Once certified, always certified?

pilotod

Pre-takeoff checklist
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Is there ever a point in time when a certified plane can be decertified so that any changes made do not have to follow the certified rules?
 
Yes. If you want to change something radically from the type certificate, you can apply for an Experimental certificate to perform the radical mods(beyond a supplemental type cert).

There are significant limitations to the Experimental certificate when doing this.
 
The other point is the FSDO has to grant you the experimental status, which usually requires that you are intending to pursue an STC.
 
Which is a damn shame, because letting certified planes go experimental would be a great way to rejuvenate GA.
 
The other point is the FSDO has to grant you the experimental status, which usually requires that you are intending to pursue an STC.


And surrendering the standard airworthiness certificate.
 
And surrendering the standard airworthiness certificate.

That's no big deal. Once converted to experimental, it can (and must) be returned to its previously airworthy state and be given its standard airworthiness back.

So for example, you have a plane used for photo missions. It gets turned experimental so that you can chop a hole in it for the camera. When you sell it, it gets returned to normal and sold.

The issue that's been discussed for years is the idea of owner experimental, which would be great but I don't see the FAA allowing to happen anytime soonm
 
I doubt that cutting a camera hole for photography would qual for an EXP cert. That would be done on a 337 unless you wanted to cut the hole in the main spar(lol)! Now, if someone wants to mount a pair of Bonanza wings on a C-210, that would require an EXP cert.
 
I doubt that cutting a camera hole for photography would qual for an EXP cert. That would be done on a 337 unless you wanted to cut the hole in the main spar(lol)! Now, if someone wants to mount a pair of Bonanza wings on a C-210, that would require an EXP cert.


Pretty much. Cut holes for antennas...

They usually only go into experimental when they need to operate the aircraft to show compliance with regulations that compliance can't be proven otherwise.
 
A DAR has the authority to exchange a Special Light Sport airworthiness certificate for an Experimental Light Sport. And you don't need a reason, many owners have done it.
 
A DAR has the authority to exchange a Special Light Sport airworthiness certificate for an Experimental Light Sport. And you don't need a reason, many owners have done it.


Why do they do it and what are the concequesnces?

Assuming if the DAR is light sport authorised?
 
I doubt that cutting a camera hole for photography would qual for an EXP cert. That would be done on a 337 unless you wanted to cut the hole in the main spar(lol)! Now, if someone wants to mount a pair of Bonanza wings on a C-210, that would require an EXP cert.

I'm not sure what Mari's experience is, but I've talked to several photo plane operators who have "EXPERIMENTAL" on the side, and said it had to do with that. Often some other changes were made, too.

But, different operators and FSDOs may handle it differently.
 
Why do they do it and what are the concequesnces?

Assuming if the DAR is light sport authorised?


SLSAs have some strange limitations for alterations. The one I worked on was converted to ELSA because there was no longer a manufacturer to support it.
 
when i was flying photos we had a 337 for a camera hole in the baggage area of the 172 but when we flew with the camera strapped to the strut of the 182RG we were in the Restricted category.
 
I'm not saying you can't design a camera port that would go so far as to qualify for an STC, based on an EXP cert under development, I'm sure there are/were; but I am saying that the overwhelming majority of camera ports are done on 337 and the FAA never/rarely gets involved(unless it's a total hack-job).
 
although the shop did so many belly hole 337's on 172's that the FSDO basically told us to get an STC or a new FSDO.
 
Back to the OPs question, the mod has to be pretty substantial to qual for an EXP cert. Camera port notwithstanding. Putting a Chebby and PSRU in a Malibu would qual for an EXP.
 
FAR 21.191
Experimental certificates are issued for the following purposes:
(a) Research and development. Testing new aircraft design concepts, new aircraft equipment, new aircraft installations, new aircraft operating techniques, or new uses for aircraft.
(b) Showing compliance with regulations. Conducting flight tests and other operations to show compliance with the airworthiness regulations including flights to show compliance for issuance of type and supplemental type certificates, flights to substantiate major design changes, and flights to show compliance with the function and reliability requirements of the regulations.
(c) Crew training. Training of the applicant's flight crews.
(d) Exhibition. Exhibiting the aircraft's flight capabilities, performance, or unusual characteristics at air shows, motion picture, television, and similar productions, and the maintenance of exhibition flight proficiency, including (for persons exhibiting aircraft) flying to and from such air shows and productions.
(e) Air racing. Participating in air races, including (for such participants) practicing for such air races and flying to and from racing events.
(f) Market surveys. Use of aircraft for purposes of conducting market surveys, sales demonstrations, and customer crew training only as provided in § 21.195.
(g) Operating amateur-built aircraft. Operating an aircraft the major portion of which has been fabricated and assembled by persons who undertook the construction project solely for their own education or recreation.
(h) Operating primary kit-built aircraft. Operating a primary category aircraft that meets the criteria of § 21.24(a)(1) that was assembled by a person from a kit manufactured by the holder of a production certificate for that kit, without the supervision and quality control of the production certificate holder under § 21.184(a).
(i) Operating light-sport aircraft. Operating a light-sport aircraft that—
(1) Has not been issued a U.S. or foreign airworthiness certificate and does not meet the provisions of § 103.1 of this chapter. An experimental certificate will not be issued under this paragraph for these aircraft after January 31, 2008;
(2) Has been assembled—
(i) From an aircraft kit for which the applicant can provide the information required by § 21.193(e); and
(ii) In accordance with manufacturer's assembly instructions that meet an applicable consensus standard; or
(3) Has been previously issued a special airworthiness certificate in the light-sport category under § 21.190.
 
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Ok, so pretty substantial and something that meets FAR 21.191. If a plane gets a new engine that is not the original then it could be reclassified as experimental. Bear with me because I don't use the exact aviation language. The new engine could also fall under the other option to remain certified if the engine has an STC? Is that sorta close?

In a 172, what would be the least expensive way to convert the certified plane to an experimental (camera hole thoughts not included)? I'm just curious why more old planes don't leave the certified category.
 
Its pretty difficult to take a certified aircraft and make it experimental. If you are trying to get an STC approved, is one route, ie.. wanting an STC that you can sell to other people, or exhibition, the most common and least use restricted method is what is generally referred to as the 51% rule, you have to show to administrations satisfaction that you built or commissioned the build of 51% of the aircraft. which is the experimental amateur built section. You could copy an existing aircraft such as a Cessna 150 and use some peices from other 150's as long as you exceed the 51% of building it yourself. Lots of homebuilts use pipercub landing gear and wings, such as the Grega GN-1 did because you could find those parts everywhere. Taking a cessna 150 into experimental is going to cost you big dollars though, at least that's the why i understand it.


Ok, so pretty substantial and something that meets FAR 21.191. If a plane gets a new engine that is not the original then it could be reclassified as experimental. Bear with me because I don't use the exact aviation language. The new engine could also fall under the other option to remain certified if the engine has an STC? Is that sorta close?

In a 172, what would be the least expensive way to convert the certified plane to an experimental (camera hole thoughts not included)? I'm just curious why more old planes don't leave the certified category.
 
Ok, so pretty substantial and something that meets FAR 21.191. If a plane gets a new engine that is not the original then it could be reclassified as experimental. Bear with me because I don't use the exact aviation language. The new engine could also fall under the other option to remain certified if the engine has an STC? Is that sorta close?

In a 172, what would be the least expensive way to convert the certified plane to an experimental (camera hole thoughts not included)? I'm just curious why more old planes don't leave the certified category.

See the list above your post? Look at the ones prefixed 'operating'. Cause that's what you want to do, I presume is to 'operate' an EXP plane like a 172? If you want to air race, or train crew, or some other type of EXP action, that is very restricted. You typically need to get permission from the FAA for every flight outside the section on 'operate'. For those, you need to show that you built it(or 51% of it), which puts it in the 'substantial modification' category.

Are you getting the theme? The FAA doesn't want to have owners change a few trim pieces, take the plane out of it's standard TC and call it an 'EXP' plane.
 
Cool. I looked at the process way back on a type cert plane too. It was just way, way too much hassle to try getting out from under the thumb of the FAA on cert planes.
 
Cool. I looked at the process way back on a type cert plane too. It was just way, way too much hassle to try getting out from under the thumb of the FAA on cert planes.

Why not just get a non standard (experimental) plane? :dunno:
 
Experimental Armature Built get out of a lot of regulation but not everything.

I still balk looking at a C177 throttle from McFarlane at $440 vs an RV6 throttle from them at $165...

The parts for newer "in production" aircraft like the Corvallis can be EXTREEMLY high and there are no aftermarket sources.
 
Ok, so pretty substantial and something that meets FAR 21.191. If a plane gets a new engine that is not the original then it could be reclassified as experimental. Bear with me because I don't use the exact aviation language. The new engine could also fall under the other option to remain certified if the engine has an STC? Is that sorta close?

In a 172, what would be the least expensive way to convert the certified plane to an experimental (camera hole thoughts not included)? I'm just curious why more old planes don't leave the certified category.
The simple answer is that the FAA doesn't allow the airplane into Experimental category merely on owner whim. There must be a purpose for the conversion... as others have posted, it must be performed as part of a Reseach and Development effort, or as part of a marketing survey, etc.

There isn't a one-size-fits all "Experimental" category. You're probably thinking of homebuilt aircraft, where the owner gets substantial freedom to make changes and maintain the aircraft themselves. However, these aircraft are awarded their Airworthiness Certificates "For the purpose of operating an amateur-built aircraft."

Your modified 172 would not qualify as an amateur-built aircraft, so you'd have to fit one of the other purposes. You could certainly claim that the modified 172 would be exhibited, or used for Market Research, or act as a test bed for Research and Development, or even raced. These (and several others) are all approved operations under Experimental.

However...and here's the bugaboo... you have to prove to the FAA that this is the purpose the aircraft will be used for. In your application, you will have to describe, quite specifically, the modifications to the plane and how they tie into your stated purpose.

Finally, if you manage to leap all these hurdles and convince the FAA, there are two other things to overcome. The first is the Operating Limitations. These are given to you by the FAA, and they describe what you are allowed to do with your Experimental aircraft. For amateur-built aircraft they're pretty simple...but they can be quite complex for other types of Experimental aircraft. The Operating Limitations may prohibit the carriage of passengers, and will probably restrict the operating area of the aircraft. Your experimental 172 may not be much fun if you can't fly your family and can't fly more than 100 miles from your base.

The operating limitations will probably specify who is allowed to work on the aircraft...and in in the case of your Experimental 172, they'll probably require you to use a licensed A&P.

The other thing that'll bite you is the fact that the Experimental airworthiness certificate is not permanent. It has to be renewed at intervals, typically yearly. "Renew," in most cases, means "Repeat the original application." The fun thing is, the FAA person who gets it may not be the one you used last time. He may look at it and say, "This is nuts, I'm not approving this." And then you've got a worthless airplane until you find an inspector who WILL sign it off.

Experimental Amateur-Built and Experimental Exhibition both are generally easier, and don't have as much problems. I have a friend with a Fourier RF-5B motorglider with an Experimental Exhibition certificate, and his life is about as simple as mine with an Experimental Amateur-Built certificate.

But the process is designed to PREVENT folks from converting certified airplanes to Experimental for personal use. I knew a guy who developed a Chevy V-6 conversion and got a 172 licensed Experimental for a test bed. He had yearly hassles with the FAA come renewal time, and, like someone else mentioned, he was required to convert the plane back into standard configuration when he was done.

Ron Wanttaja
 
Its pretty difficult to take a certified aircraft and make it experimental.

Experimental Amateur-Built yes, Experimental Exhibition, no. There are lots of factory aerobatic airplanes in the Exhibition category to allow for non-STC'd mods. I'm doing it with mine right now to run a non-TC'd/STC'd prop. Although I was also told by the FSDO that there are some Cessnas out there running around in the EAB category which were inappropriately given "approval" to do so. They're cracking down on these types of situations.

And if you move to Experimental Exhibition, don't necessarily plan on being able to easily move it back to Standard. It's not just a conformity inspection. The local FSDO inspector told me, "The reason it's hard to move back is because you would have to prove that the aircraft / engine were not subjected to any unusual stress and conditions. You would have to provide documentation to support this. A DER would have to get involved to come up with this information. By the time you pay for all this, you could buy another Pitts."
 
The other thing that'll bite you is the fact that the Experimental airworthiness certificate is not permanent. It has to be renewed at intervals, typically yearly. "Renew," in most cases, means "Repeat the original application." The fun thing is, the FAA person who gets it may not be the one you used last time. He may look at it and say, "This is nuts, I'm not approving this." And then you've got a worthless airplane until you find an inspector who WILL sign it off.

Ron Wanttaja

This is a common misconception and has been repeated in this thread. There are cases where a standard TCDS has been forsaken for a permanent EXP TC. Of course, as mentioned the hoops are long and varied, but should the 'experimenter' succeed in putting a Chebby engine and PSRU on his trusty 172 and show that more than 51% of the aircraft was 'substantially modified'(I think that's the wording), it can qualify for operations under an amateur built EXP TC.

Common - no, possible - yes.
 
I'm not sure what Mari's experience is, but I've talked to several photo plane operators who have "EXPERIMENTAL" on the side, and said it had to do with that. Often some other changes were made, too.

But, different operators and FSDOs may handle it differently.

None of the photo ships I flew (maybe 10?) were experimental. They all had 337s for the hole. These were big enough holes that some of the cables had to be rerouted.
 
This is a common misconception and has been repeated in this thread. There are cases where a standard TCDS has been forsaken for a permanent EXP TC. Of course, as mentioned the hoops are long and varied, but should the 'experimenter' succeed in putting a Chebby engine and PSRU on his trusty 172 and show that more than 51% of the aircraft was 'substantially modified'(I think that's the wording), it can qualify for operations under an amateur built EXP TC.

Common - no, possible - yes.

The "experimental" clause has be abused so bad the FAA had taken the stance that almost no case qualifies for converting a certified plane into the experimental catagory..... Darn shame too as some really novel ideas could blossom.... It had got the the point people were wanting to dissasemble a Cessna and rebuild it one rivet at a time and claim it was their " one of a kind" experimental just to change catagories...:mad2:
 
The "experimental" clause has be abused so bad the FAA had taken the stance that almost no case qualifies for converting a certified plane into the experimental catagory..... Darn shame too as some really novel ideas could blossom.... It had got the the point people were wanting to dissasemble a Cessna and rebuild it one rivet at a time and claim it was their " one of a kind" experimental just to change catagories...:mad2:

The failure in your argument is that the plane in the example was disassembled and rebuilt one rivet at a time. My statement used the words 'substantially modified' and I used the example of a Chebby and PSRU in the proverbial 172. Two different statements.

However, I agree that the FAA has put the kibosh on standard cert to EXP for most all cases.
 
Yes. If you want to change something radically from the type certificate, you can apply for an Experimental certificate to perform the radical mods(beyond a supplemental type cert).

There are significant limitations to the Experimental certificate when doing this.
...starting with a 6-month limit (renewable once for another six months) before either an STC or field approval for the mod is obtained, or the aircraft must restored to its originally-certified condition, or the aircraft is grounded.
 
...starting with a 6-month limit (renewable once for another six months) before either an STC or field approval for the mod is obtained, or the aircraft must restored to its originally-certified condition, or the aircraft is grounded.

..Or, a permanent EXP-AB certificate is issued to the contraption, under the same rules as any other EXP-AB -- thing(I hesitate at this stage to call it an aircraft). But it's been done, and there are planes on the registry. Breezy comes to mind.
 
..Or, a permanent EXP-AB certificate is issued to the contraption, under the same rules as any other EXP-AB -- thing(I hesitate at this stage to call it an aircraft). But it's been done, and there are planes on the registry. Breezy comes to mind.
Breezy isn't a modified certified plane -- it's a compilation of various parts from various aircraft and other sources.
 
Breezy isn't a modified certified plane -- it's a compilation of various parts from various aircraft and other sources.

Uh - no. The orig Breezy was built up from a damaged Colt or J4 or something. They used Piper wings, tail, flight controls, Conti certified engine(the one used on the Piper). In fact, I think they even used the front and back seats from the J4, which was a single in front and a kind-of buddy bench in back. All other bits were 'substantially modified' from the original J4/Colt or whatever it was they used. It is in fact, a 'substantially modified' Piper J4/Colt, consisting of more than 51% built by the experimenter. In every case the homologation of what the OP is asking about by going from a cert TC to an EXP plane.
 
just the wings i believe
The Breezy used a set of Piper PA-12 wings and a factory new Continental C-90-8 engine with a special pusher crank. The original propeller was still being used after 800 hours and the engine was on only its second set of spark plugs. With an empty weight of 698 pounds, the prototype would consistently out perform other Breezys. Carl did much of the welding on the airplane himself. The ten gallon fuel tank, which Carl also made, lasted the entire time the Breezy was flying.
http://www.breezyaircraft.com/about.html
 

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