Re: Sonex High Wing!
Posted: Fri Mar 03, 2023 12:33 pm
by kuhtenia
<< I wish the plane was designed primarily around the Rotax engine… >>
As one of those watching the high wing development with interest, one particular reason is that the prototype is going to be using a UL Power engine. As a modern-but-still-air-cooled platform, the UL Power option might just represent a really great fit for those of us not particularly interested in the AeroVee/Jabiru choices. And with the factory having sorted out the UL Power FWF details, the builder should have a reasonably clear path to follow.
Hmm, I might just have to go to Oshkosh this year!
Re: Sonex High Wing!
Posted: Sat Mar 04, 2023 7:13 pm
by Eric W
I don’t think I’d be building a Highwing in addition to my Sonex, but I sold the Sonex 11 years ago, and the Highwing meets two things I’d like in an airplane now:
-
Easier in and out. When I gave rides in the Sonex, I was always concerned that someone would step on the flap, or just fall off the airplane entirely. I would give rides to fairly senior people who may not be the most steady on the ground, and to get them in/out of a low wing - step over the flap, step over the side, lower yourself into the seat - just isn’t super easy. It will be nice to open a large door (on each side!), sit down, and bring legs up and in. To this end, I’ll probably go with a “Y” center stick, though I had dual sticks in the Sonex.
-
Shade - at a fly-in, it will be great to set a chair under the wing and enjoy the shade while people pass by and talk airplane stuff.
I’m really undecided about engines at this point. I had the 3300 in the Sonex and the biggest issue was stopping the oil cooler and oil cooler hoses leaking. That’s not really an engine problem.
As for the gear, I’d be on-airport operations only, and if I wanted land-anywhere operations, this probably isn’t the airplane (see Zenith, 750 series).
I think the wing center section setup is really clever - gets the entire extended-range fuel system installed without the wing outer panels. I think I"ll like having the view down and to the sides - I took a LOT of air-to-ground photos from the Sonex, and the low wing isn’t the best for that.
Re: Sonex High Wing!
Posted: Wed Jun 28, 2023 10:02 am
by BRS
Any updates on the HighWing?
Is there a projected availability?
Re: Sonex High Wing!
Posted: Fri Jun 30, 2023 7:35 pm
by Eric W
I wouldn’t be surprised if there’s something posted later on July 23rd (factory open house day), unless they’re really trying to hold us in suspense until the 24th.
Re: Sonex High Wing!
Posted: Fri Jul 07, 2023 11:18 am
by grum.man
I’m getting excited at the thought of potentially seeing a prototype in 2ish weeks! Still a little bummed they didn’t design it to accept a traditional aircraft engine. Rotax is about the only other brand I would consider but they aren’t aerobatic so not a good fit for my wishes. Offer a taller gear and the option to run an O235 and I’m all in.
Re: Sonex High Wing!
Posted: Sun Jul 09, 2023 5:27 pm
by grum.man
Bummer, just saw the press release saying they will not have the prototype at Airventure.
Re: Sonex High Wing!
Posted: Sun Jul 09, 2023 5:40 pm
by Bryan Cotton
grum.man wrote:Bummer, just saw the press release saying they will not have the prototype at Airventure.
What press release?
Re: Sonex High Wing!
Posted: Sun Jul 09, 2023 5:51 pm
by Eric W
I got it via email, so maybe only sent to subscribers of the Highwing updates. It looks like a page from the “Hornets’ Nest”, but it’s not posted to the Highwing page there.
They emphasize working through supply chain issues to keep current customers supplied with parts & kits, as well as meeting the commitments of the Uncrewed Aircraft Systems side of the business, while also continuing to work additional analysis and structural testing of the new high-wing fuselage. I’m sure it will be a great product when they’re ready.
Re: Sonex High Wing!
Posted: Mon Jul 31, 2023 7:50 pm
by Eric W
I did the factory tour when I was at Airventure last week. There didn’t appear to be anything for the Highwing in metal yet, at least not that they spoke of. They did speak to pretty much all of the parts and airframes in progress - the unmanned/drone being built, a Jet quickbuild, the 2-place jet, etc. They did have a rendering of the Highwing on display at one of their CAD stations. I don’t know enough about it to say if there were any differences or changes from earlier information. It did look pretty complete on the screen - main thing that I could see to add would be maybe some composite fairings between the inboard end of the flap and the top of the fuselage.
Re: Sonex High Wing!
Posted: Tue Dec 05, 2023 6:53 pm
by Bryan Cotton
In light of the current troubles over at Vans, I think a slow rollout is not a bad thing.
Re: Sonex High Wing!
Posted: Tue Dec 05, 2023 7:55 pm
by BobDz
Bryan Cotton wrote:In light of the current troubles over at Vans, I think a slow rollout is not a bad thing.
Ditto
Re: Sonex High Wing!
Posted: Tue Dec 05, 2023 10:58 pm
by dboeshaar
BobDz wrote:
Bryan Cotton wrote:In light of the current troubles over at Vans, I think a slow rollout is not a bad thing.
Ditto
But the grief at Van’s is really not directly related to development. Bad primer, bad laser holes and supply chain grief is the trifecta of this disaster.
Sonex does not have this grief, right?
Dkb
Re: Sonex High Wing!
Posted: Wed Dec 06, 2023 12:14 am
by Bryan Cotton
dboeshaar wrote:
But the grief at Van’s is really not directly related to development. Bad primer, bad laser holes and supply chain grief is the trifecta of this disaster.
Sonex does not have this grief, right?
Dkb
Of course I have no clue as to what is going on. Either at Sonex or Vans. I get the feeling when I hear Sonex folks speak that they have enough irons in the fire and are trying not to overextend themselves. Not just now, but for several years. My hypothesis is that the issues at Vans are not just divine intervention, but there must have been some bad choices made. How do you make bad choices? In my own industry I have seen it happen when you are trying to do too much, too quickly, with not enough people.
Hopefully Vans bounces back. They are a great company, great airplanes, and a huge legacy. The homebuilt aircraft industry is small enough that it hurts to lose anybody. Here’s hoping that Sonex stays strong and weathers whatever comes.
Re: Sonex High Wing!
Posted: Wed Dec 06, 2023 3:13 am
by Skippydiesel
I see that High Wing (HW) has a max take-off weight (MTOW) of almost 600kg. (13223 lb)
This is great, as here in Australia that has been the MTOW for Recreational Aircraft Australia (RAA) registered aircraft, for many years.
My Sonex has a MTOW of only 522 kg (1151 lb) which makes it very marginal as a 2 person aircraft. A lot of fuel must be left out, making the aircraft only good for a 2 person, short local flight ie very poor/nil X country capability.
I asked Sonex for un upgrade to 600 kg (non aerobatic) specifically so that I could tour with wife/friend - was flat refused.
BUT
RAA has recently moved towards a MTOW of 760 kg (1676 lb) - Sonex HW needs to consider a higher MTOW if they want to stay competitive.
Re: Sonex High Wing!
Posted: Wed Dec 06, 2023 9:20 am
by Scott Todd
A typical Sonex weighs about 650 pounds. That leaves 500 for useful load. 16 gallons of fuel is 3 hours and around 400 miles for the Little JAB or AeroVee. This leave 400 for people. These are comparable to a Cessna 150. Slimming down to 2 hours range and 250 miles yields another 50 pounds for ‘Well Conditioned’ people. This seems more ‘normal’ than ‘marginal’.
I think the High Wing will exceed these numbers which should make it quite competitive in the market.
Re: Sonex High Wing!
Posted: Wed Dec 06, 2023 10:50 am
by Bryan Cotton
I agree with Scott, with the caveat that my Aerovee is slower (100 kts) and burns less gas (4gph). Of course if you have added enough extra stuff to exceed 700 lbs empty, it’s a different scenario. For long XC trips I ship my baggage UPS to be able to carry more gas. Haven’t done any long solo XC yet but that would leave tons of payload.
Re: Sonex High Wing!
Posted: Wed Dec 06, 2023 5:47 pm
by Skippydiesel
Scott Todd wrote:A typical Sonex weighs about 650 pounds. That leaves 500 for useful load. 16 gallons of fuel is 3 hours and around 400 miles for the Little JAB or AeroVee. This leave 400 for people. These are comparable to a Cessna 150. Slimming down to 2 hours range and 250 miles yields another 50 pounds for ‘Well Conditioned’ people. This seems more ‘normal’ than ‘marginal’.
I think the High Wing will exceed these numbers which should make it quite competitive in the market.
Your Sonex empty weight is aspirational, once you go past a very basic Aerovee powered Sonex.
My Sonex Legacy/Rotax 912ULS/Airmaster CS/wing tanks (100L) - tops the scales at 340kg (750lb) - result! it’s basically a single seater. Increasing the MTW (non aerobatic) to 600kg would change this.
Re: Sonex High Wing!
Posted: Wed Dec 06, 2023 9:12 pm
by Bryan Cotton
Skippydiesel wrote:
Your Sonex empty weight is aspirational, once you go past a very basic Aerovee powered Sonex.
My Sonex Legacy/Rotax 912ULS/Airmaster CS/wing tanks (100L) - tops the scales at 340kg (750lb) - result! it’s basically a single seater. Increasing the MTW (non aerobatic) to 600kg would change this.
I thought my Waiex was heavy - currently at 673 lbs. Would be interested to know how much of the 77 lbs delta between our aircraft is engine.
IIRC the 3300 weighs the same as the Aerovee.
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 3:50 pm
by peterp
Bryan,
I don’t think it’s the engine, the Rotax power legacy I built was 295 kgs or 650 lbs
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 4:59 pm
by Skippydiesel
peterp wrote:Bryan,
I don’t think it’s the engine, the Rotax power legacy I built was 295 kgs or 650 lbs
I am the finisher/completer of this Sonex/Rotax; Features that may contribute to its high empty weight:
30L x2 wing tanks & associated plumbing, fuel level sensors, fuel transfer pump + 40 L header tank in standard Sonex location.
Airmaster CS 3 blade propeller
Comprehensive anti corrosion undercoat - DeSoto & Alodine
Anti oil canning/noise insulation throughout
Leather covered seat cushions
HD baggage compartment
Wheel pants by Sonex(?)
Goodyear Flight Custom III 5.00-5 6 ply tyres
Toe brakes
Aviation Products tailwheel
Homemade engine cowling
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 5:47 pm
by Scott Todd
You make it sound like this is a design flaw or shortcoming of a Sonex. Clearly you built a single place airplane. John Monnett would cringe looking at that list. He probably would have recommended a different airplane had you told them you wanted all that stuff up front. I’ve owned two and flown 4 different Sonex’s. I’ve helped broker a few more sales. They were all around the 650 mark and nicely equipped. They all flew as advertised.
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 7:29 pm
by Skippydiesel
Scott -
I am the finisher/completer - I purchased an almost finished Sonex, that came with all that I listed. Some was already installed, some I installed.
Many of the additions, to basic/standard Sonex, are to make the aircraft more suited to Australian flying conditions.
As I understand it (?) , the US (home of the Sonex) is blessed with a fairly comprehensive airfield coverage, most of which are paved. The result is an aircraft with fairly limited range, small wheels and a reduced concern over internal noise (oilcaning/engine).
Australian airfields tend to be very far apart (except on the coast, where they are concentrated around major population centers), grass/dirt and have poor fuel availability
The first builder, of my aircraft, sought to address these shortcomings by having larger diameter wheels, greater fuel capacity and reduce the internal noise generated by unpaved strips.
Even the choice of the Rotax engine (reputation for reliability & fuel econamy) goes some way to Australianising the Sonex.
I agree that the CS prop is an overreach but boy does it help in achieving great all round performance. This combined with the Rotax frugal thirst, helps to acheive great duration /range.
The beauty of the home built is that it can be customised - why stick religiously to the plans?
I am disappointed at the empty weight of my aircraft. I had hoped that the wing tanks may allow for a higher MTOW but Sonex seem particularly resistant to any change in the basic design (look how long it has taken for Rotax to be, sort of,recognised).
Check out the RV12 (a competitor) Empty Weight 366 kg (740 LB) MTOW 599 kg (1320 LB)
Oh! and one other innovation - My Sonex is solid riveted throughout. I don’t know if this is weight neutral/light/or heavy but would hope adds to the structural integrity and the argument for a MTOW weight increase.
I also forgot the cowling - My Son designed & built it from scratch. It’s his first composite build, so is a tad heavy. We went for the scratch built to accommodate the Rotax & its cooling requirements, which includes a pilot activated (electric) cowl flap. I have a Sonex vertical split cowling (considerably lighter) which may, someday, be modified to replace the home built - we will see.
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 8:47 pm
by Scott Todd
Well that was a really good post 
It explains a lot. I see it all the time where people ‘mod’ homebuilts to make them ‘better’. Of course its all relative. ‘Better’ is not always 'better. As a Mechanical/Aerospace Engineer, I’ve helped homebuilders modify their Gross weights to accommodate situations like yours. However, in this case, I tend to agree with Sonex. It only has 98 Sq feet of wing. I’ve test flown them on hot days at gross and it can be marginal. The RV-12 has 127 sq ft of wing with loading around 10% less than a Sonex. It really shows in its performance.
The Sonex was meant to be a simple, easily built, minimal airplane. Yours has obviously diverged from this original intent. Good luck in your endeavours. Maybe a new build is in your future. There are lots to choose from. Maybe that Sonex HW will fit the bill
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 8:59 pm
by Skippydiesel
Hi Scott,
“I’ve test flown them on hot days at gross and it can be marginal.”
Ah yes! but did the aircraft have a Rotax 912ULS, powering a CS prop? AND might this have changed the[ i] “marginal”[/i] observation ??
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 9:09 pm
by Bryan Cotton
Skippydiesel wrote:Oh! and one other innovation - My Sonex is solid riveted throughout. I don’t know if this is weight neutral/light/or heavy but would hope adds to the structural integrity and the argument for a MTOW weight increase.
I used to work at Sikorsky and Schweizer as a helicopter engineer. I believe the aluminum rivets will be slightly lighter, and better in fatigue. They have a lower shear strength than our pops though. The key parts for structural considerations are the spars (already solid riveted), their attachment to the fuselage, and the tail.
I am sure the airplane is strong enough to go over weight. Maybe you don’t get the full 4.4G utility load factor. But you also get higher stall speed, etc.
Weight is the enemy.
Re: Sonex High Wing!
Posted: Thu Dec 07, 2023 9:38 pm
by Skippydiesel
Bryan/Scott
In Australia, the builder can nominate the MTOW, however I am not an engineer (farmer) so am reluctant to move above the Sonex nominated 522 KG MTOW.
FYI -In Australia, Sonex can be registered GA or RAA.
From my perspective, the main operational difference are;
GA allows easier access to CTA and the aircraft can be used for aerobatics. Annual airworthiness inspections are more expensive than RAA.
Having no interest in aerobatics and little need to enter CTA, I have gone with RAA, which forbids aerobatics. RAA is arguable cheaper all round, as the owner/builder is allowed to do all maintenance/inspections & membership includes third party insurance.
I mention the registration/aerobatic prohibition, as I would have expected that an aircraft stressed for aerobatics, would have the structural integrity (along with wing tanks/solid rivet construction) to allow for a higher MTOW.
Either of you guys wish to comment?
Re: Sonex High Wing!
Posted: Fri Dec 08, 2023 10:31 am
by Bryan Cotton
I personally would not fly a Sonex that heavy. Though I don’t think the wings or tail would fall off, what about the stall, climb, and approach speed? Those are going up. What about the landing gear? Will it be sufficient for that extra weight? I know a few people have bent their mains, and if you are flying out of rough fields or just do a particularly bad landing you are at risk there.
On a long x-c my son and I can take 14 gallons of fuel, or 3.5 hours worth. We tend to land with an hour’s fuel but that is still 250nm worth of range. That’s not enough?
Re: Sonex High Wing!
Posted: Fri Dec 08, 2023 11:07 am
by builderflyer
Skippydiesel wrote:Bryan/Scott
In Australia, the builder can nominate the MTOW, however I am not an engineer (farmer)
Either of you guys wish to comment?
Not either of the guys…but isn’t this the same airplane that the original builder thought, amongst many other things, that he knew better than the designer and that he needed to and, in fact, did change the angle of incidence of the wing? This is one of those airplanes that John Monnett would say “please don’t call it a Sonex”. Not meaning to offend you, but personally I would have passed on this purchase. Depending on what was or what is the actual desired mission of the original builder or yourself, there must have been a better alternative out there. Just my opinion.
Art,Sonex taildragger #95,Jabiru 3300 #261
Re: Sonex High Wing!
Posted: Fri Dec 08, 2023 12:45 pm
by Kai
My own polished Sonex Legacy dual stick tailwheel has fairly frugal instrumentation including a 40 l seat back auxiliary fuel tank, 5.00 tyres, an Icom 200 and a mode C transponder. With the Edge 915 ECI including oil and coolant, it puts 680 lbs on the scales. It was not always like that: it started out very basic with the small Shinn tyres and a Jab 22A, but no auxiliary tank. The result was 618 lbs. This only shows that you need to be extremely careful when you start loading on the goodies. The sword above your head are always those 1150 punds.
Re: Sonex High Wing!
Posted: Fri Dec 08, 2023 8:58 pm
by Skippydiesel
Bryan Cotton wrote:I personally would not fly a Sonex that heavy. Though I don’t think the wings or tail would fall off, what about the stall, climb, and approach speed? Those are going up. What about the landing gear? Will it be sufficient for that extra weight? I know a few people have bent their mains, and if you are flying out of rough fields or just do a particularly bad landing you are at risk there.
On a long x-c my son and I can take 14 gallons of fuel, or 3.5 hours worth. We tend to land with an hour’s fuel but that is still 250nm worth of range. That’s not enough?
All very good points -
Naturally I would expect higher stall & approach speeds , reduced climb & probably cruise (for a given power setting).
As a for undercarriage - bad landing are always a risk no matter the MTOW and although I am likely to be using dirt (grass/gravel) strips I would not expect them to present much more of a challenge than a paved strip - the bigger issue is the impact of rapid gear oscillation on the fiberglass wheel pants.
Very roughly, outer Sydney to outer Melbourne (I would not be using the international airports) is about 360 Nm. I burn ULP, not carried by most airfields. When on a long trip, it behoves me to carry as much fuel as I can. The alternative is to find a lift/hire a taxi, into the nearest town/petrol station, with two 20L collapsible fuel bladders - something I have done many times but can eat into the available flying hours.
Re: Sonex High Wing!
Posted: Fri Dec 08, 2023 9:21 pm
by Skippydiesel
builderflyer wrote:
Skippydiesel wrote:Bryan/Scott
In Australia, the builder can nominate the MTOW, however I am not an engineer (farmer)
Either of you guys wish to comment?
Not either of the guys…but isn’t this the same airplane that the original builder thought, amongst many other things, that he knew better than the designer and that he needed to and, in fact, did change the angle of incidence of the wing? This is one of those airplanes that John Monnett would say “please don’t call it a Sonex”. Not meaning to offend you, but personally I would have passed on this purchase. Depending on what was or what is the actual desired mission of the original builder or yourself, there must have been a better alternative out there. Just my opinion.
Art,Sonex taildragger #95,Jabiru 3300 #261
No offence taken.
I did have it checked out by an aircraft engineer - he was very complimentary regarding the quality of the build and saw no potential problem(s) with the 1.5 degree change in the wing, angle of attack/incidence. The aircraft flies and handels normally, has tested good for the designed stall of 40 Kn (flaps MTOW) & 150 Kn (true) high speed cruise 5450 rpm @ 5500 ft.
Don’t know the original builders intended mission but given the extra fuel capacity & the CS prop, would suggest the same as mine - long distance touring.
Alternatives/price range - I focused on finding a Europa XS/Rotax 912ULS - over two years, came close twice - no deal! Then Sonex came out of the blue - if you look past the fuselage construction, many similarities - so I purchased it.
As far as Mr Monnett - I would guess that every home build, has some degree of customisation/personalisation. Could be as small/insignificant as the paint job, right up a major change like a much larger engine. Lets face it Mr Monnett was no fan of the Rotax 9 range, so I am not surprised that he would disown anything outside his original concept.
Re: Sonex High Wing!
Posted: Fri Dec 08, 2023 9:32 pm
by Skippydiesel
Kai wrote:My own polished Sonex Legacy dual stick tailwheel has fairly frugal instrumentation including a 40 l seat back auxiliary fuel tank, 5.00 tyres, an Icom 200 and a mode C transponder. With the Edge 915 ECI including oil and coolant, it puts 680 lbs on the scales. It was not always like that: it started out very basic with the small Shinn tyres and a Jab 22A, but no auxiliary tank. The result was 618 lbs. This only shows that you need to be extremely careful when you start loading on the goodies. The sword above your head are always those 1150 punds.
So true.
I think if I had not purchased a Sonex with wing tanks, the back of the seat Aux fuel tank idea has a lot of merit. Likely lighter/litre capacity, than 2x 30 L wing tanks + plumbing/valves/sensors/etc & a simpler fuel transfer system - what’s not to like?
Probably hoping for divine intervention however, I am seriously considering having my Sonex reweighed - I just can’t get my head around its current empty weight.
Re: Sonex High Wing!
Posted: Sat Dec 09, 2023 12:32 am
by Kai
My seatback tank contains only 40l- however, I can´t recall I have ever topped it off (in case my CG calcs might be slightly on the optimistic side). I have done some flying out of Alice and Toowoomba- the flying we do up here is not totally unlike Down Under, while our distances are shorter we are often up in the mountains and experience local weather dramatically different from forecasts and a total nogo up front. The idea of not having anough fuel to turn around and return home, is a show stopper, and an off field landing would surely put a lid on everything! We seldom plan for more than 3 hours flight, for which the Edge would require something slightly short of 50l. Then we have the mandatory reserve-we don´t feel that 40l is too much: but of course no luggage back there! In short it works, but it is not ideal.
Re: Sonex High Wing!
Posted: Sat Dec 09, 2023 8:06 pm
by Skippydiesel
Scott/Bryan,
You have both made some good points, regarding Sonex MTOW increase but somehow I feel you have not followed up with the rest of your argument.
Given that this aircraft is designed to put up with the stresses imposed by amateur aerobatics:
How can a plus 78 kg ( 600 kg) MTOW be of any concern, when the aircraft is flown in the “Utility” configuration. and assuming it has been loaded within CG considerations ??
The engine/prop are certainly able to deliver sufficient thrust for TO & sustained flight (check out all the other Rotax 9 powered aircraft).
As unrecarrages are constructed, with considerable overcapacity, specifically to withstand the occasional botched landing, can it not be assumed that a mere increase of 78 KG can be accomodated??
What remains is the ability of the aircraft to fly at this higher weight - will the lifting surfaces be sufficient, at a high density altitude, to achieve/sustained controlled flight ??
Re: Sonex High Wing!
Posted: Sat Dec 09, 2023 9:11 pm
by Bryan Cotton
That’s beyond my current skill level and bandwidth to analyze. I’d say the burden is on the person who wants to exceed the GW to prove it’s good, rather than the person who thinks the manufacturer’s GW is a good limit.
Re: Sonex High Wing!
Posted: Sun Dec 10, 2023 2:31 am
by Kai
When this new 600 kg MTOM for the new sports class came up un Europe, all aircraft owners deluged the manufacturers with requests for raised weights. I was lucky enough to get in touch with Kerry. The essence in his reply was that they did not know- it had never been tested (apart from the static spar loading). It might be possible, but he asked me to bear in mind that the factory limit was by no means only structural. Flight performance also came into it- takeoff, glide ratio, landing characteristics, to mention a few. Tongue in cheek he informed me that Sonex was in no way unwilling to set up a test program to find out, as long as someone else footed the bill. We left it at that. I miss Kerry- he was great!
Re: Sonex High Wing!
Posted: Fri Dec 15, 2023 6:56 pm
by Murray Parr
Skippydiesel wrote:
Kai wrote:My own polished Sonex Legacy dual stick tailwheel has fairly frugal instrumentation including a 40 l seat back auxiliary fuel tank, 5.00 tyres, an Icom 200 and a mode C transponder. With the Edge 915 ECI including oil and coolant, it puts 680 lbs on the scales. It was not always like that: it started out very basic with the small Shinn tyres and a Jab 22A, but no auxiliary tank. The result was 618 lbs. This only shows that you need to be extremely careful when you start loading on the goodies. The sword above your head are always those 1150 punds.
So true.
I think if I had not purchased a Sonex with wing tanks, the back of the seat Aux fuel tank idea has a lot of merit. Likely lighter/litre capacity, than 2x 30 L wing tanks + plumbing/valves/sensors/etc & a simpler fuel transfer system - what’s not to like?
Probably hoping for divine intervention however, I am seriously considering having my Sonex reweighed - I just can’t get my head around its current empty weight.
My Waiex is disappointingly heavy. 335 kg (739lbs) with the supposedly lighter Rotax up front and I never added many extras. I am suspicious of how the main gear legs that seem to pull inwards after rolling forward might be putting extra pressure on the scales (I first noticed this when jacking up a main wheel and was surprised at how much the gear moved sideways once the wheel left the floor surface). Wondering if you are meant to relieve this pressure to get an accurate reading, anybody have any thoughts on this?
Re: Sonex High Wing!
Posted: Fri Dec 15, 2023 7:51 pm
by Bryan Cotton
Murray,
Where I used to work they had a sign on the wall : “One test is worth 1000 expert opinions.”
My expert opinion is it won’t make a ton of difference but you could test it.
