TF F4U Corsair - 2 Questions
 

Having read with interest the various threads on CORSAIRS I have decided [as an intermediate flyer who likes to keep progressing] to build theTopFlite 62 inch wingspan version as a first warbird.

1) Engine choice. At present I could use either an Irvine 72 two stroke or a Saito 100 four stroke. Would either be suitable - or is there a better choice?

2) The instructions in the downloadable manual seem to suggest that the wing is built on top of the workbench almost as a freestanding item - i.e. there doesn't appear to be any kind of extensive jigging to ensure absence of warps, etc. Is this OK in practice or is there a better way?

Any advice on the above, or anything else, will be much appreciated.

TF F4U Corsair - 2 Questions
 

Not to throw water on your fire, but I would suggest the TF P-47 first. If you've read the threads you should know about the problems with the retracts. Aside from the retracts, the TF corsair is a great plane. But the P-47 has a history of being more forgiving and the retracts are easier to deal with. Just my opinion.
Edwin

TF Corsair
 

Runway,
To answer #2. The wing tips are built on the table and are designed to build in the washout needed. Not a problem. The center section is also built over plans and if done per plans is also fine. Just go slow measure twice and cut once :)

Answer to #1 is open to debate. The Saito 72 would be fine. If you want a total in cowl engine consider the RCV 90. Go to Juice's site and see his installation http://members.rogers.com/jsrc/
More power? 3 blade prop? Gas? Consider the RCS 1.4 . Do some searches and decide. The good thing is that your final engine decision can wait. Choosing retracts won't. Pete

TF F4U Corsair - 2 Questions
 

Thank you to both Edwin and Pete - your advice much appreciated.
I'm now thinking of NOT fitting retracts as I fly from a grass strip and I've seen a number of retract flyers come to grief on this type of surface.

TF F4U Corsair - 2 Questions
 

I prefer to fly my retract (Robart) equipped Top Flight Corsair from grass runways. Only problem is when I taxi into one of them critter holes.

TF F4U Corsair - 2 Questions
 

I fly a fixed gear TF Corsair with a Saito 100. The valve covers are outside of the cowl a little bit. Just about a perfect combo in my opinion. I had to add about 2 ounces of weight on the firewall to make it balance a litttle nose down.
Fred

TF F4U Corsair - 2 Questions
 

Runway;
I've build a couple of these Top Flight Corsairs...and I have flown them sucessfully...but they have some flaws.
I had a superTigre 90 in both of mine...and that seemed to be plenty of power. Something equivalent would be fine, but this plane needs lots of power because it's heavy...and wing loading is heavy. Build it light where you can.

Here's a tip, which may help you TF builders...and it goes back to full scale aviation test piloting...

I had a problem with one of my corsairs...and I had bought this from a guy who had flown it, but hadn't mastered it. It was already built, and built well, I might add. One of the problems with the Top Flite is the incidences. They've changed the incidences of the wings and tailplanes...and the airplane doesn't even LOOK like it flys through the sky right....it sort of slumps in flight...tail low...notice that? Don't modify your kit, unless you know what to make the incidences, but let's say that they're not like they should be.

Also, my corsair would turn turtle in a loop. If it would spin, it would have a hard time coming out...balance was good, and there was no differential in the elevators...they were well connected, and well driven. I took the plane up, and learned to slow fly it...you should always do this...and STALL IT. STALL IT, because you NEED to know where it's going to stall...or at about what speed. Be conscious of your stick throws at the stall, and guage the speed.

This corsair in a stall dropped a left wing very abruptly...like the full scale corsair. The reason is propwash over the right wing root....which has lifting air, when the left wing root has sinking air from the prop...it's inherent in the design of the inverted gull wing, and the corkscrew effect from propwash. It's even more pronounced in the RC planes, because of the rpm of these little engines....and they put lots of propwash across the surfaces. I stalled this thing, and every time, VERY ABRUPT drop in left wing.

Then I landed it, and cut a 1/8th inch groove, an inch long, in the right wing leading edge just outboard of where the guns would be...and installed a stall strip. Just a little piece of lite ply...and it was a field repair. Took it up again and stalled it....Now it dropped the right wing gently...so I landed it, cut a quarter inch off the stall strip's length, and the airplane was a whole new bird. It would float so nicely. I could slow it down so slow in landing that you could touch the grass, hold it there with a blip of throttle, and just float. It's a docile plane, but it's somewhat flawed. Work out the flaws, and you'll love it. Remember USE RUDDER IN EVERY TURN> I even have trained myself to initiate turns with rudder..and invariably you're on opposite aileron through the whole turn, but they're so coordinated and the plane really flies nicely. Give it a try!

TF F4U Corsair - 2 Questions
 

Hey JimoCooper,

Glad someone else noticed how bad the TF Corsair looks! They do need to redesign this kit, really bad! The nose in front of the canopy is not the right shape either, fuselage is to round in front of canopy.

Compare these pictures, the first is a TF Corsair expertly built by Bob here on RCU, great job! I am just pointing out the design flaws however. Wing and tail incidence and top front of fuse:

TF F4U Corsair - 2 Questions
 

Now the full scale:

TF Corsair
 

Dion, Great analysis!.. One thing I noticed with the kit was that when landing, the plane never wanted to groove. It was always hunting during decent. By that I mean it was difficult (for me atleast) to find the sweetspot between rate of decent and air speed. I can see the Incidence difference between the kit and the full scale.. big difference!.. That would explain a lot of things.

I would DITTO the P-47 pic as a First Warbird... They have Great flying qualities... It seems as thought the Ziroli Corsair flies much better.. from what I have seen over the years. Regards BobH.

Wing and Stab incidence
 

Well this could be helpful as I'm within sight of mounting the wing ! TF calls for 0 incidence of both wing and horizontal stab. Luke did you use different? Any TF 60 Corsair builders out there use anything different and what were your flying results? Pete

TF F4U Corsair - 2 Questions
 

Hey Pete,

I don't think it would change a thing, except it will look better in the air and on the ground. The wing might fit better too, you will be able to put a better fitting belly pan on it. But it's a gamble like anything else you mess with! The Brian Taylor .60 plan calls for 2 degrees positive on the wing and 1 positive on the stab, you make the call! :p

Luke

For your kit bashing enjoyment I offer the following in assistance!

TF F4U Corsair - 2 Questions
 

And the stab incidence:

TF F4U Corsair - 2 Questions
 

This is all excellent advice, everyone - thank you. Exactly the kind of thing RCU is famous for.

JimoCooper - am intrigued by this idea of a 'stall strip'. Could you expand on this, please? I'm not sure I quite understand what is involved and how it works. Thanks.

Wing incidence
 

Luke,
I ran a search of wing incidence and nothing showed up for the Corsair. The wing is built with washout about 1.5 if I remember. If you set the wing and stab incidence +2 the plane should be more of a floater. Pete

TF F4U Corsair - 2 Questions
 

On the stall strip: F4U-1D and later models had a 6" long piece resembling angle iron, attached to right wing just outboard of the machine guns. It has attached so that the point of the angle faced forward. The idea was to get the right wing to stall a little quicker, thereby offsetting the tendancy for the left wing to stall first.

Re: Wing incidence
 

That's about what I put in my wing tips. I would go for it Pete, my Royal has +2 on the wing and stab. They fly so nice and look so good with the tail high in the air, you'll love it. How hard will it be to modify the TF kit? Lots to change in the wing saddle?

Luke

TF Corsair
 

I just want to know why I built the TF Corsair instead of the Brian Taylor one?. LOL DUH ME!!..I'm thinking Taylors is a lot more scale!.. and probably flies great also.?. BobH.

TF F4U Corsair - 2 Questions
 

I'm thinking the same or bigger! Next time :D Pete

TF F4U Corsair - 2 Questions
 

Don't look at the Ziroli, it has all of the same problems! I'm not talking to the guys who are happy with "it looks like a Corsair to me and flies great", and the Ziroli is all that, but if you know how a Corsair is really supposed to look then you won't be happy. I bought the Ziroli plan thinking that I could use it, but after much study, no way! To much to change. I always say, why redesign the wheel? I'll just go where it has been done better.

Luke

TF Corsair
 

Rocketman.. I would deff. go larger the next time.. Taylor has a nice 83incher that Bob Holman sells... BobH.

TF F4U Corsair - 2 Questions
 

JimoCooper,

I talked to a full-size AT-6 Texan pilot last year at the Gathering of Corsairs. Standing in front of Marine's Dream, we started talking about Corsairs and I asked him what that thing is on the outboard side of the machine guns on the leading edge of the right wing. He told me it was to help prevent tip stalls.

I don't know the aerodynamics of it, but it's true for the full-size Corsairs and, according to you, it's also true for our scaled down models. Cool!

Here's a picture of the one on Marine's Dream...

New wing incidence
 

Here is a pic of +2 wing incidence. The difference is 3/8 in. down at the TE. Look any better? Sorry for it being upside down. Pete

TF F4U Corsair - 2 Questions
 

Pete I was under the impression that you were going to leave the trailing edge alone and move the wing deeper into the fuselage? The problem is the belly pan, it don't fit the way the wing is and if you lower the trailing edge further this would only make it worse. Am I right or am I right.... or am I right!?? :D


Luke

TF F4U Corsair - 2 Questions
 

Does TF's giant corsair have the same problems as the Gold Edition?