Fuselage Drag

[aerohead]

We might as well have a dedicated thread for this topic as it has implications for the Motorcycle forum (I'll put it over there as well).
All the images will be from 'AERODYNAMIC DRAG',by Sighard Hoerner (of Fieseler/Junkers/Messerschmitt),'invited' to the USA under 'OPERATION PAPERCLIP',self-published 1951.
The 1st image is self-explanatory from its title.(there will be additional images to come)

Here is a second table showing canopy drag

Here is a 3rd table for gun turrets which are germane to canopy desing

[kach22i]

I don't understand, do the numbers on the top line titled "CONFIGURATION" have something to do with length, or width?

Found this on the general topic.

Drag Coefficient Lookup for Fuselage Screen

[aerohead]

Originally Posted by kach22i

I don't understand, do the numbers on the top line titled "CONFIGURATION" have something to do with length, or width?

Found this on the general topic.

Drag Coefficient Lookup for Fuselage Screen

*The dimensions remain constant
*Only the features of the fuselage vary,from 'bare',to fully festooned with canopy opening with pilot,windscreen,and engine.
*The Cds are a function of Reynolds number (read along the bottom ),as an aircraft fuselage is large enough the be affected by skin friction more so than pressure drag.
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It appears that your fuselage tool is for supersonic aircraft,based on the nose architecture.
We'd want the blunt nose for 'normal' driving velocities.

[freebeard]

Drag coefficients of several fuselages...

Perhaps 8.4 through 8.7, referenced in Figure 8.2, in turn reference other figures?

The 'Drag Coefficient Lookup for Fuselage Screen' accepts only two parameters. The next one needed would be the position on Length of the maximum diameter. Their MSPaint illustration does not inspire confidence.

[aerohead]

Originally Posted by freebeard

Perhaps 8.4 through 8.7, referenced in Figure 8.2, in turn reference other figures?

The 'Drag Coefficient Lookup for Fuselage Screen' accepts only two parameters. The next one needed would be the position on Length of the maximum diameter. Their MSPaint illustration does not inspire confidence.

The configurations are only the four depicted.The difference in Cds varies as the Reynolds numbers below each column.

[aerohead]

I've added two additional drag tables from Hoerner.
The 3rd image is for gun emplacements/turrets but is germane to canopy design.
You'll notice that in every instance,the fully boat-tailed structure delivers the lowest drag to the fuselage.Biomimicry.

[kach22i]

I like that second table you added on canopy drag - thanks.

[gone-ot]

Just imagine how much drag these two (APS-45 upper; APS-20 lower) radomes created on the Lockheed USN EC-121!

[aerohead]

Originally Posted by Old Tele man

Just imagine how much drag these two (APS-45 upper; APS-20 lower) radomes created on the Lockheed USN EC-121!

There's a fella named Roger who comes in here at Copy-Pro regularly.Roger flew all the Connies in the USAF then went on to become a commercial airline pilot.He said that turbulence was the big issue.
The first iteration of 1951,with the 53-foot flying-saucer radome was the worst for rudder and elevator authority.He said they didn't fly worth a ---t.
The minimized dorsal and additional belly pumpkin seed was really a big improvement.

[gone-ot]

I spent my entire Navy career flying in those Navy Connie's. The later-model EC-121 planes had the center vertical stabilizer "locked" because they were literally "in" the turbulant wake of the upper radome...the original models had all three rudders operative, however.