Consolidated, later Consolidated-Vultee, built the B-24 Liberator, the other workhorse heavy bomber in the USAAF. The same airframe saw service as the C-87 Liberator Express and as the C-109 tanker. The B-24 was the subject of Design Analysis articles in the November, 1944 issue of Industrial Aviation, where the focus in on the B-24J, and the July, 1945 number of Aviation, which doesn't specify model but also features the B-24J.
A preliminary draft, [ PDF, 21.2 MiB ], recovered from microfilm, of the Aviation Design Analysis article includes some additional material. A later draft [ HTML ] is taken from original magazine sources.
The Industrial Aviation Design Analysis article [ HTML ] provided the rendering responsible for the wallpaper files here.
Air Tech (ie, the USAAF Technical Training Command) had a short-form design analysis of the B-24D in "Air Tech presents the B-24 Liberator" [ HTML ].
While the B-24 was the most-produced 4-engined bomber in the US inventory and was extensively modified and developed during its career, it was not as well documented in the contemporary American press as was the B-17. Some of the variants that were documented are illustrated on their own page.
The Liberator is featured in a number of articles, both on production and on operations:
- A news clip [ HTML ] in the "Aviation News: Defense" column for March, 1940, mentions the first flight of the XB-24 and gives a capsule description.
- "B-24s in Quantity Production" [ HTML ] describes the layout and operation of Consolidated's San Diego plant.
- Sweeping Planes Off From The Floor" [ PDF, 9.7 MiB ] , [ HTML ] describes Consolidated's success at salvaging production scrap.
- "Old Bag of Bolts" [ HTML ] is a missions story about an early B-24A.
- "Single Assembly Line Produces Both Bombers and Transports" [ HTML ] describes the main elements of the production of a B-24 and the changes made to produce C-87s on the same production line.
- "Modification Centers
An American Military Innovation" [ HTML ] describes Consolidated Aircraft's approach to the mod center.
- "Reduction of Man-Hours In Aircraft Production" [ HTML ] describes the methods Consolidated Vultee used to control construction labor and time in producing the Liberator.
- "Pink Lady" [ HTML ] is an almost stream-of-consciousness account of a B-24 mission from North Africa.
- "Will It Run?" [ HTML ] tells the story of the development of the Willow Run plant and lays out some of the ongoing problems in its operation.
- "American Colossi" [ HTML ] is a color Gallery photo of a B-24 flying over the Grand Canyon.
- "Liberators by Consolidated Vultee" [ HTML ] describes operations at the Fort Worth plant.
- "Liberators by Ford" [ HTML ] describes operations at the Willow Run plant producing B-24s.
- "Versatile Bomber" [ HTML ] , [ PNG ], describes and illustrates the differences between B-24D and C-87.
- "How Fewer Build More Bomber Nose Sections" [ HTML ] describes the construction of B-24 nose sections.
- "Piloting Big Bombers Is Big Business" [ HTML ], "Building the AAF Part IV," describes the process of training a multi-engine pilot, using B-24 training as their example.
- "Consolidated Vultee San Diego Production Flow Plan" [ HTML ] describes Convair's production and production-control methods. While this article describes actions at the San Diego plant, the same methods were used at their Fort Worth plant.
- "Liberator Service Dock" [ HTML ] describes a transportable (in knocked-down form) structure designed to protect service crews in the field.
- "Convair Produces RY-3 Military Transport" [ HTML ] introduces the RY-3 cargo version of the PB4Y-2 Privateer.
"Aviation's Sketchbook of Design Detail"
- A Curtiss Electric Propellers ad, "There are Hundreds More
on the way to finish the job." features a color painting of a Liberator in RAF markings on a hardstand in a nighttime scene. Plane is seen from 2 o'clock high.
- "B-24s in Quantity Production" [ HTML ] includes three drawing/diagrams
- A Consolidated ad, "Now we make it official
The Liberator," features a scratchboard drawing of a B-24D.
- A Duotone front cover Pratt & Whitney ad, "Liberators Strike Far and Wide," features a color (well, Duotone) painting of B-24Ds over cloud cover with shipping showing through gaps in the clouds.
- A Roller Bearing Co of America ad, "RBC needle bearings help set them down safely," features a stylized drawing of a B-24 and a line drawing of the (righthand) main landing gear of a B-24.
- A Pesco (div of Borg-Warner, fuel pumps) ad in the "Performance Controls the Air" series features a color painting of a B-24D on final for a dawn landing, seen from 1 o'clock low. Two other B-24s are shown in background.
- cutaway drawing of the fuselage of a B-24D fuselage.
The plane illustrated has the Bendix remote-sighted belly turret.
- nose-fuselage mating jig
- nose construction fixtures
- cutaway drawing of the fuselage of a C-87, configured for freight
- cutaway drawing of the fuselage of a C-87, configured for carrying passengers
- straps used in mating nose and aft fuselage sections as used by Ford
- A color front cover Pratt & Whitney ad, "Blitz for Blitz," features a color painting of B-24s in rather fanciful attack action, with explosions, guns blazing, forward bomb bay doors open on foreground plane. View is from 2 o'clock low.
- A drawing from a Thompson Products ad, "One of our Boys helps pry the lid off Truk," shows a photographer and camera looking through a waist window at a shipping scene below, with a B-24D in background. Photographer is wearing heavy flight gear.
The drawing illustrates the activities of a former Thompson employee.
- diagram of the fuselage stations of an early B-24, probably a B-24D.
This diagram shows the location of the tunnel gun hatch.
- diagram of the heat flow for de-icing and cabin heat
- production flow plan at the San Diego plant
- A news clip, "Quick release for life raft," illustrates and explains the stowage and release of the life rafts.
- The Design Analysis from Industrial Aviation magazine includes a number of detail drawings and diagrams:
- A Curtiss Electric Propellers ad, "Year Round Service over the North Atlantic," features a color painting of a C-87 flying in icing conditions. View is from 2 o'clock high.
- A color front-cover Pratt & Whitney ad, "Privateer on the Prowl," features a color painting of a PB4Y-2 Privateer over ocean and islands, seen from 2 o'clock high.
- drawing showing engineering changes on a late-model B-24, as built at Ford
- drawing showing proper use of safety wire, as used at Ford
- drawing showing control cable routing
- assembly instructions for an elevator
- drawing showing furnishings of the righthand wall of the nose section
- photo and detail line drawings of an engine nacelle, from a Rohr ad
- 3-view drawing of a B-24J with principal dimensions
- line drawing exploded assembly view of a B-24J
- detailed drawing of nose gear and mechanism
- construction of wing center section
- construction of wing tip
- A line drawing from "Aviation's Maintenance Notebook" shows a mobile, sheltered work platform for working on engines of large aircraft. Four examples are drawn with a stylized late-series B-24.
- An Auto-Lite (electrical wire) ad, "Lone Wolf of the Pacific Skies," features a painting of a PB4Y-2 Privateer in flight, seen from 2 o'clock high.
- plan and elevation of a B-24 converted to luxury civilian transport
- A series of two-page ads from Consolidated Vultee Aircraft Corp done in a comic-book/instruction-manual style featured the B-24 and C-87 as integral parts of the combat and transport forces, respectively:
- "The Joker in Air Power" is a bid to keep tax dollars coming in to support development of new types. It includes 2 drawings of B-24Js.
- A Norma-Hoffman (ball bearings) ad, "Consolidated Aircraft B-24 land bomber gets hair-trigger control on Norma-Hoffman precision bearings," shows a B-24A from 2 o'clock high. Plane has "meatball" insignia and striped rudders.
- A news clip with photo from December, 1940, shows a Liberator in RAF livery on the ground at San Diego.
- A Fafnir Ball Bearing ad, "The Element of "Chance" is No Trifle," shows an early B-24, probably a -D, in flight, seen from 10 o'clock. Plane has "meatball" insigne. As is typical of early-war photos, this one shows no armament or tail number.
- A gallery photo shows a Liberator B MkII in flight in RAF livery, seen from 2 o'clock high.
- "War in the Air" [ HTML ] includes a photo of a B-24A on the ground in Singapore during a round-the-world flight This would be 40-2373, flying for Ferrying Command. This is one of the planes that carried the Harriman Mission to Moscow in September, 1941.
- A news clip with photo, "New Atlantic Speed Record Established," shows an RAF Liberator I (short nose) in flight, seen from 2 o'clock high.
- A photo shows B-24Ds on the production line. Because this photo was taken before Willow Run came on line and shows a different floor layout from the Fort Worth plant, it is most likely the San Diego plant.
- A news clip with photo, "In air 100 days ahead of schedule," shows a B-24D on runway, seen from 11 o'clock.
Joe Baugher's list shows all of the early B-24Ds from Fort Worth as being delivered as Liberator IIIs; the photo does not show camoflage paint or insignia and the tail number is not legible. It is certainly a B-24D, though.
- "B-24s in Quantity Production" [ HTML ] includes 14 detail photos of B-24s on the San Diego assembly line.
- A Bassick Casters ad, "Great Bombers on Little Casters Grow!," shows caster-equipped carts and fixtures in use at Consolidated. One plane is a B-24A (round engine nacelles), seen from in front of the inboard left engine nacelle.
- A Flex-O-Tube ad, "Ford-built Bomber O-1," a B-24E-1-FO, on hardstand, seen from ahead of the outboard left engine nacelle.
- A photo taken from a Rohm & Haas ad shows the nose of an early B-24 seen from 2 o'clock. Plane is in bare-metal finish, has non-turbocharged engines and short nose.
- A Wyman-Gordon (forgings) ad shows a Liberator I in flight, seen from 2 o'clock high.
- "Ferry Command" [ HTML ] includes a photo: "Being flown across in large numbers, and also used as an ocean transport, is the Consolidated Liberator (B-24)."; view is from 6 o'clock high.
- A Solar Aircraft Co (exhaust systems) ad shows a Liberator I from 11 o'clock high. The plane has what appear to be hand-drawn stars in place of the RAF roundels.
- A news clip with photos, "Today's Cargo Planes Now," shows a C-87 in hardstand, seen from 2 o-clock, and a C-54 on the production line, also seen from 2 o'clock.
- A Consolidated Aircraft Corp ad, "'Guns' that shoot 3000 miles !," shows B-24Ds on the production line at San Diego.
- A Consolidated ad in the "Consolidated builds Battleships of the Air" series shows a B-24D on hardstand with maintenance trainees standing on the wings, seen from 10 o'clock. Plane has star-in-circle insigne. 51 men are visible in the photo.
- A Roller Bearing Co of America ad, "Mission accomplished
," shows B-24D-CO 111717 from 10 o'clock high. Plane has two-gun tail turret.
- A Consolidated ad in the "Consolidated builds Battleships of the Air" series, "Sky Truckers," shows C-87-CF 111639 in flight, seen from 10 o'clock low.
- A Bendix ad, "Building Land Legs for Battleships of the Air
," has a publicity photo of an early B-24, probably a -D, with people standing on the wing. View is from the ground below and ahead of the left wing tip. Photo show 29 men on the left wing and the heads of two more apparently on the right wing. Plane has star-in-circle insigne. The ad includes an inset showing the right landing gear, seen from behind and outboard.
- A news clip photo, "Double Action," shows B-24s and C-87s being assembled on the same production floor, illustrating "Single Assembly Line Produces Both Bombers and Transports" [ HTML ]. Foreground planes are probably B-24D-CFs. Second B-24 has liferaft doors open.
- "Single Assembly Line Produces Both Bombers and Transports" [ HTML ] includes 24 photos showing details of the construction of B-24 and C-87 planes, with a final photo of a C87 on the flightline, seen from 2 o'clock, with nacelle panels removed.
- A captioned photo, "Famed B-24 Liberator .
," shows a B-24D in flight, seen from 11 o'clock high.
Plane has 9-and-3-o'clock-position "rams-horn" pitot tubes, horizontal.
- A photo taken from a Wittek (hose clamps) ad shows a B-24C or early -D in flight seen from the typical 2 o'clock high. Plane has "meatball" insignia.
Plane has single-gun nose, no astrodome, horizontal "rams-horn" pitot tubes.
- "American Colossi" is a color Gallery photo of a B-24 flying over the Grand Canyon. Plane has star-in-circle insignia, is seen from 3 o'clock.
- A news clip with photo, "Outdoor assembly line," shows B-24D-80-CO planes being worked on on hardstand in Tucson, AZ. Plane 240638 is in the foreground.
Tucson was a modification center. Three large hangars were under construction when the report was made.
- A Presstite (sealing compounds) ad, "[Consolidated Vultee aircraft] Are sealed with Presstite sealers," shows B-24D-13-CO 123928 in flight, seen from 4 o'clock high. Nose and tail armament appear to be dodged out.
- A Bendix Aviation (hydraulic controls) ad, "Clockwork," shows a B-24 from 10 o'clock high.
The photo shows a plane with long nose and B-24D armament but with B-24A non-turbocharged engine nacelles.
- "Marine Might" is a four-photo spread that includes a shot of B-24D-7-CO 123827 in flight, seen from 10 o;clock low. Plane is in OD-over-grey, has star-in-circle insigne.
- "Liberators by Consolidated Vultee" [ HTML ] includes 13 photos of subassemblies and/or planes on the assembly line, including 2 photos of finished planes:
- B-24D or -E in flight, seen from 8 o'clock low [ photo ]
- B-24E-20-CF 129054 on flight line, seen from 5 o'clock.[ photo ]
- "Liberators by Ford" [ HTML ] includes 13 photos of machinery, components, subassemblies and planes on the Willow Run assembly line and 5 drawings of assembly fixtures.
- A photo from a Standard Pressed Steel (Unbrako cap screws) a, shows four B-24Ds flying in formation; Foreground plane seen from 10 o'clock low.
These planes appear to have the Sperry ball turret installed, shown fully retracted.
- A captioned photo, "Eager Beaver will fly this one-ton bomb to Germany.", shows ground crew working on a bomb in front of the three-gun nose of B-24D-CO 111600 Eager Beaver.
- A news clip photo shows battle damage to the three-gun nose of a B-24D.
- A Rohr Aircraft Corp ad, "1200 horses get ready to fly!," shows right-hand engines and nose of a B-24D on the flightline, along with small detail photos of the nacelles and an engine.
- A Triplett & Barton (testing services) ad, "Tough Guy," shows B-24D-13-CO 123928 in flight, seen from 4 o'clock high.
- "How Fewer Build More Bomber Nose Sections" [ HTML ] includes 15 photos showing details of subassemblies and fixtures involved in producing the nose section.
- A Harry Ferguson (Ford-Ferguson tractors, Ford Moto-Tug) ad, "Saving time and man power on flying fields," has three photos of flightline tugs with B-24Ds (at Willow Run), along with a couple of photos of farm tractors.
Featured plane ("05" on nose) has three-gun nose and "rams-horn" pitot tubes in 10-and-2 positions, angled.
- A two-page Rohm & Haas ad, "Plexiglas on the Consolidated B-24," has a photo of a B-24D, seen from 4 o'clock high, and four detail photos of tail turret, top turret, cockpit and greenhouse.
- A news clip with photo, "On the nose to win," shows a detail photo of an Emerson turret on the nose of a B-24E or -J.
- A Scovill Manufacturing Co (LOXiT skin fasteners) ad, "Test it
," shows B-24D-13-CO 123928 in flight, seen from 4 o'clock high and a photo of B-24Ds on the production line. Photo is probably from San Diego plant. Plane in foreground shows inner engines, cockpit glazing and top of fuselage most of the way back.
- The color front cover of the Flying "Special Issue US Army Air Forces At War" shows B-24Ds on the flightline.
Foreground plane is a detail photo of the Consolidated tail turret. Midground plane is B-24D-1-CF 263764. This plane is elsewhere listed as a B-24E-25-CF, a "tunnel gun plane."
Planes have tunnel-gun windows with no evidence of ball turret installation; noses seem to be three-gun versions.
The photo looks to be at the Fort Worth plant, which would make all the visible planes probably elements of the same contract and hence part of a small serial-number block.
- A color Gallery photo, "Consolidated Liberator, fighting on every front, is being supplied in large numbers," shows a B-24D in flight over water, seen from 2 o'clock high.
- A color Gallery photo, "One of a Liberator's .50-caliber waist guns," shows a young man, probably a scout, at the left waist gun station of a B-24 (probably a -D.) Noteworthy is that the structure is in natural metal, with the support and pintle for the gun in yellow chromate. The gunner is wearing a campaign hat, headphones, leather flight jacket and khakis; no gloves, no heated flight gear. And he looks really young.
- A color Gallery page has two photos:
- "Jap shipping and bases in the Aleutians get special attention from these Liberators. Note unusually good weather." shows B-24D-CO 111773 on the ground, seen from 2 o'clock. Plane has bomb bay doors open, appears to have a three-gun nose.
- "Crew of one of the Libs above is briefed by its pilot. The objective is Kiska; pilot is showing approach to target." shows flight crew of 9 alongside the nose of a B-24D.
- A Gallery photo, "Hell's Belle," shows B-24D-145-CO 241183 in flight, seen from 10 o'clock low. Original photo was Duotone in blue.
- A Gallery photo, "Liberator Formation," shows three B-24Ds in formation, seen from 4 o'clock high. Planes have two tail guns, hence turret; no deployment of belly turrets.
- A Gallery photo, "Bogged down," shows the left main gear of a B-24 buried rim-deep in mud. Good detail photo of main gear. Bomb bay doors are open; flaps are deployed.
- A White-Rodgers Electric Co (temperature controllers) ad, "Make them more and more automatic," shows shows B-24D-13-CO 123928 in flight, seen from 5 o'clock. This photo shows that the plane had the single machine gun at the tail station, without turret.
- "Piloting Big Bombers Is Big Business" [ HTML ] includes 3 photos:
- B-24E-1-DT 128415 from 7 o'clock high [ photo ]
- pilot and copilot in B-24 cockpit, seen from behind [ photo ]
- pilot standing below #3 nacelle; bomb bay doors open [ photo ]
- A Delco Radio ad, "No Place Like Home," shows three B-24Ds in formation. Foreground plane is seen from 10 o'clock high. Planes have star-and-bar-with-outline insignia.
- Detail photo from a Rohm & Haas ad shows an Emerson nose turret.
- An American Chemical Paint Co (metal prep and paint) ad, "to Speed Finishing," shows B-24H-1-CF 264435 from 2 o'clock high.
Plane has Emerson nose turret.
- A Saginaw Products Corp (bomb trailers) ad, "Tonight we bomb Berlin," shows a B-24D on hardstand from 7 o'clock with loaded bomb trailers in the foreground. Plane appears to have Sperry belly turret; has "meatball" insigne.
- A Kropps Forge ad, "Enforcing the Law of Retribution," shows a B-24D in flight, seen from 10 o'clock high. Plane has star-in-circle insignia.
Guns (except for top turret) and tail number are dodged out. A small blip behind the wing, on the lower fuselage, looks to be a Bendix remote-sighted turret.
- An Emerson Electric ad, "Emerson-Electric Builds New Offensive Power for the Air Offensive," shows B-24H-1-CF 264435 (listed in another source as a B-24E-25-CF) in flight, seen from 2 o'clock high, and a detail photo of the nose turret. Plane has star-and-bar insignia.
The plane appears to have tunnel-gun sighting windows on the lower aft fuselage. It is listed as one of the tunnel-gun B-24E planes, built in Fort Worth from a Willow Run kit.
- A Borg-Warner ad, "Curing "Charlie Horse" in warplanes
," shows a B-24H or -J in flight, seen from 2 o'clock high.
- An American Chemical Paint Co ad, "Chemcially Clean Surfaces for Lasting Metal Finishes," shows a B-24E or -H in flight, seen from 2 o'clock high.
Plane has Emerson nose turret, tunnel-gun windows.
- A Wittek Manufacturing (hose clamps) ad, "Teamwork for Victory," shows B-24H-1-FO 27614 in flight, seen from 10 o'clock low. Plane has star-and-bar-with-red-outline insigne.
- A Wolfe & Mann Manufacturing (work stands) ad, "New! Airborne Service & Repair," features a drawing of a crew on a workstand, working on #4 engine of a C-87 while another crew load a knocked-down workstand into a cargo door in the plane. It also includes an inset of a workstand knocked down for shipment.
- A four-page United States Rubber Co ad includes a number of detail photos of B-24Ds:
- "19,000 pounds more load on lighter, stronger tires" shows a closeup photo of the left main gear, seen from ahead and outboard with rear fuselage in the background. This photo puts to rest any arguments about "bulged" tires on landing gear.
- "Here comes 60,000 pounds of bomber!" shows a B-24D on final approach, with gear down and flaps deployed. View is from 1 o'clock low.
- "Increased 19,000 pounds since 1940":
- "More Guns!" is a detail photo of the tail turret
- "More Bombs!" shows bombs being offloaded from a bomb trolley at the left side of the plane
- "More Fuel!" shows B-24Ds flying in formation. Foreground plane seen from 10 o'clock low.
- "More Power!" shows the engines on the left wing
- "From flying boots to fuel cells
from boats to block tread tires":
The 19,000 pound increase is in comparison to the XB-24.
- "Flying Boots" is a detail photo of fleece-lined flight boots
- "Lifesaving Boats" shows a life raft, with 4 crew and with sail rigged
- "Fuel Hose" is a detail photo of self-sealing hose being penetrated by a bullet
- "Fuel Cells" shows workers installing a self-sealing fuel cell into a plane's wing
- "US Royal Airplane Tires" is a detail photo of the treads of two airplane tires
- A US Hammered Piston Rings ad, "The Power to Persuade Peace," features a color photo taken from under the end of the left wing of a B-24D, showing left engine nacelles and the left side of the nose.
- A photo taken from a Harry Ferguson, Inc, ad (Ford-Ferguson "Moto-Tug") shows a B-24D in tow by a flightline tractor, connected by a tow bar to the towing lug on the front landing gear. Photo shows details of the nose and the inboard right engine nacelle.
- A photo from a Socony-Vacuum (Mobilgas aviation fuel) ad shows C-87-CF 330566 being loaded on a grass field. View shows aft left fuselage, cargo door, and empennage.
- A Barber-Colman (cabin heating) ad shows a B-24J in flight, seen from 10 o'clock high. The photo shows the Sperry ball turret; this plane should have the Consolidated A-6 nose turret. From the nearly-legible tail number, this should be a B-24J-25-CO or B-24J-30-CO.
- "Landing puddles or airports" includes a photo of B-24J-25-CO 273250 in flight, seen from 3 o'clock.
- A Schatz Manufacturing Co (ball bearings) ad shows a B-24J from 10 o'clock high.
The nose turret seems to be a Consolidated design, which makes the plane a -J.
- Photos from a Whiting Corp (propeller positioner) ad shows some details of a propeller positioner, which allows one man to handle, transport, align and mount a propeller.
- A Houdaille-Hershey Corp (dampers) ad, "Houdaille Knows Hydraulics," features a detail photo of the nose-wheel shimmy damper on the nose landing gear, superimposed on a drawing of a generic B-24.
- A Barco Manufacturing (flexible hydraulic joints) ad, "Vital links in a bomber's "plumbing"," shows a PB4Y-1 from 10 o'clock high.
- A Solar Aircraft Co (exhaust manifolds) ad, "200,000th Manifold on its way to Victory!", shows a 14-cylinder exhaust manifold with a reduced-contrast B-24D (11 o'clock high) superimposed on it.
- A Gallery photo, "South Pacific Search," shows a B-24J in flight over jungle, seen from 2 o'clock high.
- A Barber-Colman Co (fractional-horsepower motors and thermostats) ad, "Barber-Colman Controls for a uniform cabin temperature in Navy-type Liberator," shows a PB4Y-1 with ERCO nose turret and what is probably a SCR-717 radar in the ventral turret position. View is froom 11 o'clock low.
- Photo of workers installing soundproofing on a C-87.
- A Dumore Co (fractional-horsepower motors) ad, "Dumore's ammunition booster motor A1B1PL," features a photo of the motor and a detail photo of the ammunition-belt drive sprockets in the top turret of a B-24.
- A Flex-O-Tube ad, "Flex-o-tubes in the nose of the B-24," has a detail photo of the hydraulics of the Consolidated nose turret on a B-24J.
- "Convair Produces RY-3 Military Transport" [ HTML ] includes 2 photos:
- A US Hammered Piston Ring Co ad, "Scourge of the Sky," features a color photo of a PB4Y-2 Privateer in flight with coastline in the background; view is from 9 o'clock high. Plane has nose number of E56; tail number is not quite legible.
- A Torrington Needle Bearings ad shows a B-24J from 11 o'clock high and a drawing of a rudder pedal segment. Nose, tail and waist guns have been dodged out.
- A color Gallery photo shows the tail area of a B-24 with German markings, captioned "This captured Liberator was flown by Germans, recaptured by Americans." If the number stenciled on the visible tail is associated with the airframe, it is consistent with it being a B-24D-1-CO (123641). Tail turret installation appears to be consistent with a B-24D.