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Talk:Douglas AC-47 Spooky/Archive 1

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Archive 1

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Removed reference to ".30 in" miniguns. There was never any such beast. In US military usage ".30 in" refers to the "caliber .30, model of 1906" cartridge, better known as the .30-06, the GE miniguns in question were 7.62mm NATO, referred to as "7.62mm" in US usage. —Preceding unsigned comment added by 99.202.228.215 (talk) 13:08, 1 October 2009 (UTC)

Questionable accuracy of area-target saturation claim

It looks to me like there's a few discrepancies in this page. At the top it says that the alternate loadout was with 10 .50 caliber machine guns, but in the specs it says they're .30 caliber. At the top, it also says the guns were controlled by the pilot, but the crew list refers to gunners. 69.40.178.172 18:24, 24 November 2006 (UTC)

Note also, that an AC47 equipped with 3 mini guns could not, in a "three second burst," place a bullet in each square foot of a football field. An American football field measures 160'x360'=57,600 square feet. The mini-guns have a staiblized fire rate of about 18,000 rpm (3x6000). Therefore, a three second burst would be 1/20 of minute or 1/20 of 18,000. This yields only 900 rounds. Furthermore, the mini-guns need a short amount of time to "spool up" to their full cyclical rate.

You'd need about 3 minutes of sustained fire to cover the 57,600 square feet of field. The mini-guns would get pleny hot, the gun gases would probably stall the AC47's engines, and could an AC47 get off the ground carrying that much ammo?

Better start over with this one.

Tsaman 21:56, 6 January 2007 (UTC)

Still dubious

The article now says both:

Coverage given by a Spooky was over an elliptical area approximately 52 yd (47.5 m) in diameter, placing a round every 2.4 yd (2.2 m) during a 3-second burst.

and later:

Now using the call sign "Spooky", each of its three 7.62 mm miniguns could selectively fire either 50 or 100 rounds per second. Cruising in an overhead left-hand orbit at 120 knots air speed at an altitude of 3,000 feet, the gunship could put a high explosive or glowing red incendiary bullet into every square yard of a football field-sized target in three seconds.

First claim: with 3 guns operating at high rate (100 rounds per second each), three seconds of fire in principle amounts to 900 rounds. A circle 52 yd in diameter has an area of 2,124 yd² Dividing that by 900 rounds is 2.36 yd², so we see the calculation performed to support the first claim, which is ball-park reasonable. However it still ignores spool-up time, and also assumes that fire is distributed perfectly evenly across the target, which is extremely unlikely.

Also, we are not given the other dimension of the ellipse; since the aircraft's orbit is symmetric, you might think the beaten zone is close to symmetric too, and whoever has done this calculation seems to have assumed that. However, an C-47 can't possibly turn through more than a tiny fraction of a full orbit in 3 seconds. (To do a full orbit in 3 seconds at 120 kts you would need to pull over 12 g!) A more accurate approximation is to assume that over such a short time period, it is flying an approximate straight line. In that case, we get 52 yd wide x 197 yd long (at 120 kts) which is close to the football field mentioned later. Thus, even the first, more reasonable claim seems to be based on dubious assumptions which in practice exaggerate the density of fire by a factor of least 3.7 times and probably much more. (Of course, the exact density depends on forward airspeed and altitude.)

The second claim is still patent rubbish, even though it has been improved by an order of magnitude by downgrading from square feet to square yards. An American football field is 6,400 yd², so at 900 rounds per second it would take 7.1 seconds to put a round into every square yard. Thus the claim is still more than double what is physically possible -- even ignoring spool-up time, and distribution of fire. It also seems to be using the "football field" as an approximate description of a 53 yd wide dispersion multiplied by the distance of forward travel (approximately linear over such a short time frame.) In that case, a better approximation is 10,000 yd² which makes the claimed density more than triple what is possible.

Even worse is the reference to "high explosive or glowing red incendiary bullet(s)". It seems clear from the text that at this time, the only guns on board the AC-47 were the aforementioned miniguns, which fire 7.62 mm NATO ammunition. There is no such thing as a high explosive 7.62 NATO round, and incendiary rounds in this calibre are extremely unusual (the only ones I have heard of are the spotting rounds for certain RCLs.) This seems to possibly be a confused reference to PGM-38/U 25 mm high explosive / incendiary ammunition used in the current in-service AC-130U, which is also nicknamed "Spooky" but is a completely different aircraft (much larger, and much more recent.)

Therefore I think we should not only remove the dubious saturation claim, but search the article for all instances where AC-130U "Spooky" data has been erroneously used in reference to the AC-47 "Spooky". -- 202.63.39.58 (talk) 05:22, 10 October 2009 (UTC)

You've more than convinced me. Nicely done analysis. --Itsfullofstars (talk) 05:55, 10 October 2009 (UTC)

Why no such gunships in WWII?

GOOD QUESTION; The main reason, is because the electric firing (rotating) gatling gun was not readily available until Vietnam.

I'm curious about why there were no similar gunships in World War II. It seems to me some applications are obvious in hindsight. For example:

  • Anti-shipping. U.S. forces repeatedly attempted high-altitude bombing against enemy ships, and these proved to be ineffective with the dumb bombs of the time. Battle of the Coral Sea#The Battle says: Land-based B-17s attacked the approaching Port Moresby invasion fleet on May 6, with the usual lack of success. Almost another year would pass before the Air Force realized that high-level bombing raids against moving naval targets were pointless.
    • A large ship is roughly the size of a football field (or two). It seems to me that a gunship could probably fly a modified pylon turn around a moving ship, and saturate it with gunfire about as easily as hitting a stationary ground target of similar football-field size. A B-17 gunship could probably have mounted a large-caliber side-firing cannon with sufficient range to allow the orbiting gunship to stay out of easy range of the target's anti-aircraft guns, and fire armor-piercing shells into the target at its leisure. A squadron of B-17 gunships could distribute themselves around the orbit circle, and fire at a ship from all directions simultaneously. Merchant ships and transports would have been easy prey; even battleships might be taken on, especially if the orbiting gunships were to concentrate their fire on the superstructure and knock out the ship's command center.
  • Support of ground troops. During amphibious landings and other ground engagements.

Was the gunship idea considered and rejected during WWII, or was this just a case of nobody on any side of the conflict coming up with the idea at the time? --Teratornis 18:17, 10 February 2007 (UTC)

Actually, certain histories suggest that the medium bomber gunship of the pacific theatre is in fact the forefather of the more modern gunship concept. I don't think there was an airframe at the time that would've provided the stability needed for the type of guns required for anti-shipping duties in the pacific at the time. The A-20, B-25, and B-26 gunships all used massed forward firing armament to suppress anti-aircraft defenses during attack runs, rather than as a method actually doing lethal damage to ships or land targets. Only the Mosquito XVIII and B-25G/H were developed specifically for the anti-shipping requirement (Unlike the majority of the other developments, mainly on the German side for tank busting), with 57mm and 75mm cannon respectively. I'm still not sure a side-firing mount for these weapons and others would've been possible on any of the aircraft of the time. Note that, the AC-47 w/ 10 .30 caliber machine guns is representative of what might've been possible in the WWII timeline, and was quickly deemed totally inferior to the AC-47 with 3 miniguns. For more on the official USAF history I suggest looking online for a pdf copy of "Development and Employment of Fixed-Wing Gunships 1962-1972" by Jack S. Ballard. I know there should be a free copy somewhere, as I have one that I found. I would recommend searching for it through the Virtual Vietnam Archive at Texas Tech University here: http://www.virtualarchive.vietnam.ttu.edu/starweb/vva/servlet.starweb?path=vva/vva.web -- Thatguy96 12:33, 12 March 2007 (UTC)
Well, there's another reason, even if electric Gatling guns had been available. AC-130 and previous AC-47 are extremely vulnerable to effective LLAD fire. They are only used in COIN operations, and even then are only used at night because even massed light automatic fire has a high probability of shooting them down. If you tried this trick on a typical WW2 warship, which fairly bristled with light and medium calibre LLAD gunnery, you would last about a tenth of a second before your airframe disintegrated in a hail of lead (which is largely why, of course, those USAAF bombers preferred high altitude bombing even though it mainly missed.) When strafing was used (against more lightly armed targets), the objective was to fly a high speed trajectory that maximised simultaneous rates of change in target azimuth and elevation, to make gunnery solutions very difficult. Orbiting at constant radius is the exact opposite; the only simpler target solution is for hovering.
Claiming you would use "cannon with sufficient range to allow the orbiting gunship to stay out of easy range of the target's anti-aircraft guns" is plain not going to work, because the maximum effective range of ship-borne AA gunnery is far greater than anything that is practical to mount in an aircraft, by simple virtue of the fact that ships are big. Also, it is unlikely that any gun that could be fitted in a WW2 aircraft would be effective against warship armour of the period; that is why they used bombs. Remember, these ships were built to slug it out with high velocity 5" and 8" guns. Even a 105 mm howitzer (which I believe is the biggest yet fitted in a modern AC-130) would have been quite marginal against warships, the 75 mm which is the biggest they actually managed in WW2 would have been nearly useless.
Finally, the fact is that air attacks against shipping in WW2 were devastating. If a ship had no fighter top cover to protect it, the chance of surviving a determined air attack was very slight. Thus there was no need to develop other strategies, even if attacks failed in one or two cases. Of course, if the ship does have fighter top cover, putting the attacking aircraft in a series of pylon turns is pretty well the worst thing you could do. Might as well just bail out now and save them the trouble. -- 202.63.39.58 (talk) 05:49, 10 October 2009 (UTC)

"Puff" and alternate weapon loadouts

Should it be noted that the name "Puff" came from it being reduced from "Puff the Magic Dragon"? I no longer have the magazines this information came from (it was one of those weekly magazine subscription things from the late 80's/early 90's) to provide a reference point to it, but I am certain someone would be able to come out with that reference.

Also, I remember there was different weapon load outs used at various stages, with 1 or 2 of the miniguns being swapped out for cannons at some point, again, I no longer have the reference material for it, but this was one of those weapons of the Vietnam war that fascinated me and I remember clearly all these little bits of info from them. Does anyone have any information regarding these alternative load outs?

I can also say that, while not factually correct, it is a very common claim regarding the "bullet every square foot" claim. It certainly added to the mystique of the machine. Theloneoutsider (talk) 01:40, 6 May 2011 (UTC)

I remember reading the same about the name, and I think it got named like that after the prototype's name. I don't think it would be inappropriate to add this into the article. The mayor of Yurp (talk) 13:40, 6 May 2011 (UTC)

origin of puff

iirc, this was cause the high rate of fire caused villages in Vietnam to dissapear maybe not the origin of the term, but certainly common during the vietnam war

which means this gunshipp was often used to kill innoncent women and children — Preceding unsigned comment added by 2601:192:4700:1F70:4D8D:8456:F62F:A3F3 (talk) 15:21, 23 October 2021 (UTC)

suspect you recall incorrectly. 7.62NATO isn't going to make a village "disappear". 31.185.62.240 (talk) 01:37, 8 December 2021 (UTC)

Use of modified image?

The image in the info box is heavily modified, including rearranging mechanical parts like the gear and ladder at least. This strikes me as being rather inappropriate. Any thoughts? is there a policy that covers this? If no-one protests, I'll change it in a few days. Gehyra Australis (talk) 03:47, 19 December 2021 (UTC)

It is inappropriate. The editor who modified the image has done this sort of modification numerous times. The basic consensus at [[WT:AIR] was that it shouldn't be done, but new images like it keep being added anyway. BilCat (talk) 03:57, 19 December 2021 (UTC)
Thanks. My main objection is the rearranging of parts. How can the viewer know if the editor got it right? However, it also opens up other questions like: 'I saw a pic of that particular aircraft airbourne, yet my father said it never got off the ground, what's going on? On top of that, the armament does not match the description in the article. Were there variants that have not been covered in the article, or was that modified too? This kind of stuf must erode the credibility of the wiki.
Should the image and editor be reported or something?
P.s., thanks for making the image change. Gehyra Australis (talk) 07:00, 19 December 2021 (UTC)

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