Phase I flight test completed 9/26/2012.  Phase II now active, but weather has prevented much flight.  The weather around here (Pacific NW rain forest) should clear up around May 2013.  I plan to do some real cross country flying at that time.

All problems fixed in Phase I except lack of yaw stability.  That seems to be inherent in the design.  There is no vertical stabilizer because of the full flying rudder and no portion of the fuselage side is parallel to the line of flight.  It seems the plane is just as happy flying +/- 11 degrees in yaw from straight since it presents the same cross section to the air flow in any of these positions.  This is more of an annoyance than a problem.  The plane flies fine - it just doesn't care whether the nose is going straight or somewhat left or right of straight.  The only time this is a problem is on landing when it is nice to have the plane pointing straight down the runway while flying straight down the runway too.

Air speeds for cruise can easily exceed 120 KIAS with full throttle on the Jabiru 3300 but this is not very comfortable unless the air is very stable.  Any turbulence is very uncomfortable at this kind of speed.  Normal cruise is more like 110 KIAS with engine set around 2700 RPM.  I found takeoff with half flaps to work best.  No flap takeoff works fine while using more ground roll but full flaps seems to lift off before there is good control of pitch and yaw.  Landings work best with full flaps.  No flap landings work fine but touch down faster and use more runway.  Final approach speeds around 60 KIAS or a little less work well.

The instrument panel has worked consistently during phase I.  Dual Dynons with HS-34 gives excellent flight and engine condition indications along with easy navigation with combination of Dynon HSI display and choice of either VOR from Garmin SL-30 or Garmin Aera-500 GPS driving course and deviation information on HSI.  Garmin transponder makes the plane suitable for VFR operation in any US airspace - at least until 2020(?) when ADS-B will be required.  Radio frequencies can generally be set into the Nav/Com radio from the GPS just by touching the line containing the frequency in the GPS database.

This should be a fine cross country travel plane with just the pilot and baggage or two full sized Americans and little or no baggage.  I haven't really checked fuel consumption yet but I expect around 5 GPH at 110 KIAS to work.  I didn't do a formal calibration of the airspeed indications, but the GPS seems to indicate the same ground speed as the airspeed indication when there is no wind.

I built and installed a Lift Reserve Indicator.  It seems to work fine, but stalls don't include any real break.  The plane goes into a steep sinking condition around 45 KIAS or a bit less but the nose doesn't drop.  The LRI does a fine job of showing safe airspeeds - especially in low speed turns as are common in the traffic pattern.

I don't know if I will keep the plane or sell it if the FAA approves the increased plane choices for those of us flying without a third class medical certificate.  If they go as far as the Australians with a gross weight limit rather than engine horsepower limit as proposed by EAA/AOPA then I might trade the Zodiac on a C-182.  That way I can actually take my wife and baggage cross country all at the same time.

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Comment by Danal Estes on February 4, 2013 at 3:42pm

I have talked to FAA DAR's extensively about a second person during Phase I.  I tried to pull the "Required for logging data" card, and many other scenarios, including an instructor for Dual Received and/or time in type or similar.  All "required" in some way.  All No Go. 

"Required" means "Required by FARs to conduct that specific flight operation" and nothing else.  I have been unable to come up with a flight operation that requires two pilots and is also legal within the 'normal' Operating Limitations Phase 1 testing of our aircraft category/class/type.

No second seaters in Phase I.  Period.  Anything else is wishful thinking.

Unless you are willing to look at a fine and/or suspension and/or revocation if caught.

Comment by Paul Mulwitz on December 19, 2012 at 3:40pm

Louis & Joe,  I tend to agree with Joe that only required crew members are allowed to fly in a plane in phase I flight test.  This may be open to interpretation, but those interpretations I have heard clearly favor the notion that in a plane like a Zodiac only one person is allowed.

That said, it makes a lot of sense for the builder of an experimental plane to do some of the flight testing.  This should include a checkout in the type or the actual plane before attempting solo flight.  I have seen instructors give checkout assistance in home built planes before they completed phase I.  This makes a lot of sense even if it may be against the rules.

The one thing I would recommend against is a rusty pilot with no time in type attempting to fly a new home built plane.  This is a formula for disaster.  It makes more sense to get a checkout in the experimental plane first whether the rules support this idea or not.  Ideally the checkout will be accomplished in a plane already completely done with flight test, but this is not always possible.

Comment by Louis W. Ott on December 19, 2012 at 2:29pm

Hi Joe,

I think you are correct. The PIC of an experimental during phase 1 tests can choose to have a crewmember to assist him in doing whatever tasks he deems necessary. This could be recording instrument data, watching for traffic, or something else. It is true that most experimental flight tests probably don't require another crewmember, but it isn't prohibited.

Comment by Joe Zinkel on December 19, 2012 at 1:54pm

Hi Louis,

Sorry to jump in here, if I understand you correctly, you are planning on flying with a CFI during phase one? according to my Tech counsler who works at EAA in Oshkosh this is not legal. A crew member is allowed if there is a situation that requires a co-pilot. Most experimentals rarely need this.


Comment by Louis W. Ott on December 18, 2012 at 12:43pm

Hi Paul,

Thanks for your offer and suggestion about flying in low winds at the beginning. I should be able to do that since the big winds don't begin until April or so. Runway 31 (recently changed from 30) at KDLS does align with the prevailing wind so that is a help.

I think I have something worked out for the first flights. I'll have the local instructor fly it the first time. Since I haven't flown anything in about 15 years, I need a BFR and TD refresh. He suggested that I have him go with me in my airplane and I can get familiarization in the airplane and get me legal at the same time. Actually, he would be PIC until I was signed off. The DAR said this would all be within the phase 1 rules. The PIC can have whoever he wants as a crew member during phase 1.

Comment by Paul Mulwitz on December 18, 2012 at 6:07am

Louis,  Send me an email when you get closer to flying your Zodiac.  If you need some stick time I'm sure we can work something out.

On your first flight - I would recommend you wait for low winds before flying your plane.  A few thousand feet of ceiling would be a good idea too.  High winds are a real nightmare in a Zodiac because of the low wing loading.  Any instability will have you bouncing around the cockpit.  This is not the kind of problem you want on your first flight.

The Dalles is a nice airport for your testing.  It has runways going every which way so you don't have to deal with heavy cross winds.

Good luck,


Comment by Louis W. Ott on December 17, 2012 at 1:28pm

Hi Paul,

I've completed my 601 XL B TD (Corvair) and waiting for the DAR to come and have a look. I'm located not too far from you up river at The Dalles airport. I appreciate your reporting on your phase 1 testing and especially the lack of yaw stability and your attempted fix. I will be looking for similar characteristics when I fly mine. The weather is poor right now, but when it improves in the spring we have near continual high winds so when I do the first flights it'll be a toss up whether during low winds and ceilings or clear skies and high wind. It's always something...

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