[RV7Guy]

First, please no negative replies. I want to figure out how to do it, not why it can't be done.

It seems to me that the 40 hour Phase 1 requirement is antiquated. I'm not sure when it was established but I'm confident it was when Experimental aviation was still very much a science project. Now with so many prefabbed kits and clone type engines is there really a need to have the 40 hour requirement?

My thought is if your plane is a kit plane and uses clone type engine and proven propeller it should qualify for a 25 hour Phase 1.

The 40 hours would still apply if the engine is anything that began as an auto engine.

I'm willing to do the writing and submit the proposal to the FAA.

Thanks in advance.

 

[Ironflight]

It's a noble goal Darwin, and in fact, there is already work being done by folks on making Phase 1 more task-oriented (ie, complete these particular tests) raethr than hour oriented. You're right - one size does NOT fit all, and specifying hours is not an effective way of measuring how much testing has been completed. Many people just fly the same hour forty times - testing nothing, and wasting the effort.

These things CAN be changed and like I said - there are already efforts to get it done.

 

[jrs14855]

Phase 1

I'll break this down into two or more parts. I did my first EAB first flight in July 1964 but who's counting. In those days it was 50 hours for an aircraft with an engine that was type certificated. ZERO interest from the FAA on who had built the engine or worked on it. They simply did not care about the prop. Also they did not seem to care If one changed props after the completion of phase 1, which I did numerous times.
Aircraft that did not have a type certificated engine required a 60 hour phase 1. This included Lycoming GPU conversions IIRC. In that era a second FAA inspection was required to go to phase 2, and there was no builder condition inspection. Every year the FAA had to inspect the airplane.
I think the time requirement changed at the same time as the change that allowed condition inspections to be done by the builder.

 

[jrs14855]

Phase 1

Now lets look at Experimental Racing subcategory. I don't know what is currently required, but we all know that a lot of modification goes on with Racing aircraft, at least some of it doesn't get properly tested.
Without naming names, there was a certain rather well know Goodyear Midget racer that allegedly only had one short test flight before departing on a cross country to its first race several hundred miles away.
Now to Experimental Exhibition. I have not kept up with this at all for many years, but have not read or heard of any significant changes. In the 90's, when many high performance aerobatic aircraft were being imported, the "phase 1" requirement was five hours. Many of these, the Yaks and the Sukhois for example, did not have type certificated engines. There is also the issue that although many were built in factories, no two aircraft of the same model were exactly alike.
So the question, if a Yak 18 can be signed off to carry a pilot and three passengers after 5 hours of testing, why not an RV10 with type certificated engine?

 

[jrs14855]

Testing

Now a hypothetical: aircraft A has a factory new Lycoming and Hartzell prop. The "test pilot" cruises around for 25 hours, not really testing much of anything. This test pilot happens to be one of those who is terrified by the thought of going anywhere near Vne during his testing.
Aircraft B is a well proven design but built from scratch. It has a non certified Lyclone engine and a fixed pitch wood/composite prop, a prop design that has been built in large numbers and used by many other aircraft of the same type. The builder thoroughly tests the airplane for 10 hours. Everything is working perfectly, the airplane has been dive tested to Vne.
Airplane B has been more thoroughly tested than airplane A. Yet in the infinite wisdom of the FAA, airplane B requires 30 more hours of testing. This entire issue in FAA la la land nonsense.

 

[jrs14855]

Vne

The certification requirements for turboprop powered aircraft are slightly different than those for piston powered aircraft. My understanding is that the turboprops are designed to a slightly higher gust load requirement. However in the case of designs such as the Cessna Conquest I that are basically reworked derivatives of the piston engine Cessna 421, there is virtually no change in maneuvering speed, except as dictated by increased weight. Another result of this is that the turboprop has no airspeed yellow arc.
Yet the turboprops are routinely flown at Vne in smooth air. I have never encountered an operator or pilot that did not fly these aircraft at Vne.
So in testing an EAB that is a proven design, I have no problem testing the airplane to at least Vne and sometimes to 110% of Vne.
Anyone who signs off phase one without testing to Vne has skipped perhaps the most important test of all.

 

[jrs14855]

First, please no negative replies. I want to figure out how to do it, not why it can't be done.

It seems to me that the 40 hour Phase 1 requirement is antiquated. I'm not sure when it was established but I'm confident it was when Experimental aviation was still very much a science project. Now with so many prefabbed kits and clone type engines is there really a need to have the 40 hour requirement?

My thought is if your plane is a kit plane and uses clone type engine and proven propeller it should qualify for a 25 hour Phase 1.

The 40 hours would still apply if the engine is anything that began as an auto engine.

I'm willing to do the writing and submit the proposal to the FAA.

Thanks in advance.

I only have one issue, leave out the kitplane and come up with a reasonable definition of proven design. My built from scratch Pitts S1 was far superior to any Pitts ever built from a kit and any certified Pitts built by Aviat.

 

[awmuhs]

early flight accident stats

I wonder how hard it would be to catalog the accident statistics for the first 40 hours of flight time for owner built aircraft.

Demonstrating that most accodents occurr in the early phase of flight testing would certanly help your case.

 

[Ironflight]

I wonder how hard it would be to catalog the accident statistics for the first 40 hours of flight time for owner built aircraft.

Demonstrating that most accodents occurr in the early phase of flight testing would certanly help your case.

This has been done recently, and some of the results can be seen if you read the new Advisory Circular on the Additional Pilot Program.

The flaw with accident statistics, of course, is that so many mishaps - especially with experimentals - go unreported. In all of my decades of flying these things, I'd say that I hear of at least as many mishaps where gear have been wiped off, wingtips bent, or props bent on nose-overs as I read in the official reports. none of these events are fatals, of course - so if fatalities are all we're cocnerend about then the offical reports are usually good. But if we want a real window into the ways pilots get in trouble and bend airplanes, the official database isn't goign to cut it. It's a dilemma no one has yet been able to solve.

 

[rzbill]

I agree that the 40 hr probably does not apply to the assembly projects being built today. My FSDO thought the same and gave me 25 hrs.

Two points of opinion.
One. I'm not sure a newby test pilot can do a full test program in less than 25 hrs. I had trouble doing all of it due to flight conditions combined with terrain causing a lot of scatter in the data.

Two. I think some craft still need 40 hrs to keep from killing a passenger. Hopefully the builder kills himself before he has a chance to have a passenger on board. Case in point is a Flea I saw at Abeline. It's a 40 hr job if it ever flies.

How do we differentiate?

***EDIT*** Per Darwins first post, I need to be more positive....probably right.....

I think Paul's idea of task oriented phase work is maybe the best way to head. The FAA AC 90-89 could be a place to start with the details of the test program itself.

 

[SHIPCHIEF]

I'm in the unique position of starting my 40 hour phase 1 period powered by an auto-conversion engine, and switching to an adapted Lycoming helicopter engine (IVO-360A1A) and CATTO prop after 16 flight hours.
I'm researching how to proceed with the FAA form 8130-6 for the engine & prop change, and consider proposing a 5 hour Phase 1 test period for this alteration to be flown off within the remaining 24 hours, in the same flight test area listed in the Operational Limitations.