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This is a 6 minute video made by MIT in the 1960 that demonstrates the value of streamlining round shapes on aircraft. At about 3:15 it gets interesting (at least in my opinion)
https://www.youtube.com/watch?v=ftq8jTQ8ANE&t=113s
Today I stumbled across an article with a mathematical formula that enabled me to quantify the pounds of drag that tail wires create on the Patrol. It gives credit to “EAA Aircraft Design†Vol. 3, Copywrite 1970, page 53. (To support the horizontal and vertical stabilizers, the Patrol uses four 1/8†diameter tail wires with a total length of 15.1 feet.)
http://www.jackbhart.com/firefly/pdrag.html
Here is what the calculations revealed.
11.46 pounds of drag is created by tail wires made of 1/8†stranded cables.
9.63 pounds of drag is created by tail wires made of 1/8†solid round steel.
A mere 0.72 pounds of drag is created by Streamlining the 1.8†wire with a 2.5 : 1 airfoil ratio.
The horsepower required to over come that drag…
One needs 4.28 hp to overcome the 1/8†stranded cable tail wire.
One needs 3.59 hp to overcome the 1/8†solid round tail wire.
One needs 0.26 hp to overcome the streamlined tail wire.
Nice to have some quantitive figures after watching that video for the first time a few years ago.
Brooks Cone
Patrol #303
https://www.youtube.com/watch?v=ftq8jTQ8ANE&t=113s
Today I stumbled across an article with a mathematical formula that enabled me to quantify the pounds of drag that tail wires create on the Patrol. It gives credit to “EAA Aircraft Design†Vol. 3, Copywrite 1970, page 53. (To support the horizontal and vertical stabilizers, the Patrol uses four 1/8†diameter tail wires with a total length of 15.1 feet.)
http://www.jackbhart.com/firefly/pdrag.html
Here is what the calculations revealed.
11.46 pounds of drag is created by tail wires made of 1/8†stranded cables.
9.63 pounds of drag is created by tail wires made of 1/8†solid round steel.
A mere 0.72 pounds of drag is created by Streamlining the 1.8†wire with a 2.5 : 1 airfoil ratio.
The horsepower required to over come that drag…
One needs 4.28 hp to overcome the 1/8†stranded cable tail wire.
One needs 3.59 hp to overcome the 1/8†solid round tail wire.
One needs 0.26 hp to overcome the streamlined tail wire.
Nice to have some quantitive figures after watching that video for the first time a few years ago.
Brooks Cone
Patrol #303
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