Hardhats

[Witch]

Yesterday, Mike-my I.P.-brought his helmet to show me.

 

Sherman, set the Wayback to two weeks ago.

 

I mentioned to Mike that I was looking around for a hardhat, probably a refurbished SPH4, and told him about an idea I had a while back of installing comms in a motorcycle helmet I have. He told me tha the has an SPH4 and he'll bring it in some day. As for my idea of installing comms, he thought it'd be good to do but that the weight wouldn't be all that good because the motorcycle helmet is a bit heavier, even an open face.

 

So, back to yesterday. He shows me his hardhat, and it's lighter than my helmet by quite a bit. Upon closer inspection, I notice that the shell seems awfully thin to withstand a hard impact. The liner also seems a little inadequate for side impacts, as in nothing over the ears except the earphones. This got me to wondering if these things are crashworthy.

 

I know motorcycle helmets are designed to absorb impact and abrasion from concrete and asphalt and as a result built beefier, but might not the same be needed for a helo helmet?

 

In the end, I'll more than likely get the SPH4, but I'm wondering if it'll offer adequate protection for the biological computation device located inside my skull?

 

Opinions?

 

Later.

[TaIk2Kevin]

Send it in to mythbusters so they can test it

[volition]

Yea!!! I'd liked to see that on mythbuster's too!!

[Superman]

Hey Witch,

 

If you know any kids that play Little League, get one of their batting helmets, set it next to the SPH4, not much difference between the two. Plug the ear holes, mount a visor on it and you have a flight helmet! In fact, I think some of the older helmets were made by the same companies.

 

Soloed yet? or are ya snowed in out there?

 

Fly Safe

Clark

[FUSE]

I hope your a small guy if your flying a 22. I've been a motorcycle rider my entire life, well since I was 7. Both my parents have taught the MSF Safety course my entire life as well. So I'm real big on safety. So the first thing I did when I started flying and knew I was going to continue my training was get a helmet. I found the best one I could, A Gentex HGU-84, put the hush kits in, dual visor, lip light, everything except for ANR. Well at this point I had about 1400 invested. Then wouldn't you know it, I couldn't wear it in the 22. I was ALWAYS hitting my head on the frame. I mean constantly. It would give me such a massive headache because of the constant hitting of the head and the awkward angle I had to keep my head at to minimize how much I hit it. I ended up buying a Lightspeed headset and now I'm in heaven flying.

 

I tried to sell the helmet on e-bay, not one bid. I had a buy it now price of 700. Figured half price someone would buy it, nope... Now it's just sitting on a shelf collecting dust..

 

Oh btw, I'm 5'10" and 200lbs.

[Linc]

By yourself a nice set of DCs or something comparable. More comfortable and probably costs less.

 

...unless you're really planning on crashing. In crash sequences, the SPH-4B has been shown to not be effective at reducing forces below the 200G limit which is a threshold for brain injury.

[Witch]

Oh, I have the H10-30;bought it in 86. I replaced the airplane cord with a helicopter cord. I also wrapped some foam and cloth over the mic to make a windscreen. Looks like crap, but it works

 

Superman, Yeah I soloed...in the snow. Well not really. It only snowed for one day and I took the bus to work. The solo was a bit anti-climactic. I mean yeah I'm flying alone, but so what, I did the same thing 20 years ago. At least they didn't cut out the back of my shirt this time. Ruined my favorite Berlin shirt. At least I was able to get another.

 

One thing I noticed; with Mike in the cockpit and in a hover, we pull 23 inches of manifold pressure. By myself, it's 19"mp. That means Mike is only 4". That's as far as I'll go.

 

 

Linc, how is the protection above the 200G limit?

 

Starting to look at SPH4's

 

Later.

Edited December 12, 2006 by Witch

[Linc]

Sorry, the limit is 150G to prevent concussive injury. There is another study that evaluates the Kevlar helmet soldiers wear during airborne operations that references the 200G range. The SPH-4 seems to not quite protect in all ranges to below the 150G range. The HGU-56/P is demonstrated to be much, much better. Again, this information is only valid if you are considering crashing a likelihood, otherwise, a headset is a cheaper and more effective alternative.

Impact Attenuation

A primary function of the rotary-wing aviator helmet is head protection during mishaps. Head impact injury is the leading cause of permanent disability and fatality in Army rotary-wing mishaps (Shanahan, 1985). Head impact protection is accomplished by proper helmet design, a design which provides a protective outer shell and sufficient stopping distance between the shell’s outer surface and the skull. The purpose of the protective shell is to resist penetration from sharp or jagged impact surfaces and to distribute the load over a greater contact area. The head impact velocity in survivable helicopter crashes has been estimated at 19.6 feet per second (5.97 meters/sec) through computer simulations and analysis of sled test results. This number is based on the potential flail velocity of the occupant’s upper torso (Desjardins, et al., 1989).

 

Human head impact tolerance is an area of continuing research. The USAARL has recommended a test head form threshold of 150 to 175G, depending on the impact location. See Table 7.1. A review of performance specifications for other helmet applications (i.e., motorcycle, bicycle, equestrian, fixed-wing aviator, etc.) reveals a range of thresholds ranging from 200 up to 400 G. The USAARL recommended value for the headband region (175G) is based on the concussion threshold to linear accelerations, not on skull fracture, fatality, or rotational acceleration thresholds. The USAARL recommended value for the earcup and crown regions (150G) is based on the risk of basilar skull fracture concomitant with impacts to those areas and the high frequency of occurrence in Army helicopter crashes (Shanahan, 1985).

Link

 

And here are some studies that discuss the SPH-4. Caution, all three links are pdf documents that are technical in nature and may take a while to download.

[500E]

Had a near mis ( 20ft )with a large Buzzard this week looked like it was going to take P2 screen out, hard port and climb!!! to dam close. I am ordering a helmet, even if it only to hold the visors

Remember the old adage your money or your life? I prefer the money and what about blade strike on helmet there are a few stories about people alive due to wearing a helmet .

[Gunner]

HGU-56's have a much thicker styro liner than the SPH-5's and SPH-4's... That means more protection. I mainly wear a helmet in case of birstrikes or a blade coming through the cabin when things start to go bad...

 

I have one I will sell you that is in awesome shape if you are interested....