Aerobatics with Sonerai II LS - is it possible

[dred]

Hello All of you, Sonerai pilots!
Can anybody tell me what kind of aerobatic capability the Sonerai II LS has?

 

[splischke]

As you know, you shouldn't do any serious high G or negative G aerobatics in a Sonerai. My flight manual lists chandelles, lazy eights, steep turns, spins, loops, aileron rolls, barrel rolls and stalls as allowed maneuvers. I have only performed stalls and steep turns myself. Remember, speed builds quickly in a dive.

-Scott

 

[dred]

Thank you for sharing your experience! You said high G's are not allowed. Why then the plane is rated +/- 6 at solo? I understand that the engine doesn't have inverted flight fuel and oil systems, but this positive limit +6g, allows a lot of adrenaline, I think! Are this structural G limits real for the plane?

 

[Schmleff]

No snapping maneuvers are allowed. That is the greatest limitation.

 

[dred]

Excuse me, but what do you mean by snapping maneuvres? As splischke said above, loops, rolls, steep turns etc. are alowed, aren't they? Best Regards. K.

 

[elkosonerai]

I believe he is refering to maneuvers like snap rolls and other violent maneuvers.

 

[Schmleff]

yes, no snap rolls allowed

 

[DanMcC]

Re: Aerobatics with Sonerai II L/ entry speeds

What are the recomended entry speeds for acro with the Sonerai, and what sort of G should you initialy pull for say a loop?

 

[Schmleff]

I would have to get my flight manual to be sure, but most of the entry speeds are 140mph.

 

[skyFlyer]

My manual says very clearly that all manuvers are 120mph, which means a top speed for these are at 120mph. A manuver is anything except a straight and level flight. Also noting that for Aerobatics are a maximum entry speed of 140MPH which is 122 Knots. Mine has the S mods done so it is rated at + - 9 G's but cant be done at full gross weight. Acros to be done ONLY if UNDER the acro total all up weight of 750 pounds but if under a set of speed entry speed the total weight can be as high as 925 pounds per my operating limitations in the manual. Sonerai I is ONLY at 750 pounds and II at 750 pounds at certain calculated airspeeds. From what Ive been told this could be tricky and get away from you quickly as the nose drops, this inherently picks up speed at a very rapid rate thus the G factor could get rather high quickly and could find yourself in the red unexpectedly.

John
59RR
Sonerai IIL

 

[dred]

This is very interesting, that you are saying, John (skyFlyer)...Could you explain me please, what does "S mods" to be done on the plane mean?
Best Regards
Konstantin

 

[skyFlyer]

Please see "Spar Mod Info Needed" post to see pics of this already done by others but is described as:
"S" mods refer to the spar modifications set out by Monnett Experimental Aircraft, Inc. Service Buletin number 002 Dated on October 20th, 1983.
Its a mandatory Sonerai II Flight Envelope Restriction. It effects the Sonerai II, IIL, and the IILT models. This Modification is explained as a wing mod that can be done to stiffen the spars in the wings to prevent earlier known failures due to Higher than published limitations being performed due to pilots pushing thier aircraft envelope further than what is allowed set forth by the manual. This "S Mod" will strengthen the wings allowing an increaded strength which in turn, increases safety factor and higher G's from +-6 to +-9 G's. If new plans are ordered, the mods to the wings or strengthening is included as standard in the new plans I believe. If you have an older plane with a wing that does not have the "S Mod" done to them, you can get the plans which include plan sheets 13, 14, 15, and 16. It also suggests that this mod be done to a Sonerai I would significantly strengthen the wing and should be considered.
This Mod is detailed as opening the bottom, inboard skin of each panel and installing rib stiffeners as described in the plan sheets and reattaching each inboard skin. This Mod has been done to my wings and also to most but there are several out there which have not been Modified as the owners probably dont do areobatics, or feel it takes too much time or costs too much to do for thier specific situation.
I hope this Info help and I can NOT be held responsible for any mistakes which may have been conveyed wronfully. Do your own research and find out the facts by calling Monnett yourself as he is quallified to give you the facts but this explanation, in my own opinion, is correct and probably will be corrected by toher if this is so.

John
59RR
Sonerai IIL

 

[DanMcC]

Re: Aerobatics with Sonerai / entry speeds

Thanks for the info, we hope to buy a Sonerai this spring, primarily for dual instruction for my son to get his licence and secondarily sportsman type acro. The Sonerai seems to be tailor made for that. What sort of roll rate can a person exspect?

 

[Schmleff]

The wing is only rated for 6 g's even with the mod. Don't go out and try 9.

Very important note fellas.

 

[UpSideDownFlyboy]

Ok, I'm gonna put in my two cents worth here. I have a Sonerai II Original with the A wing and a modified spar. I have seen it mentioned a couple of times now, that with the spar mod completed the G-Load is increased to + or - 9 G's. WARNING! All information that I have and that I have seen states that the spar mod increased the load factor by 1 G. The Sonerai was designed to + or - 9 G's ULTIMATE which gives it flying rating of + or -6 G's. According to my information if the spar mod is not completed then the acro is forbidden and load factors reduced to + or - 4.4 G's. Once completed, the load factor is raised only to the posted load factor of + or - 6 G's and limited acro is approved. I am by no means an expert on Sonerai's, but this bird is my third Sonerai and I would hate to see anyone hurt (DEAD) by misinformation. I have approximately 20 hours of acro instruction, many hours of acro practice, and love to turn the world upside down. I see roll rates between 180 and 200 degrees per second and perform aileron rolls, barrel rolls, slow rolls, loops, hammerheads, split s, immelmans.........with the exception of loops, I have found entry speeds of 100-120 MPH more than enough, and 130 MPH with a 3.5 G pull sufficient for loops. Watch your airspeed very closely! A Sonerai will build speed incrediby fast with the nose down, unlike better aerobats such as the Pitts or Decathalon. If you are serious about acro in a Sonerai, then PLEASE get instruction from an experienced acro pilot before trying it on your own. There are a lot of pitfalls (falling out of the top of a loop for instance) that can send your airspeed right through the red before you realize it!

Do with my thoughts what you will and here's a grain of salt to go with it! Hope I didn't step on anyones toes here, but I feel Safe Flying Benefits us ALL! Especially the pilot flying!

Scott

 

[DanMcC]

Hello Scott,
Thanks for the feedback, I have a Midget Mustang right now and do mostly positive G acro with it as I don't have inverted oil or fuel. I suspected the Sonerai would get quick going down hill I know the M-1 sure does. I have only done acro in my M-1, a Pitts S2 [dual] and a 150 Aerobat. How easy is it to keep the Sonerai inside the box? My Mustang is almost impossible, at least at my skill level, I thought the Sonerai would be a good candidate for primary or even sportsman level acro. It is stronger than a Citabria and about the same power to weight ratio, solo.

 

[UpSideDownFlyboy]

Hello Dan,

I can't honestly say that I have ever tried to perform a routine in a Sonerai with the airshow box constraints. I was very lucky and did most of my aerobatics training with Bobby Younkins in a Super Decathalon and a Pitts S-2 when he had the school in Rogers, Arkansas, but most of my aerobatics are when I get bored between point A and B and decide to get a different perspective of the world. ;D I did read an article once about a man from Australia who installed a 100HP Rotax 912 in a Sonerai II Original and made his own inverted systems. He competed in the Sportsman class and did very well. Placed 3rd for the year if I remember right. Given the speed envelope of the Sonerai, I can't imagine that it would be any more difficult to stay in the box than in a Pitts. Sorry that I couldn't be of more help there.

Have Fun and Fly Safe!

 

[DanMcC]

Thanks for the reply Scott. Hopefully we we'll get to find out this summer.

 

[Schmleff]

I can tell you that I would be nervous to do a loop in my sonerai I. I would be concerned about the exit speed. Rolls are easy, but any time I point the nose down it accelerates very quickly.

When I do a flyby with a shallow decent to the runway, I pull the power way back and still end up over 190mph. I don't put the power back in until level.

However, when I used to fly with Drew Waterworth in his SII in formation the two planes were easy to keep together except for one part of the flight. When we would start to descend to land together, I could not stay with him unless he carried power. I say that to illustrate that while one Sonerai may be safe and not build up speed quick because of high drag, a clean one may get you in trouble.

I know Chad used to roll his IILS because I watched him do it while flying formation with him.

 

[Des]

Yes, aerobatics in a Sonerai are possible...but I would nobody advice to start experimenting with it BEFORE You are a well trained aerobatic pilot. Once one has a good level of aerobatic axperience, it is possible to perform some "limited" aerobatics in the Sonerai.
Nowedays I fly with a 2180 engine, with no inverted oil system. Before I had a 1835 in it with a modified oil sump and a Posa "carburettor" This setup gave me full engine power and oil pressure when inverted for up to 5 seconds. Following linked manouvres were possible with minimal loss of altitude: Loop/ stall turn RH / slow roll / cuban eight / Aileron roll / barrel roll / roll 45 degree climbing.
With proper control, none of these manouvres wil take You over 4 G's
Rolls to the right are working with the engine, but the stick deflection is limited. Also, I noticed too much "flex" on the eileron control.
I never did snap or spin the Sonerai, and I never intend to snaproll in a Sonerai.
After some time, I slowly but surely decided to do away with aerobatics in the Sonerai...Well, is there anywhere in the world a high time Sonerai with lots of acro hours..? I am convinced there is lots of intelligent people around in the world in search for a "budget" aerobatic aircarft, but aperantly, nobody seems to "discover" the Sonerai...
As far as my experience goes, yes, provided you are a proficient acro pilot, you can play around a little with a Sonerai, but will quickly discover its limits and have had it.
I now have about 1200 hrs in mine, and enjoyed all the time in it. I nowedays fly it hard, but straight, and hope to do so for still many years to come.