I made a preliminary calculations that my Max 3 has a drag of:

WING 0.134 sq ft

IND.D 0.008 sq ft

FUSE 0.125 sq ft ( + rudder...same wetted area coefficient 0.0027 )

W+B.I 0.012 sq ft

ELEV 0.031 sq ft

--------------------

ALL 0.310 sq ft

Total drag coefficient based 0n wing area in 0.0120

Total wetted area dragcoefficient is 0.0015 which can be considered phenomenal !

Previously only VmaxProbe had close to similar figures and P-51D Mustang 0.0040 ( AR-5 0.0034 ).

There is no drag by cooling ( like in P-51D ) and the gear ( since it is retractable ).

That is less than half of the drag of a 3 feet longer and 1.9 sq ft more fuse cross section possessing AR-5 record setter.

http://www.ar-5.com/condrag94.html

NOTION; The fuse and rudder being non lift producing may have a coeffient .0025 which would yield 0.116 sq ft drag and making total drag into 0.301 sq ft. That would be 34 % of AR-5 drag and enabling to reach AR-5 speed with only 26,65 hp engine ( 213 mph ). This sounds plausible since Vmax Probe was calculated at 85% prop efficiency to go 240 mph with 50 hp. We have nowadays props that can go up t0 90% efficiency. It is also possible that my wing can be made with a lot less drag with some new foil ( instead the NACA I had as a basis ). Big wing will be serving the landing and take off behaviour...so I won't reduce the size to keep the landing more loading at 65 kg/m2. Wing being 0.120 sq ft drag the whole equation can be 0.287 sq ft ( 33 % of the AR-5 ). You see what I am getting here..checking if I could go 218+ mph with just 22 hp engine enhanced with nitrous oxide ( in theory it seems possible since with 90% efficient prop Max needs only 20 hp now with a super wing and fuse..nitrous will enhance the power output easily by 8-10 prosent ).

Who is going to say pushers have no advantage when it comes to drag issues ?

Also packing everything in a really small and yet compact size pays off.

You don't have to trust my estimate for the speed...just check the hp with 90% ( or even the 85% ) prop efficiency and use my calculated 0,31 sq ft for drag:

## 2009-03-01

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I was forced to make corrections to this topic since I saw that B C used dragcoefficient 0.0029 for a non lift producing fuselage of AR-5 which is more bulged than MAX III fuse.

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