Cannon Failure at Fort McHenry on September 16

[Prairie Dawg]

Hi Folks:
I thought some of you might find this interesting.

My pard & former Ohio Frontiersman champion Marcus Allen was attending the 200th Anniversary of the bombardment of Fort McHenry last weekend. He served on the cannon crews during that weekend as the # 1 gunner (the person who fires the cannon with a linstock - burning rope). On Sept 16 there was a cannon failure and the breech of the cannon blew open due to apparent failure of the cannon barrel casting.

Marcus was not on the cannon that failed. The cannon that blew out the breech was the identical sister cannon to the cannon that he was firing on Sept. 13.

Here are pics of the failed cannon.

--Dawg

The Official National Park Service Bulletin on the cannon failure:

Cannon Breech Failure

Issued By The National Park Service September 16, 2014

BALTIMORE -During the firing of a reproduction historic cannon at Fort McHenry National
Monument and Historic Shrine on September 16, 2014, the breech of the gun failed, according to the
National Park Service.
At approximately 11:30 a.m. on September 16, the park's living history gun crew used black powder
to fire a salute to a passing ship as part of the weeklong series of events celebrating the 200th
anniversary of the Star-Spangled Banner. The firing of black powder in the reproduction cannon
caused the breech to dislodge. The breech is the mass of metal at the rear end of the cannon.
There were no spectator injuries;one of the members of the cannon crew suffered minor flash burns
on one hand.The cause of the accident is under investigation.
The NPS has suspended the black powder historic weapons firing program at Fort McHenry. The
immediate area around the Water Battery remains closed but the rest of the park remains open.
The cannon crew was saluting the U.S. Coast Guard Cutter Eagle and The Pride of Baltimore II.
About Fort McHenry National Monument &Historic Shrine

 

[MikeJackmin]

I'm no engineer, but to my untrained eye it looks like only about half of that metal has been freshly torn away. The other half looks like it cracked free some time ago.

Note to self: never stand directly behind the cannon.

Good on them that they didn't have a serious injury here. All those good safety habits really pay off sometimes.

 

[zimmerstutzen]

My personal rule is at least a bore thickness of metal in all directions behind and to the side of the breech. Looks like something I would have measured and NOT fired.

 

[72coupe]

I've seen worse.

 

[IlikeSA]

Thanks for the post and pictures!

 

[redbone]

72coupe: can you tell us the story behind the picture?
Tnx.
RBH

 

[Jim Watson]

Just spit the cascabel right out.
Chill line in the casting?

 

[rcmodel]

Good thing they weren't shooting a real cannon ball in front of the powder charge!

Blowing up with a blank load is pretty dang bad!

Had it had a ball in it, the back end would be going faster then the cannon ball!

rc

 

[WestKentucky]

That's scary thin walls where that blew out...but RC is right, how crazy is it that this happened with a blank??? Whoever made the molds for that casting set the bore too far back from the looks of it.

 

[rcmodel]

Makes you wonder it it had ever been fired with a full charge & a ball ever before?

rc

 

[WestKentucky]

Gotta question the 2 tone look on that pour as well...was it a barrel sleeve with a casting around it or was it a 2 part pour that cooled too much between pots? With it being a reproduction it could easily be very poor quality material and craftsmanship, and I have never heard of a reenactment type event in which a gun fires a projectile of anany type so I bet it never saw a ball.

 

[Jim Watson]

I have never heard of a reenactment type event in which a gun fires a projectile of anany type

I have.
My only close exposure to muzzleloading artillery was an outing with a battery practicing for a live fire match. A 20 lb Parrott Rifle will throw a solid zinc shot very well. A little 2 lb "grasshopper gun" not so much; but it would sure slow up a charge with a load of bagged musket balls. They had a real blockade running British Blakely Rifle, too; a literal junkyard rescue. Rough bore and not real accurate, but still neat to see and hear that 140 year old gun talk.

 

[rcmodel]

The whole barrel casting looks too rough to be any real cannon I ever saw.

I don't think I have ever seen one with a mold parting line like that one.

I'm thinking cast iron repro barrel of some kind made for impressing the tourests.

rc

 

[kBob]

The St Barbara folks at St. Augustine Castillo de San Marcos used to fire their "blanks" with a cloth bag of saw dust slightly dampened rammed down the bore. The bag fragments fell away thirty yards or so down range and into Matanzas bay.

My mother in law has moved from St. Augustine so no chance of me signing up for the cannon course now.

A fair number of cannon at Castillo de Dan Marcos from when it was built through the civil war and also a hot shot furnace. Both decent firearms museums have closed, one to BATF and the other to death of the owner. Not as much of a fun trip to me now.

72 Coupe's photo always reminds me of when the Army was trying to upgrade the 8 inch by adding just one more increment bag. The one that let go at Sill killed several crew members and the wreckage gave me the willy's every time I pulled a lanyard.

-kBob

 

[72coupe]

Kbob many of the things we use in war are dangerous. Hand grenades scare the crap out of me.

 

[rodinal220]

That cannon should never have been fired. The NPS need a REAL program for accepting repro cannon and training crews.

The liner looks stout enough,I would postulate about 1/2" wall thickness. But it appears that the liner may have been without a breech plug or an improperly installed plug. You cant have the powder chamber right up against the cascabel.

If the breech plug was press fit that is a no no. I do not see any evidence in the photos to suggest any welding. The liner was set too far back,right up to the cascabel and may not have had a breech plug.

The repro cannon barrel supplier needs to check on their QC program before someone gets killed or injured.

 

[BCRider]

Since this a repro I'd suggest that the outer jacket was poured around a tubing core "liner". At least this is what it sort of looks like. It's possible that the liner/core had a cap welded on. But from the fracture line in the casting around the liner it would seem like there simply wasn't enough metal in the casting at the corner to hold things back. And if there was no cap or the cap was minimally welded on and they relied on the cast iron to hold it all together then they misjudged just how much cast metal is needed.

There's also a wide variety of cast iron alloys and pouring methods and post casting treatments designed to give the cast iron some fatigue resistance. It may well be that such was not used.

But mostly I just think that the liner should have been shorter so there was more metal thickness at the breech. The outer grey cast iron fracture ring shows testament to how little the wall was at that point. For example if the liner had stopped at the back edge of the last thicker outer "band" then the walls across the breech would have been easily twice as thick and we would not be seeing this discussion thread.

 

[kBob]

72 Coupe,

Only time I was worried about grenades we were using some old Mark II Pineapples in my enlisted Infantry days.......and cooking them off.

Raised some hackles on some folks a few years later when I was instructed to "just throw it like you did in the Infantry" with an M26. AI freaked when I let the spoon fly off in the pit with us, got my air burst right at the target though.

Did you ever set a pair of injector razor blades between the fuze and shell body? I had a boss that did and he said they made and interesting sound going down range......could not help but wonder what that did to accuracy though.

-kBob

 

[CANNONMAN]

Is there or are there any pic's of the breech? Also, I agree that, "my gosh, who designs a cannon to have the weakest spot in the highest pressure zone? In ratio, none of my cannons come close to this design. Very curious as to who, how and why the design was approved. And absolutely I agree that with shot this was pipe bomb! Anyone know how much of a charge? Range? Thanks for thread.This is a classic example of elastic failure. This design could have well stood a hydraulic pressure equal to or greater than that delivered by the hammering effect of the blast. An example of how dangerous it is to of believing all forces of this nature are equal. This design works fine in vitro and not so much in vivo. Simple Newtonian physics are not adequate when it comes to safety and wellbeing. The world is not flat.

 

[TheRodDoc]

The news reported that the 100 lb. plug was blown 300 feet away and some small pieces found to 400 ft. Cannon made by Cannons Online Inc.

 

[breakingcontact]

Kbob many of the things we use in war are dangerous. Hand grenades scare the crap out of me.

Throwing a live hand grenade is an "exhilarating" experience!

 

[4v50 Gary]

Thank goodness there were no fatalities or major injuries.

 

[rcmodel]

Throwing a live hand grenade is an "exhilarating" experience!

So is having a raw recruit drop one in the pit with you standing behind him.

Slow motion kicks in.
You see the pin in his sweaty little hand.
Then he cocks back, and drops it!

You hear the spoon ting off.
And watch it spinning in mid-air beside the falling grenade.
You hear the primer pop.
You hear it thud when it hits the ground.
Then kicking it down the grenade sump hole in the pit 1/2 second before it goes off.
Then knocking the recruit away from the sump and out of the way.
Then you can't hear for three days.

It all takes less then three seconds, but seems more like three minutes.

I'm here to tell ya, That is a Real Attention getter to pucker up the old pucker string!

rc

 

[Jim K]

That certainly looks like a lined bore. Whether the rest of the gun was cast around the liner or the liner was inserted into the bore, I don't know, but I suspect there wasn't enough metal at the rear of the liner.

The old ones usually didn't let go that way, the reinforced breech blew off the rest of the barrel. Either way, I am glad no one was standing behind that cannon when it let go. That would have been a rather disturbing experience.

Just FYI, the maker's web site says:

Warning - As with all Black Powder Ordnance, cannons are inherently dangerous and should be handled by trained and experienced personnel ONLY. The manufacturer DOES NOT CONVEY ANY ASSURANCE OR WARRANTY SAFETY AS TO USE with Black Powder or "live fire."


The site also shows an old(?) drawing of a cannon with the bore much shorter than that one showing that the old timers knew more about casting cannons than modern makers seem to.

Jim

 

[Jim Watson]

I see the light gray ring, but I think it is a fracture surface, not the end of a liner.