Building the first of a new type

[felixflyer]

Hi

As the title suggests, I am contemplating building a wooden aircraft that has not been built before. The design is complete and is based on an existing approved type.

Could somebody tell me what the process and likely cost would be to get this aircraft on a permit to fly once it is built.

I read in the LAA magazine about the Flitzer and the owner saying he would never go through that process again. Is it that onerous and expensive?

[ChickenHouse]

UL?
Experimental?
thought to go into production series?

[Floppy Link]

Start here...

LAA Guide (http://www.lightaircraftassociation.co.uk/engineering/TechnicalLeaflets/Building,%20Buying%20or%20Importing/TL%201.07%20Acceptance%20of%20New%20Designs.pdf)

...then add lots of cash and time. No guarantee of success either.

[FleetFlyer]

Build it as an SSDR if you can. You'll save yourself a world of pain with the LAA. Just build it under 300KG and with a stall speed less than 35kt.

[Jan Olieslagers]

What does "SSDR" stand for?

To original poster: take a look around at HomeBuiltAirplanes.com (http://www.homebuiltairplanes.com) and particularly for the Scots gentleman who has designed, built and flown a plane he calls the Iolaire, if my old memory still serves.

[FleetFlyer]

SSDR is Single Seat Deregulated. Its basically intended to allow competent people to design and build their own single seat microlight, however it allows anything that meets the stall speed and maximum weight requirements.

Any aeroplane produced under this regime is only inspected once when its finished. Its not subject to any design approval process. This approach clearly has pros and cons. You don't pay £2000 to the LAA to get a new type approved, and you can modify it without submitting paperwork to anybody, but on the other hand it opens the door to crazies who may build deathtraps.

There is some guidance on the LAA and CAA websites about this.

[Jan Olieslagers]

Thank you! I'll be a really accomplished aviator when I've mastered the last acronym - many years from now.

[Charles E Taylor]

Building the First of a New Type.


Your timing might be perfect to explore the new CAA "E" Conditions regulations.

These are specifically aimed at the encouragement of new designs without all of the attendant "Airworthiness" costs and complications.

http://www.caa.co.uk/docs/2907/20141117Exp%20Cat%20thematic%20consultation.pdf

I will be interested to see how you get on if you explore this route.


Good Luck.


Charlie

[felixflyer]

Thanks for the replies and the links. The research continues.

To clarify this will be done via the LAA. I don't think it will be allowed under the SSDR and I want it to be cleared for aerobatics.

I am interested in the 'external engineering' process really. I would like to know what level of expertise is required and how much could possible be done by myself providing calcs and using CAD and FEA tools rather than a sacrificial airframe etc.

[Genghis the Engineer]

I could probably spare a few hours to go through it if you need some pointers - it's a big complex business that doesn't lend itself to easy discussion on a bulletin board. Where are you?

FE is useful as a design tool, but I doubt very much that you'll get away with a new wooden airframe without a significant amount of structural testing. The variability in wooden construction, wood properties, etc. make physical testing essential. A full sacrificial airframe can potentially be avoided, by testing sub-assemblies and coupons then putting it all together mathematically.

By and large it's going to require a mixture of testing and hand calcs, FE won't be your best friend here once you're past the design stage - it's a design, not a certification tool.

The other obvious question - do you have an engineering degree, or something equivalent? Not essential, but the associated skillset will help a lot.

With regard to the new CAA E-conditions, it's obviously completely untested as yet, but I'd love to help make an E-conditions programme work, and would certainly meet CAA's definition of a "Competent Person" in that regard. LAA in general however, don't get hung up about specific qualifications however, they just want competence.

G

[cockney steve]

but on the other hand it opens the door to crazies who may build deathtraps. .... That's a bad thing? :}

Darwinism at work...live with it....or die, as you wish.

[Genghis the Engineer]

Surprisingly it's killed hardly anybody at-all.

Most likely, in my opinions, because the halfwits who would be killed trying to fly their own creations, generally discover very quickly that they are nowhere near clever enough to design and build an aeroplane at-all. So, they end up doing the sensible thing -that is buy something designed and built by a grow-up.

G

[Them thar hills]

"that is buy something designed and built by a grow-up"


That's no guarantee they won't roll their new wonderplane into a ball !

[9 lives]

An excellent resource for a prospective builder are the books suggested on this thread:

http://www.pprune.org/flight-testing/363780-flight-test-book-review-thread.html

If, upon becoming well familiar with a lot of these themes, the designer/builder feels confident to go ahead, then they are doing it "with their eyes open".

I have known many amateur builders, and among them, two who designed and built their aircraft. I never flew in either, but spoke at length with both builders. One was agreed by all who commented to be a design disaster, and flew only the one time. The other appeared magnificent, and the several hundred hours flying on it suggested it was a very worthy design.

But a caution (with no disrespect to the OP): The decision forces which come together to result in an amateur built plane usually include a desire for cost reduction. This is false economy, even if your design/build time has very low money value to you. Certainly excellent amateur built aircraft result from a labour of love, but that is not cost reduction, and now your "love" is flying = greater risk to it. This links to the next well know risk...

Builders throw themselves headlong into building, and let fly skills lapse. There is a natural resistance to now want to spend money and time renting someone else's plane, when "soon" you'll have your own. Then you do, and the flying skills you may have had, and deteriorated.

For this reason, there are regulations about the piloting experience required for first flights on amateur built aircraft. But, as an experience flight tester of GA aircraft, I can assure that a PPL with a few hundred hours on a 172 or PA-28 is not ready to fly initial flight testing on an amateur built, much less one of unproven flying qualities.

Builders must adopt a very serious attitude toward this, knowing that their pride and joy should be test flown by a very experienced pilot, and that they will need recent experience on something similar before they launch off.

I am a personal witness to a fellow wrecking his newly built Kitfox right in front of me on my home runway. He did not hurt himself, but the plane took a three year rebuild following his blatant flying error. As I flew him home, I engaged him as to his flying experience: 250 hours in 150/172, spread over the preceding 10 years, with only the rental recency minimums on the past few years. (So he met the minimums to fly his initial Kitfox flights, and did). One hour in the Kitfox with his taildragger buddy for familiarization, and his crash hour was his 7th on the Kitfox. That was a very expensive flight! (it was not insured).

Bringing an amateur built to flight will encompass many more factors than appear at the outset. They can all be managed, and overcome, but it will not be a cost saving exercise!

[Jan Olieslagers]

That's no guarantee

Agreed.
There's no guarantees anyway.
Not in aviation, neither elsewhere.
Except of course the two well-known certainties...

None of that is a valid reason for not judging and perhaps even taking one's own risks.

[Them thar hills]

FelixF


If you have plenty of determination and patience, go for it, via the LAA.
I know someone who did successfully design and build his own single seater, quite recently.


He is now well on with an o/d two seater, Rotax powered.


tth

[B19]

I would agree with you. You need have lots of flight experience to fly some home builds.


Someone built a P-51 mustang scaled down version at my home airport and the pilot/builder flew it once and never flew it again.


Said it was very unstable. CG limits must not have been right????


Good Luck:)

[colinc]

Hi,

Forgetting the issue of test flying, I thought it worth responding about building a new design.

The LAA does support amateur designers as part of it's organisational goals and there is evidence to suggest that it does deliver on that. Obviously though, to ask it to spend funds on investigating a design you have to be very committed yourself to stay the course and provide the necessary data to support the increasingly thorough review that gets carried out. If things go wrong, the lawyers will be all over them so don't expect a design to get signed off easily. I have been on the fringes of the process in trying to get a design approved that ultimately qualified as SSDR but I would warn you that it is not a trivial exercise.

Having said that, if you have a design that offers something special enough to warrant the work then you must contact LAA Engineering and have a discussion about it. There is no more effective way forward than that and contrary to the popular view, they will help you if you have a viable project.

Regards,

Colin