by taliotta » Thu Jul 20, 2017 10:28 am
It has taken me quite some time to get signed up to reply to your post. I am the owner of N390SG and would love to tell you what happed. This Sonex is one of the best equipped Sonex out there. I am going to list the equipment because that is part of the story. It has the Dynon D180, AvMap, Dynon AP 74 Auto pilot, Becker radio, and the Micro air Transponder. The Revmaster has a Turbo with EFI and controlled by the SDS system (Simple Digital System). The SDS system is its Achilles Heel. Sure it will fly to 10,000 without loosing power. It never needs mixture control, you just start the engine wait until you have 110 degrees on the oil temp so that you don't get oil blow-by from the Turbo, and go flying. No mags and nothing else to check accept the normal amps, volts, fuel pressure, oil pressure and so on. So it is only a visual scan of the instruments. I live in Central MO and took a neighbor for a flight to just bore holes in the sky. We climbed to 2500 ft and set the Auto pilot and I used the Bearing dial to change course. We did a square pattern and on the third leg I dialed up an Airport at the Lake of the Ozarks and headed to the lake. About mid point of the lake my radio and transponder just shut down, followed with the GPS a couple of seconds later. The Dynon became very static, and I notice that my volt meter and amp meter were pegged at the bottom. I turned off the Auto Pilot and entered a climb and headed towards the hwy since there is not a suitable place to land at the lake and all the terrain is highly tree'd. I lost the Dynon at 2,900ft and a couple of seconds later the Engine stopped with the prop horizontal. I put the nose down and flipped the AV master on and the Dynon came on for a couple of seconds so that I was able set my best glide at 70. I tried to restart but nothing at all. I had my passenger turn the fuel off as I shut down all electrical switches and concentrated on landing. As I turned at the Highway, I noticed a long grass field off to the right in a perfect distance to glide to so I chose that instead of trying to land with the 4th of July traffic. I flipped the AV Master just over the trees to see 67 mph indicated, put in full flaps and held it off the field until I bleed of my speed and touched down at 47 mph. This is a conventional airplane so I held the stick full back to maintain control on the tail wheel but I had floated a bit longer than I wanted and a barbed wire fence loomed about 50 ft in front of me but I was able to steer the plane between the T posts that hit each wing, and 10 feet after the fence was a drainage ditch about 2 ft wide and 10 inches which caused a partial collapse of the gear. I can't say enough good stuff about the strength of the Sonex, the wings held up, and the gear kept me from going Turtle. We weren't even sore the next day, because it was actually a very smooth landing. Thank you Sonex. Now about the Turbo. I didn't build the plane, and I frankly don't know where the builder got the Turbo from, but it worked great and I know that Joe at Revmaster is working on a Turbo unit as I write this. But the SDS System, while it is a fine unit, it is a weak link in the system. Had I had a carb with mags my engine wouldn't have quit and I wouldn't have a totaled airplane. I will never own or fly any aircraft that depends 100% on electrical power to fly. I have been a pilot for 29 yrs and this is my first off airport landing due to engine failure. I hope I have answered all your questions, but if there is anything else I can tell you, let me know, since I will a monitor this website a couple times a week. The Sonex and the Revmaster are both great products and that turbo was a bonus but stay away from the SDS System.