Any AN-MK1 Armor Piercing and AN-M58/ AN-M59 SAP Bombs out there?

[Oct41]

I went to the Naval Air Museum in Pensacola Florida last weekend(absolutely amazing museum!) and was looking at the large number of WWII bombs on display. Upstairs in the F4F Wildcat diorama, a number of bombs are on display. One in particular that caught my attention was the AN-MK1 AP bomb. It's in a darker part of the display and was a pleasant surprise to see. I have only seen them in tech manual pictures. It even has the hydrostatic fuze attached. I was curious if anyone out there has one in their collection? It is a really neat looking piece.

In the display around the corner is an F6F Hellcat being worked on in a hanger bay with bombs scattered all over. They had a couple of what looked to be AN-M58 and AN-M59 SAP bombs laying around. I was also wondering if any of these have made it into private hands?

I would love to try and fabricate one of each of these bombs but would need to figure out the dimensions. If you are into airplanes and ordnance definitely a museum worth going to!

Thanks,
Scott

 

[HAZORD]

Scott,

Your mention of the 1,600 LB. AN-Mk1 AP bomb is the first I have heard of in a museum, as I have been asking around. I have one, but it came without a tail fin. I also have it's 1,000 Lb. little brother that is also missing fins. I've been hoping to fabricate fins for each of them, and only had a few dimensions to work from. I wish you would have taken photos of the one in the museum and posted them. I'm going to have to contact them to see if I can get them to take some measurements.

 

[Oct41]

You are in luck!!! I took a number of pictures of it and just have not had to time to download the photos. I am happy to share what I have and will post them this weekend. It is painted green (not olive drab but like a forest green) with no stencils or other markings on it. I got pictures(as much as I could with it being in a display) of the side lugs/top lugs/hydrostatic fuze and fin. People walking through the display were probably wondering why I was taking such detailed pictures of a bomb. I think its awesome that you have both versions of this type of bomb as it is a slick looking design. I'm not sure how hard they are to find but I thought it would be awesome to even fab one to stick in my collection.

 

[AE501]

Bomb 1600 lb AN - Mk1 AP

Hazord
Here is a drawing and info on the Bomb 1600 lb AN - Mk1 AP. It gives fin dimensions so with Oct41s photos you should be able to make a fin.
I also have dwg & info on Fuze, Tail, Mechanical Impact Mk 28 if required. There is no mention of a hydrostatic fuze for this bomb, but this was 1942 so the need may not have arisen. There is a dwg & info for a Mk 24 mechanical hydrostatic fuze, which at that time was for use with a 650 lb depth bomb and info only for a Mk 29 used in same.

 

[Oct41]

Sorry for the delay. Here are the pics of the bomb.

 

[Dreamk]

Navy bombs are always a treat. Thanks for the pics!
Here're some drawings of the AN-Mk228 fuze.

 

[HAZORD]

The bomb you show must be a late war version. The one that I have is like the drawing that AE501 posted. It has bolt-on bands with bomb lugs, that wrap around the body, and a band in the middle for hoisting the bomb into the plane. My bomb is most likely Pre-war, because it was originally painted yellow, which changed in 1942. The 1,000 Lb. AP bomb that I have has the bolted on bomb lugs like the one you have shown in your photos, but it was originally yellow too.

By the way, the machine just to the right of the bomb in your photos is an acetylene generator. You put powdered carbide in the hopper at the top and it feeds it into water in the tank to power an acetylene torch. I grew up with one just exactly like the one in your photos.

 

[Dreamk]

The 1600lb Navy bomb has as a matter of fact a 4-steps development (3 submodels of Mk1 and then the AN-Mk1) so as to fit to various possibilities of bomb racks and therefore of operational use.



What is shown in the photos is indeed an AN-Mk1 with integral side trunions for dive bombing situations, together with suspension lugs, "British" suspension lug and hoisting lug. The earlier Mk1 models used hoisting band instead together with suspension band.

In post ww2 models the trunions and the "British" lug were suppressed.

 

[HAZORD]

Dreamk,

Thanks for the documentation of the various models. My bomb doesn't have the grooves around the body, but it does have indentations in the top, into which a cone shaped protrusion on the inside of each band fits to locate the band at the proper place.

Would you by any chance have any drawings of the tail fin assembly, or a model number for the fin assembly? If you look at the photos posted tonight, you will see that the cutouts in the sides of the tail fin extend much farther towards the back of the fin than are shown in the drawings you posted. The cutouts extend back further due to the length of the tail fuze and the need for the airflow to engage the spinner on the fuze.

 

[Dreamk]

All what I have on the fin is as follows:
1955 publication:
An-Mk1
Fin assembly: Dwg 294201
Fin Weight: 28.50lbs
Fin Span 20.6 inches
Fin Length 21.1 inches

September 1943 publication:
AN-Mk1
Tail: Sheet steel, 4 vanes welded to tail cone, interior box-type struts, cone secured to body by tail lock nut.
Length of tail 20.5" approx.
Width of tail 20.6" approx.
Interestingly this publication gives the fuze as the AN-Mk219 or Mk219 instead of the AN-Mk228, although the drawing attached to it bears mention of the AN-Mk228 fuze.

Henry Belot of Deminest gives the tail dimensions as 432 mm long and 406mm width

 

[AE501]

Bomb AP 1600 lb

I was in my back bedroom tonight having a sort out and I found this, which is now 1944. So they have still not found a reason by November '44 to have a hydrostatic fuze. It says this is the only fuze to be used with this bomb.
I hope this may be of some use.
There is more blurb if you need it.
I found this about bands which seemed to be for you.
I just noticed these dimensions on the bomb, which you should be able to scale from.
This is my 3rd edit, if permitted.

 

[Oct41]

I was happy to help with the photos! I have been traveling due to work and was not able to post. Now that I am back home for a while I can dabble with the bomb stuff.

It's funny you mention the acetylene generator. My parents acquired one years ago out of an old barn and it has floated around their place for years. After seeing the display I immediately talked them out of it. If anyone needs pictures of the stencils on it I took detailed photos of those as well.

I can't wait to see your finished fins. Maybe you could do a post showing the fabrication process. I have followed your other restoration posts in the past and have found them very interesting.

 

[HAZORD]

I want to model them in CAD, and do formal drawings for them, then have a sheet metal shop do the Fab, Laser cutting the metal, forming, and spot welding.

I need info on the fins for the 1,000 Lb. AP bomb fins also.

I also need to contact your Florida museum and ask if they will take a couple of measurements for me.

I wish I knew where to go to get a print of the assembly drawing, and get prints of the components used in the assembly.

 

[AE501]

View attachment 112260View attachment 112261View attachment 112262View attachment 112263
1 Fin dimensions for 1000 lb bomb in same mode as 1600 lb bomb.
2 More text.
3 Fin and band arrangements for 600 lb AP showing close up of fixing etc for metal worker.
4 600lb AP.

 

[HAZORD]

AE501,

I appreciate your attaching the drawings, but when I click on them it says invalid attachment and says to contact the administrator.

 

[AE501]

An-mk1 & mk33 ap bombs

I do not know what I did but it was different.
I will try again.

 

[Oct41]

Below is the link for the museum. The bomb is located on the second floor in the F4F Wildcat exhibit on the right side in a tracked bomb/torpedo carrier. Hopefully they can help with the exact dimensions. I took my pictures with the hope of one day using them to fab a replica.


http://www.navalaviationmuseum.org/