B-47 1/10.2th Scale, Boeing Stratojet...In The Beginning

[Flite-Metal]

Considering the B-47's flaps are literally hung out there like sheets on a clothes line to dry in a tornado... I have been more than a
little concerned about oscillation due to accumulative slip tolerance. Only after Sam's flap model is constructed with c/f tubes,
sheeted flap, base with side foils and servo to drive it all can we go road test it...Yes, road test it on the Westpark Toll Road.

My suggestion we try dual channels did not pan out. Sam is marching on with his current C/F tube game plan.

Sam made an interesting observation...our effort to simplify the flap mechanism to reduce potential binding brings
us closer and closer to the 1:1 flap hangers and screw jack locations.

With our reduced flap footprint we can now utilize the scale 1:1 rear spar location...

[Flite-Metal]

I will continue to place this Boeing dims drawing on each new thread page from here on out as an index. Clicking the drawing
will enlarge it if you want to copy paste it for your reference if building along with us.

[Hustler58]

Ed have you found any drawings or pictures of how the flaps work? Are they like the B-52? Thanks Butch

[Flite-Metal]

Butch,

There are hangars across the top of the leading edge which have their pivot point behind the leading edge just beyond the
close of the elipse. At 10.2% its impossible to provide proper strength using the 1:1 method.



Hangars allow travel along five/six narrow tracks distributed across the bottom of inboard and outboard wing sheath
above the flaps themselves. Its a shallow Fowler due to the technology at the time didn't permit alloys capable of
carrying a load of more than about 30 degrees. I have observed five hangers....Darius shows six on his model.



Sam has completely reworked the inboard flap mockup. I will post photos shortly. The next thing is the mockup is mounted
beneath a plywood piece across the hood of my truck. I will drive down West Park Toll Way and operate the flaps at specific
speeds to observe flutter.



In the above photo of Darius' Sanger B-47 the depression on the top surface of each flap is exaggerated...IMHO when it
is compared to the close up photo I have show of this surface.

Sanger's 48th V-form constructed and customized by Darius Aibara...images from Sanger's web site foir his promotion. His
kit does not include flaps. This assembled B-47 is the result of his customer's fabulous alteration to Sanger's nice size kit.



The flaps are the most critical element of the B-47....just as they are on the B-52. I anticiapte approaches at 50 mph sustained to around
30 mph coming across the headend of runway.

I posted some images of 1:1 flaps at speed and down during final. Our flaps are not down more than about 20 degrees...plus 6 degrees of
incidence for a total of 26 degrees. Below you can see the hangars on Darius's build of Sanger's 48th vacuum formed B-47.



Hangars are in pairs L & R of roller axle... There are other wing sheath supports similar in shape to the hangers as seen in the
photo I posted showing the wings standing on end during assembly...observed from their root end.



Below is the pattern Darius made for cutting his hangers. The cantilever triangle IMHO if replicated in functionality would simply
be complicating the issue. These are faux pieces beneath the sheath and over the top of the flaps. We have plenty of depth.

[Flite-Metal]

Here you can see the hangers over the flap bay. I have pilot and crew manuals...no assembly manuals. I have never seen assembly
and service manuals available for the B-47.

[Hircflyer]

Originally Posted by Flite-Metal

Here you can see the hangers over the flap bay. I have pilot and crew manuals...no assembly manuals.
I have never seen assembly/service manuals available for the B-47.

Flaps were on carriages with four rollers which ran on track which caused the flap segment to go back and down. I am sure you are aware the outboad segment worked in conjunction with the aileron, acted as a flaperon. Flap spilled withup aileron. Do not remember the amount.

[Flite-Metal]

Yes, the 1:1 used rollers on the hangers running in overhead narrow channels beneath the wing sheath.

You can clearly see depression rectangle on top surface of the flaps is gradual and begins roughly 25% back from the leading edge.
Pivot point for flap is high and terminated above flap surface.

For obvious reasons this is "not" being replicated... Sam's and my opinion to attempt to replicate this on a model would involve
twenty cantilevered tracks requiring perfect alignment of no fewer than 40 roller bearings. Its NOT that it can't be done... ;^)

There is no reason to replicate this vulnerable mechanical movement at 10.2% when the hangers can be simulated beneath the
wing sheath. However, the screwjack is simulated by carbon fiber tube movement. Below is Sam's original flap workup, this has
changed except for the 26 angle and rear most position.

The "outboard" flaps move in differential aileron with the ailerons to a maximum of 20% of deployment rearward..."up to about
175 mph on the 1:1". This effectively increased aileron surface area attempting to compensate for the fact the flow envelope
across the wing at the ailerons closed "behind" the aileron trailing edge...delaminated from the wing.

This resulted in crashes...during takeoff and landing of early B-47's until two rows of turbulators were epoxied to the surface of
the wing ahead of the ailerons. This abruptly broke the flow down and it came across the top surface of the ailerons.

All of this has been shown previously in this thread. Such is the issue with a build thread of this size . I have some technical
~maintenance information from an Italian source...of all places . I suppose the Italians paid a little more attention to what
they knew was constantly overhead.

I would have imagined after declassification someone would have copied a set of maintenance manuals like the pilot and crew
manual...though it would be in many volumes. I wonder if one of the B-47 Association members has a "set" of maintenance
manuals they would be willing to let be used as a reference.. ;^)

[Flite-Metal]

I was grooming my LABS documentation early today and found a January 1956 focus in Popular Science for a couple of pages beginning
on page 136 with photos. It would be nice if it could be converted to hardcopy. Here's the address if you would like to view:

http://books.google.com/books?id=4iUDAAAAMBAJ&lpg=PA136&ots=vt2PzMCfVH&dq= B-47%20Flap&pg=PA136#v=onepage&q=B-47%20Flap&f=false

[Flite-Metal]

What we have here is a failure to find a domestic... Well kinda sorta...on the right is Stu's 89mm cut down 100mm tractor.... 89mm
makes 10# static. Quads...to the rescue. Looking for flying footage.

[Flite-Metal]

The original brass tube flap drive is compared to the carbon fiber tube replacement to illustrate the reduction in footprint within our wing.

Below are the carbon fiber tube components with two 2-56 all thead rod inserts for attachment to Nyrod in wing.

Nested telescoptic carbon fiber tubes and rods.

Total flap mechanics footprint is now five (5) inches.

[Flite-Metal]

With Dave expressing frustration with not finding definitive airfoils and Sam and I working on inboard flap, outboard flaperon, and
the ailerons it was time to post our BAC145 @ 6 deg. I show the Boeing provided CG location of 25% MAC.

I will build upon this post to show flap travel...stay tuned.

[Flite-Metal]

Here it be...

Comments, questions, exceptions, and contributions welcome!

Like I've made reference to...things are skinny out there since BAC closed the door and threw away the key. I look forward to MGST
Thomas Kaye's return from Omaha, NE after attending the B-47 Association reunion next weekend.

[Flite-Metal]

Two (2) nyrod driven C/F teletubes, five (5) C/F teletube sections per inboard flap. Remember nothing else changed from the
original configuration shown earlier in this thread. Outboard flaps are a completely different design because they are flaperons.

The drawing below is not an engineered drawing...it is for visualization only. Photos of the actual redesign will be posted after
I receive the mockup from Sam at our club meeting Sunday.

[Flite-Metal]

And then there were resources...

[Voyager2lcats]

Ed, not trying to interrupt your flow here (pun intended), but your animated flap drawing is very nice. Fantastic details here- really enjoying your thread.

Bob

[TDisaster]

Originally Posted by Voyager2lcats

Fantastic details here- really enjoying your thread.

Bob

Agreed!

[Flite-Metal]

Hi Guys,

Its finally time to audit the Boeing drawing against all our collected documentation to arrive at our final dims. Earlier today it
was interesting to see assumptions made from earlier drawings were not that far off from what our final dims are. Literally
everything is being sized width, height, and length.

This is where the rubber meets the road...everything moves from what could be to what is... For example our wingspan is
139.06149 inches at 10.2% of the 1:1.

I will share the baseline wing and fuse.

On the right is a segment of my documentation multiple view drawing. It is a measured and engineered Boeing Aircraft Company
(BAC) drawing of the B-47"E".

On the left is a Boeing Corporate artist "rendering" of the B-47A general layout showing a 25% of MAC CG declaration and other
sweep data. This is consistant with the CG on the Tu-95 CG location.

The drawing on the right does not have dims. The declared dims from the left drawing are applied to the right drawing which has
thinner (tighter more accurate images). This is an audit of the right drawing based on the declared width of the wing tank.

This time consuming task will define our entire airframe dims....that's each and every component comprising a 10.2% B-47E-IV.
We move from gathering documentation to applying documentation.

[Flite-Metal]

Something I had failed to pick up on until this afternoon during a conversation with Sam. There is a 5 deg 45' diflection illustrated
on the Boeing artist rendering...but it does not appear on the engineered drawing. This had me going for a while until Sam reminded
me the outriggers on the 1:1 are free castering...with lock out during touch down. Top image illlustrates the extension of the mains
prior to touch down.

Its that 5 deg 45' offset from the vertical that doesn't jump out at you when you review this drawing. The outrigger strut sits with
a 5 deg 45 minute slant back to assure its free castering stays in a trailing position during touchdown and taxiing. On my B-47 the
1:1 castering feature will" not be replicated". Weight distribution is an issue to begin with. I don't dare chance outrigger vibration.

[Hircflyer]

Originally Posted by Flite-Metal

Something I had failed to pick up on until this afternoon during a conversation with Sam. There is a 5 deg 45' diflection illustrated
on the Boeing artist rendering...but it does not appear on the engineered drawing. This had me going for a while until Sam reminded
me the outriggers on the 1:1 are free castering...with lock out during touch down. Top image illlustrates the extension of the mains
prior to touch down.

Its that 5 deg 45' offset from the vertical that doesn't jump out at you when you review this drawing. The outrigger strut sits with
a 5 deg 45 minute slant back to assure its free castering stays in a trailing position during touchdown and taxiing. On my B-47 the
1:1 castering feature will" not be replicated". Weight distribution is an issue to begin with. I don't dare chance outrigger vibration.

Hate to differ with your source, but outrigger gear did not free caster it had torque link on the strut which had to be disconnected for towing....OR what happened on sharp turn in and out of hanger etc....or backing up, they broke! The torque link kept the tire from rotating side to side and wore out a lot we replaced them fequently.

You can see the link in picture in thread 355

[Flite-Metal]

Interesting... One need only watch Strategic Air Command, the movie to observe the out riggers castering when the B-47's are
viewed up close when turning onto the runway for takeoff.

YouTube Video

[Hircflyer]

Originally Posted by Flite-Metal

Interesting... One need only watch Strategic Air Command, the movie to observe the out riggers castering when the B-47's are
viewed up close when turning onto the runway for takeoff.

YouTube Video

The B47 had a large turning radius....the Fwd main gear had a max turning of 20 deg left right and the rear main was fixed which made for a wide radius....the outrigger wheel(s)during normal taxi remained in the fixed position held in place by the torque links... there was no way crew could lock and unlock the outrigger wheels from the cockpit...when towing the aircraft we could exceed that 20 deg up to point which was controlled by a red line painted on the Fwd main gear doors....during these operations the outrigger gear torque links had to be disconnected otherwise damage would occur.

I don't have a copy of that movie....watch again and observe if the torque links are disconnected aircraft may have been under tow for the filming...

[Flite-Metal]

In the pilot/copilot manual there are images illustrating a virtual 45 degree steering capability with the illustration showin the B-47
turning in its own length...

Today at our monthly meeting Horrace sat beside me. Horrace was a B-47 pilot and we discussed this at length. He did not recall
any mechanical relief for free castering during taxi, but that doesn't take into consideration an automatic unlock below an X ground
speed.

I will find the images I referenced earlier today. I do not recall if the scissor bolt is or is not present. Yes, I have seen the scissors
with the bolt removed. Note these two images are from an early B-47...and the strut is 180 degrees out in the two photos.

[Hircflyer]

yup! that's what looked like when disconnected...

Please notice that two pictures show the dropped link in two positions, left picture the link is on the aft portion of the tire the right picture shows the link on fwd portion of tire ....the landing light on the Dog House faces forward (yes that's what it was called)....this shows with the torque link diconnected the wheel was in a free caster (able to rotate 360 deg.)

The only way the lower strut of the outrigger could free caster is with the torque links disconnected and that was a strictly ground mechical operation.

When the bushings in the links wore the outrigger tire would do the super- market grocery cart wheel rata -tat -tat got your attention in the cockpit.

Wan't a bolt it was spring loaded pin which when pulled and turned 90 degs allowed the lower link to drop away.

[Flite-Metal]

Per the flight training manual T. O. No. 1B-47(D)(Y)E-1 for the B-47. Its proven to have been an excellent investment. I acquired it
from an Italian documentation source of all places. Its been a fabulous resource with respect to detailed cockpit and instrumentation
photos in addition to system definitions and use.

Unlike the 1:1 we will not use castering outrigger struts/wheels on our 10.2%.

[Flite-Metal]

I am not using this general layout however I am using it to audit the BAC drawing I was provided.