Having just completed a two week rebuild of the r/h wingtip and aileron of my Storch (towing accident)....I realised how rusty my knowledge was on the subject of materials.
Nestor Slepcev's build instructions (as original builder John Ashby discovered) were fairly minimal, so no real help there.
But, he did mention all rivets throughout were Monel.
This got me thinking why?
On my first build, a Sherwood Ranger, the build specified Monel in certain key areas. That seemed logical. But to use monel on ali to ali , relatively low structural strength areas, seems heavy and wasteful.
So when it comes to material grades...rivets and sheet...where or who is the fount of all knowledge.
How does a designer decide? Are there any fixed rules?
Homebuilt material selection...is it a black art?
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bencmaster
- Posts: 38
- Joined: Fri Jan 11, 2008 6:11 pm
Monel is normally specified for corrosion resistance together with quite good strength.
I'd take AC43 Chapter 7 as chapter and verse on hardware selection, as recommended by the LAA engineering department.
It can be found here.
I'd take AC43 Chapter 7 as chapter and verse on hardware selection, as recommended by the LAA engineering department.
It can be found here.
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Ernest Lear
- Posts: 22
- Joined: Tue Jan 08, 2008 9:32 am
“So when it comes to material grades...rivets and sheet...where or who is the fount of all knowledge.
How does a designer decide? Are there any fixed rules?” I try and answer your question.
Are there any fix rules? Yes. Sound Engineering calculations. Light aircraft have to be light. Weight must be kept to a minimum and at the same time, because someone going to fly in it, the structure must absorb all flying loads and stay in one piece when flown within its design parameters. The designer check each and every component used in his design, including all the rivets, Some area of the structure is lightly loaded. Lighter fixings will be adequate for here. But to ensure that the design is safe Stress Analysis of the aircraft parts are carry out after the forces on any particular part are know. Weight and Balance calculations check and rechecked after each components material or structural change is made due to these stress calculations until he satisfied his design is safe and fit to fly.
When it comes to building. The builder should follow the designer drawings including all the require specs quoted on all the materials and finish parts used. Change, large or small, are in fact redesigns and calling for further design calculations to prove the structure is still safe to fly. The answer to your question is :- The original or final designer is the fount of all knowledge for that particular aircraft.
How does a designer decide? Are there any fixed rules?” I try and answer your question.
Are there any fix rules? Yes. Sound Engineering calculations. Light aircraft have to be light. Weight must be kept to a minimum and at the same time, because someone going to fly in it, the structure must absorb all flying loads and stay in one piece when flown within its design parameters. The designer check each and every component used in his design, including all the rivets, Some area of the structure is lightly loaded. Lighter fixings will be adequate for here. But to ensure that the design is safe Stress Analysis of the aircraft parts are carry out after the forces on any particular part are know. Weight and Balance calculations check and rechecked after each components material or structural change is made due to these stress calculations until he satisfied his design is safe and fit to fly.
When it comes to building. The builder should follow the designer drawings including all the require specs quoted on all the materials and finish parts used. Change, large or small, are in fact redesigns and calling for further design calculations to prove the structure is still safe to fly. The answer to your question is :- The original or final designer is the fount of all knowledge for that particular aircraft.
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bencmaster
- Posts: 38
- Joined: Fri Jan 11, 2008 6:11 pm
Which , of course is all fine and dandy if that info is available.The original or final designer is the fount of all knowledge for that particular aircraft.
Thanks for this tip...Now that really does seem like good bedtime reading. Is it available in book form or just as a web download?I'd take AC43 Chapter 7 as chapter and verse on hardware selection, as recommended by the LAA engineering department.
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Graham Newby
- Posts: 21
- Joined: Thu Jan 03, 2008 11:00 am
Graham,Graham Newby wrote:You could of course buy it from your Association, the LAA!
Would that be like the "Aircraft Ignition & Electrical Power Systems" book as listed in the magazine but notable by its absence on the website?
Particularly annoying as the mag covered electronic ignition this month!
Rob Swain
If the good Lord had intended man to fly, He would have given him more money.
If the good Lord had intended man to fly, He would have given him more money.
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Guest
Hi - I'm Dave Dale, who runs the LAA Shop.Rob Swain wrote:Graham,Graham Newby wrote:You could of course buy it from your Association, the LAA!
Would that be like the "Aircraft Ignition & Electrical Power Systems" book as listed in the magazine but notable by its absence on the website?
Particularly annoying as the mag covered electronic ignition this month!
'AC43' is, of course, available online from the LAA shop, or via the Mail Oder pages in the mag. It's been in both, continuously, for the last 7 years, under its title 'ACCEPTABLE METHODS, TECHNIQUES & PRACTICES - AIRCRAFT INSPECTION & REPAIR'.
The "Aircraft Ignition" book went out of stock at the distributors in January, and has only just come back into stock. When a book becomes unavailable, even for a short time, I try to take it off the online shop until it arrives back in stock - this prevents any disappointment for customers. It can mean a book appearing, disappearing, and re-appearing on a regular basis, particularly with US-sourced titles.
It is, of course, less easy to remove a book temporarily from the magazine Mail Order pages, so the situation can arise where a book may be listed in the magazine, but not online.
By the way, a quick phone call to the office can often be productive!