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jws3

Shortening a Chest Strap

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I believe the answer is: Contact the manufacturer. AC 1052e (I m not at me loft to read it) says, approximately, that a repair of this nature depends on whether it is already classified as a major or minor in recognized treatises/sources, such as Poynter, or the Parachute Rigger Handbook; and if it isn't, ask the manufacturer of that H/C if they will allow a Senior Rigger to shorten it. Some mfgs may say OK, some may not.

In short, major or minor is pretty much as it is defined in the recognized treatises, with the most recent one (The Parachute Riggers Handbook- an FAA publication) prevailing over older treatises.

I don't have the Parachute Riggers Handbook in front of me to see if it covers shortening a chest strap. If it does cover it, it will tell you if it can be done by a Senior Rigger.

Even so, AC 1052e still allows the manufacturer to define the chest strap shortening to be considered a major or minor repair.

I'm guessing that most manufacturers would allow a Senior to do it.

Opinion:
In my opinion, the discussion of what is a major or minor repair as presented in AC1052e is an intelligent and common sense approach. It recognizes the body of knowledge in the Poynter Manuals, the FAA's Parachute Rigger Handbook- the PRH, and other recognized sources and addresses the realities of the difficulties such rigging decisions. My view is that the AC1052e approach is far better than making a list of repairs with a major or minor designation. Yes, I realize that Poynter and the PRH designations of repairs constitute de facto lists, but for shortening a chest strap and some other repairs not listed, allowing the manufacturer to make that decision on their own product is a good default.

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Per the PRH:

Quote

TITLE: 7.3.2 Lower Leg Strap Shortening
NUMBER OF PAGES: 2
APPLICABLE PRODUCTS: All harness configurations.
DESCRIPTION: Shortening of the lower leg straps.
AUTHORIZED REPAIRMEN: FAA Master Parachute Rigger
MATERIALS: 5-cord nylon thread—color to match original
MACHINES: Heavy-duty harness machine—Singer 7-33 or equivalent 5-7 SPI
EQUIPMENT:
Seam ripper or scalpel
Marking pencil
Ruler
Hot knife



No chest strap procedure, so this is the closest match. Therefore one could put 2 and 2 together and suggest master is probably recommended for the chest too. At least, that is how I would interpret it.

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tdog

Per the PRH:

Quote

TITLE: 7.3.2 Lower Leg Strap Shortening
NUMBER OF PAGES: 2
APPLICABLE PRODUCTS: All harness configurations.
DESCRIPTION: Shortening of the lower leg straps.
AUTHORIZED REPAIRMEN: FAA Master Parachute Rigger
MATERIALS: 5-cord nylon thread—color to match original
MACHINES: Heavy-duty harness machine—Singer 7-33 or equivalent 5-7 SPI
EQUIPMENT:
Seam ripper or scalpel
Marking pencil
Ruler
Hot knife



No chest strap procedure, so this is the closest match. Therefore one could put 2 and 2 together and suggest master is probably recommended for the chest too. At least, that is how I would interpret it.



While published by the FAA this is actually one manufacturer's opinion. But once it's written by a contractor and published they publish it, with out any peer review or consensus, the FAA considers it a source for questions and the 'right' answers for test questions as well as a reference for inspectors. You have to parse what is simply wrong, opinion and fact.

Some will tell you to rely on the manufacturer and others will tell you that many manufacturers are giving illegal statements about who can do what. Both will tell you that's what the FAA will tell you.

Have fun and keep your local inspector happy.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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Hi tdog,

Quote

MATERIALS: 5-cord nylon thread—color to match original
MACHINES: Heavy-duty harness machine—Singer 7-33 or equivalent 5-7 SPI



This assumes that all chest straps are turned back and sewn with 5 cord; and that is simply wrong. I have seen certificated rigs in which nothing is turned back; merely wrapped with Type 3 and sewn with 'E' thread.

This is just another example of what is wrong with that document.

Jerry Baumchen

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JerryBaumchen

Hi tdog,

This is just another example of what is wrong with that document.

Jerry Baumchen



Well, considering the document is silent to chest strap shortening, you really can't say it is wrong procedurally... The OPs question was master or senior, not design. The chest strap replacement and leg strap shortening sections both require master, so one could extrapolate a master rigger should follow the original design for that harness container, following manufacturer specs, while doing the work...

And, I knew my post was gonna stir the pot, everyone complaining the PRH is not perfect.... But I don't see anyone calling Poynter asking for the rights to do a MAJOR rewrite of his work, bringing his manuals up to date, and putting it in the public domain as an FAA guidebook... So as it was once said, " everyone complains about the weather, but no one ever does anything to fix it.". :ph34r::ph34r::ph34r:

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With a certified harness. The work should be done with the same materials and construction techniques as the original. Otherwise this should be an alteration.

The fact that one manufacturer does it one way and it would probably be sufficient does not take away from the fact that it is a change to the original way the manufacturer designed it. There is no minor or major alteration just an alteration which is a master rigger privilege.

The manufacturers have different ways of constructing there harness and containers but I think a reasonable rule of thumb I was told by my DPRE would be if you are doing work on the harness then its probably a master rigger work item (I think the exception is replacing Velcro on harness).

If you have a master rigger ticket then you would be ok to make the repair or an alteration.

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..... returning to the original INTENT of the regulation: FAR 105.4064 Alterations of the auxiliary [reserve] parachute. .... B. Harness .... The harness is considered to be part of the auxiliary [reserve] parachute. .... May be altered by a master rigger ... any alteration that affects the strength or operation of the auxiliary parachute ...

............................................................................

Bottom line, FARs consider altering a chest strap an alteration, because if done poorly the chest strap might fail, the user fall out of the harness and misery ensue.
A common error would be falling to fold and sew the best strap end to prevent it from accidentally disconnecting from the buckle. Some chest strap ends can be zig-zagged on a Singer 20 U sewing machine, while others need to be sewn with 5 cord routed through a (class 6 or 7) harness machine. The finished alteration or repair must copy the materials and stitch pattern originally installed by the factory. Only master riggers, major lofts and factories invest in huge harness machines.
Alterations and major repairs are only supposed to be done by master riggers.

As for people whining about Poynter's manuals being out-dated or The FAA PRH containing a few minor errors .... may I suggest a third alternative: Eric Fradet's "Manuel's du materielle d'au jour d'hui." Fradet's manual is beautifully illustrated and clearly written - in French. A few years back, Eric offered me the opportunity to translate his 600 page manual into English. How many of you would pay for a 600 page rigging manual?

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RiggerLee

If it could be done I would like to read it. And I'd buy it, assuming the price was not rediculas. Say under $100.

Lee



..............................................................

The only way to keep the price under $100 is to publish the book electronically.
Next question is how to compensate me for the hundreds of hours to translate technical documents from French to English.

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I'd pay as well - Quite frankly Poynters is very dated and although there are a lot of things that still apply, there is also an tremendous amount that is irrelevant and highly unlikely to see.

Publishing electronically also has the ability to update regularly. If the document was up to date and could include additions for country specific regulations then I think it would be incredibly useful.

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First crack at it goes to the manufacturer. If they say minor then it trumps the FAA rigger handbook and poynter. Many rigs use a bartack to terminate the chest strap.

c. Major or Minor Repair Determination. When there is a question about whether a particular repair is major or minor, follow the manufacturer’s instructions. In the absence of the
manufacturer’s instructions, riggers should use the FAA’s Parachute Rigger Handbook (FAA-H-8083-17) and Poynter’s Parachute Manual Volume I and II as guides. If the procedure
calls for a master rigger, it should be considered a major repair. If the procedure allows for a senior rigger, it should be considered a minor repair.

There ya have it.

-Michael

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And certainly let us know what the manufacturer says.

As my DPRE told me, when getting confirmation from a manufacturer on something like this make sure you keep the communication to cover yourself and that you have the name of the specific person who provided the information.

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Cool. I sent UPT an email asking about it and I'll post the answer I get. I feel like the most likely response is that it's a major repair or alteration, requiring a master rigger. I'm a senior rigger and if I had a sewing machine that could do harness work, I'd be tempted to just do it myself. I don't have one though.

Edit:
Just got a response from them. They say anything on the harness is supposed to be done by a master rigger.

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I've got a MC-4 that I use for demo's. The chest strap and belly band have nothing terminating the end of the strap. It looks like the straps were just cut with a hot knife and left that way. The chest strap isn't unusually long or short, but the belly band is very long, so i don't think they have been cut by just anybody, I think they were originally like this.

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Another way to look at it is that any change that results in a factory approved configuration is a repair - either major or minor. If the chest strap doesn't come in that dimension from the factory then it's going to be an alteration so it automatically falls into master rigger territory.

-Michael

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hackish

First crack at it goes to the manufacturer. If they say minor then it trumps the FAA rigger handbook and poynter. Many rigs use a bartack to terminate the chest strap.

c. Major or Minor Repair Determination. When there is a question about whether a particular repair is major or minor, follow the manufacturer’s instructions. In the absence of the
manufacturer’s instructions, riggers should use the FAA’s Parachute Rigger Handbook (FAA-H-8083-17) and Poynter’s Parachute Manual Volume I and II as guides. If the procedure
calls for a master rigger, it should be considered a major repair. If the procedure allows for a senior rigger, it should be considered a minor repair.

There ya have it.

-Michael



No where NEAR this simple. The FAA handbook is one manufacturer's opinion (the one who wrote it.) NOT the FAA's. Although now inspectors rely on it and some maintain it's the only allowable way to do anything.>:( Poynter's is as much tradition as logical or regulatory interpretation, although again the FAA relied on it in the absence of anything else. Of course very little of Poynter's is original. And there are some inspectors and DPRE's that will tell you the manufacturer's instructions cannot and does not trump an FAA interpretation.

Some of the above I agree with and some don't. And rather than a bar tack many chest straps end with 5 cord harness machine straight stitches.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

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