Home made aero helmet

Mach 1.3

Refined estimate: Mach 2 to Mach 3, depending on which value of the autoignition temperature of paper you use, which to some extent depends on the duration of exposure as well as the composition, and assuming that the blunt leading edge is essentially at the stagnation temperature of the flow.

Obviously both the helmet and the rider's head will be ripped apart by the aerodynamic forces before heating becomes the key problem, but it's as well to understand correctly the order in which problems need to be addressed :-)

I'm really struggling to wank to that reflectoporn

nah yu can definitely seeee hjs willy

...but it's as well to understand correctly the order in which problems need to be addressed :-)
Wouldn't his tyres melt or tubes explode first?

Probably, but this thread is about his helmet, not his rubber:

nah yu can definitely seeee hjs willy

(With the previous Freddie Mercury references in mind) however fast he's going it'd have to be pretty quick(silver)

Home made aero skin suit?

Just wax all over instead?

(With the previous Freddie Mercury references in mind)

I'm burning through the skies Yeah!
Two hundred degrees
That's why they call me Mister Fahrenheit
I'm trav'ling at the speed of light
I wanna make a supersonic man out of you

Home made aero skin suit?

Passing by like Lady Godiva

Wax or use plasti dip..

Or latex paint
http://i2.squidoocdn.com/resize/squidoo_images/250/draft_lens32module1371278photo_1319604526bodypaint-king.jpg

I'm burning through the skies Yeah!
Two hundred degrees
That's why they call me Mister Fahrenheit
I'm trav'ling at Mach 2 or 3
I wanna make a supersonic man out of you

ftft

Whilst we're re-writing Queen lyrics, 'Mister Kelvin' has a nice ring to it.

All the aerodynamic heating papers I've looked at are from American sources, so they use Rankine rather than Kelvin. Also, we're in the area of 1000R to 1500R, not two hundred.

"I'm burning through the skies Yeah!
Five hundred degrees
That's why they call me Mister Rankine
I'm trav'ling at the speed of sound
I wanna make a supersonic man out of you"

This is true for some body shapes at some altitude, roughly at the top of Everest.

I know someone who was attacked on Everest recently. Fuckin' Sherpas, how do they work (at that altitude)?

http://www.stopabductions.com/

^lol

Only one failure since 1998!

I appreciate the Mach debate but I think people are missing the point, he will reach flight and then time-travel, long before he can achieve sonic boom

^Pretty close.

I couldn't resist having a go any longer. I peeled of the masking tape, got into my kit, clipped in and set off.

For the first run I didn't plan any special route, I just went for a ride around.
My initial thoughts of the helmet were that it was comfortable, stable, visibility was good and that it felt like it was doing its job. After a little while I also realised that my head was getting pretty warm. The lack of ventilation might be an issue on longer runs, but essentially the project was successful. I was pleased.

A bit further down the road I was spinning along in top gear (53x12), thoroughly enjoying the speed. I was flying along the road and suddenly I took off and was flying through the air.

Literally.

A man from the forum's favourite team of bad drivers had decided to turn right, right across my path, but he misjudged my speed and did not get past in time. I had a fraction of a second to react. I don't think I eased off at all and I certainly didn't apply the brakes. Straight into the side of the black people carrier I went. At full speed. This launched the bike, helmet and I right over the top. I remember next, lying on the ground on my back looking up at the bystanders starting to stand around me and say things like 'Oh my god, are you ok?', 'Don't try and move'. Mostly I was thinking, ffs, this is rather annoying. Amazingly the helmet was still on my head and was pretty much unscathed just the tail having been clipped. I distinctly remember taking it off at that point and putting it down by my side so I could lay my head back on the ground in exasperation.

When the driver walked up I knew it was him before he said anything. That look they have: thirty something, tired, unshaven and wearing a cheap suit. I said to him 'You're the last person I want to see right now'. After some moments of contemplation and assessing my condition I decided to get up and I asked after my bike. I hobbled over to the pavement and sat down to have a look at my bike. There was no way I could ride it home. A friendly lady put her arm around me whilst I got over the shock, one gentlemen handed me his card, saying 'If you need a witness' and the driver offered to give me a lift home. As we were about to go a paramedic arrived on a motorbike. My nature is such that, if I'm not gushing blood or don't have a bone sticking out of a limb I don't like to trouble emergency ambulances, so I said no thanks.

After I got home I decided that I probably should get the once over from a medic after all. My right knuckle in particular was not in a very good state. In anticipation of the usual wait in A&E I got changed. I left the crippled bike and the helmet at home and rode the trusty steel bike to the hospital. By the time I was seen I was finding it quite difficult to walk. They checked me over and told me that luckily I had, aside from some surface wounds, only some bad sprains and strains.

By the time I left the hospital all the adrenaline that must have flooded my body upon impact with the car and had enabled me to ride to A&E had completely dissipated. Every step was extremely difficult and I could only walk at snail's pace. I managed to get on my bike and pedalling very lightly I made some progress home. This was much faster than shuffling along on foot, but I had to stop after a while because although I could roll along ok, going over the slightest of bumps was agony and I couldn't lift off of the saddle. I continued home on foot and eventually I heard a black cab approaching and managed to hail it.

Since then, proof of concept having been achieved, the helmet has sat on a table in the corner of my room collecting dust.

Following the enthustiastic respose to what I have shared with you, I think it is probably time to dust it off and either actually get into time trialing or raffle it off or donate it to a poor time trialist with the same shape head as me.

This project involved a few firsts for me. It was the first time I made something out of papier-mâché (I probably did something in primary school, but I don't remember it), it was the first time I did any spray painting and it was the first time I made a personal injury claim. The papier-mâché I was pretty pleased with, the painting I am extremely pleased with and the claim although I would rather have not had to learn about this was succesful. Before I started this thread I thought any second helmet would be made in a similar way, but with fibre-glass. I haven't used that before and fancy having a go. However this would be even more of a problem than the spray painting; I don't fancy having resin fumes and glass dust in the same room as my bed. One suggestion I think quite sensible is vacuum forming, probably using ABS plastic. I have no doubt of the effecacy of the helmet and I believe this to be the result of four main things: the sheer length of the tail, the absense of any vents, the enclosed underside and not having any padding and thus a frontal profile not much wider than the head.

Although I didn't build into the helmet any saftey aspect I like to think that in those moments when I was in the air I was thinking 'Oh no, my helmet. After all that time and effort...' and that somehow this made me do something to protect the helmet and thus my head.

So you really went riding at high speeds with a piece of paper on your head. You could've been dead man, buy a normal helmet and throw this in the bin.

/\
/\
+17 for true grit and services to the Absurd
life would be as dull as a bog roll inner tube if it weren't for visionaries/lunatics like Polka Dot
if I have a son, I may call him that

So you really went riding at high speeds with a piece of paper on your head. You could've been dead man, buy a normal helmet and throw this in the bin.

What if his paper helmet saved him? What then, eh!?