage
> against a night fighter, he doesn't have a radar and night fighter can see
> the bomber easier against the sky.

Quite so. The idea of upward-firing guns for use against bombers
originated in WW1 (mainly to attack airships) and there were British
experiments with upward-firing cannon interwar. Although the
difficulty in defending this area was probably a factor in the German
use of Schräge Musik, I think that more important issues were:

1. The bombers were generally much easier to spot from below.

2. The fighters were harder to spot from above.

3. The fighters had a nice, big, steady target to aim at in the
bomber's planform, instead of aiming at a much smaller end-on target
while being bounced around in the slipstream.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Military gun and ammunition discussion forum:
http://forums.delphiforums.com/autogun/messages/

[Cub Driver]

>During WW2, many German night fighters were fitted with a gun firing upwards,
>to attack bombers.

Likewise in Japan (day fighters also).

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[Cub Driver]

4. In the case of the Japanese, they had trouble get up to the B-29's
altitude.

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[Keith Willshaw]

"Yama" > wrote in message
...
>
> "Keith Willshaw" > wrote in message
> ...
> > Given that the RAF had a number of B-17's complete
> > with ball turrets I rather think the idea was not completely
> > unknown.
>
> Would it really have helped anyway? AIUI ventral ball turrets were very
> uncomfortable and in day bombers, gunners moved to them only when fighters
> were detected. Besides ventral gunner is still in enormous disadvantage
> against a night fighter, he doesn't have a radar and night fighter can see
> the bomber easier against the sky.
>
>

Probably not which is why a replacement wasnt pursued.

Keith

[Cub Driver]

>-40 (F or C, it doesn't
>matter, much)

Doesn't matter at all, to judge by my thermometer. They appear to be
equal.

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[WaltBJ]

I have read that the Canadian squadrons with Halifaxes had a ventral
mounting - not a turret - where a gunner had a good chance of spotting
and shooting at a LW night fighter moving in under him. I also
remember the source cited the RCAF had a much greater survival rate in
their Halifaxes than did the RAF for that very reason. Sorry - I can't
remember the source but believe it was a semi-offical history of the
RAF bombing campaign.
Walt BJ

[WaltBJ]

As for strafing with an upward pointing gun - I was surprised to
discover that the USAF had forgotten all about high-angle strafe. I
was taught the technique at Nellis back in 1954. 60 degree dive angle
- designed to negate the advantage of a foxhole. At Da Nang I worked
up my own sight settings for 45 and 60 degrees and used the gun in 45
degree dive bomb passes to keep the flak gunners busy. With a little
work and a -34 one can derive a sight setting that works for both gun
and bomb (different release altitudes, though). Some conditions used
12 o'clock on the F4's 50 mil reticle for the gun and 6 o'clock or the
pipper itself for bombing. Amazing what a guy will do when bored . . .
but hell, they worked just fine.
Walt BJ

[John Boyle]

WaltBJ wrote:
> As for strafing with an upward pointing gun - I was surprised to
> discover that the USAF had forgotten all about high-angle strafe. I
> was taught the technique at Nellis back in 1954. 60 degree dive angle
> - designed to negate the advantage of a foxhole. At Da Nang I worked
> up my own sight settings for 45 and 60 degrees and used the gun in 45
> degree dive bomb passes to keep the flak gunners busy. With a little
> work and a -34 one can derive a sight setting that works for both gun
> and bomb (different release altitudes, though). Some conditions used
> 12 o'clock on the F4's 50 mil reticle for the gun and 6 o'clock or the
> pipper itself for bombing. Amazing what a guy will do when bored . . .
> but hell, they worked just fine.
> Walt BJ
To Cub Driver, Walt BJ, et al: Does anyone remember the B-25J with a 75
millimeter cannon firing off center, used in the Pacific theater?

[Tony Williams]

John Boyle > wrote in message >...
> To Cub Driver, Walt BJ, et al: Does anyone remember the B-25J with a 75
> millimeter cannon firing off center, used in the Pacific theater?

Indeed - an interesting beast. The M4 gun was based on the Sherman
tank's 75mm gun, and was still manually loaded. It must have been fun
chucking those big shells in the breech while trying to stay balanced
as the plane made its attack run. I understand that the recoil was
such that by the end of a typical four-shot attack run, the plane was
slowed by about 10 mph.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/

[Alan Dicey]

Emmanuel Gustin wrote:

> There was a 'Preston-Green' ventral gun mount for a .50 in gun,
> which was widespread until the installation of H2S radar
> required its removal. Many units improvised other ventral gun
> mounts. A simple clear-vision panel, with or without gun, was
> a much better solution than the available turrets.

I am reading R. Wallace Clarke's book "British Aircraft Armamant", and
he says that the Preston Green under defence mounting was fitted to all
Halifax Mk III's. Aircraft production was outstripping radar set
production, so it was gun or nothing, not gun or H2S. When H2S
production ramped up, the turrets were replaced by radar scanners.

>
> Some Halifaxes and Lancasters had ventral turrets, but the
> Boulton Paul 'R' and the Frazer-Nash FN.64 were of the
> retractable periscope-sighted kind and therefore rather useless
> even by day. (Coastal Command nevertheless had the FN.64
> turret installed on its Halifaxes.)

Can you say what your source is for this, please? According to Clarke,
HP aircraft never seem to have had FN turrets (save for the Harrow).
Coastal Command made use of the FN77 Leigh Light, a modified FN25 under
turret, in its Wellingtons.

> The 'low-drag' FN.21A
> apparently fitted to some early Manchesters and Lancasters
> was a retractable dustbin turret with extending 'shoes' to
> accomodate the feet and legs of the gunner, which must have
> resulted in a truly enormous amount of drag when lowered.
>

According to Clarke, the FN21a was only fitted to Manchesters. The FN64
(derived from the FN60 fitted to Blenheims) was fitted to early
Lancasters, and refitted to four of 5 Group's squadrons in June 1944 for
daylight raids (replacing the H2S scanner).

Lowering the dustbin under-turret apparantly produced a marked change in
trim, and a gunner described the experience of manning one as like
getting into a refrigerator with the lights out.

All accounts seem to agree that the only successful ventral defence
mounting was the Sperry ball turret.