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Re: Conex

PostPosted: Wed Feb 03, 2016 10:46 pm
by ededoad
I put another .8 on it today, tried to check airspeed. I believe the airspeed is reading (5 to 10 mph high) but it was a little to rough for good readings today.

The propeller is a 60X56. I have 6X5 inch wheels and 15X6 tires to keep the prop out of the ground. With 96 lbs of fuel and my 200 lbs The CG is at 64.3 inches or 21% MAC. Battery is behind the seat an 4.3 lb weight under the stabilizer. The only sticker I have is the warning to passengers.

I will pass along performance figures when I get still air and the time to record it.

Regards, Ed

Re: Conex

PostPosted: Wed Feb 03, 2016 11:42 pm
by rizzz
That's great Ed,
Would you be willing to share empty weight of your aircraft as well?
Thanks,

Re: Conex

PostPosted: Wed Feb 03, 2016 11:44 pm
by rizzz
ededoad wrote: The only sticker I have is the warning to passengers.

Something like:
"Warning, this Sonex is equipped with a certified aircraft engine"
:mrgreen:

Re: Conex

PostPosted: Thu Feb 04, 2016 9:57 am
by Sonerai13
ededoad wrote:The propeller is a 60X56. I have 6X5 inch wheels and 15X6 tires to keep the prop out of the ground. With 96 lbs of fuel and my 200 lbs The CG is at 64.3 inches or 21% MAC. Battery is behind the seat an 4.3 lb weight under the stabilizer. The only sticker I have is the warning to passengers.


What is your empty weight, and where did you set the gross weight?

Re: Conex

PostPosted: Thu Feb 04, 2016 4:53 pm
by NWade
rizzz wrote:
ededoad wrote: The only sticker I have is the warning to passengers.

Something like:
"Warning, this Sonex is equipped with a certified aircraft engine"
:mrgreen:


And then we can add another sticker below it:
"WARNING: A certified engine provides no additional protection against mechanical failure, improper maintenance, poor installation, or abuse"

To be clear: I have no beef with the person who did this installation - its experimental aviation and I hope they did careful and considerate work that they can be proud of.

I just don't get people's fascination with putting a LyCon on a Sonex. It simply does not provide any tangible benefits over-and-above the other options out there. If you feel that a certified engine provides some inherent benefit just because its certified, then that's just a statement about your understanding of what "certified" actually means.
(Hint: It basically means that the manufacturer submitted a ton of paperwork. In terms of engine reliability they just have to prove that it'll run for ~35 hours and not require major adjustments. The regs specify 150 hours of testing, but your'e allowed to use different engines for each run, and the longest test is only 35 hours long.)

--Noel

Re: Conex

PostPosted: Fri Feb 05, 2016 10:38 am
by ededoad
Empty weight is 751 Lb. gross will be determined by flight testing. I told the FAA inspector between 1230 and 1250.
After 1 hour I will probably go for the 1250.

It is a little heavier than I wanted but I painted it inside and out and put too much paint on the out. If I did it again I would use wrap film .

Regards, Ed

Re: Conex

PostPosted: Fri Feb 05, 2016 2:01 pm
by Sonerai13
ededoad wrote:Empty weight is 751 Lb. gross will be determined by flight testing. I told the FAA inspector between 1230 and 1250.
After 1 hour I will probably go for the 1250.

It is a little heavier than I wanted but I painted it inside and out and put too much paint on the out. If I did it again I would use wrap film .


Thanks for posting this info. This serves to illustrate that, while anything can be done, there is no free lunch. Everything has a cost. The cost in this installation is weight. The airplane ends up approximately 100 lbs heavier than a Sonex built with a factory-supported engine installation. This means that, in order to stay within the aerobatic gross weight, and thus guarantee the 150% safety margin at 6 G's, you can only have 10 gallons of fuel and a 139 lb pilot (and nothing else in the airplane). The same holds true of max gross. A 100 lb heavier airplane, and a 100 lb heavier gross weight, means that, at gross, you no longer have the 150% safety margin at the utility category limit of 4.4 G's.

This is not to knock the decision to go with this engine and this configuration. As has been mentioned previously, that's what experimental aviation is all about. However, it is important to know that every decision has consequences, and these should be given serious consideration as building decisions are being made.

Re: Conex

PostPosted: Fri Feb 05, 2016 4:14 pm
by fastj22
Sounds like the Conex is right there with the Corvair Cleanexs. My Jab Waiex is a bit chubby too at 706lbs because I like toys.

Re: Conex

PostPosted: Fri Feb 05, 2016 6:11 pm
by Waiex 49
Pretty much any larger engine Sonex is going to weigh more than a VW powered Sonex. No rocket science there.

The O-200 is a pretty good engine and has been out there for a long time. I don't have all the statistics, but I would bet that if you looked up the numbers the service and reliability record of the O-200 looks pretty good when compared to VW conversions. Yes, the VW is lighter and cheaper but not everyone wants to fly behind a VW conversion.

My Viking Waiex will weigh in more than it did when it had an AeroVee engine. It will weigh somewhere around the same as the Corvair powered Sonex aircraft. My engine is heavier and I have built a larger instrument panel that I have filled with avionics. Yes, it is going to be heavier than a VW powered Sonex. I'm not worried about the aerobatic weight limitations because I hate aerobatics. I want an airplane that goes places, not one that goes upside down. Just my personal preference.

Prop clearance might be an issue on some large engine Sonex aircraft, but in my case the Viking runs a 62" three-blade Warp Drive ground adjustable propeller.

Modifying aircraft isn't for everyone and I don't advocate just anyone doing this. My greatest wish would be for Sonex to build a slightly larger version of the Sonex aircraft for those of us who want more powerful engines, larger cabins, more fuel capacity, etc, I think this could be done and still keep it within the 1,320 lbs sport pilot limitations.

Just my 2 cents worth.

Don Bowen
Viking Waiex N49YX

Re: Conex

PostPosted: Sat Feb 06, 2016 3:34 am
by NWade
fastj22 wrote:Sounds like the Conex is right there with the Corvair Cleanexs


Except the Corvairs are still a bit lighter, AND put out more horsepower than an O-200.

Waiex 49 wrote:Pretty much any larger engine Sonex is going to weigh more than a VW powered Sonex. No rocket science there.


OK, but larger does not mean better. An O-200 doesn't put out as much power as a Corvair, Jab, or Camit. Yet it weighs more than any of those options. There simply is no advantage to carrying extra dead weight.

--Noel