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RC Models => Gas/Glow/Nitro Planes => Topic started by: flatspin_king on May 24, 2012, 08:33:32 PM



Title: Top Flite giant scale corsair build
Post by: flatspin_king on May 24, 2012, 08:33:32 PM
hi guys,
  I haven't posted here in a while so thought I would share my latest project. I finally had some time on my hands this summer and decided to build the top flite 50cc corsair. Something about the sight of those bent wings in a turn...
The kit is not completely scale, so I am going to try and modify it in some respects to make it as close to scale as possible. This is going to be a long build! So far I have the Upper half of the fuse framed up - ready for sheeting.

If anyone has built the corsair please share your thoughts, suggestions and of -course pics/video. Thanks!


Title: Re: Top Flite giant scale corsair build
Post by: Pradeep on May 24, 2012, 08:52:23 PM
good going mate...!!! {:)} {:)} {:)}


Title: Re: Top Flite giant scale corsair build
Post by: satz flying on May 24, 2012, 08:53:33 PM
waiting (:|~ (:|~ (:|~ (:|~


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on May 24, 2012, 08:55:55 PM
The modifications I plan to make are
1. wing and tail incidence - the kit has the wing and stabilizer incidence set at 0 deg. The full scale corsair had a wing incidence of +2 deg and a stabilizer incidence of + 1.25 deg. This in my opinion is essential to the slight nose down attitude of the corsair in level flight.
2. wing tips - the kit has the angle at which the lower wing surface meets the upper one wrong - easy fix
3. vertical fin shape is wrong - again easy fix
4. going to make a scale retractable tail wheel
5. folding wings! (have to try this)
 


Title: Re: Top Flite giant scale corsair build
Post by: VC on May 24, 2012, 10:25:51 PM
All the best for this beautiful bird! She is one of my top favourites of all time classic warbirds.  :thumbsup:

The Japanese gave her the name of "Whistling Death" due to the high pitched whine that could be heard as she approached. This was caused by the airflow into the oil coolers situated at the roots of the wings. The Yanks labelled her "Hose Nose" due to her extremely long nose. (One of the reasons why I love her so - we both have similar features.) :giggle:

She was designed with Gull Wings to increase clearance for her massive prop and also to reduce undercarriage length.


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on May 24, 2012, 11:18:34 PM
thanks guys! VC yes, this is one of my favorites too - along with the spitfire of course. Will post pics as I go along. In the meantime here is nice up close and personal video of the real thing
 http://www.youtube.com/watch?v=nubn_QpkHnI


Title: Re: Top Flite giant scale corsair build
Post by: roopeshkrishna on May 25, 2012, 02:58:55 AM
great machine.. always.. (:|~ :thumbsup:


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 02, 2012, 07:08:47 PM
A little more progress... the top half of the fuse is skinned and rough sanded. Started work on the tail feathers. Although the stabilizer and fin-rudder are built up they are rather flat - I am modifying it to an airfoil shape, based on scale 3 view drawings. (although it will not be exact scale).


Title: Re: Top Flite giant scale corsair build
Post by: sushil_anand on June 02, 2012, 09:55:38 PM
Dear flatspin.....

Great to see your build log. Am looking forward to its first flights. I have always lusted for this plane but  everyone I know who has owned and/or seen one fly, say its a horrible flyer.

Hopefully this will turn out "right". My sincere good wishes for this project.


Title: Re: Top Flite giant scale corsair build
Post by: VC on June 02, 2012, 10:10:41 PM
Sushil Sir, one query - 'horrible flyer' for this particular model or any Corsair model? The reason why I am asking is that I've heard similar adverse reports about the Art Tech Corsair and its HK clones.


Title: Re: Top Flite giant scale corsair build
Post by: rcpilotacro on June 03, 2012, 05:30:24 AM
Corsair

by design is a compromise,  this anhedral dihedral was to accomodate a large prop (Because of engine limitation) and short undercarriage to keep weight down and height low, because corsair wast to fit into the lower deck of the carrier, undercarriage an inch more and the fin wouldn't fit

now this anhedral diheral is the bane on three counts

(a) at the point where the change takes place there is a huge vortex wake that gets generated and this vortex tosses about while flying interfering with wings producing asymmetric lift and unwanted yaw when this wake interacts with the fin

(b) this change point also produces a lot of interference drag

(c) aerodynamic performance of the aeroplane reduced considerably

produced by the sheer number it is well know but nowhere in the other warbirds league, and a PIA to fly, both RC and real


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 03, 2012, 07:57:23 AM
Actually I would have to disagree - It is a great flyer -both rc -specifically the top flite model, and the real one. The real corsair was the first to go over 400mph. rcpilotacro, I dont know what your source of info is but look at any corsair documentary on youtube - the anhederal wing actually increased performance. The anhedral was indeed introduced to accommodate a larger prop - a hamilton 13 ft prop - but it was not due to "engine limitation" -but because that was the largest piston engine in production at the time and could swing a 13ft prop - by comparison the ME 109 had just under a 10ft prop. The corsair was a great flying rugged design with a kill ratio of 11 -1! It was not by accident that the Japanese called it "whistling death".         


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 03, 2012, 08:25:42 AM
Dear Sushil, thanks for the encouragement! To answer you question - the TF corsair is a great flyer - even at 30lbs with all the scale accessories. (the normal wight range is around 24 -26 lbs. Like all warbirds it needs nose wight, which is why I have lightened up the tail as much as possible. Take a look at this huge build thread on RCU  http://www.rcuniverse.com/forum/m_3109744/tm.htm
Also check out the youtube videos of the model - I am posting just one for your reference http://www.youtube.com/watch?v=04GyhoJr4HI&feature=results_video&playnext=1&list=PL3BB3092A94554727


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 03, 2012, 08:31:14 AM
rcpilotacro, perhaps this video on the history of the corsair might put things in perspective?

http://www.youtube.com/watch?v=pHiM-i0slRA


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 03, 2012, 07:45:02 PM
 I took out some wood from the tail to minimize the final nose weight needed to balance.


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 03, 2012, 07:46:29 PM
push rod guides in place.


Title: Re: Top Flite giant scale corsair build
Post by: rcpilotacro on June 04, 2012, 05:56:50 AM
rcpilotacro, I dont know what your source of info          

real Corsair pilot ! on a professional interaction. having said that i take these propaganda videos with a bag full of salt. by no means i am saying it isn't a good aeroplane to fly. it requires skill to fly it. Induced Drag is high so slightly over powered engine is required.

PS
all aeroplanes are angels and would love to fly all of'em, RC or real


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 04, 2012, 06:42:32 AM
to each his own! I have talked to a few vets (at an airshow) who loved the plane. And actually its not a "propaganda video" as you call it - if you see parts 2, 3 etc.  they discuss the tip stalling tendencies of the early versions of the corsair -especially on the very slow approaches needed for carrier landings. But that was solved by adding a "stall strip" to the right wing leading edge so that both sides stalled at the same time. And also the plane was built around the engine - not the other way around. Admittedly it needed more skill to fly because of poor visibility for the pilot, especially in the context of carrier landings. This was also rectified in the later versions by adding a plexiglass panel to the cockpit floor. But it was a very rugged plane, that could take a lot of damage and still bring the pilot home. It was clearly superior to the Zero - its main adversary, as the 11 -1 kill ratio demonstrates.         


Title: Re: Top Flite giant scale corsair build
Post by: rcpilotacro on June 09, 2012, 07:03:44 AM
Sir

like i tell my pupils who get into discussion as to Mirage 2000 is better or MiG 29 is better? neither were made by us and i for one love to fly all these babies, more difficult it is to fly, more challenging it is, having said that, here are few issue that plagued F4U, kill ratio in the last stages of war was due to better designed F4U and flown by good pilots vs poor zero with no armour flown by rookies with death wish, here are some excerpts

Engine restrictions

The F4U incorporated the largest engine available at the time: the 2,000 hp low RPM P&W Engine. To extract as much power as possible from this low RPM Engine (if i draw an analogy, it is Like a low Low KV high wattage motor), a relatively large Hamilton Standard Hydromatic three-blade propeller of 13 feet 4 inches (4.06 m) was used. To accommodate a folding wing, the designers considered retracting the main landing gear rearward, but for the chord of wing that was chosen, it was difficult to make the landing gear struts long enough to provide sufficient clearance for the large propeller. Their solution was an inverted gull wing, which considerably shortened the required length of the main gear legs. The anhedral of the wing's center-section also permitted the wing and fuselage to meet at the optimum angle for minimizing drag as much as possible, without using wing root fairings. Offsetting these benefits, the bent wing was heavier and more difficult to construct.

F4U-1s had difficulty recovering from developed spins, since the inverted gull wing's shape interfered with elevator authority. It was also found that the Corsair's starboard wing could stall and drop rapidly and without warning . In addition, if the throttle were suddenly advanced to WOT the port wing could stall and drop so quickly that the fighter could flip over with the rapid increase in power. These potentially lethal characteristics were later solved through the addition of a small, 6 in long stall strip to the leading edge of the outer starboard wing like you covered. This allowed the starboard wing to stall at the same time as the port. (What a solution) :banghead:

The Corsair was not considered fit for carrier use until the wing stall problems could be solved. In the event, because the more docile, and simpler to build F6F Hellcat had begun entering service, Corsair deployment aboard U.S. carriers was to be delayed until late 1944 (by now young jap rookies began flying as cannon fodders to F4U)


Title: Re: Top Flite giant scale corsair build
Post by: VC on June 09, 2012, 11:50:11 AM
The Corsair is one of my all time favourites, that being said, the kill ratio of 11:1 does not justify the villified reputation of the Zero.

The Zero did not have adequate armour protection or self sealing fuel tanks. One tracer bullet into the tank and it was doomed. Coupled with the fact (as already pointed out by rcpilotacro) that Japan was throwing everything at the Corsair from Rookies to Teenagers with no flying experience - that kill ratio was comparatively easier to achieve.

Had the Corsair been around the European theatre earlier, say 1942, I wonder how it would have done against the FW 190 or the Me 109. 11:1? Unlikely...............

On a similar note, Erich Bubi Hartmann, claimed 352 kills in WW2. About 200 of these kills were against the slower Sturmoviks, Peytlakovs, Lavochkins and Yaks. Does that confirm him as a better pilot than Moelders or Galland?


Title: Re: Top Flite giant scale corsair build
Post by: rcpilotacro on June 09, 2012, 01:18:45 PM
precisely ! put !

Which is the reason Oswald Boelcke, Albert Ball, Billy Bishop, Billy Barker, Adolf Galland, Mick Mannock, Rene Fonck and Red Baron remained my all time favorites


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 10, 2012, 01:46:27 AM
ok guys, we can argue about this until the cows come home. Each plane has its pluses and minuses and goes through many design modifications/improvements. Heck the engines themselves went through many refinements with turbochargers etc to extract every last bit of power. (this includes the famous RR merlin engines common to the spitfire and some other RAF aircraft) Incidentally, the P&W R 2800 was also common to the Hellcat and P47 thunderbolt. (again the debates about low vs high rpm, torque vs top end speed are endless) The lack of self sealing tanks and heavy armour plating was a minus for the zero -correspondingly its greater maneuverability was a plus. Interestingly the wikipedia article that rcpilotacro is quoting from also has this quote from the first corsair ace, Kenneth A Walsh.

 I learned quickly that altitude was paramount. Whoever had altitude dictated the terms of the battle, and there was nothing a Zero pilot could do to change that we had him. The F4U could outperform a Zero in every aspect except slow speed manoeuvrability and slow speed rate of climb. Therefore you avoided getting slow when combating a Zero. It took time but eventually we developed tactics and deployed them very effectively... There were times, however, that I tangled with a Zero at slow speed, one on one. In these instances I considered myself fortunate to survive a battle. Of my 21 victories, 17 were against Zeros, and I lost five aircraft in combat. I was shot down three times and I crashed one that ploughed into the line back at base and wiped out another F4U.
 
     Also two historical facts - the corsair saw a lot of success against the zeros when it was flown by the marines in guadal canal in 1943, before the Japanese became desperate -sending up rookies on kamakazi missions. Secondly it was the British who successfully operated the corsair from carriers ( with many design refinements such as improved landing gear with a bleed valve to take away the 'bounce' of the early model corsairs.) The success of the british helped in changing the minds of the Americans with respect to carrier operations, and they were fully inducted into the navy in 1944.
However, since none of us has actually flown a corsair and are unlikely to do so anytime soon I guess we would never know! However from all accounts the TF rc version flies very well - and thats my main concern right now!! :) So ... to get back to the RC version ... I have been working away - this thing is built like tank - (or should I say a log cabin) pics to follow this post...             
 


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 10, 2012, 02:23:20 AM
This is the change I made to the wing saddle for +2 deg wing incidence - for a more scale look.   


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 10, 2012, 02:25:37 AM
clamped with 30 min epoxy (sorry pics have to be posted individually as they are rather large -even after being cropped)


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 10, 2012, 02:28:18 AM
fuse bottom - ready for sheeting


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 10, 2012, 02:31:21 AM
turtle deck shaped - might need to refine the shape a little bit more.


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 10, 2012, 02:42:07 AM
managed to impart an airfoil shape to the rudder - needs more work. The kit comes with provisions for a flat rudder - so lots of sanding to get to this point.     


Title: Re: Top Flite giant scale corsair build
Post by: rcpilotacro on June 10, 2012, 05:22:20 AM
However, since none of us has actually flown a corsair and are unlikely to do ..

Disagree !!
lucky you, you are going to fly one, and i am following this post with interest as soon i am embarking on Meister Scale ME 109, 100" Platinum Kit or Meister FW 190D9 (Insha Allah), so, this thread and you pics will be the start point, great going sir :thumbsup:


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 11, 2012, 11:07:21 AM
thanks rcpilotacro. But Its my turn to be envious - the Meister kits are awesome and much more accurate in scale than TF. I have always wanted one. It would be great if you could do a build thread here. At 100" what is the weight range you are looking at and what engine are you going to use?     

ps, not much work on the corsair today as I was out flying - had a blast with my 50cc extra - my dle 55 is running like a swiss watch, first flick starts every time after initial choking for the first flight of the day.   So much so that I am seriously considering another one for my corsair, although I might need a heavier engine like the Zenoah G62   


Title: Re: Top Flite giant scale corsair build
Post by: rcpilotacro on June 11, 2012, 01:05:19 PM
Contemplating 3W 80Xi, going to cost me a bomb, since i dont have any other vice, wifey has been kind enough to allow me this indulgence

PS
i might have a Zenoah G62 runin lying around somehwere,


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 23, 2012, 09:06:27 PM
ok guys -another update. Progress has slowed as I am trying to finish my 33% yak and get it in the air. But I did manage to glue in and reinforce the firewall - added another 1/4 inch birch ply sheet to the supplied firewall and also put in basswood tringle stock reinforcement (instead of balsa as per the kit). Also finished sheeting the bottom of the fuse. Next on the agenda - the inverted gull wing center section (that should be fun!)
The third pic is of the yak - I need a bigger apt.!


Title: Re: Top Flite giant scale corsair build
Post by: sushil_anand on June 23, 2012, 09:15:52 PM
A smaller plane would, effectively, have the same end result! ;D


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 29, 2012, 08:34:03 PM
A smaller plane would, effectively, have the same end result! ;D

You are absolutely right! This addiction has no limits ;D

Ok, another update - made some good progress over the last week on the wing. First pic is the wing center section under construction - for obvious reasons it cannot be built over the plan. I was a bit apprehensive but it went together quite well.

   


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 29, 2012, 08:37:35 PM
first pic - completed center section. Second pic - left panel (this was quick and easy)


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on June 29, 2012, 08:54:48 PM
 first pic -  center section and left panel - thinking about how to make the wings foldable. second pic is of the right panel under construction - who says books don't have any practical use  ;)


Title: Re: Top Flite giant scale corsair build
Post by: ujjwaana on June 30, 2012, 12:26:24 AM
Wow!!! Bookmarking this thread!!!


Title: Re: Top Flite giant scale corsair build
Post by: VC on June 30, 2012, 01:44:36 AM
Pity that I have NOTHING to post to add value to this thread. All that I can say is that I am overwhelmed by this build. All the best King, hope you never ever have a flat spin with this baby.  :bow:

As far as a 'Bigger apartment' is concerned, we are on the same boat. I've rented a separate premises (750 sq. ft.) to house my Aero / RC endeavours. At the moment it is out of bounds for me because a Mummy Cat is bringing up her litter of four and training them to climb up and down over my Styro and Depron piles (Honest!!!) I don't want to disturb them or scare them away.

My only responsibility is to aid my Daughter who ferries across their regular supplies of shredded Tuna and Taaza Milk. Healthy diet, eh? I am a vegetarian................ :headscratch: ???

C'est la vie!


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on July 25, 2012, 10:38:44 PM
thanks guys! I have been away on vacation so not much progress on the build. In the meantime I also bought another 50cc and was working overtime to get it ready for the weekend - (put it together in a week - I wish I could do the same with the corsair!) did get some 'goodies' for the corsair though.

VC your rc work premises (once the mummy cat lets you back on premises  :)) are the size of my entire apt! And I have 4 giant scale planes and a fifth (the corsair) being built. Needless to say my significant other is not very happy! But I promised to sell atleast one plane. Some pics of my designated "hobby area"


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on July 25, 2012, 10:42:31 PM
some more - the plane in the closet is awaiting repairs.


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on January 22, 2013, 09:57:41 AM
hey folks! So a university degree and several ARFs later I am back to building the corsair. Made some progress this weekend - the conversion from the stock flat stab  :banghead: to the air-foiled one is almost done - need to sheet the top half and sand.  Started work on the fin.   


Title: Re: Top Flite giant scale corsair build
Post by: sanjayrai55 on January 22, 2013, 10:48:55 AM
Great build going on flatspin. I'm really enjoying watching it. All the best!


Title: Re: Top Flite giant scale corsair build
Post by: flatspin_king on January 23, 2013, 09:39:45 AM
thanks Sanjay. Glad someone is still watching this build! lol - I'll try and work steadily and update regularly. That way I won't burn out with the whole building process. 


Title: Re: Top Flite giant scale corsair build
Post by: sanjayrai55 on January 23, 2013, 09:47:41 AM
There is a certain purity about a conventional Balsa build, and yours is going along superbly :)