Flight Test Report - N773PM

Zodiac XL - Jabiru 3300

By Paul Mulwitz -- June 2, 2012

As phase I flight test nears its end I wanted to record some of the things learned about this airplane. The information presented here is not very official, but it might help me or some new pilot have an easy time flying the plane in the future.

Basic flight performance of this Zodiac XL is relatively tame. It has plenty of power and cruises easily over 110 KIAS. With a heavy throttle it will exceed 120. It has very little or no stability - especially in the yaw domain. There is electric roll and pitch trim but this does a poor job of making it a stable flying airplane. The pilot must pay attention all the time to keep it flying straight and level.

Takeoff is normal. With no flaps the ground roll is relatively short and performance is OK. I prefer using 1/2 flaps until clear of any obstacles. This produces a quicker departure from the ground. Full flaps on takeoff is a poor choice. It lifts off before there is good response to the flight controls. Flap setting is judged by the relative position of the flaps and ailerons. Initial climb at 70 KIAS works well. At 500 feet AGL I start to think about turning crosswind or exiting the pattern and reducing power.

Initial cruise at 2500 RPM works well and gives around 100 KIAS. Maneuvering speed, Va, is 90 KIAS.

Stalls are uneventful. The only thing I have been able to produce is a deep mush.

My preferred setup for the Dynon based panel is to display HSI on the pilot's EFIS along with the flight instruments. RPM is displayed on this display from the EMS. Right seat display varies with the desires of the occupant from completely engine information to a full instrument panel with reduced engine information. HSI navigation data source can be either the GPS or VOR. Selection of the source and setting of various bugs and track information is done with the HS-34 knobs just below the pilot's display. The knobs also act as push button switches to sync the bugs.

Like all low wing planes, fuel must be drawn from only one tank at a time. My common practice is to use 1/2 hour fuel from one tank and then to switch to the other one. This keeps the fuel load somewhat balanced.

When approaching an airport for landing I like to reduce speed to 70 KIAS before reaching the traffic pattern. 2000 RPM is a good power setting for level flight at 70. I continue downwind at 70 and reduce power to idle when opposite the numbers. A glide is set up with speed at 60 KIAS. This is a good speed for the remainder of the approach. While on base leg I judge the approach height and apply full flaps if there is enough altitude. Landings can be made with any flap setting but full flaps give a nicer touchdown speed and attitude.

One strange characteristic of the Jabiru engine is it will not start while windmilling. If it stops firing in flight the only way to get it going again is by engaging the starter motor. Similarly, it is claimed it will not fire from moving the propeller by hand on the ground.

Carb heat is available but I have never used it in flight. The relatively warm position of the carburetor in the engine compartment suggests it is really not needed. I check that it is working when running up the engine before flight along with a quick magneto check. All three checks show only a minimal reduction in RPM from the 1800 test power setting. Magneto checks at idle RPM work better.