Aircraft and the 4 rules


June 30, 2003, 02:15 AM
We all know the utter importance of the four rules.

Something occurred to me; many of us have been to airshows. I recall very closely examining the business end of an A-10's little peashooter. :scrutiny: :uhoh:

Do the four rules simply not apply to aircraft at airshows? I mean, all of those people walking around in front of all those guns (directly in front of the muzzle) or even looking directly down the barrel most definitely violates the rules.


If you enjoyed reading about "Aircraft and the 4 rules" here in archive, you'll LOVE our community. Come join today for the full version!
June 30, 2003, 02:24 AM
I dont know about most people but personally I would not be sticking my head in front of a 20mm cannon.

Wonder if they use Surefires for borelights :)

Fly Navy
June 30, 2003, 02:31 AM
Ahem, that'd be 30mm on the A-10.

Yes, I'm a smart-??? :D

June 30, 2003, 02:36 AM
That was a typo. You see the "3" is next to the "2" key :):neener: :D

June 30, 2003, 04:09 AM
and frankly don't wanna hear any "why DO you think that" responses, b/c i am just explianing how i personally am able to deal with the situation.

first off the four great loves of my life are, My wife, aviation, firearms of all types, and military history. and in numerous places those four converge in differing manners. so I go to (good) airshows as much as i can, and also try to treat all guns as loaded as much as possible. so if i did not have SOME way of dealing with the fact of the weapons aboard the "static display" aircraft i would be a nervous wreck.

now here's HOW i;ve come to deal with it. on Warbrds (restored obsolete military Aircraft) the guns are either NOT installed, fakes, or have been rendered non-operable (i think this is a FAA or similar requirement) so i tend to think of those gunports as containing nopthing more than a lump of steel and a pipe.

on modern military planes, at least american ones, 99+% of the guns are some form of M-61A1, an update, or a system (like the A-10's avenger) with a similar operating system. these guns are not only operated (cycled) by an electric motor, but round ignition is also electric. thus "no power, no fire" to assure this many(if not all) base commanders (assuming no military wide edict for such) in addition to multiple checks to assure the removal of all ammo, also have the power and control leads to the onboard weapons of any airshow static display aircraft disconnected. for a system such as the Vulcan (M-61) this is analgous to removing the trigger group, removing and placing in opposing corners the firing pin and hammer, and then putting lock tite int he action to hold it closed.

i won't stand around looking down the Maw of one of these things but i am no more worried about being swept my one than i am about driving or walkng down a road at a Civil War battlefield that is lined with spiked cannons.

June 30, 2003, 04:24 AM
Heh do you wet yourself when you walk past the waist turrets of a B-17, too?

June 30, 2003, 09:22 AM
I wouldn't look down the barrel, but you have realize that on some aircraft (e.g. F-16) the pilot passes right in front of the cannon as he climbs into or out of the aircraft. If their not worried, I'm not worried.

M2 Carbine
June 30, 2003, 09:56 AM
If I worried at all it would be when the aircraft is flying.
See Detritus's post about the operating system.

Being a pilot for 43 years I can tell you pilots make mistakes.
I've made some winners.

June 30, 2003, 10:46 AM
As detritus said, most current and historical aircraft weapons, going back to WWII or so, are fired electrically.

In the case of a gun or cannon a solenoid, basically an electromagnet, is often used to pull the weapon's trigger. Aircraft ammunition is also quite often electrically instead of mechanically primered. One example of this is the 20x102mm ammunition for the M61 series. These days, the weapon's action and the ammunition feed system are often externally powered as well. The major exceptions to this seem to be flexibly mounted lowcaliber (under 20mm or so) and/or low-rate-of-fire guns.

If the plane's power system is off, the gun shouldn't be able to fire for several reasons.

There may even be a mechanical safety. I'm no fighter aircraft expert, but it wouldn't surprise me if one of the 'Pull before flight' ribbons you see hanging on parked aircraft is for a firing inhibitor.

Then there is the issue of whether the gun is loaded with live or inert ammo. Inert ammo at an airshow wouldn't surprise me one bit.

So unless someone pulls the right pin, gets into the cockpit and then starts pushing buttons I think the admiring public is safe. :D

Having Rapid Fire lieing around for questions like this can be handy.

ErikM :evil:

Double Naught Spy
June 30, 2003, 01:20 PM
Why do you think aircraft are somehow special, Drjones? Such rules would also apply to other weaponry such as artillery, tank guns, and the like.

So do the four rules apply?

Let's see, three of the four rules pertain to the person controlling the gun. At the airshow, the guns are stationary in planes and are not being controlled. Instead, it is the public that walks in front of the planes and looks down barrels. The one rule they violate is not assuming all guns are loaded all the time. As for the other three, they are not pointing the gun themselves so the rule about not pointing the gun at anything you are not willing to destroy doesn't apply. None of these pedestrians has access to the trigger and so keeping your finger off the trigger until ready to fire does not apply. Neither does needing to know your target, backstop and beyond.

June 30, 2003, 02:06 PM
Does that mean you should never stand in front of a gun case at the gun store?

Unloaded firearms with noone and or nothing at the controls do not pose a serious threat to me or my family.

June 30, 2003, 02:14 PM
Aircraft weapons, everywhere I've flown, are kept loaded but safed with pins in and plugs disconnected on the flight line, during preflight, taxiing out and performing pre-takeoff busywork. Only when the flight is ready to take the runway for takeoff (or taxied onto the cat aboard ship) are the pins removed and weapon release/fuzing connections made in an elaborate dance of ordies and aircrew keeping hands visible to each other at critical times. Reverse on return, whether weapons are present (hung) or not.

Sort of like the four rules.

TFL Survivor

June 30, 2003, 02:23 PM
Unloaded firearms with noone and or nothing at the controls do not pose a serious threat to me or my family.

1) What is an "unloaded" gun?

2) Why do you dismiss a mechanical failure as a possibility?

June 30, 2003, 10:00 PM
I have heard that on most of the modern airplanes in the US Inventory, have rounds loaded in the gun to aid in the balance of the airplane. Can anybody speak up on this??


Navy joe
June 30, 2003, 10:24 PM
I don't look down them out of habit from being around them in a operational enviroment, with the right front strut precharge a F-18 cannon points right at my head. An AH-1W manages to point at everyone. I have read of a few accidents where the gun was electrically actuated for the purpose of gun maintenance only come to find out it had a few rounds left in the chain. Most recent I remember was with a CIWS, no one was injured, but...

So, If I see folks working on the guns, uploading, or downloading I steer clear. And yes, some aircraft do normally carry a full drum for weight and balance. It will be training rounds, but that only means an inert projectile which is fully capable of firing. At an airshow I would consider your risk to be less than minimal.

Other fun with ordies. A popular disarm technique is to not read the checklist, not have a clue what you are doing, but apply ground power and cycle the "jettison all" switch. Amazingly enough, it works :uhoh: . This has been done. More common is the drop tank shuffle where a couple of strong fellows get together to lift off an Empty drop tank from a wing station this is usually preceded by someone saying "yeah it's empty" from relying on how the tank sounds when tapped with a wrench. The releases are actuated and two ordies find themselves with lifelong severe back injuries because they tried to hold up a tank half-full of fuel.
Then there is always the F/A-18 Sidewinder AD where a Sidewinder missile goes merrily skipping down the flight deck after popping free of a F-18 wingtip rail on carrier arrestment. Always gets your attention.
I've gone to claim some empty ammo cans only to open one up to find some spare electric primed HE 20mm rolling around loose
:scrutiny: How about I go away while you guys throw that overboard M'kay? I don't want to be there.
Then there is always that one about the Zuni rocket. Oops.

June 30, 2003, 10:33 PM
Ok heres the 411 on the airshow aircraft.

When we send our A-10's to the airshow the static display aircraft gun is empied. All the bullets are removed and weight ballast is installed in the nose section to offset the weight difference.

Munitions hangin on the pylons are inert. Dummy munitions all painted up to look pretty. They do not have the explosives, rocket motors or bomblets in them.

The only thing that is armed on the aircraft is the ejection seat. And most of the time they are dearmed during the show to keep from having an accident happen.

As for the other MDS aircraft I would assume that they are prepped the same. We all have Tech orders specific on static display aircraft.

Jets on the flightline during normal ops are loaded and ready to go. Just about every gun the fighter aircraft carry has a clearing cycle after the gun is fired. On the A-10 it cycles back 7 rounds. So when the pilot pulls the trigger the gun will rotate without firing until the first round is cycled thru.

It is checked before flight and after flight as well.

So there you have it in a nutshell from an A-10 guy.

June 30, 2003, 11:22 PM
I have never heard of, or seen, live or practice ammuntion used as ballast. There are different types of dummy rounds and they are of the same weight as a live round for various reasons, a ballast load being one of them.

The clearing cycle for the M61 in an F18 is five to seven rounds "forward". This means that once cleared, if there is any live ammuntion remaining in the gun, there will still be live rounds in the gun's "rotor". If you looked down the barrels with a flashlight, you will indeed see the projectiles. What the clearing cycle does is cause the gun to rotate the rotor around enough to "unchamber" the live rounds. Unchambered rounds cannot fire because of internal mechanical workings of the gun when the gun is in "clearing".

Also, electrical primers CAN be percussion initiated. (Not probable but possible) ...

June 30, 2003, 11:49 PM
Does that mean you should never stand in front of a gun case at the gun store?When I read this I thought about loaded firearms in store gun racks. Folks being folks, I'd bet at least one store in any major area has (for some reason) one rifle or shotgun charged and ready.

I can see a worker bee deciding that this is his protection mode - in case he's in the show case under duress.

Then there's the guy who just "retired", leaving one of these "bombs" in the rack for whatever the ultimate result.

I wonder how many of these occur...?


June 30, 2003, 11:51 PM
Keeping your powder dry?

I'm still trying to get to Pungo... gotta get this EBR locked in.


July 1, 2003, 01:02 AM
We only use dummy rounds to do gun ops checks.

Live rounds go back in after the ops checks are done. Most of the live rounds are TP or Target Practice. We also fly HEI and Combat mix.

The HEI comes out from time to time to be shot but the combat mix only comes out in wartime.

.I have never heard of, or seen, live or practice ammuntion used as ballast

We use ballast plates instead of dummy rounds for weight. Our Cg or Center of Gravity is pretty crucial in fighter jets. So if you take out the live ammo you have to offset the weight loss. IE installing ballast plates.

You can see empty shell casings in the gun barrel if you have a powerful enough light. Our clearing cycle is 7 rounds of empty brass

If you enjoyed reading about "Aircraft and the 4 rules" here in archive, you'll LOVE our community. Come join today for the full version!