voyager_663rd

I came across this interesting site in my travels. I know there are many but what was interesting was the fact they mentioned the right wing spoiler (and it's use) as well as some of the construction detail.

One characteristic they do mention is that fin was offset to compensate for the torque. I DON"T think I want to try to add that mod to this discussion but those who are more ambitious may consider it.

http://www.vectorsite.net/avf4u.html#m2

The F4U-1 was of basically conventional monocoque construction, made mostly of metal. The ailerons had wood frames and plywood skinning, while the rudder, elevators, and outer wings had metal frames and fabric skinning. The flaps were all metal. The tailfin was slightly offset from the centerline to help compensate for engine torque. There were trim tabs on the ailerons and the rudder.

and an almost unnoticeable 15 centimeter (6 inch) fixed "stall strip" that was fitted to the leading edge of the right wing outboard of the guns to ensure that both wings stalled at the same time on landing approach


Love this bird.

voyager_663rd

Having the bomb/rocket racks loaded will cause substantial drag. Won't having this tank on (although it would look sooooo cool), make it that much more "inefficient"? Got the horses for it?

F4U Killer

I had been wondering for a long time what the spoiler looked like that tamed the Corsairs Tip Stall.
I found a Book with a lot of Graphics in it this past Christmas and it had the Spoiler in it.
From a side view the spoiler looks something like this Key stroke }
I had never imagined something so minuscule would have such an effect.

The Book that I purchased

Corsair 30 years of Filibustering 1940-1970

CorsairJock

My Feedback: (90)

voyager_663rd, yes the yellow area is where the additional wood (balsa) needs to be.
I am aware of the fin offset AND the 'spoiler' The spoiler was on F4U-1D and later models, it is indeed 6" long, and is just outboard of the right wing machine guns. The idea was to get the right wing to stall just a little quicker (than a right wing without the spoiler), thereby making it stall almost a quick as the left wing.

I have assembled the drop tanks, and installed the Vortac release parts onto them: the pair weighs about 134 gr at this point, a little over 4 oz without paint. The servo and remaining parts will no doubt add a few more oz. My 8 lb, 10 Corsair may become an over 9 lb Corsair when all is said and done. I don't think the drag will be too much of a factor, as the tanks are pretty streamlined. But the added weight will be pushing the Saito .72 to it's limits. Maybe I will only carry 'external stores' when the temps are mild, say in the 70s. Time will tell, and I'll keep all infromed.

About those drop tanks: I originally listed them as part #109, that was an error on my part, they are #AC901 (but #901 is all that is on the label). Sorry for the mix up.

voyager_663rd

PHEW. This post deals with the importance of doing all your research BEFORE actually cutting/gluing any parts.

As you may know, I am patterning my bird after Lt Hammy Gray, VC DSC RCNVR. He was based with the FAA operating in the South Pacific. Because of the unique "flight" characteristics of the Corsair, a new landing pattern had to be flown in order to land on carriers. Basically, it was a "circular" pattern until literally just before landing on the deck, the pilot leveled out. Something to do with the long nose.

Anyways, British carriers will somewhat smaller than U.S. ones and it was determined that if the wings on the Corsair were "clipped" by 8", it drastically improved its low speed (stall) handling characteristics. That wasn't the intention (it was so the bird could fit in storage) but was a welcome side-effect.

So, although Corsairjock's mods include a re-designed wingtip, mine will ALSO include a re-designed BUT DIFFERENT wingtip--8" shorter and blunt. With the 1/8 scale, that brings it to a 1/2" squared-off stub at each tip.

Maybe not as esthetically pleasing to the eye, but it will most assuredly be distinctive.

I'd like to thank Jim for his dedication to bringing the "correctness" back to this particular plane. There are others (Dion comes to mind) as well who have contributed much to this discussion and you know who they are. Without his input, I would have not researched this topic to the extent that I have.

Thank you Jim for a job well done.

Len

CorsairJock

My Feedback: (90)

Yes, the U.S. Navy intitially did not consider the Corsair suitable for carrier based operations, and thus regulated the unwanted aircraft to the the U.S, Marines for land based operations. The British on the other hand, recogonized what a great aircraft the Corsair was, and with their 'we must sink the Bismark' determination decided to 'make it work' (from carriers). One of the problems was the long straight nose, which severely limited forward visibility during those difficult carrier landings. The British came up with a few ideas which resulted in changes to production Corsairs, AND developed the sweeping arc landing pattern which allowed the pilots to maintain sight of the carrier until the last few moments, by which time all they had to do was cut the power and drop to the deck. Thanks to the British, the changes in design and procedures prompted the U.S. Navy to take another look at the Corsair. When they finally did accept it as carrier suitable, they did so with great earnest. By 1945, some Essex class carriers had more Corsairs stationed on them than all other aircraft combined, because the Corsair could not only out-duel most Japanese fighters in combat, but it could also carry a heavy payload of bombs and rockets for attack strikes, some against Japanese homeland manufacturing sites. The U.S.S. Bunker Hill had over 70 Corsairs stationed on her in 1945, other carriers had simular numbers.
The Hellcat was a great plane also, because it was much more pilot friendly to all those newly trained pilots. The Corsair was a hot rod in comparison, having superior performance but not for beginners.
BTW, the reason for 'clipping the wings (on British versions) had to due with the heigth of the British carrier hangers: the ceiling was lower than U.S. carrier so a rounded tipped Corsair did not have suffient clearance. It was determined that clipping the wings also had a desirable effect on landings as mentioned, by requiring a slighly higher landing speed but with reduced stall tendancies.

voyager_663rd

While the glue dries, more research into techniques. I had a feeling that any decals I MIGHT find would be difficult to apply/colours may not be correct etc etc.

Came across this site for painting your own decals, insignia on plastic models. The practises here will be applied to mine. Hope you find it usefull. Now to find the correct colours to use.

http://www.ipmsstockholm.org/magazin...intdecals1.htm

F4U Killer

In 86 I had just moved to Reno, Nev and I was doing some work out at Stead where the Reno Air Races are held.

The Races start on Thurs, but the days preceeding the Races you can get in for free and watch the planes make runs and practice on the course.

The only up close Corsair I have ever seen was a Clipped Wing Corsair.
It had US marking's on it and faded paint.

I was in Love with the Corsair every since The Black Sheep came out and as I was standing there watching this plane run up. I was thinking what a shame it was for this guy to ruin this plane by chopping the ends of the wings off.
I was also thinking these guys will do anything to gain a little extra speed at the exspense of the Plane.

At the time I did not know the British ever saw a Corsair.

I now wish I could turn the clock back and be able to talk to the pilot to find out the history of the Bird

voyager_663rd

Thanks for the story F4U Killer. It's nice to add personal touches to this topic. I don't feel so wrong now about adding a little bit more "history" to it. With Jim having said he's basically finished with mods for this one, here's a bit more "story".

In my research, I came across why there were so few corsairs left in British possession after the war. The corsairs that Britain obtained were through the U.S. Lend Lease program. They were provided free to their British allies as the U.S. contribution to their war effort.

That was one of the reasons the U.S. govt offered its citizens for their "largess". "Hey folks, it's only a loan. We're going to get them back when the Limey's are through with them".

Well, the end of the war came and so came the end of Lend Lease. The U.S. didn't want the birds back. The Brit's couldn't afford to pay for them. With the blessings of both the British and U.S. government, the VAST majority were outright destroyed--literally, sailors pushed them off the carrier decks into the Pacific to sink to the bottom of the ocean. Those that were still on land were sent to wrecking yards where they were crushed flat as pancakes. None were to survive save those that were either shot down/abandoned elsewhere or "spirited away" by private individuals.

Kinda reminds me of the story of our own Avro Arrow. Different circumstances but still, destruction at the hands of the governments of the day. Anyways, here is one of the stories, as I found it as written by K S Nair:


Japan, 1946

Imagine a coalition air force consisting of American, Australian, British and Indian fighter squadrons, operating from airbases close to a city devastated by nuclear strike, patrolling the seas around the Korean peninsula. This is not a fictional scenario from the latest Humphrey Hawksley or Tom Clancy techno-thriller - it was actually happening, 57 years ago.

In early 1946 No 4 Squadron, Royal Indian Air Force, was selected to go to Japan as part of the British Commonwealth Occupation Forces. The selected contingent numbered 40 officers, of whom 25 were pilots. Seven of those 25 were the new Pilot Officers.

It was decided that the squadron would ferry its aircraft from Bangalore to Cochin (now Kochi), where they would embark for the voyage on a Royal Navy aircraft-carrier. The squadron was told that they would not have to land on the carrier - their aircraft would be loaded on - but they might have to take off from the carrier when they reached Japan. They therefore fitted wingtip extensions onto their aircraft (which were otherwise clipped-wing variants), and developed wooden pegs to hold the flaps in a suitable position for short take-offs. They practised short take-offs, until they could all take off within 200 yards.

BN Surendra, one of the Indian DFC awardees, brought a case of Scotch to the squadron the night before they were due to ferry their aircraft to Cochin. It was 1st April, Air Force Day, and an occasion for celebration; and the pilots may have, ill-advisedly, sat up and finished Surendra's gift.

Pilots and aircraft set out for Cochin the next day, 2nd April. The first section of four aircraft was led by Flying Officer WR Dani flying NH795. On approaching to land at Cochin, which had a short runway with grass on the approach, he hit telegraph wires and overturned. He survived the crash, but suffered glycol burns and could not travel with the rest of the squadron to Japan. (WR Dani was later to command No 5 Squadron when they converted to Canberras, and to retire after a distinguished career as an Air Commodore.)

At Cochin, there was a batch of brand-new Vought Corsairs, American-built carrier-borne fighters that had been provided to the Royal Navy Fleet Air Arm under Lend-Lease. They were so new that they still had brown-paper coverings on their instruments; but as they were Lend-Lease aircraft, they were required to be scrapped, now that the war was over. Again, RAF and FAA personnel were surreptitiously and systematically stripping them of their radios. The RAF Station Commander caught on, and announced a general amnesty if all the stolen radios were returned and placed "outside my office by tomorrow morning." Whatever the alternative it can't have been pleasant; Digby recalls that most of the radios were in fact returned by the deadline.

Ironically, the Corsairs were disposed of, in keeping with the requirements of Lend-Lease, not long afterwards. 30 of them, together with FAA Types as Corsairs and Helldats, were actually loaded onto the same aircraft carrier as No 4 Squadron, and were simply pushed overboard once the ship had reached deep water.

http://www.bharat-rakshak.com/IAF/Hi...s/Digby02.html

More stories to be told. . . . .

hatnikman3

Fantastic thread guys, I wish I had something to contribute. I am new to this "scale stuff" and have been sucked into this thread in particular while building the TF Corsair.
Amazing the knowledge some of you folks have (I'm envious). I am building the "full blown" version (as if there was any other way) & would love to know where you folks get the decals that go w/the 1D, tri colored version. I have searched many places & have not received clear answers or they cost was more than the plane kit! I've seen the some beautiful marine dreams out there.
I had to grab a Kleenex after hearing they shoved those planes off the carrier decks!! Long live the Corsair!
Thanks in advance for any help. Nick

voyager_663rd

I'm nowhere near that stage but having spare time while the glue dries, I've found that concerning my bird, it may be that painting the rondelles, etc on may be the best way to go. Trouble with that method is making sure they are perfect as far as symmetry (sp) goes--round not oval/wobbly/etc comes to mind.

Colour match-ups is another consideration. Mine will have FAA colours which was different in the South Pacific for corsairs as opposed to the ones based in Europe. They needed to ensure that the rondelle was not mistaken for the rising sun at distance so both colour scheme and design were altered. Research, research.

I'm starting to find that I enjoy the research as much as the building.

nkypockets, ss your bird patterned after ONE particular plane or just the variant/location in general? That may/probably will influence just how you proceed.

Rocketman612

My Feedback: (85)

Nick,


I placed my order with Denny ay Model Graphics here is the link: http://www.cajunrc.com/Model_Graphic...ary_choose.htm
Decal set consists of:
4 National Insignias
2 Lg #3 for Fuse
2 Sm#3 for Air Break
2 Jolly Roger flags
5 Kill markings
1 set of "nomenclature" ie "no step", Hamilton prop decals,etc

He was able to size down the decals for the Ziroli but is not sure how readable they may be. Cost is $75 plus $6 for USPS priority delivery. Not bad and MUCH easier than me trying to paint them.

Pete

hoonnz

CorsairJock

In post 132 you showed how you put in a scale web between the inner and centre flap - how has this worked out? Can you give more details, maybe a sketch please as I wanted to do this but was concerned at how the angles change as the flaps go down. I'm building the centre section of my wing so this is the time to plan these things.
One point that hasn't been discussed is that the flaps are not very scale in size. the middle flap is far too big and should be straight, the inner flap should be longer with a slight curve on the end, and the outer flap should be a little longer. The photo below shows this perfectly.

In my kit the two sticks of balsa for the flaps and ailerons were a terrible mismatch. One weighed just over 40 grams, the other about 130!

Brian

CorsairJock

My Feedback: (90)

hoonnz, EXCELLENT photo of flaps, really showing what they SHOULD look like. Also showing the step which was discussed earlier. And good point: the flaps are another area where scale inaccuracies abound. ALL the flaps should be wider (front to rear, NOT thickness). The outermost ones, as well as the ailerons, should have a slight taper in width, getting wider as they are closer to the root. The center ones (on each wing, NOT the ones centermost to the aircraft) should be nearly mating with the outer ones, and the only place there should be a significant gap is between the innermost ones and the center one, which is where the web comes into play.

The pictures that I supplied of the webbed flaps are of my still uncompleted 'red box' Corsair, and nothing further has been accomplished since I too those pics. But I will take some time a little later to explain and take more pics. My inner and outer flaps are basically scratch built, only the center ones more or less follow plans.

A lot of times, I do not notice the scale inaccuracies until AFTER I have built the inaccurate part. I look at it and say to myself "Self, that don't look right", then compare to scale drawings and sure enough, I'll need to make adjustments NEXT time. The more we expose here, the more many of you will not have to wait untill next time. And again hoonnz, you are correct: there are a lot of inaccuracies in the flaps. But Ill have to get back to this subject later, running out of time right now. I will add that my webs are made from 1/16" hard ply. I plan to paint and put something like an expoxy coat over them, so they will have a smooth hard surface.

rlawrie

hoonnz
Great picture! The detail is amazing.
This is really in response to your message in Post 221 concerning cowl mounting and operating cowl flaps. I would expect there would be as much air (cooling) trying flow under the cowl flaps as over them when the engine is running full bore during a straffing run, so the required spring compression would be very sensitive. I'm thinking about using small electromagnetcs (homemade with pieces of iron nails and some magnet wire) and pieces of refrigerator stickup material. This would still require springs. I'm going to try to build a few samples and see how much current is required to make a useful magnet. Since I'm planning on replacing the kit's cowl and cowl ring, I'm looking at attachment access through the cowl flaps.

There is a picture of a beautifully done, highly detailed F4U-5N in the April issue of Model Aviation. Details include "functional cowl flaps controlled by the engine." The model was built by Earl Aune. I'm sure the model is much bigger than 1/8 scale but I'm going to try get in touch with Mr. Aune and ask how he did it. Assuming I can find Mr. Aune and that he is willing to share his knowledge, I will post anything I find.
Semper Fi,
Dick

WarpdSpazm

IS this the Black Corsair with orange lettering... If so it's been around for a while and is amazing... It has fully functional folding wings as well... and I do believe it was a small scale... Under 1/5 for sure... There's a webpage showing it... I'll find and post the link.

WarpdSpazm

http://www.strictlyscale.com/earlaune.htm

it's 76" which is roughly 1/7 scale.... ok ok 1/6.7 to be exact... but not too much bigger than our 65" birds though that little difference is enough to do what he did and fly... on a 1/8, i think it'd be too much.


also this might be a good reason it was in the magazine... it's up for prize in a raffle... think i might have to buy me some tickets
http://www.mikechilson.com/ussma_southeast/

voyager_663rd

Hehe. 1000 hrs over 7 yr.

But oh so nice.

rlawrie

Yep! That's the one. Thanks for the link.
I think I'll have to buy somw raffle tickets.
My search has ended as a company called Oregon Scale Aviation has acquired the design.
I'd like to come up with something so that the pilot controls the postion (open or closed) of the cowl flaps. Wouldn't we all.
Semper Fi,
Dick

hoonnz

Dick, I think you're probably right about the air flow not working right to open or close the cooling gills. I've got another idea.
I'm going to try a mockup using a ring of curtain wire - you know , the stuff like a long tight coil spring about 3/16" diameter. If you twist one end the whole length twists even though it is bent in circle. If that doesn't work I'll try steel cable, like they use on bicycle brakes. Actually thinking about it I like the second option best. Support it inside the cowl with a support between each cowl flap. The flaps will be fixed to the cable and will open as it twists - hopefully.

Brian

WarpdSpazm

The bike cable will work, but not as you're thinking. the flap nearest the control point will open and close properly. BUT as you go around the wire each consecutive flap will move less and less as torsional flex (i think that's the right term) in the cable increases; so you won't have equal travel on the flaps...

There are a few methods floating around here on RCU that guys have used to success. Will they apdapt to a 1/8 model? I'm not sure.. I'll post links as I find them again.

kram51

My Feedback: (3)

I had read somewhere about a guy using Nyrod to actuate his cowl flaps. As best as I can remember he made a loop of inner Nyrod and joined the ends with a short piece of threaded rod. The Nyrod was adjusted to hold the flaps closed when cold. The idea being that as the Nyrod heated up, from the sun and motor generated heat, it would expand and open the flaps automatically. The inner rod was connected to the flaps with short sections of the outer sleeve. I would love to know if this actually works. I can't remember where I saw this though . . . .

Mark

hoonnz

Ray,
I know what your saying, but I think it is worth pursuing - the cable forms a big circle so both ends meet and are driven. Also the cable can/will be stiffened where it has each flap glued or whatever to it, and the flaps are shaped so that they overlap at the back, so they can help to push out their neighbour.
Finally, this method would be quite simple with just one control link driving all the flaps. That alone makes it worth some effort. When I get a chance (busy busy workwise currently) I'll do some testing.

Happy landings
Brian

hattend

My Feedback: (20)

Okay, since I don't have a program to draw this, I hope I can describe it well enough so you will see it in your mind's eye.

Instead of using a cable and wrapping it around in a circle and then twisting it, why not get some music wire and shape it in a circle that fits into the cowl. Then mount two servos 180 degrees out from each other inside the cowl. solder some tabs to the wire circle so you can connect the servos to the wire loop.

Then solder tabs around the wire loop at each cowl flap location. Each cowl flap will have a connection wire from a point on the flap to the wire (they all should be in the same place so you get equal movement).

Hook the servos up to a Y-connector so you get the same movement when you activate the transmitter control (switch, slider, button). the servo moves the wire ring fore and aft about 3/4" to 1". This fore/aft movement will cause each cowl flap to move up or down as the attachment point on the ring moves toward or away from the cowl flap. Each flap is hinged on the front so the only way they can move is up or down.

Now, mount this whole thing on the cowl so you don't have to unhook anything except the servo wire when you have to remove the cowl and it's essentially self contained. If you need more stiffness in the system you could make some ply tracks for the wire ring to ride in.

If this isn't clear, sorry...wish i could draw a picture. Maybe I'll do that tonight on paper and scan it and post later.

Don

hoonnz

Don
That method has some appeal, and if the twisting cable approach doesn't work I'll look at it.
The way you describe it, it needs the ring with attached tabs, links to each flap, hinges for each flap, and two servos. That's a lot of mechanics and maybe some metal to metal.
I hope the twisting cable can be driven by the last 1/4 of the throttle servo movement (idle end so the flaps open at low speed) and the flaps will be glued to the cable so there are no links or hinges. The simpler the better.
This should not degenerate into an argument, and that is not what I am trying to do - I love the flow of ideas and I hope you and others might make a mock-up of your schemes and prove them. I have a bit of time before I get to that stage of construction so the more ideas the better, and I'll borrow the best!.

Cheers
Brian