SonexBuilders.net

Hey guys! Hoping you to get some info from those who have had their sonex for a while now and those near completion. I was curious if you guys can let me know in terms of weight and balance the most weight I can add in terms of instrumentation if I were to go with the Aerovee Turbo engine.

I know this is a topic that has been discussed in the past but I am thinking of a sonex B with IFR capabilities. Not because I willbe flying IFR in IMC especially if there is crazy weather. I understand it's a small platform and whatnot but living in California, when the coast has low lying clouds because of the Marine layer that likes to stick around in the summer, I would still like to visit those airports. Just to let you guys know, I am IFR ratedso capabilities wise I am not worried. I won't have an autopilot as I have never used one so I am not worried about that weight.

I knowmi have to adhere to 91.205-.213 i think it is. I understand that the alternator needs to be big enough and all that.

This is just a dream of course I am not ready to start building yet but hopefully will in like 2-3 years. For now I'm trying to decide between the sonex B and vans RV 7. They both have their pros and cons of course.

Thanks for your time and sorry for beating the dead horse once again with this topic.

Of course you can pick any weight you like if you can justify it and stay LSA - but performance - especially if you need to meet departure climb rates for IFR - you want to keep it light.

AeroVee Turbo allows a factory approved gross weight of 1,200lb Up from 1,100 of the non-turbo.

That's all I know.

My Waiex B has the Aerovee Turbo up front. I have all Dynon avionics including a Dynon 10 inch HDX, AutoPilot, A/P Expert panel, Baro/Alt/Hdg/Trk Knob Panel, Intercom, Comm Radio, Xponder, ADSB in and out. I run an IPad Mini on the right side of the panel. I don't think all of this stuff weighs 15 pounds, I could be wrong, but not by much.

The Scottsdale FSDO sent out 2 inspectors for my airworthiness inspection prior to the first flight. They took about 2 hours going over the plane. I showed him how all of the avionics worked and he said, "I'm going to sign this plane off for IFR flight". It didn't occur to me to ask him for that, he just announced he would. So......my Waiex is ready for a marine layer. Go Figure!

pappas wrote:My Waiex B has the Aerovee Turbo up front. I have all Dynon avionics including a Dynon 10 inch HDX, AutoPilot, A/P Expert panel, Baro/Alt/Hdg/Trk Knob Panel, Intercom, Comm Radio, Xponder, ADSB in and out.

......

So......my Waiex is ready for a marine layer. Go Figure!

That was a nice surprise!!

What do you have for ADSB in and out?
It’s all in the Xponder? Which one?
Or is it through any other device?

Carlos

pappas wrote:My Waiex B has the Aerovee Turbo up front. I have all Dynon avionics including a Dynon 10 inch HDX, AutoPilot, A/P Expert panel, Baro/Alt/Hdg/Trk Knob Panel, Intercom, Comm Radio, Xponder, ADSB in and out. I run an IPad Mini on the right side of the panel. I don't think all of this stuff weighs 15 pounds, I could be wrong, but not by much.

The Scottsdale FSDO sent out 2 inspectors for my airworthiness inspection prior to the first flight. They took about 2 hours going over the plane. I showed him how all of the avionics worked and he said, "I'm going to sign this plane off for IFR flight". It didn't occur to me to ask him for that, he just announced he would. So......my Waiex is ready for a marine layer. Go Figure!

Lou, I believe that, to this day, the Dynon GPS is not certified for IFR flight. Even Dynon's own literature says that an external IFR approved GPS is required to be added to their system in order to meet the FAR requirements for IFR flight. So with that being said, it appears to me that the FAA inspector was in error in certifying your Waiex for IFR flight. Perhaps I'm missing something.........and it wouldn't be the first time for that to occur.

Art,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,Jabiru 3300 #261

ADSB in and out is all Dynon. SV-ADSB-472 Dual Band Traffic and Weather Receiver, and the Class 1 SV-XPNDR-261.

There have been many, many, discussions over the years about IFR "approval" in experimentals and lots of opinions. The last time I looked into it, I remember that the "powers that be", (FAA), made clear reference to the fact that the PIC was responsible for determining that the equipment in the experimental aircraft was "suitable" or "capable" for the intended IFR mission. I don't have the equipment to shoot a precision approach. But I do have the equipment to fly through a marine layer or a GPS approach. There seems to be a difference between Certified aircraft and ours in this area. Here is another interesting discussion:

https://airplaneacademy.com/can-you-fly ... imitations.

However, realistically for me, I can almost never find any IMC here in Phoenix or the places I usually go like Vegas. Most of my flying is desert. Even when I go to San Diego in the summer the marine layer has burned off by the time I get there around noon. But, it is a pretty nice thing that we have so many choices in experimental aviation.

pappas wrote:ADSB in and out is all Dynon. SV-ADSB-472 Dual Band Traffic and Weather Receiver, and the Class 1 SV-XPNDR-261.

There have been many, many, discussions over the years about IFR "approval" in experimentals and lots of opinions. The last time I looked into it, I remember that the "powers that be", (FAA), made clear reference to the fact that the PIC was responsible for determining that the equipment in the experimental aircraft was "suitable" or "capable" for the intended IFR mission. I don't have the equipment to shoot a precision approach. But I do have the equipment to fly through a marine layer or a GPS approach. There seems to be a difference between Certified aircraft and ours in this area. Here is another interesting discussion:

https://airplaneacademy.com/can-you-fly ... imitations.

However, realistically for me, I can almost never find any IMC here in Phoenix or the places I usually go like Vegas. Most of my flying is desert. Even when I go to San Diego in the summer the marine layer has burned off by the time I get there around noon. But, it is a pretty nice thing that we have so many choices in experimental aviation.

All good points, Lou. However I think it would be difficult to defend the Dynon's GPS suitability for IFR flight when even Dynon says it doesn't meet the requirements for IFR flight and, in fact, in their manual they recommend a few IFR certified GPSs that will interface well with their equipment if the user wishes to go the IFR route. Regardless, I still find it interesting that an FAA inspector would approve your Waiex for something that you hadn't even asked for. When I had my Sonex inspected in 2005 by an EAA volunteer inspector (remember those?), I got only what I had asked for, nothing more.

Art

Avionics choices will be one choice of many in terms of the final empty weight of your airplane, and as Lou pointed out, in todays world of modern avionics and integrated EFIS systems, the weight in avionics really doesn't need to be all that much and still have a fully functional avionics suite. The Dynon, Garmin, and MGL systems are all so integrated that you can make things pretty easy, not tie up too much panel space (or add weight) and yet still have a lot of capability.

Remember, when you build an airplane you will also be deciding on exterior paint options, interior upholstery, other misc. options (bigger tires, heated seats, exterior lights, etc) and all of those choices will have an impact on how much your airplane will weigh. I would be willing to bet a nice paint job will weigh more than a basic avionics package at this point!

When considering any IFR flying in a Sonex, it's important to understand a few things. As you've said this conversation has happened before on these forums and each builder will have their own opinion. In the end, it will be your decision on what you feel comfortable with but you will face some of the following considerations:

- The airplane really isn't designed for IFR flying. The neutral stability designed into the airframe does not make it difficult to fly, but it would be something of a handful for any IFR flying for any long duration. It's a sport plane meant to have light control forces so it's fun to fly.

- The alternator on the AeroVee is rated at 20 amps so you would need to be a little cautious on how much power you draw. The avionics shouldn't be too bad but when you add lights and other accessories, that power draw can add up.

- In most cases, a nicely equipped Sonex will end up weighing around 700 lbs which gives you a useful load of around 500 lbs. If you want to add IFR equipment (depending on what you feel is necessary) such as a navigation radio, exterior antennas, a heated pitot tube, etc. that will cut into the useful load a little. Nothing wrong with that just a consideration.

Regardless, it's your airplane and your decision. Best of luck on your adventure!

Having owned a Sonex AeroVee Turbo and a RV-9A, and IMC time in a 7A, my thoughts are:

1) Review your mission closely. If you fly IMC on a regular basis, I would skip both the Sonex & RV-7 for a RV9. The airfoil is superior to flying in IMC conditions. You will have to work the RV7 if you have to fly to minimums, even with A/P coupled approaches. It is a high speed plane with very light/sensitive controls. There is a huge price difference between the two, you are comparing a Chevy Cobalt to a Corvette. My Sonex leaked around the canopy, another issue in IMC, Fog, Rain, etc.

2) Speed and Range: Another big consideration. I never found the Sonex to perform at the factory speeds unless it was built simple and light. Load it up with extra fuel, avionics, A/P, etc and performance suffers. Very important as a 500ft+ min climb rate is required for IMC. A heavy Sonex with two adults can struggle with that on a warm high-DA day. The Vans numbers are spot on if you build a straight plane. I always filed for 145kt (166 mph) with a fixed pitch 160hp Lycoming at 65% power. And my plane was heavy compared to most. I love the performance/power/reliability of a big Lycoming, thus why my new build will have a 320 or IO-340 stuffed under the hood.

155-160kt if you fly the RV7. Range is short on the Sonex for IFR as well with the tank size. 36gal on the RV (assuming you don't extend ribs to 50gal), will give you 4 hours (7.5gph) endurance with 1 hour reserve (664 miles). If you add pMags / CS prop and a Titan IO-340 on the same airframe you get down to 4.5gph at 145kts extending your range to 1,000+nm.

3) As Mike stated, the Sonex is not meant for heavy IMC flying and I, personally, would never trust an AeroVee in IMC. If you wanted the Sonex platform and IFR, my recommendation would be a 912is Rotax over an AeroVee.

4) An IFR navigator (530/625) with required backup instruments will draw a lot of power and required to fly IFR, as already covered the Dynon does not meet FAR requirements. My 9A was nicely equipped and on a LPV approach with A/P and auto trim engaged was loading over 45amps (Dual SkyView Touch, 530W / 430W / GTR200 / GMA245 / Heated Pitot, etc.). It was easy to land at night in IMC after a 6 hour day of exhaustive flying. Something I'd never do in a 7 or Sonex.

Best of luck to you and your decision! If you haven't joined VAF (Vans Air Force), do so and check out their threads on flying IMC, Classifieds, etc. Great kits come up at an excellent price. And nothing beats flying behind a big Lycoming during night / IFR flying.

:)

The OP stated he may want to pop thru the Marine layer occasionally to go places. Back before color TV, I had a Grumman Yankee (late 80's) with its one NAV radio and a Gyro turn coordinator. Against all the 'opinions', my partner and I used it for our IFR training and occasionally popped thru the 1000 ft Florida summer cloud deck to get VFR on top to go somewhere. It was pretty common to file tower-tower to do this. We would be on instruments for all of 5 minutes. With my little MGL Xtreme and my iPhone running Foreflight as a back-up, I feel INFINITELY safer doing that these days, even behind an AeroVee. Come to think of it, the iPhone with the Foreflight synthetic vision is better and more reliable than ANYTHING out there under 5 figures.

Looking at the actual current load of my Onex with MGL Xtreme, COM, Sandia transponder, ADS-B, NAV lights, and iPhone charging, the total load is around 5 Amps. That secondary ignition will draw 5 amps. Lets double that and say its 20 total. Oh No! the alternator might not keep up. But wait, our plan is to pop thru the layer and go back VFR. Unplug the iPad, turn the NAV lights off, and carry on. And if the volts look a little low and you have a ways to go, turn off the secondary ignition for a bit and let the battery recharge.

So what do you really need to pop thru that marine layer a few times a year? Everyone has to do what they are comfortable with. I don't have one but I just love seeing homebuilts with Space Shuttle instrument panels in them. Especially when its not my wallet! And not to beat a dead horse, but look at accidents. These just don't happen often.