The Ruptured Duck B-25 Swappable

On April 18th, 1942 at 8:20 AM Pacific time. Sixteen U.S. Army Air Forces B-25B Mitchell medium bombers were launched without fighter escort from the U.S. Navy's aircraft carrier USS Hornet deep in the western Pacific Ocean, each with a crew of five men. The plan called for them to bomb military targets in Japan and continue westward to land in China. Though it never returned from the mission, one became the most famous of all. Flown by Lt. Ted W. Lawson who authered the book "Thirty seconds over Tokyo" Out of fuel, and short of the China mainland "The Ruptured Duck" was ditched off the tiny Island of Nantien. The wreckage was later salvaged by the Japanese and put on display in Tokyo.

In honor of the brave men who flew the Doolittle raid on Tokyo.

I present to you!

"The Ruptured Duck B-25 Swappable

Designed around the same power system as the FT Cruiser this aircraft has been a real pleasure to design and build . It weighs in at about 48 oz and somehow balanced right off the building board. Wing span is 60"  Length is 46", and wing area is 493 Sq. " giving it a wing loading of 14 oz per sq foot. It requires seven sheets of Adams Ready Board and one sheet of poster board and about a quarter sheet of Owens pink Foamular to build. Variable thrust is used for yaw control as the twin virtical fins made it difficult to ad rudder controls. It even has a bomb bay that can be used to drop ordinance such as jelly beans or somehing. LOL Let's take a look at the build!

The fuselage parts are cut and ready to assemble!

The battery box and nose deck are first. Formers are added as you progress

The bomb by is framed by formers F-4 through F-6

The two sections are then attached.

The tail is then assembled using the keel, Stabilizer mounting plate, and formers.

F-7,8, and 9 are split to acomidate the horizontal brace.

The tail is then glued to the forward section of the fuselage.

I used a Du-Bro 1/2 A steerable nose gear, but had to make the strut from 3MM piano wire as the one that came with the unit was too short.

The servo and gear are then connected and zeroed.

The belly is cut from one piece and paper is stripped from certain portions to allow it to be curved to match the fuselage frame. The bomb bay doors and nose gear hatch are cut also though it's hard to see in this photo.

Marking the location of the bomb bay on the belly ensures propr alignment of the belly.

The belly being glued on.

The foam curves quite well to match the formers.

Just a slight trim to even things up.

Nice and smooth.

This was the original Idea. Later modification for the canopy to be used as the battery box covor became a nessesity.

Music wire is used to strengthen the elevtors.

Virtical fins are then added.

This is the lower tail sheeting. Notice the paper has been removed in strips so that it can be curved to fit the frame.

Like this.

The upper tail sheeting is done in the same fashon.

All the sheeting and tail glued in place.

Curving the wing center section.

The main spar, and dihedral braces are then added.

The wing center section completed.

The wing is built pretty much standard to my other designs with the adition of the main gear supports made from 18" Ply. Note the slots for mounting the engine macelles and the hole for battery lead and ESC wiring.

I tried using a piece of chord to guide the wiring after the wing was folded, but the chanel was too narrow and the connectors caught on the LG plates. I recomend laying a piece of tape ofer the plates to eliminate the edges. I eventually used a piece of 1MM piano wire to pull the wiring through.

The wing halves are then butt glued to the center section and the main spar before folding.

The inboard section of the wing is folded over and glued in place. Note the slots in the center section of the wing. these are for the fuselage mid section to be mounted in.The outboard section folds seperately to allow the anhedral bend just outboard of the engine necelle.

The right wing is completed and ready to build the left wing.

The completed wing. Only the servo leads are in place at this time.

Only the inboard section of the wing has a 6 degree dihedral. the outboard section is level to the airframe.

One inch spacers are used to ensure proper angle of the wing. My building table isn't long enough to allow braces at th tips of the wings, but one inch braces are also used at the outer end of the lower surface of the wing. This ensures that the outer end of the wing is level.

Aileron connections are then made.

The Y connectors for the battery lead are then prepared as per the FT Cruiser set up video. Wire length is 50" total or 25" per half to allow the strech from engine nacelle to battery box.

ECS and battery leads all in place.

Note the slots in the lower surface of the center section. These are for the wing mounting plates.

The only modification to the standard FT power pod is the addition of down thrust and right thrus, and I also use my firewall. It allows the guide holes to be set lower that the FT version I've hade some trouble with the holes taring out. I also laminate two 1/16" firewals with the grain in opposite directions to provide extra strength.

The engine nacelles are then cut and folded in a B type fold. The built in mounting tabs make it a little dificult to fold it initially, but with a little patience they work well.

Removing the paper from the inboard surface of the gear doors and aft section of the nacelle allows the foam board to be curved.

I've been using a section of 1" PVC pipe for this. works quite well.

Once all the curves are made as such it's time to fit the power pods.

As I mentioned earlier, I provide a pod mounting plate that allows the guide pin holes to be lowered. It seems to work quite well.

Making the guide pin holes.

Both nacelles ae ready to fold at this point.

The nacelles must be folded while laying on their sides due to the mounting tabs.

The nacelle formers are cut and ready to mount.

N-1 is mounted flush with the front of the nacelle. Note the gap at the top. this provides clearance for the power pod to be mounted.

N-2B is then mounted in the slots provided.

N-3A in place Note on both sides.

N-3B is then slid in place under the ger doors.

Making sure it is aligned with N-3A before gluing.

LG-1 throught 3 are layered in front of N-3B to provide a slot for the LG mounting rod. he main gear is mounted in the same fashon at the FT Cruiser.

The mounting rod is then glued securely in place.

The power pod is then inserted, and the tale of the nacelle is centered, glued, and sanded smooth.

N-2A and the side braces are then glued in place.

Both nacelles completed and redy to be mounted.

Main gear is bent to shape from 3MM piano wire and ready to be mounted.

Preparig the slots for the main gear in the lower surface of the wing.

Guideing the wiring harnes to mount the nacelle.

Gluing the main gear in place.

The nacelle and gear in place. ready to secure the gear to the nacelle.

This is also done in the same fashon as the FT Cruiser.

Minor adjustments to the angle of the gear can be made at this point.

The cowling is created by printing the template directly in the poster board. The template is 8 1/2 X 14. I simply cut the PB to leagal size and printed. The cooling fins are in the same print. Cut and glued in place to give a three dimensional look.

I fit the piece as closely as possable and marked for gluing.

Marked the lower end of the cooling fins to trim off the excess for a better fit.

Worked great!

The rear nacelle sheeting cut and ready to mount. Note the notch cut in one side to allow for the LG.  It's marked on both sides for left or right nacelle, but you only need to cut one for either side.This is mounted in tha same fashon as the cowling on the 190 making sure to provide for the pod mounting skwewer as you attatch the skin so the holes line up.

Nose rings cut from pink foamular mounted and readyfor sanding. Note the wing mounting plates are also mounted to the center section of the wing. Also the battery and ESC leadsdan be accessed from the LG bays.

I used DAP Fast and final Spackling to fill and sand

The wing is glued in place, and ready to run the wiring harness to the battery box.

I chose to glue the wing in place. However they may be mounted by adding BBQ Skewers through the fuselage skin, and wing mounting plates and securing with rubber bands. This will make it easier for transport. Also notice the bomb bay doors. There is ample room in the bomb bay for  a droppable payload.

The fuselage center section cut and curved for mounting. Note the foam is removed fromthe front and rear edges to overlap and glue to the fuselage unless you chose to make the wings removble.

It is first glued ito the slots in one side of the wng, and is still flexable enough to insert into the slots in the other side.

Pink foamular blocks are then added to the tale of the nacelles to finish them off.

Now for the nose canopy and cockpit. I've decided at this point to modify the design to better incorpirate a removable cockpit as the battery box covor.

This is the original nose canopy fame with the windows removed to laminate for a clear enclosure. It has since been modified to fit a .30 cal. mounted in the nose frame. I had to design it in three sections as you see in the above photo. laminate first and then cut from the template.

The side windows are first glued under the center piec as shown and work your way up one side using the tabs to glue the structure together.

This is the result! I recomend printing the fram on standard printer paper as cardstock or poster board makes the frame too ridged to bend and glue. I'm still working on a better adhesave to use for this process. as Super glue can fog the glass, and hit glue is really messy, and the triple didget wether we have been having lately has wreeked Havoc on all the hot glue joints in this project. Fortunately my first venture out with the Duck was for photos and not for a test flight. Unfortunately I won't be able to get a flight in anytime soon because of the heat.

The cockpit is one piece and much easier to fold, and glue. This is where the modification had to be addressed though.

This is the battery box cover sheet that resulted.

The tabs at the sides are folded and glued like the power pod and paper removed so it could be curld to match the fuselage. Rare earth magnets should be used to place in the tabs to secure the cover.

The covert plate is then glued at a 90 degree angle on the rear support pate centered on the support tab on the rear plate. The slots to the side of this are for the battery box to slide up into when munting.

The battery cover is painted prior to mounting the canopy and the canopy should hange out about a 1/4" past the rear support plate to fit over the fiselage.

I had to cut away the section of fuselag to fit the cover on, but the plans now reflect the proper modifications and it will be fully explained in the build module on my FB page and in the instructions.

The .50 cal is made from a piece of 1/2" X 1/4" hardwood dowl and a BBQ skewer

Looks pretty good after it's mounted.

A 27.3 oz bottle of smartwater from Wal Mart was chosen as the gun turret. Thanks to Jose Valentine for the effort in helping with this.

A 1 1/2" section was removed from the bottom of the bottle, and the vry bottom of the bottle ws removed. Residue from the lable was removed easily with Isopropal Alcohol.

The template for the turret top and the bottom plate are the same. The inner ring is cut out, and then laminated.

The same ring is then cut from the laminate to form the top of the turret.

And super glued in place.

The outer ring of the template is used to make the turret base.

It should fit snugly inside the turret.

A template is provided for the slots for the gun barrols.

It doesn't matter where you place it just as long as the bottom surface is flush.

The .50 cals are made the same as the nose gun.

Ready to be painted.

Now to paint the framework and mount to the fuselage.

I painted the entire aircraft Olive drab, and printed the decals!

More .50 cals in the tail. That's a block of foamular sanded to shape and BBQ skewers added.

This was actually quit simple for this design. Clear printable decal sheets are available from Decalpaper.com at this addrss www.decalpper.com/product-p/tryc.htm they have a wide selection of waterslide decal sheets available.

I chose to just print mine on standard printer paper, and dilutedsome elmers white glue with water. Brushed it on the back of the decals and applied to the model. they can be then covered with clear spray laqure. It works quite well.

Now to mount the turret, props and secure the wheels, and get some pics!

The turret turned out ok. LOL just didn't mix enough paint to really finish the framework.

She still looks pretty good though!

As I mentioned earlier the 40 minutes or so I spent getting these photos in triple didget heat just let me know that caution should be taken in extreme heat when using hot glue on these things. Be sure and check your glue joints in this kind of weather.

In all this has been a blast to design, and build! Thanks goes to FT and lazerToyz for having the electronics package available for this design, and the set up video for it's instaltion. Thanks also goes to Jose Valentine and Randy Floyd for thier support, and encouragement.  Feel free to visit my FB page for the full build module, and plans will be available at my website by August 15th hopefully. Unfortunately I will be moving at the end of the month, so I'm not sure if I can get repaires done from the melt down (LOL) and get a test flight done before the move. I'm moving to Va to be closer to my grand kids, and my son who is in the Navy is finally interested in model aviation, and wants to help with my designs also. 

There may just be hope for him yet. LOL

 I just got word that Randy floyd has had his maiden with the "Duck" It went well but the wings flexed pretty bad at the end. I've already made the modification to add Ply. dihedral braces in place of the original foam ones! If you have already received a copy and it doesn't indicate the Ply. Braces. Please contact me for the upgrade! Here's the you tube video of the maiden! Great work Randy!

Enjoy!

[video='http://youtu.be/ATfskK9xKkQ']

Visit my website and get yours today: "The Ruptured Duck"

View the build module here: "The Rupturd Duck" build module