P-47 nose

[JS P-47]

I am wondering that if anybody put a spinner cone on the nose of a P-47, how fast would the plane fly? And is there a mathematical solution?
I am 12 years old and I like to know these things.

 

[FLYBOYJ]

If it was justifiable the manufacturer would have done it. I don't think it was so much omitted for speed but more for engine cooling.

 

[model299]

There have been other aircraft where the manufacturer DID try a spinner. In almost all situations, it ends up being removed for a variety of reasons including weight, simplicity, easier maintenance. Most of the time, it boiled down to the fact that it really didn't make any difference when it came to speed. .

A good example of this is the Grumman F4F. Here's a picture of an early version with one in place. As I'm sure you know, wartime active duty Wildcats never used them. (AFAIK)

Good question!

 

[davparlr]

A great question and I am not sure I have seen a satisfactory answer. Many XP aircraft like the XP-60, 62, 72, XF7F, XF8B, and XF2B, all had spinners. In addition in Germany, the Fw-190, and Ta-152 (although this one had a liquid cooled engine) had spinners and the British Sea Fury also. Also, a few Japanese like the Zero, had spinners.

In general, in the US, with its powerful radials, decided the extra cleanness was off set by complexity, I guess.

 

[A4K]

Would agree with all, especially with Joe on the engine cooling.

Most British radial engined aircraft did have spinners, usually of small diameter, so there must have been atleast a slight benefit in performance if fitted. This includes some aircraft of US manufacture like the Brewster Buffalo.

(Btw, just looked through one of my books, and the prototype F-6F Hellcats also had large spinners)

 

[wuzak]

In general, in the US, with its powerful radials, decided the extra cleanness was off set by complexity, I guess.

I don't think spinners count as being "complex". Basically they are a cover which forms part of the ducting shape for the cowling - and theoretically is needed for teh cooling system to work at its optimum.

However, practically speaking I think in most cases it was found to give negligible benefit.

Aircraft such as the Tempest II, Fury/Sea Fury and Fw 190 had ery tghtly cowled engines with louvres/slots rather than cooling flaps. Maybe there was more benefit for them.

 

[Shortround6]

In some cases the "spinners" actually helped ground cooling. They kept air from flowing back out of the engine cowling around the propeller hub rather than flowing through the cylinder baffles. A few planes were fitted with discs behind the propeller to do the same thing.

An awful lot was learned about how to cowl engines for lowest drag and best cooling in just a few years. In the late 30s a lot of the learning was by trial and error.

 

[FLYBOYJ]

I don't think spinners count as being "complex". Basically they are a cover which forms part of the ducting shape for the cowling - and theoretically is needed for teh cooling system to work at its optimum.

A lot more complex than you think. Depending on the designer, the spinner would produce specific airflow to achieve proper cooling so in many times a lot of thought goes in to design. Additionally the way the spinner is placed around the prop dome can go from being very simple to very complex depending on the size of the prop hub and the size and shape of the dome. In the GA world you are not supposed to fly certain aircraft unless the spinner is installed.

The spinner, also being a dynamic component must be balanced or else it will create vibration. In many cases it is difficult to repair a spinner should cracks form on it which is pretty common. I had a spinner come apart on an airplane I was flying, scared the crap out of me.

A spinner could be a very basic component that could become very complex depending on aircraft, propeller and what type of cooling is required.

 

[A4K]

Interesting info guys!

 

[rank amateur]

Just did a quick check and I would say the American industry had a tendency not to use spinners. Of all the radial engined militairy aircraft of WW2 only the A26, XF7F, XB28, P61, Constellation and SB2C have spinners. The first 4 being propelled by the r2800, the conny by the r3350 and the last by the r2600

 

[vikingBerserker]

In some cases the "spinners" actually helped ground cooling. They kept air from flowing back out of the engine cowling around the propeller hub rather than flowing through the cylinder baffles. A few planes were fitted with discs behind the propeller to do the same thing.

I always wondered what they (discs) were for.

 

[JS P-47]

Thanks all for the information! I'm off to some research.

 

[A4K]

Good stuff mate, and welcome to the forum too!