Water mellon with and without helmet drops "test"

[Matteo V]

A helmet has less drag in water that a head with hair or even shaven.

Why? How? Any reference to back this bold claim up?

[grigorib]

If you have a watermelon for a head….

[bragnouff]

Why? How? Any reference to back this bold claim up?

Where's logic and reason when we need it ????

[downunder]

Where's logic and reason when we need it ????

In the melon

[iriejohn]

Where's logic and reason when we need it ????

For chrissake don't start him off otherwise there'll be a cascade of multi thousand word posts

[FredBGG]

A helmet has less drag in water that a head with hair or even shaven.

Why? How? Any reference to back this bold claim up?

Very simple. Take that fake hairy chest your wear and glue it under your twin tip and see how much slower your board it..... just kidding.

Speed boats have any algae/weed growth under the hull removed.
Holes in hamlets and the air venting/air injection effect that is used on some racing boats.

Both reduce drag.

[Kamikuza]

Do the same experiment into water with a G-meter, at increasing speeds?

I'll let you go first.

Sure, I'll go first and drop the helmet into water with a G-meter in it. Didn't realize that was such a scary thing for you.

[Kamikuza]

Do the same experiment into water with a G-meter, at increasing speeds?

Potential Darwin award entry - head first / no hands dive with & without helmet... with video ideally

That would be the "clown dive" known as a Gorilla. Done it off the 1m diving boards, but that's my limit. Staples off the 5m, can-openers off the 10m, no worries.

You could also just put the G-meter in the helmet...

[bragnouff]

Why? How? Any reference to back this bold claim up?

Very simple. Take that fake hairy chest your wear and glue it under your twin tip and see how much slower your board it..... just kidding.

Speed boats have any algae/weed growth under the hull removed.
Holes in hamlets and the air venting/air injection effect that is used on some racing boats.

Both reduce drag.

OK, different surfaces can reduce drag when volume of the object is constant. However in the case of no helmet vs helmet, you go from the volume of your head to the volume of the head + helmet. It's a significant difference in volume (maybe 20% ?). My hypothesis is that this extra volume is creating more drag than whatever surface aspect is capable of reducing. Assuming we're in the real life context of diving/punching through the surface of water, and not bouncing on it at 100mph, of course.

Because this isn't exactly clear to me, I was asking for clarification/references/...

[GraemeF]

Not sure what to derive from this thread other than a recipe for watermelon lasagne from Iriejohns Mrs (That's a surprise to me that a woman even married him), but as to advice from a long termer who has always been against Helmets being mandatory for watersports, purely on a freedom of choice basis. I rode Motorcyles prior to 1967 when the law came in enforcing helmet use and we often rode without locally but chose to use them only for distance or if we were likely to be opening up. I waterski raced but only used the helmet either in training or actually racing when speeds were between 50 and 80 mph back then and you wouldn't pass scrutiny without a helmet and it had to be vented to avoid bucketing. I rarely used one windsurfing except on a tandem when racing and I do use one now kiting by choice since I did smash head first into the promenade wall without one and have slightly reduced motor skills as a result.

But after all this I still feel it should be your choice wether to or not, unless it's some form of competition and some one could get sued because of your actions to others or yourself.

Oh and if you're baldylocks you can look a tad younger in a helmet.