Fuselage tubing size - shoulder harness analysis

[Robert Lees]

Re: Fuselage tubing size - shoulder harness analysis

<snip>...Shoulder harnesses in a Taylorcraft will only provide so much protection and if your harnesses break the carry through you have more worries than you may realize. .... Tim</snip>+

In that we agree. If an impact is sufficient to deform the cross-tube to which a shoulder harness attaches, then a lack of shoulder harness probably would not make any difference. The human body is not very good at surviving extreme deceleration (sp) forces.

But any help in preventing injury during "minor" bumps must be welcomed.

Rob in Utah.

[Robert Lees]

Re: Fuselage tubing size - shoulder harness analysis

<snip> Proven statistical fact that many die trying to evacuate because they don't get their seatbelts off. </snip> Tim

This is worthy of a separate thread, of course, and in principle I can see that everyone would sensibly agree, due to the difference in seatbelt release design, but could you offer a source for the "proven statistical fact"?

Interestingly, and with no supporting evidence, I would suggest that most Europeans (who are now used to very-low-cost flying as compared with most Americans) are quite familiar with airline-style seatbelt release.

Rob

[astjp2]

Re: Fuselage tubing size - shoulder harness analysis

There was an NTSB report on the causes of lethality in aircraft accidents, many eye whitness reports included about removing seat belts in aircraft accidents. The report had a documentary film that included it along with improvements in aircraft design that has lead to a reduction in fatalaties as aviation has evolved. One big one was the DC10 in Iowa, one woman was an eye witness, reported that she could not get her mother's seat belt off and she parished because of smoke inhallation even though her daughter was able to egress.

[astjp2]

Re: Fuselage tubing size - shoulder harness analysis

Dave, why not use that engineering time to get a 74" metal prop approved for a taylorcraft with a C-85? That would be important to more people possibly than having an analysis on a shoulder harness installation that people have been doing for decades. Just food for thought. Tim

I support any engineer with the tools and knowledge to analyze to heart's content.

The learning is valuable and why expect that everyone will do the same things the same ways that I do?

[Guest]

Re: Fuselage tubing size - shoulder harness analysis

Dave, why not use that engineering time to get a 74" metal prop approved for a taylorcraft with a C-85? That would be important to more people possibly than having an analysis on a shoulder harness installation that people have been doing for decades. Just food for thought. Tim

Hi Tim,

Sure that's a good thing too but it is his time not ours and we spend our time as we want to spend it not so much as others would have us spend it.

My 35 years experience with engineers and being one as well is that they/we often dig into pet projects and it sharpens the wit and skills that are used later for other things.

Sometimes we just wanted to know how it "worked" often we solved some current problem.

I often if not always let my engineers explore an idea and also often got them to dig into other project that utilized those previously developed skills.

The prop sounds like a good project but I wonder if Terry Bowden is already on it? Seems like that applies to his STC.

Dave

[Hank Jarrett]

Re: Fuselage tubing size - shoulder harness analysis

One of the motivations for engineers is curiosity. We do an analysis because it is FUN and we just want to know what the number is. Sometimes it is just a Nerd thing. Leads to a lot of "discussions" that non engineers think are arguments. They aren't.

Hank

[Hank Jarrett]

Re: Fuselage tubing size - shoulder harness analysis

OK, not always. ;-)

Hank

[astjp2]

Re: Fuselage tubing size - shoulder harness analysis

I applied for the STC but I could not come up with the money to get the strain gauge analysis on the blades done. There was a guy in WA that wanted $10K just to put them on....and the analysis was extra...Tim

[Hank Jarrett]

Re: Fuselage tubing size - shoulder harness analysis

TEN THOUSAND DOLLARS to put on strain gauges!!!!! That is an OUTRAGE! Any university with an engineering program will have loads of students who have had Experimental Stress Analysis who can do it. Even I DID IT as a student! (years ago, but for that kind of money I can get someone with RECENT experience who is certified if needed)
Can we do it in the lower 48? MY company should be able to do it for a fraction of the cost.

Hank

[astjp2]

Re: Fuselage tubing size - shoulder harness analysis

Hank, those students do not have a DER to sign off on the analysis...that is why they can charge that much...Tim

[Hank Jarrett]

Re: Fuselage tubing size - shoulder harness analysis

Oh, I get it. The cost wasn't for the strain gauge test and analysis, it was for the DER sign off. I can't help much with that part.

Hank

[astjp2]

Re: Fuselage tubing size - shoulder harness analysis

Actually the strain gauges were 10K to start, the engineering was extra...but he could sign off on an STC data package. I would love to get an M74CK-0-43 prop legal on an 85, 90 and O-200...

[water007]

Re: Fuselage tubing size - shoulder harness analysis

So, if using the Wag part no. H-858, will I need any additional hardware to attach to the AC tubing? Do the end-fittings that come with those harnesses suffice, or maybe additional local hardware? I do have a skylight, so no overhead liner. Trying to figure this out w/o having my manuals (with my A&P) in hand, so I can order ASAP

[PA1195]

Re: Fuselage tubing size - shoulder harness analysis

Brief thread drift here in reply to a comment above re: propellers. I have a Field Approval for a Sen 76AK-2 via engine application and limits noted in TCDS 1P2 on my T-Craft's C-85, pitch not specified (it's 40). A multi STC might require more substantiation.

[Joe cooper]

Re: Fuselage tubing size - shoulder harness analysis

Brief thread drift here in reply to a comment above re: propellers. I have a Field Approval for a Sen 76AK-2 via engine application and limits noted in TCDS 1P2 on my T-Craft's C-85, pitch not specified (it's 40). A multi STC might require more substantiation.

I witnessed an accident involving a TCRAFT with student and CFI. The student lived with serious Injurys. The CFI died. Most who witnessed the crash on take off ( probable engine failure) and the way she died, concluded shoulder harnesses probably would have saved CFI and made his injurys less serious. He more or less was thrown into her as it crashed right wing down in a stall using her as an airbag so to speak. After WW2 shoulder harness should have been required. They have saved uncountable lives.