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Old December 31st 19, 03:41 PM posted to rec.aviation.soaring
Dan Marotta
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Posts: 4,601
Default Locating Transponder Antenna on top of the fuselage instead ofunder it.

I believe drag is related to the square of the speed.Â* How often do you
fly your glider at 250 kts?

On 12/30/2019 3:52 PM, wrote:
O
And since you asked about different style 1/4 wave dipoles. The rods, blades etc. should all behave the same from a RF viewpoint. They are effectively the same internally. Rods/single attach point style antennas may be easier to attach/mount on curved surfaces, but have higher drag than a blade if that small drag worries you. I've also seen A&Ps recommend the rod style so that if you do manage to crunch it will bend and hopefully do less damage to the fuselage/finish.

Transponder rod antennas spec drag at .41 lbs at 250 MPH and blade antennas at .09 lbs at 250 MPH. That seems to be a big difference but anyone have a comment to what this measures in the gliding world?


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Dan, 5J