B-26 Marauder weapons thread

[Greg Boeser]

Read Warpath Across the Pacific, by Larry Hickey and company. Tons of strike photos taken by 345th BG planes.

 

[twinwasp]

My wife's uncle, S/Sgt George H Coursen, died on November 23, 1943 when his Marauder B26-C Serial 4134713 crashed in France after being hit by bombs from another B-26. The crew's remains were recovered by local residents and buried in a village churchyard. (which is a story in itself)
I obtained the crash report through the National Archives Trust Fund Board's data base of missing aircrew. I posted in this thread because the listed report listed the planes machine gun inventory as 5-50 cal and 7-30 cal. I am having trouble visualizing where these guns would be mounted. Assuming all guns were on board at the time, where would they be placed?
Also note, the crash report categorizes the loss as due to anti-aircraft fire. The witness reports clearly indicate an accident caused by a US bomb. In the AAF summary table of aircraft losses, the loss is classed as a "bad landing". (Which in a way is true of all crashes.)
I wonder if this is motivated by an understandable desire to protect the conscience of the crew who dropped the bombs, or an institutional need to understate accidents, or simply not having a category for friendly fire?
Below is a scan from the Missing Aircrew Report of the US Army Air Forces 1942-47. Serial numbers of weapons are on the second page.

 

[Greg Boeser]

Hi, Twinwasp.
The MACR lists the weaponry as 5 fixed and 7 flexible .50 caliber guns.
This was the standard for B-26Cs. #41-34713 was an early B-26C-5, the first production block of the C series, built in Omaha, Nebraska. The guns were mounted as follows: one fixed and one flexible gun in the nose compartment, four fixed "package" guns attached to the sides of the fuselage below the navigator's compartment, two in the deck turret in the rear fuselage, two flexible guns in the waist windows (one left, one right), two flexible guns in a manually aimed twin mount in the tail.

Here is a photo from the National Museum of the Air Force showing a B-26C-5 from the same block. The flexible nose gun is visible, but the fixed gun has not been installed. It would appear protruding from the lower right side of the nose cone. Also, both bomb bays are open, and the torpedo mounting brackets are visible on the keel below the main bay. The turret is obscured by the wing, but would be just forward of the waist windows, on the top of the fuselage. The manual tail gun position is visible at the rear. This aircraft lacks the package guns normally attached to the fuselage sides. This is a training aircraft practicing skip bombing in Florida.

 

[varsity07840]

Also note the .30 cal. socket mounts in the bomb bay doors. The AAF insisted on this useless installation and it was soon eliminated from production.

 

[Greg Boeser]

Checking a bit more thoroughly, #41-34713 was a B-26C-6. These were envisioned as a lighter ground attack version of the standard B-26C, which deleted the co-pilot seat and controls. 60 were converted from the B-26C-5 production block, most being assigned to the 323rd BG. By the time the 323rd BG went into action in the summer of 1943, low level operations over Europe had fallen out of favor, and all B-26 missions were flown at medium altitude. Many B-26C-6s were eventually reconfigured to standard B-26C configuration, with the co-pilot position retrofitted. Based on the MACR, this aircraft had not been retrofitted.
Here is a picture showing the position of the fixed guns on the Marauder.

pic source: B-26 Bomber Mister Period Twice nose art | World War Photos

 

[twinwasp]

Hi, Twinwasp.
The MACR lists the weaponry as 5 fixed and 7 flexible .50 caliber guns.
This was the standard for B-26Cs. #41-34713 was an early B-26C-5, the first production block of the C series, built in Omaha, Nebraska. The guns were mounted as follows: one fixed and one flexible gun in the nose compartment, four fixed "package" guns attached to the sides of the fuselage below the navigator's compartment, two in the deck turret in the rear fuselage, two flexible guns in the waist windows (one left, one right), two flexible guns in a manually aimed twin mount in the tail.
View attachment 507003
Here is a photo from the National Museum of the Air Force showing a B-26C-5 from the same block. The flexible nose gun is visible, but the fixed gun has not been installed. It would appear protruding from the lower right side of the nose cone. Also, both bomb bays are open, and the torpedo mounting brackets are visible on the keel below the main bay. The turret is obscured by the wing, but would be just forward of the waist windows, on the top of the fuselage. The manual tail gun position is visible at the rear. This aircraft lacks the package guns normally attached to the fuselage sides. This is a training aircraft practicing skip bombing in Florida.

Thanks - and you corrected my error - all the guns were 50 cal.

 

[Jugman]

TO-01-35EA-1 dated 3-20-1942 Lists the number of the maximum load of 300lbs demo bombs for the main bomb bay as ten. William Wolf has a picture from an internal memorandum from Martin showing 10 250lbs bombs in his book. Later in the book he shows a loading diagram the shows only eight. This diagrams also shows 600lbs M32 and 1100lbs M33 demo bombs which were superceeded by the 40 series bombs some time in 1941. This suggests that at some point early on something changed to allow a pair of 300 pounders to be carried on the outboard racks. In comparison to the other US twin engine bombers the early B-26 had a truly impressive bomb load. Well at least as far as GP and demo bombs are concerned.

 

[Greg Boeser]

There is an instruction in the earliest POI that the additional 300lb bombs can be fitted to station 23 and 26 to fit ten in the forward bay.
I am still looking for the instruction that shows how eight 500lb bombs were carried, since all the manuals I have seen list the max load of 500 lb bombs in the forward bay is six. But Ken Brown in Marauder Man reports eight 500lb bombs to be a standard load.

 

[Jugman]

This Manual from 1944 has the diagrams (pages 169 and 170 that Wolf has in is book. It's clear that the 300lb bomb configuration has a different station configuration with only four station more widely spaced on each of the center racks. However as far as I can tell the bomb stations are fixed in place. If this is true then only six 300lb bombs can fit on the center racks. The stations for the center racks would be 13-14,21-22,29-30. And for the outer racks 17-18,25-26.

It might have been possible to load eight to ten 500lb SAP or 600lb AP bombs in the main bomb bay. The question is; how much weight can the outboard racks support?

 

[alsaad]

Something about weapons modifications on Marauder III operated by No. 39 sqn RAF over Balkans:

Prior to commencement of Marauder operations, but after the work-up period, the 4 x .50 caliber M-2 forward firing package guns were removed from the aircraft, the theory being that they would not be needed in the planned medium-level formation missions. At the same time, the flexible .50 caliber M-2 in the nose of each aircraft was also removed. Its need was questioned, and also it had proved to be something of a nuisance to bombardiers on other squadrons, as well as often causing cracking of the nose plexiglass on these units when fired.

These modifications left 39 with the following; 50 caliber M-2 on ball and socket mount replaced in the nose compartment - 270 rounds, fed to gun from two boxes (one primary, one spare). The reason for the replacement in only two of the Squadron's aircraft is not known. 2 x .50 caliber M-2's in mid-upper (dorsal) turret -190 rounds per gun, fed to the guns from boxes at lower forward part of turret by automatic electric booster motors.

2 x .50 caliber M-2's, one in each waist gun position -240 rounds per gunned through flexible tracks from boxes above each gun.

2 x .50 caliber M-2's in tail turret - 800 rounds per gun fed to the guns through tracks from boxes, one on each side of the fuselage aft of bomb bay, by automatic electric booster motors,

Total: 6 guns - Total rounds carried, all aircraft - 2460.


Typical Bomb Loads:

6 x 500 Ibs GP or MC
plus 4 x 250 Ibs OP
or
8 x 5 00 Ibs GP or MC
Total 4000 Ibs

4 x 500 Ibs GP or MC
plus 6x250 Ibs GP
Total 3500Ibs

4 x 500 Ibs GP or MC
plus 4 x 250 Ibs GP
or
6 x 500 Ibs GP of MC
Total 3 000 Ibs

Other types of bombs sometimes carried depending on type of target
250lb AP (anti-personnel) and 250lb and 500 Ibs GP o rMC with time delay pistols.

​

 

[Greg Boeser]

Do you have a loading diagram for those bomb loads?
The Marauder III was the equivalent of the B-26F or G, which had no rear bomb bay.

 

[alsaad]

Unfortunately not. But so far I managed to conclude by now mixed loads were more common for RAF than for USAAF.

 

[Greyman]

RAF Marauder III loading data

EDIT: from Jan 1944 to Apr 1945 British Marauders reportedly dropped ...

20.4% 1000 lb MC
53.0% 500 lb MC
23.6% 250 lb MC
2.9% 20 lb F
0.1% 100 lb AS

Average bomb load throughout the period was 3,230 lb

 

[MiTasol]

I want to learn more about the low level attacks, especially the Battle of the Bismark Sea. After 10 months of unsuccessful high and medium bombing attacks, the USAAF witjh B-25's, along with A-20's and Aussie Beaufighters attacked a IJN convoy coming down the Slot. To the utter astonishment of the IJN the air attacks sank every single transport ship as well as the convoy commander's destroyer. A couple of weeks later a B-17 did a low altitude attack on an IJN cruiser and left it dead in the water. And the IJN knew the jig was up. There is no place they would be safe. Then the USAAF shot down and killed Adm Yamamoto. After Kicking A and taking names in the Solomans the IJN left, its tail between its legs and its head down.

It was not true skip bombing but low altitude bombing. It was taught at my home town, Columbia SC, using nearby Lake Murray as a bombing range. I recently bought a book about the man who thought up that method of attack, entitled, "Indestructible."

Do a web search for the Damien Parrer documentary Battle of the Bismark Sea. Good footage of the attacks including of machine gunning liferafts and survivors

 

[MIflyer]

A book I have by a B-26 navigator in the ETO said they had ONE mission in which they used the side package guns and the gun in the tip of the nose. They were told to bomb a target and then go down and strafe. In order to use the nose gun the bombardier had to remove the Norden bomb sight, and in that case after they dropped the bombs he removed it and handed it to the navigator, who usually sat behind him in the nose (which had no seats).

But I also read of a case in which a BF-109 made a pass at a B-26 formation and a B-26 on the outer edge dove after the German, blew him out of the air with the side guns and then pulled back up into formation.

 

[Greg Boeser]

In Alaska, the problem of forward firepower was dealt with in a different way. At least one, and possibly more, had the bombardier's position removed and a pair of .50 caliber machine guns and a pair of 20mm cannon were installed through the nose cone. The additional weapons were scavenged from wrecked P-38s or P-39s. This conversion is believed to have taken place after the 73rd Bomb Squadron moved to Adak, in the fall of 1942.
View attachment 354547
Captain John Pletcher, 73rd Bomb Squadron, 28th Composite Group, flew this plane (or one like it) while leading an attack against the 4000 ton Japanese transport Cheribon Maru, on 26 November, 1942, sinking the vessel in Holtz Bay, Attu

I have now identified at least three Alaska based aircraft with this modification. 40-1558, 40-1506 (Pletcher's plane) and 40-1447.
It turns out this modification was done at Elmendorf Field as early as August 1942. However, I have not found evidence of combat use except for Pletcher's Thankgiving Day attack on Cheribon Maru.

 

[MiTasol]

I am probably the last to find this site but here it is for any that missed it

https://b-26mhs.org/

 

[Greg Boeser]

I have now identified at least three Alaska based aircraft with this modification. 40-1558, 40-1506 (Pletcher's plane) and 40-1447.
It turns out this modification was done at Elmendorf Field as early as August 1942. However, I have not found evidence of combat use except for Pletcher's Thankgiving Day attack on Cheribon Maru.

Add #40-1555 to list of modified B-26 strafers. Both 40-1447 and 40-1555 were damaged in landing accidents on 27 Aug 1942 at Elmendorf Field while testing the installation of the nose guns.

 

[Micdrow]

Greg, found this on the web and though you might be interested. Guessing they did this to make it appear to be shooting bigger guns to the enemy when attacking from the rear.

 

[fubar57]

D-Day stripes as well?