Sub-Sonex micro jet homebuilt released

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http://www.sonexaircraft.com/subsonex/index.html

In conjunction with EAA sport av mag, Sonex has gotten to the point with their mini jet plane that they are starting to take position deposits.

Why is this different than other companies that have done similar? Well, the sub-Sonex is a real plane, with real flight times, coupled with a company and CEO that has a long history of delivering product.

Since my first ride in a Sonerii back in the late 80s I've been a fan of Monnett designs. Good article in EAA sport av too. Looks like it could be another winner. My only minor complaint is I was expecting a bit more cruise speed, but it's limited to 18k' at this time. Maybe if they could get up into the levels it would go a bit faster. However, it's a constant chord wing, with pretty simple assembly in keeping with Monnett themes.

No affiliation.
 
Wow, thats a really neat idea, if they could just stretch the range a little bit (they did add fuel it appears, up to 44gals from 32gal) and useable load, a big guy like me needs a little more carrying capacity.

Although I wont lie, it wouldnt be for just flying around, i'd want to fly to work 300sm and would need about 75lbs of baggage.

Wishful thinking!


P.S whats up with the ultra long wheel pants? Would be kinda nervous landing on them, one bounce and you might rip one off....
 
It's RG, so - no wheel pants. The first prototype had a mono-wheel with a fairing but the kits will have a dual tire trike RG landing gear.
 
Wow, thats a really neat idea, if they could just stretch the range a little bit (they did add fuel it appears, up to 44gals from 32gal) and useable load, a big guy like me needs a little more carrying capacity.

Although I wont lie, it wouldnt be for just flying around, i'd want to fly to work 300sm and would need about 75lbs of baggage.

Wishful thinking!


P.S whats up with the ultra long wheel pants? Would be kinda nervous landing on them, one bounce and you might rip one off....

Nope, you could not use it for your intent, it's Experimental Exhibition.
 
I still think this is still somewhat of a novelty. You can get a lancair, glasair or RV with much more efficiency. Small format jet engines just don't work well.


Sent from my iPhone using Tapatalk
 
I still think this is still somewhat of a novelty. You can get a lancair, glasair or RV with much more efficiency. Small format jet engines just don't work well.


Sent from my iPhone using Tapatalk

Not much efficiency out of a turbojet limited to 18,000 feet. Looks fun though
 
I wonder how loud that thing is. The engine is advertised as a pure turbojet, and historically they've been quite loud.
 
http://www.sonexaircraft.com/subsonex/index.html

In conjunction with EAA sport av mag, Sonex has gotten to the point with their mini jet plane that they are starting to take position deposits.

Why is this different than other companies that have done similar? Well, the sub-Sonex is a real plane, with real flight times, coupled with a company and CEO that has a long history of delivering product.

I love the Sonex family of products, and built most of a Sonex before buying my CTSW. I have seen the SubSonex in person. It is very cool, but not exactly "practical". It has a 32 gallon fuel tank, and burns 32 gallons per hour. With VFR reserves, that's 30 minutes of flight time and at 250mph that gives it less than 125 mile range when you consider taxi and climbout. Not exactly "real flight times". If you owned one in Florida and wanted to fly it to Oshkosh...how many stops would that take and how much fuel? I also don't think it has any baggage capacity, maybe 10lb or so in the nose.

When I asked John Monnett about why he built it, he gave an honest answer: "Because I always wanted to fly a jet, and jets are cool!" It's really a fun "around the patch" toy, it's not a serious attempt to make a practical personal jet.

EDIT: I see somebody mentioned fuel is now up to 44 gallons. That is still only 45min flight time with reserves. Again, not practical for travel...but a hell of a lot of fun, I'm sure!
 
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Yeah, after reading the article in EAA, it's not as useful as I first thought it might be. The EX-X rather than EX-AB is a killer.

I don't get why the FAA has their panties is such a bunch about it just cause it's a pure jet. From all I've heard and seen the single lever jet control is much easier than piston. Make it just like any other single engine homebuilt and let the people who build it decide on the flight envelope. The requirements for O2 are there, the requirements for FL180 and above are in place, so why all the heartburn about a pure jet? If they can go into the FL space, and meet the req then do it EX-AB. It's BS.
 
Yeah, after reading the article in EAA, it's not as useful as I first thought it might be. The EX-X rather than EX-AB is a killer.

I don't get why the FAA has their panties is such a bunch about it just cause it's a pure jet. From all I've heard and seen the single lever jet control is much easier than piston. Make it just like any other single engine homebuilt and let the people who build it decide on the flight envelope. The requirements for O2 are there, the requirements for FL180 and above are in place, so why all the heartburn about a pure jet? If they can go into the FL space, and meet the req then do it EX-AB. It's BS.

I believe the reason it's in EX-X is that it violates the 50% rule. Sonex made the decision to only offer it in nearly complete form, so don't blame the FAA.

I love the Sonex family of products, and built most of a Sonex before buying my CTSW. I have seen the SubSonex in person. It is very cool, but not exactly "practical". It has a 32 gallon fuel tank, and burns 32 gallons per hour. With VFR reserves, that's 30 minutes of flight time and at 250mph that gives it less than 125 mile range when you consider taxi and climbout. Not exactly "real flight times". If you owned one in Florida and wanted to fly it to Oshkosh...how many stops would that take and how much fuel? I also don't think it has any baggage capacity, maybe 10lb or so in the nose.

When I asked John Monnett about why he built it, he gave an honest answer: "Because I always wanted to fly a jet, and jets are cool!" It's really a fun "around the patch" toy, it's not a serious attempt to make a practical personal jet.

EDIT: I see somebody mentioned fuel is now up to 44 gallons. That is still only 45min flight time with reserves. Again, not practical for travel...but a hell of a lot of fun, I'm sure!

That AOPA article I referenced says to figure around 22 gallons an hour, you could figure one hour enroute per leg, and you'd have to stop at airports with Jet-A. What are the XC restrictions on aircraft in EX-X?
 
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What are the XC restrictions on aircraft in EX-X
Depends on what is written up. The EX-X sailplanes get an area of a few hundred miles around their declared home airport and they are supposed to fax in a letter to the FSDO to fly elsewhere. Note it isn't permission to fly elsewhere, it is notification.
 
The requirements for O2 are there, the requirements for FL180 and above are in place, so why all the heartburn about a pure jet? If they can go into the FL space, and meet the req then do it EX-AB

I'm with you there... I wonder what kind of fuel burn, speed and range it would get at 25,000 feet? Probably good enough to make it practical. Would love to stuff the panel with some inexpensive experimental avionics and an autopilot.

One problem with the design and altitudes above 18,000. Once you get into the mid twenties in an unpressurized airplane, you need a good sealing face mask. You also need extra training and caution - you can get the bends (among other aeromedical concerns) if you don't do everything right.

Perhaps Sonex thought that with the small and light design of the airplane (proper O2 system) and the track record of E-AB accidents that they would just rather not mess with it.

Keeping it at or below 18,000 allows pilots to use a simple cannula system and reduces their liability.

Flutter could also be a concern.
 
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I believe the reason it's in EX-X is that it violates the 50% rule. Sonex made the decision to only offer it in nearly complete form, so don't blame the FAA.

I doubt that the FAA decided to build/release it in over 50% form. I'm pretty sure that decision happened inside Sonex. Could it be 51% built outside of Sonex? Based on what I see there, the plane is bone simple comparatively speaking, and that falls in line with Monnett's design philosophy.

So, yes - I can blame Sonex for that. the entire plane is built off the designs of the early Sonex with some modest airframe mods. The engine is the only thing that's different.

Where the FAA has their panties in a wad is the op-spec. Requiring a type cert? That's BS.
 
That AOPA article I referenced says to figure around 22 gallons an hour, you could figure one hour enroute per leg, and you'd have to stop at airports with Jet-A. What are the XC restrictions on aircraft in EX-X?

My 32gph number comes from what John Monett told us at the Sonex Builder Workshop when he pulled it out and started it up for us to gawk over. It's certainly possible they got the fuel consumption down or are using a different engine, since my viewing was about three years ago.

BTW, that little jet engine was insanely loud for its size. I know, all jets are loud, but it seemed disproportionately so. :yesnod:
 
So, yes - I can blame Sonex for that. the entire plane is built off the designs of the early Sonex with some modest airframe mods. The engine is the only thing that's different.

That's not true, look at the airframes...the Sonex is much wider, since it's designed for two seats side-by-side. The SubSonex is shorter as well. The Sonex has a Vne of 197mph, which is lower than the 250mph cruise speed of the SubSonex.

The SubSonex airframe is closer to the Onex single seat, but it's not the same as that one either. It's a new (but similar) airframe to other Sonex designs.

It seems silly that Sonex is not offering a 51% build, especially since they are now shipping quickbuild kits for the Sonex that are 51 compliant and have all major assemblies (fuselage, tail, wings) complete. There must be something about all the engine, avionics, and fuel systems the company does not want builders getting wrong.
 
That's not true, look at the airframes...the Sonex is much wider, since it's designed for two seats side-by-side. The SubSonex is shorter as well. The Sonex has a Vne of 197mph, which is lower than the 250mph cruise speed of the SubSonex.

The SubSonex airframe is closer to the Onex single seat, but it's not the same as that one either. It's a new (but similar) airframe to other Sonex designs.

It seems silly that Sonex is not offering a 51% build, especially since they are now shipping quickbuild kits for the Sonex that are 51 compliant and have all major assemblies (fuselage, tail, wings) complete. There must be something about all the engine, avionics, and fuel systems the company does not want builders getting wrong.

What's so difficult about the build process? It's measure, cut, cleeko, rivet, next. Just because the panels are different size or shape, the build process is exactly the same. No moulding, curing, pressing, autoclave, etc. The retract is new, but it's all bolt, nut, actuator. The speed is higher, but it's not that much higher, so weigh your flight controls, and balance accordingly. I've done the flight controls on a Bonanza, and that was dead simple.
 
What's so difficult about the build process? It's measure, cut, cleeko, rivet, next. Just because the panels are different size or shape, the build process is exactly the same. No moulding, curing, pressing, autoclave, etc. The retract is new, but it's all bolt, nut, actuator. The speed is higher, but it's not that much higher, so weigh your flight controls, and balance accordingly. I've done the flight controls on a Bonanza, and that was dead simple.

I agree, that's why I'm guessing there is something other than the airframe that requires some specialized skills. Keep in mind Monett lost his first company to a lawsuit, he's very liability-shy.
 
I agree, that's why I'm guessing there is something other than the airframe that requires some specialized skills. Keep in mind Monett lost his first company to a lawsuit, he's very liability-shy.

Maybe he's the force behind the type cert mandate. That would be unpleasant to learn about.
 
those wheel pants look terrible

One more time with vigor. There are NO WHEELPANTS on the new build model, just on the first prototype. Please read and follow label directions, Things in mirror are closer than they appear, contents may have settled, may result in anal leakage.:mad2:
 
Maybe he's the force behind the type cert mandate. That would be unpleasant to learn about.


What type cert mandate? From Sonex's web site:

Because there is no Type Certificate available for the SubSonex, pilots will need a Letter of Authorization (LOA) from the FAA that is specific to the aircraft.
 
may result in anal leakage.:mad2:


Watch out, you may be from central california and be one of those "guzzlers" with that type of remark.... lol :idea::idea:


But yea, I see what your saying, in the video it had the wierd and ugly looking wheel pants, but they have since came out with a new version. Got it.
 
What type cert mandate? From Sonex's web site:

The LOA is a bypass of the FAAs mandate that pilots of turbojet engine aircraft have a tiered type cert. So - you are correct sir, a type certificate is NOT a requirement due to the plane being EX, so long as one gets the LOA for this specific airframe.

Guess what the requirements for the LOA will be? I suggest you look at the curriculum for - you guessed it, a type certificate for turbojet aircraft.

congrats...:idea:
 
The LOA is a bypass of the FAAs mandate that pilots of turbojet engine aircraft have a tiered type cert. So - you are correct sir, a type certificate is NOT a requirement due to the plane being EX, so long as one gets the LOA for this specific airframe.

Guess what the requirements for the LOA will be? I suggest you look at the curriculum for - you guessed it, a type certificate for turbojet aircraft.

congrats...:idea:

That remains to be seen.

I've never flown a jet, but from what I understand from those who do, is that the propeller on a piston powered aircraft, and particularly on a turbine powered one provides a good bit of braking, whereas a jet is always pushing. Other than that, jets are simpler to fly. I could see someone coming up with a curriculum in a complex piston plane that would include approaches and landings with a minimum level of power enforced.

My guess is that the flight characteristics of a SubSonex won't be all that close to any of the business jets and dual in one of them won't help. I also suspect whatever the FAA comes up with, any potential insurance carrier will expect more.
 
One more time with vigor. There are NO WHEELPANTS on the new build model, just on the first prototype. Please read and follow label directions, Things in mirror are closer than they appear, contents may have settled, may result in anal leakage.:mad2:

Relax! Psycho, I read they were updated I was commented on the video through the link.
 
No restrictions on where you go, just notify the home base FSDO. I owned an EX-X, CC was not an issue at all.

It may seem subtle, but asking permission every time you want to fly somewhere would get old about the 2nd time I had to do it. One day, one guy at one FSDO could just reply "negative authorized flight" and that would be the end of that. Might seem like a small leap to you, but to me it's a complete unbridgable gulf.
 
No restrictions on where you go, just notify the home base FSDO. I owned an EX-X, CC was not an issue at all.

Jet or recip? The rules are different for the two. The issue is not where you can go, but WHY you are going there.
 
Yeah, after reading the article in EAA, it's not as useful as I first thought it might be. The EX-X rather than EX-AB is a killer.

I don't get why the FAA has their panties is such a bunch about it just cause it's a pure jet. From all I've heard and seen the single lever jet control is much easier than piston. Make it just like any other single engine homebuilt and let the people who build it decide on the flight envelope. The requirements for O2 are there, the requirements for FL180 and above are in place, so why all the heartburn about a pure jet? If they can go into the FL space, and meet the req then do it EX-AB. It's BS.

Probably the response time of the engine when you apply power.
 
Probably the response time of the engine when you apply power.

Yeah, maybe. Seems like a big leap from no prior restraint(piston), all the way to type cert/LOA, but that might be the basis.
 
Yeah, maybe. Seems like a big leap from no prior restraint(piston), all the way to type cert/LOA, but that might be the basis.

You have to also remember as well that the FAA does not make a distinction in weight/power categories with pure turbojets. BTW, Type Ratings are what pilots get, Type Certificates are what planes get.
 
You have to also remember as well that the FAA does not make a distinction in weight/power categories with pure turbojets. BTW, Type Ratings are what pilots get, Type Certificates are what planes get.

Ratings - my bad.
 
$125K for single seat airplane with a 200nm range, no thanks.


The AOPA article suggests a cruise of 190 mph at 18 - 22 gph, depending on altitude. Allowing for climb, descent and reserve, 200 nm might be only doable on a still wind day.

According to Sonex, the VW powered Onex is good for 155 mph at altitude, and has a range of more than 500 miles. If you're actually going somewhere, that sounds like a better option.

If that jet is as noisy as I think it might be, I can see it being prohibited at a lot of airports. Some things just don't scale down well.
 
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