Switch from E-AB to LSA?

[bflynn]

Simple question - is it possible? I've searched and cannot find anything that confirms it, but can't find anything that says it's impossible either.

It might help to give a specific scenario. The kit is a Zenith CH-650, 2 seats, ~650lbs empty weight. My understanding is that the kit can be built as an E-AB and reach speeds faster than 120 kts. OR the prop can be changed out to trade speed for climb and the speed will be truly limited to 120 kts and the aircraft will meet LSA standards.

So - planning for some hypothetical future where medical reform doesn't pass as part of the FAA Reauthorization Act and I have a need to fly sport, could I change the E-AB into a sport plane by changing the propeller..and of course then fly with no medical. It's still an E-AB airplane but limited to sport capabilities, so it is a sport plane, right? Not really different than some of the small grasshoppers that are certificated aircraft but meet the sport standard?

[rwanttaja]

Simple question - is it possible? I've searched and cannot find anything that confirms it, but can't find anything that says it's impossible either.

It might help to give a specific scenario. The kit is a Zenith CH-650, 2 seats, ~650lbs empty weight. My understanding is that the kit can be built as an E-AB and reach speeds faster than 120 kts. OR the prop can be changed out to trade speed for climb and the speed will be truly limited to 120 kts and the aircraft will meet LSA standards.

So - planning for some hypothetical future where medical reform doesn't pass as part of the FAA Reauthorization Act and I have a need to fly sport, could I change the E-AB into a sport plane by changing the propeller..and of course then fly with no medical. It's still an E-AB airplane but limited to sport capabilities, so it is a sport plane, right? Not really different than some of the small grasshoppers that are certificated aircraft but meet the sport standard?
Not if the plane is already certified as an EAB. The Light Sport Aircraft definition in 14CFR Part 1 says, "Light Sport Aircraft means an aircraft...that, since its original certification, has continued to meet the following..." (Emphasis added).

It's legal if the plane hasn't already received its Airworthiness Certificate, but not if it it is a flying aircraft.

But...if you change the prop, no one in the world is ever going to make you switch back to the original and attempt to verify that the plane didn't make LSA performance limits with it.

Ron Wanttaja

[stewartb]

Take a lesson from Cubcrafters. Write an ops manual that limits power and speeds to meet the LSA requirements. Make the gross 1320#. Leave it in E-AB and fly it in the Sport Pilor category.

[Dana]

The plane will always be registered E-AB. E-LSA registration is only for planes built from a LSA certified kit. If the plane falls within the LSA limits (1320 gross, stall and max speed), then it can be flown by a sport pilot. But if the plane has ever not fallen within the LSA limits, you can't lower the limits (i.e. reducing the gross weight or putting on a flatter prop) and then fly it as an LSA. It needs to meet the LSA limits from day one.

[bflynn]

Not if the plane is already certified as an EAB. The Light Sport Aircraft definition in 14CFR Part 1 says, "Light Sport Aircraft means an aircraft...that, since its original certification, has continued to meet the following..." (Emphasis added).

So if I want a fast airplane and later need a sport airplane I cannot change the existing one into sport, I have to build a whole new plane.

Unfortunate

[Byron J. Covey]

So if I want a fast airplane and later need a sport airplane I cannot change the existing one into sport, I have to build a whole new plane.

Unfortunate

What documentation is there that indicates thet the E-AB does not meet the LSA criteria?


BJC

[rwanttaja]

What documentation is there that indicates thet the E-AB does not meet the LSA criteria?
That, of course, is where the fun part comes in. If it's a homebuilt, then it is, by definition, a unique aircraft. The FAA would have little basis to dispute the builder's claim that it meets the Light Sport definition. They could look at the engine and make sure there was only one (and a recip at that), make sure it didn't have a constant speed prop or retractable gear, snoop for third or fourth seats...but they'd have a hard time DISproving it was Light Sport legal. Even if they make you give them a ride, you can shrug off a high airspeed to gauge error. Us single-seat drivers don't even have to worry about THAT issue.

Ron Wanttaja

[Frank Giger]

The biggie is the gross weight allowed. If it's 1320 or less with a fixed prop, fixed gear, and only two seats, chances are it's LSA compliant, or could be argued as such (if the stall speeds and cruise speeds are also within limits).

[rwanttaja]

The biggie is the gross weight allowed. If it's 1320 or less with a fixed prop, fixed gear, and only two seats, chances are it's LSA compliant, or could be argued as such (if the stall speeds and cruise speeds are also within limits).
The point is, how does the FAA disprove it if you claim the cruise and stall speeds fall within limits?

Build an RV-8, build it as open cockpit, leave off the spinner and wheel pants, list the gross as 1320, and call it a "Fly Baby Mark 3." If the FAA *ever* ramp checks you, claim it's Sport Pilot eligible.
http://www.bowersflybaby.com/fbiii.jpg

Not that I advocate doing this, of course. No doubt if the FAA sees a flood of questionable cases, they'll try to implement some sort of enforcement system. But I don't think it'd be too easy to implement....

Ron "Why are all those Vans builders gathered outside my house with pitchforks and torches?" Wanttaja

[Dana]

I'm sure there are more than a few homebuilts with a stated 1320# gross weight that are regularly flying at a higher weight... just like many if not most "ultralights" weigh more than 254#. If it becomes an issue, which I doubt, they may come up with speed calculation charts (wing area vs. weight and HP) like the Part 103 appendices.

"Yes, I know it looks like an IO-540, but it's actually a homebuilt engine limited to 60 continuous horsepower."

[Frank Giger]

Of course we're agreeing with each other in different ways, Ron.

But it all comes down to when the aircraft was signed off on. For my gross weight I slapped a happy number down, one that I won't actually ever reach (or at least hope never to).

And all the V speeds are a big unknown at Pink Slip Time. There are some educated guesses, but they're all blank at hour zero.

My point was that once it's established, one shouldn't change the gross weight limits without running into a flag from the FAA refs. Heck, I know a guy with a FlightDesign CTLS that has been known to take off with full fuel tanks, two passengers, and the baggage limit and survived. It's almost like the FlightDesign folks stuck the number 1320 out there just to make the LSA requirements! And "cruise" is a fickle number to begin with. Va and "best cruise" for fuel efficiency are related, but only casually so. The rules for LSA compliant aircraft only say "cruise speed" and so it's firmly in murky water territory.

In many ways, my little Bebe is the reason for LSA rules. She's a big fat ultralight with a 12 gallon fuel tank.

[bflynn]

The Zodiac CH650 is legitimately light sport - depending on the engine, somewhere between 625 to 730 lbs empty weight, 30 gallon tanks with larger tank upgrade, plenty of useful load. The only variable factor is the speed. It can go 140 or it can go 120 depending on the prop.

It's a moot point. I'm on the verge of pulling the trigger on building but it will be a few years before I put a prop on it. Medical reform will be long past by then. If it passes I can build it fast, if not then I built it E-AB to LSA specs. If it passes later, I can change it later. About the only extra thing I have to do is add lights and even that is months to a year down the road.

Of course I've been on the verge of pulling the trigger for a while now.

[dljosephson]

Simple question - is it possible? I've searched and cannot find anything that confirms it, but can't find anything that says it's impossible either.

It might help to give a specific scenario. The kit is a Zenith CH-650, 2 seats, ~650lbs empty weight. My understanding is that the kit can be built as an E-AB and reach speeds faster than 120 kts. OR the prop can be changed out to trade speed for climb and the speed will be truly limited to 120 kts and the aircraft will meet LSA standards.

You might want to do some more research. The CH650 is a great airplane, but it would be really tricky to build one that weighs 650 pounds, and I doubt that you could reach 120 ktas in continuous full power level flight at sea level (the regs say nothing about cruise) with any practical engine. You're building the engine too, right? You get to decide what the maximum continuous power is. Frank Giger's comments are correct. Who's to say it goes more than 120?

[martymayes]

Of course I've been on the verge of pulling the trigger for a while now.

At least you're not trigger happy....:-)

[earldowns]

The Vc of the CH650 is 108 kts IAS. The Zenith definition of Vc is “The Maximum Structural Cruising Speed that should not be exceeded except in smooth air and only with caution.” Why are we discussing an IAS cruise of over 120 kts IAS?

[dclaxon]

My understanding is that no matter how fast the aircraft may be capable of going, if the builder writes into the operating limitations that the maximum cruise is 120kts, then the limits is 120kts. That may or may not fall within the intent of the law, but I'm reasonably certain that there is a large number of LSAs that have been done that way.

And as for how it's registered, given the limitations put on LSAs I see absolutely no benefit of registering a homebuilt as an LSA. And it makes no difference in who can fly it, if it's registered LSA, E-AB, or even a real certificated aircraft, if its weight, speed, complexity, etc fall within the Light Sport definition, it can be flown by a Sport Pilot.

I don't claim to be an expert, and I may be wrong about tis, but that is the way I understand it.

Dave

[rwanttaja]

My understanding is that no matter how fast the aircraft may be capable of going, if the builder writes into the operating limitations that the maximum cruise is 120kts, then the limits is 120kts. That may or may not fall within the intent of the law, but I'm reasonably certain that there is a large number of LSAs that have been done that way.
Aircraft certified as Special Light Sport (SLSAs) are required to gain FAA approval, and this would include showing supporting documentation that the aircraft meets the performance limits. Experimental Light Sport Aircraft (ELSAs), *at the time the type received FAA approval* must also be able to prove compliance. This FAA approval process is simplified over Part 23 aircraft, but it does still exist.

Once an owner gets his or her mitts on an ELSA, there's nothing stopping them from adding streamlining, changing prop pitch, putting on a bigger engine, etc. that would allow exceeding the 120 knot limit. Technically, the plane would not be in compliance, but in reality, the FAA is unlikely to check.


And as for how it's registered, given the limitations put on LSAs I see absolutely no benefit of registering a homebuilt as an LSA. And it makes no difference in who can fly it, if it's registered LSA, E-AB, or even a real certificated aircraft, if its weight, speed, complexity, etc fall within the Light Sport definition, it can be flown by a Sport Pilot.

You can only register a kit as Experimental Amateur-Built (EAB) if it meets the 51% rule, and you can only register a kit as a Light Sport if it complies exactly with the aircraft the manufacturer used to gain SLSA certification. These two sets don't necessarily overlap, as kits for Experimental Light Sport Aircraft are allowed to be in a greater state of completion and thus may not comply with the 51% rule.

But there are aircraft that do; the RV-12 is one. Given my druthers, unless there were serious modifications I wanted to build in, I'd build one as ELSA. It's no difference to the original builder, since he or she can get a Repairman Certificate and perform the condition inspections on the EAB.

But it comes into play at sales time. The guy who buys the EAB RV-12 will have to either talk the original builder into continuing to perform the condition inspections, or hire an A&P. The person who buys the ELSA RV-12 can take a 16-hour course and can then do the inspections.

Ron Wanttaja