Legal Eagle XL Test Flight Report

[Bob Wood]

After many taxi tests and hops I test flew my XL for my first solid hour this month and several times since.  My 2000 hours are in my Tripacer and other trikes, with 2 hours in a PA-12 tail dragger years ago. I got used to the low inertia, high drag situation very fast due to my Tripacer. I expected to drop like a stone upon closing throttle and flaring high. Not the case, very similar to my Tripacer just much slower.

Some observations that may help new XL Pilots:

I do know know how it happened but my trim and CG feel tight on. My CG is at 25% of chord. My weight is right at 253, uv blocker/primer only on tops of flying surfaces, no paint. Just a joy to fly. Very light on controls.  My Horoz, stab is set up 2 degrees low of level. I added 1" of headroom via wing support tubes.

My 37 HP Mosler TN 54x22 prop jumps right off (I weigh 185#) WOT at about 3400rpm, static on ground 3100rpm.( 150# thrust on ground)  Seems to run best with 100ll. C/ratio 8:1.  Will try mogas again down the road. Running 2 Mikuni 28mm. Jetted to 150 & 140

I put in the diff throw belcranks from the double eagle and my rudder inputs seem very light to keep the ball in center and coord turns.  I am very aware of rudder input because of my newness to  taildragger flying I had to think about a lot at first. Easy transition.

Biggest problem I had was finding a level attitude when flying at cruise.  I ended up putting a small barrel level on the side seat tube we use to level the plane on the ground. Eliminated my always climbing and showed me what level looks like from the cockpit in the air.

I calibrated my A/S indicator with a hall indicator which was a good idea as I was 12-15 MPH low . I adjusted the static tube pressure and got it zeroed. Moved the little collar back on the tube toward the small drilled holes.

Flew my first crosswind landings last week with no surprises. Seems like 10 knots is about tops to fly these, but I do not know that yet.

My first flight was very exciting and I finally relaxed in the pattern after about 20 min.  My first test flight and had some jitters....

Really a great flying aircraft.

[dz1sfb]

Thanks for the report Bob! Quite encouraging. 

[Jim B]

Bob
As a new plans holder of serial number XL-F-47 I received about 3 weeks ago, I do appreciate your report.  I am concerned with the weight as I want to build a legal ultralight.  You did very good coming in under the 254 number.  What instruments do you have installed?  Did you deviate from the plans?  You stated you have 2 degrees of incidence in your stabilizer, by that do you mean the leading edge is lower than the trailing edge?  
Thanks
Jim

[Bob Wood]

Jim,
Yes 2 degrees negative of level. so leading edge 2 degrees from level.  Stick to the plans...Mine is so close, i have to take out radio & its battery. to make it.

I have several of the belite instruments in it and want to do more.  Oil temp gauge is worthless. I have not flown in really hot weather, but will probably dump it after this summer , hardly have seen 100 degrees so far then flying in the 60's.The old time Hall A/Speed gauge is accurate and simple and light. 

I sort of got a kick of watching the weight. A lightening whole here and there in steel and cast aluminum adds up.

I can still take some weight out of my engine, and I rib stitched my wings, engine safety cable, so I did not skimp on safety...These added up to so little i kept them.

Good luck.

I am thinking of building another one.....really enjoyed it!!
Bob

[Jim B]

Bob
Thanks for the info.  I am thinking of only oil temp, oil press and tach for engine instruments and a hall ASI with an altimeter for flight instruments.  I have a hand held radio to carry on my person as it will not add to the empty weight.  I will take your advise and drill a few lightning holes as I go along to save weight.
Thanks again
Jim

[dz1sfb]

Bob,
Looks like you utilized the spring suspension. Does it need it with big floaty tires? I was thinking to build without and see how much room for additional weight I would have.

[Bob Wood]

Good Plan, I did the same thing and only put them back on because I wanted to try a shorter strut length to improve my alignment of tire to ground.  I was running 8 lbs of pressure it it felt great. I will probably take them off when I think the tracking is where I want it., and cut the sold struts to the correct length and use them.

[Jim B]

Bob
I have reviewed the plans and do not see any mention of the stabilizer angle of incidence.  Is there a note or some additional information that addresses how to mount the stabilizer?
Thanks
Jim

[Bob Wood]

No Does not really say, i hung around this list and read all I could on rigging , and everybody seemed to be trimming down after test flying. You set it up so So you have to add washers to adjust the cables and the incidence.

I took a shot at -2 degrees and got lucky. There are so many other factors that can effect trim, I just got lucky.  I gas welded my fuselage and it is not perfectly aligned when you eyeball it from prop to tail post.....But it sure flies great.

Have you started yet?

Bob

[Jim B]

Bob
Thanks for the reply.  I  am also reading all I can on the list to develop a sense of the LEXL.  I have built my rib jig and ordered my wood to start the wings which I hope to have in a couple of weeks. One of the many reasons I settled on the LE design was the wood wing.  I built a TEAM miniMAX back in 89/90 and really enjoyed the build and flying it.  I built a KOLB MK3 Extra in 03-05 but sold it when I finished my  Sonex in 09 which I still have and fly.  I do like the low and slow flying but was not to crazy about the 2 stroke engines as I had several engine outs.  I am looking forward to flying behind the 2 cylinder VW engine.  I have always wanted to weld up a fuselage, so the LEXL fits the bill on several fronts. It is a legal ultralight, has a 4 stroke powerplant, a good wing design and a 4130 fuselage.

Looking forward to reading more reports on flying the XL.

Thanks
Jim

[Bob Wood]

Jim,
I will keep posting reports, i sent you an e-mail on Sonex etc.  I am going to be doing alot of flights between now and Air Venture and will have lots to say. I took my flight testing very slowly and it went very well. I was more conservative than I needed to be, but that is the way I do airplane stuff!!

Bob Wood