sonex performance

[Jay]

Response to Mikek ( welcome forum )

 

Good points - high speed , aerobatic, low build hours, low cost ( esp with Aerovee)

 

Bad points - safety( fuel tank between you and donk combined with bubble canopy in event of forced landing tipover- esp you have trainer wheel - equals poor escape scenerio) , limited range esp with 3,3 Jab.

 

 

[Guest Qwerty]

Response to Mikek ( welcome forum )

......... in event of forced landing tipover- esp you have trainer wheel - equals poor escape scenerio) , limited range esp with 3,3 Jab.

Sonexes have conventional undercarriage don't they?.....no trainer (nose) wheel.

 

Cheers.

 

 

[Jay]

They have both options

 

 

[Guest mikek]

Reply to Jay re Sonex

 

Ah ha, found you again Jay- can't see how the last post could cause a problem seeing it was the first intro!! Never mind, I also got a $150 speeding ticket last night so the feds were on my case! Thanks for the pointer on fuel/escape route, that hadn't occurred to me. I think the range and payload restrictions will count it out for Africa, its a long way between fuel stops in many areas. Plus my mate who will fly with me a lot weighs 120kg - probably need a C 206!

 

 

[Jay]

Yes, my view is that it is an adrenalin machine for burning around the district playing fighter pilot , not a commuter - the Sonex site 'Reality Check' is honest in their evaluation. It may pay you to get their CD.

 

From my perpective I don't like fuel in the cockpit, the small Jab's worried me in this respect when I used to fly them

 

 

[Guest check-in]

My taildragger Sonex with no wheel spats or fairings and 8 inch wheels running boat trailer tyres (the cheapest way I could find tough tyres to fit the narrow wheels) is maybe not as streamlined as the designer intended. But with a Jab 2200 it will give you 300 nm still air range with a fat 45 minutes reserve. At 2850 rpm and 15 lt per hour it cruises about 105 in summer, 110 in winter.

 

The weakest part of the whole design is the canopy, which is just too light and is always cracking due to the flexing which can not be avoided when opening and closing it. The fuel tank location is a worry, but its location is not unique to this design. Tiger Moths, Austers etc could give one a good soaking of fuel in a crash, too, and if you invert any Cessna and it starts to burn, you'd better get out pdq.

 

It has quite a substantial roll cage behind the seat, so it should be possible to crawl out from under in the event of nosing it over. As good as a Cherokee or similar, I should think. Which is not to say as good as some high wing designs.

 

But it is a compact little beast more suited to a couple of lightweights. I am 80 kg and my wife 60 kg, so we are reasonably comfy in it, but a couple of big guys wouldn't last long in the cockpit without cramping up. Legroom is good, so one big guy and a toothbrush would be fine. The tailwheel configuration with the oversze wheels I fitted can handle surprisingly rough and soft strips, but a bush plane it ain't.

 

That performance on such little fuel will always come with some compromise.

 

 

[Jay]

Thanks for that Check -In, good, helpful information. Be very intersested in your decision process to go Sonex

 

 

[Guest check-in]

Well, it had to be low wing, tailwheel and affordable. Originally I wanted a Jodel, but then realised that wood and fabric would be fraught with hidden problems as most Jodels out there are fairly old. Then I had the hots for a Sonerai, until I saw how small the cockpits were. This would still be my second choice if it had anything other than a VW engine, but that's another debate.

 

I looked at a few Sonexes while I was in the USA about a year ago and it was love at first sight. All metal, reasonable performance and a bit of space for baggage. Easy to maintain and in VH or USA 'N' experimental rego, legal for aerobatics, so obviously strong. Sure, they look as if they have been hit with the ugly stick, but not as bad as some. Anyway, we all know the ugly ones are often the best goers.

 

And so it has proved.

 

 

[Jay]

Thanks again Check in - I would LOVE to know why you discarded the Aerovee option

 

You Sonex must look fugly with those big feet!

 

 

[Guest check-in]

Actually the big wheels look OK. It's fugly full stop and anyway who looks at their feet when the face stops you in your tracks?

 

I was not keen on any of the VW options only because they are not purpose designed for aircraft and according to one website I visited really don't put out the claimed H.P. Also heavier than the Jabiru. Not to say they are not OK for someone whose budget won't run to the more expensive Jabiru option, just so long as they go in realising that they will have to live with the compromises like unkown overhaul life, possible cooling problems etc.

 

At the time I went into the Sonex, I had virtually NO knowledge of the Recreational scene, having always flown certified aircraft (right up to Mr Boeing's products). So I just naturally wanted to stay with the technology I understood, i.e. certified engines. Not that I think the Jabiru is as robust as a Lycoming or Continental and whether it is as good as a Rotax probably depends a bit on luck - whether you get a Friday engine or a Tuesday one. The Rotax wasn't an option for the Sonex as the designer insisted on air cooling for 'simplicity' and light weight.

 

Plenty of debates on the merits or otherwise of VW conversios on Google search.

 

 

[Jay]

My final thanks for picking your brain and experience- yes, recreational aircraft are one of the great comprimises beteen safety, reliabilty and performance that we have to make. Certification is not an option due essentially to the fanatical focus on weight. At the end of the day, Jabiru have a reasonable engine product even if the 3.3 overheats in summer and won't start easily in winter ( don't know much about the 2.2), the engineering detail on their airframes is abysmal, and the technical support is cavalier.

 

The Rotax is another story; what a choice we have, the new 0 -200 Continental is still too heavy and expensive

 

Enjoy your Sonex; as you say the ugly ones are the best goers

 

 

[Vorticity]

I feel filthy doing this but I have to defend jabiru here.

 

Engineering data. I don't blame jabiru for being tight. Why do you need detailed engineering data? Are you qualified to interpret it? Zenith where very open with information for the 701.....worked great for ICP, now we have the Savannah!

 

2. Engine support, try getting detailed fault finding support out of rotax in Australia. Responses such as 'the 912 doesn't have that problem' to an owner doesn't do it for me. The one thing that all the jab owners in my club rave about is the responsive support.

 

 

[Guest check-in]

I have operated the Sonex in ambient temps of over 40 deg C and not had a problem with cylinder head temps on the Jabiru 2200. The oil is run through a cooler which may be a little small for the job, but it (just) stays under the redline in those extremes if I keep it filled to 2 litres. That is - I do NOT fill it to the 2.3 litres it is supposed to hold.

 

However, I would not want a lengthy taxi in such extreme temps. About 3 to 5 minutes is all, then GO. When it's hot like that, cruise-climb at 90 knots/3000 rpm also helps. That is almost full throttle, so hopefully the mixture is nice and rich up in that range.

 

 

[Jay]

Sonex stuff - of interest to SOME may be the ONEX currently under development, a single place Arovee ( 80 HP) powered aerobatic quick build kit for abot $40k total ( my estimate )

 

 

[Guest dad]

Even better

 

Embed Code Viral Player

 

Dad

 

 

[moz]

Onex

 

Sonex stuff - of interest to SOME may be the ONEX currently under development, a single place Arovee ( 80 HP) powered aerobatic quick build kit for abot $40k total ( my estimate )

On the Sonex site they are now quoting around 20-22K USD for the Onex........

 

 

[Guest dad]

Maybe i should rename that link I posted?

 

Google 'Embed Code Viral Player' it is not what you think, John Monnet being interviewed about the turbo option for the Aerovee.

 

Horsepower wise the veedubb modders have been known to cut it with the best.

 

They have been around for a long time and parts and repairs are modestly priced to say the least.

 

With Sonex behind this turbocharging option I feel safe in the knowledge that it will not overstress the engine and give the aircraft even better performance.

 

With this development in mind I can only hope the offer the folding wing option for the other models.

 

Peter

 

 

[Brett]

From a group email I received from Sonex the other day I think they will never offer the folding wing option on the other models. The turbo option does sound cool but as it can be fitted onto any aerovee engine even previous versions.

 

 

[Jay]

With the USD/AUD exchange rate now , probably AUD $ 30k is a good estimate for the Onex. However may be looking at least 6 months to get testing, US accreditation and kit manufacture done. Then there is the RAAUS accreditation to do, plus a backlog factor on orders... so a long wait for those that are interested

 

Not sure that turbo 100 hp is necessary for the Onex, may be for the Sonex?

 

 

[Vorticity]

Sonex say it will be available for aerovee and 3300 but not the 2200. Given the performance of the 2 seater, can you imagine the performance with 120hp up front?! With folding wings it could be a nice second aircraft for aeros (VH experimental)

 

I reckon 5 years till it would be a good option, hopefully I'll be finished my sonex and have some good hours on it by then

 

 

[Guest dad]

Vorticity,

 

what stage are you at with your sonex?

 

Peter

 

 

[Vorticity]

I have the tail, control surfaces, left wing and I'm into the right wing.

 

 

[Guest dad]

I'd love to see your progress.

 

Any chance of a sticky beak at it?

 

Peter