Warbird Information Exchange

I'm guessing this is one of the XF4U-5 Corsairs, .50 cal. wing guns, cloth wing and pre 1947 insignia.

Chin scoop vs. cheek scoops?
Did the new engine for the -5 (P&W 2800-32W) require the new cheek scoops or was it more for aerodynamic purposes?

http://collections.naval.aviation.museu ... n=16000013

Regards,
Mike

I believe these engines actually got the induction air feed to the supercharger/ carb from different sources depending upon altitude.
At TO the air fed through the wing root openings. At higher altitudes the cowling inlets fed the air to aux supercharger, then to the intercooler, and then to the carb, then to the main supercharger into the cylinders. They even had ADI, an alcohol/ water mix injected into the fuel/air charge to cool it some more to prevent detonation.
Rich

I meant the difference between the -4 chin and -5 cheek scoops. What drove the change, engine design or aerodynamics?

Here's a pic with the differences between the F4U-1 & F4U-4.

Regards,
Mike

From what I understand, there were three XF4U-5's and all were based on F4U-4's. The one in the photo would be either BuNo.97296 or BuNo.97364. Pretty cool shot, and the first I've ever seen of an XF4U-5 too!

_________________
Rob Mears
'Surviving Corsairs' Historian
robcmears@yahoo.com
http://www.robmears.com

Nice image and wonder is there more on that site?

Photo looks like it was taken on the Chance Vought ramp in Stratford, CT before the move to Texas.
Jerry

_________________
"Always remember that, when you enter the ocean or the forest, you are no longer at the top of the food chain."

I like the way it looks.

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Curtis Block

I've seen too many airplanes destroyed by the term "Static Restoration."

The -32W in the -5 has two massive superchargers which are positioned 90 deg to the crankshaft on either side of the accessory case. The cheek inlets were the inlet ducts feeding each supercharger.

When Dave Burnap had his -5 in the early nineties, we did some work to it. When this engine is running one the ground, you can hear the whine of the superchargers during a run-up. Very problematic and difficult to start in cold weather though...

Howard has a -32W in one of his hangars- I will see if I can learn to upload pictures.

Ashley

Thanks for the info.

What I'm still trying to get at is wether P&W said "heres our -32W, use it as is" or did Vought say " hey P&W, we want to use cheek scoops for aerodynamic reasons what can you do for us?"

Was the -32W used in any other a/c?

Regards,
Mike

With the side inlets of the superchargers, the cheek inlets were the most expedient way of ducting inlet air. I am fairly sure that the -32W was designed specifically for the -5 installation to meet goals of high altitude performance.

The layout of inlets was likely dictated by the installation or as engineers call it- "Design with Constraints".

Most of the -5's flying have had the -32W replaced with a CB series 2800. Sure makes for easier maintenance behind the engine with all of that room.

AE

The engine dictated the need for the air inlets, whether they were through the wing roots of the -1, the chin scoop of the -4, or the cheek scoops of the -5. As the engine horsepower increased, and the engine required more inlet air, and larger intercoolers, the inlets were increased in size and moved to places that could accomodate them. So, with the -18W engine, the wing roots of the -1 just were not big enough.

The -32W engine is an "E" series engine, and was designed just for the -5. Removing the auxiliary superchargers from the -32W, turns it into a -30W, for the F8F. Incidentally, this engine has a "pto" type drive, that I believe was designed in for a commercail application, such as cabin pressurization.

The airframe designers determined the design and location of the scoops, yet worked hand in hand with their counterparts at Pratt & Whitney, throughout the design and development of both the engine and the airframe. Don Jordan was the powerplant engineer at Vought, and was responsible for mating the R-2800 to the Corsair. The information I am relaying here is from a personal interview we did with him in our hangar a few years ago. He also explained his design to increase the power of the Corsair by aiming the exhaust stacks in just the right manner to add thrust. If I recall correctly, it was about 200 horsepower.

I suggest Graham White's book on the R-2800, it contains a wealth of information on the subject.

_________________
Craig
http://www.connecticutcorsair.com
F4U-4 Corsair Restoration

Does anyone know what series of CB the flying F4U-5's have? I know the CAF Corsair has a CB3 (single-stage supercharger) and the Convairs, DCs and most other commercial 2800-powered aircraft either have CB16s or CA18s, so I'm kinda curious as to what other models are still available.

BTW, someone help me clarify this. What's the difference between the CB and CA series? I thought that the CB had a dual-stage supercharger and the CA had a single stage, but I'm not sure anymore and can't find any confirmation online.