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It is not recommended in the POH but has anyone tried a snap roll in their Onex?
If yes, what entry speed?

For anyone interested my entry speeds are for loops & aileron rolls 130 kias, barrel rolls 140 kias, split S 80 kias
I am only seeing a roll rate of 100 degrees per second.
Cheers Peter

Snap rolls are really hard on airframes. The load is not symmetrical, and tail loads can really get quite high. Also, although you probably won't exceed +6Gs, the G onset rate will be very quick, which will cause more damage than the same G if loaded statically, as tested.

Please don't do snaps or tail slides intentionally in the Sonex/Waiex/Onex. It is really hard on the airframe and it is not designed for the loads snap maneuvers introduce on the aft fuselage.

It's an interesting discussion. The Sonex series are built like a proverbial tank compared to some vintage aircraft in which we do all manner of manoeuvres that weren't 'designed for' as such. I remember a lot of debate about the wisdom of doing snap rolls (which we call flick rolls) in the Stampe, where the 350lb Gypsy engine was mounted to tiny, oil-soaked wooden longerons. But snap them we did, and the engines never fell-off. However I'm happiest as a follower rather than a leader when it comes to in-flight proving of aircraft structural suitability.

A snap roll is just a spin....that is started and hopefully ended on a horizontal trajectory. In order to accomplish this you have to be well above 1g stall speed. If you want to work up to it, start slow perhaps at 80mph. If there is not enough energy to complete the roll the. You will end up in a spin. Recover and try another 5 mph. When you find the slowest speed at which it will make a revolution then you have found your entry speed. The faster you go the much higher the loads you are imparting to the airframe and cranckshaft. Keep in mind that the factory advises against...one final thing, Your pull and rudder input need to be rapid, but should be a smooth pull not a jerk.

Gordon

Along the same lines of snaps not recommended, I did anyway in my RV6 at the top of a loop. The noise of oil-canning mega-horning out from the back of the fuselage was screaming that this is not a good idea. No wrinkles or any other sign of abuse detected, but the airplane spoke to me. Sixteen years later, still flying acro in my -6, but no snaps.

I'm sure your Onex will be screaming at you too if you try it.

Rick Caldwell
Xenos 0057

Thanks all, I posed the same question to Sonex, and received a prompt and thorough reply - love the customer service - which essentially said no the Onex has not been snap/flick roll tested by the factory, that it is a strong airframe so is probably possible, that the low entry speed needed (because of the low stall speed) would probably make the manoeuvre difficult to perform.
I'll keep it on the backburner for now, practise more spinning and think about it later.
Thanks Peter
Onex120