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Next RV model. The RV-1010

Denok

Active Member
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The next RV should be a twin IO-360 powered aircraft with available FIKI. It should be the size of a 10 and a good IFR plateform.
There...I said it.:p
 
For what gain?

So you are looking for a 4 place twin based on the -10.

What is to gain? It will be substantially heavier, burn more fuel, and likely have the same Vne...
 
...and will cost 10 times as much to build as any of the plethora of light twins at any airport in America can be purchased for today.
 
Take a look at the Velocity V-twin. Really cool airplane but two of everything and twice the aggravation to sort out.
 
Likely wouldn?t be enough demand to design, produce parts and maintain support. A high-wing back country/float capable design might have wider appeal. Just sayin.

Bevan
 
But if you loose one of the engines, the one still running will get you to the scene of the crash! :D
 
Yes, and couple that with the fact that a twin has twice the chance of losing an engine. A twin really needs to be able to perform (continue to destination) on one engine to be considered superior to well designed and maintained single. IMHO.

Bevan

But if you loose one of the engines, the one still running will get you to the scene of the crash! :D
 
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Twins

I always loved the Wing Derringer...too bad they are a pretty rare bird.

Twin Comanches are nice but probably the biggest bang for the buck is a mid 60's C-310...
 
I'm holding out for the RV-20. Six seats, engine options: single Lycoming iE2 or PT-6. VNE 350 kt (level flight achievable). Factory wing hardpoints for drop tanks / JDARC (Joint Direct Attack Rubber Chicken) pods.
 
Take-off Performance

A good twin needs to be able to take-off with one engine. All the airliners are capable of continued take-off past a certain point during the ground roll. That second engine is of no use if it takes you to the tree line at the far end of the airfield and the rejected take-off puts you into the ravine.

A 6 seat twin likely needs a 250-300hp per engine to achieve this, depending on the aerodynamics and pilot technique. A 4 seat twin likely needs IO-390s. An automatic propellor feathering device would certantly help as well, although that's pretty complex to design properly.
 
Twins. Nah.

My $.02, worth $.01. After 40-odd years in the little airplane business, I’ve only seen one light twin that I’d even consider owning. The Wing Derringer had 160 hp per side and only two seats, which might provide some useful climb performance on one motor. When Piper, Beech, Champion or Grumman made twins out of existing singles (Twin Comanche, Seminole, Duchess, Lancer, Cougar), they ended up with multiengine trainers, not better versions of the airplanes they started with. (eell, the Twin Comanche wa a bit demanding for s trainer) Airplanes designed as light twins from the start fared only a little better. I believe current piston engines lack the power to weight ratio to do an adequate job. Building a twin from even a well-executed kit is nothing I’d ever consider. I love our RV-6.
 
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twins

I had a 1964 Cessna 320 Sky Knight. It flew great on one engine; fast and roomy...

The C-310R is a really nice twin, too. It also flew fine on one engine.

Now the early model Apache...not so much...
 
Stay single...

A good twin needs to be able to take-off with one engine. All the airliners are capable of continued take-off past a certain point during the ground roll. That second engine is of no use if it takes you to the tree line at the far end of the airfield and the rejected take-off puts you into the ravine.

A 6 seat twin likely needs a 250-300hp per engine to achieve this, depending on the aerodynamics and pilot technique. A 4 seat twin likely needs IO-390s. An automatic propellor feathering device would certantly help as well, although that's pretty complex to design properly.

I think you may mean that a good twin needs to be able to climb on one engine. I do not believe there is a certified twin, piston or jet, that allows take off with one engine inoperative, but your point is valid.

The early Apaches defined the often repeated joke about "flying you to the scene of the crash" as its single engine ceiling was near sea level. The B58 Baron, on the other hand, has about a 9,000' single engine ceiling. I've have had an engine failure in flight in my Baron and simply feathered the prop and continued to the nearest field to an uneventful landing, no crash involved. There's no way to know how often those events happen as it's not required to be reported, but I imagine it's a recurring event. If you're trained and proficient, it's not a big deal. If you're not prepared, it is absolutely unforgiving and deadly.

The 6 seat aircraft you've spec'd is a solid Baron and the 4 seat would be a Piper Commanche. Both good, stable twins. The issue with them is that they're not experimental nor inexpensive to own and operate (I owned a B58 Baron for many years and still have the mental scars of parts and labor costs {side note, I was weighing the cost of a custom made SkyDynamics sump and intake and then remembered it cost almost $7,000 for a new starter adapter for an IO-550 on the Baron [that's not the starter, just the Rube Goldberg gearbox that the starter mounts on], and suddenly, that cold air intake with sump seemed inexpensive. Yeah, I bought it}). And although fuel isn't actually twice the cost, it's a lot. I owned a Bonanza and a Baron and I can tell quite accurately that a B58 fully loaded is about 36% more expensive in fuel than a fully loaded A36 Bonanza when calculated block to block. Those two airplanes share a common airframe design and are about as good an example of what you could expect by comparison if the RV-10 became a twin, although a comparison of the Velocity versus Velocity V-Twin is another good one and experimental too; I just don't have hands-on experience with both like I do the Beech's to provide meaningful data.

The thought of a twin RV-10 is interesting though. If you're thinking to go faster, or just thinking twin engine to have the extra engine in terms of flying over the mountains, at night, in IMC...the trifecta of instrument aviation - you should consider the Velocity V-Twin. It's about $250K+ to build and a lot more hours (and I hope you enjoy composite work...), but it is very nice airplane. I came very close to buying a kit a couple years back, but then decided on the 10 after meeting with a couple V-Twin builders and coming to the conclusion that it will take closer to 4,000 hours to build (and I'm hoping to be flying it with a little life left to enjoy it). It would be fun to have though, if you can get past the construction time and cost.

Second side note: I laugh when I read folks talking about cost cutting on their airplane builds, saving $10 here and $50 bucks there - all the time I'm thinking that buying
"expensive parts" for an experimental airplane compared to parts from Beechcraft is like comparing getting hit with a fly swatter versus a sledge hammer. Aside from the idea that penny pinching on an airplane that may have cost you north of $150K to build is ironic, the cost of a twin is an upward parabolic curve. The starter adapter example I gave is one thing, but consider the cost of buying and building an elevator for your RV-10. Now consider that a new elevator for a B58 Baron, in 2017 mind you, was $23,000 PER SIDE. I'm not sure that it's $1000 for all the parts to build a complete RV-10 elevator, but it's in that ball park - a much smaller park to play in.

I say all that to make the point that thinking about twins is fun, AND, I thoroughly loved flying my Baron, BUT, the cost of owning and operating a twin - even an experimental twin, is MUCH higher than the wonderful RV-10. Even more so, the importance of recurrent training One Engine Inoperative and being highly proficient on your airplane just about mirrors the O&M cost. Have fun, just have the right expectations, and bring your checkbook.
 
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I think you may mean that a good twin needs to be able to climb on one engine. I do not believe there is a certified twin, piston or jet, that allows take off with one engine inoperative, but your point is valid.

You're right that with most jets, you can't start the takeoff with an engine inoperative (some you can -- A380, B747, etc). However, with any transport category certified jet, it must be able to continue the takeoff after V1, and fly with an engine inoperative.
 
The next RV should be a twin IO-360 powered aircraft with available FIKI. It should be the size of a 10 and a good IFR platform.
There...I said it.:p
Put a pair of Rotax 914's in it. 200HP available to FL160! And you can run Mogas... Two of those together probably aren't far off a new IO-540 with prop and accessories, and I'd guess 100lbs lighter.:D
 
You're right that with most jets, you can't start the takeoff with an engine inoperative (some you can -- A380, B747, etc). However, with any transport category certified jet, it must be able to continue the takeoff after V1, and fly with an engine inoperative.

It might seem like splitting hairs, but continuing a take off after V1 with a failed engine is different than initiating a take off with a failed engine. Also, neither the A380 or B747 are twins. The POH for a Baron states that if an engine fails during takeoff to shut the throttles and do maximum braking. The same is true for a Diamond and Cessna twins, but I do not know if it's in all twin flight manuals.

However, a twin RV-10 would not have a V1, nor would it be certified, so it would be up the builder to decide. If you're in a hostile situation and you're going to die if you stay on the ground, give it a go, but realistically, anyone who has taken multiengine training knows that the worst case scenario for a twin engine aircraft is an engine failure on take-off (slow, heavy, gear down, asymmetric thrust, etc) - statistically, it's a high fatality rate. The only advantage of starting the take-off roll with OEI would be that you already know it's failed and hopefully prepared for it; but just because something is possible doesn't mean it's profitable; I do not advocate doing it.
 
Put a pair of Rotax 914's in it. 200HP available to FL160! And you can run Mogas... Two of those together probably aren't far off a new IO-540 with prop and accessories, and I'd guess 100lbs lighter.:D

I like it. You'd need to redesign the wing to handle the additional stress, but it would be cool. You might also want to stretch the fuselage - both changes might increase Vne, but either way, you'd definitely be expanding experimental aviation!

Note that you want the single engine to have enough power to allow the fully loaded aircraft to climb. Considering the RV-10 had a 210 horsepower option early on, it might work with turbo'd 200 hp. Another issue would be CG; You might need to build some fancy pylons to get the engines forward enough for that, or move the wing on them fuselage.
 
Certainly, all very interesting comments posted here but was I had in mind is certainly not anything close to a 50's-60's designs like a Twin Comanche/Aztec/Baron. What I'm talking about is an RV and like all RVs, a modern, fast, crazy simple, inexpensive (for a twin), all (almost all) weather go anywhere, fill ALL seats, IFR touring machine. Like all RVs a great bang for the buck.:rolleyes:
 
So sorry but had to make an observation
Yes there are multiengine jets that can accelerate
And take off on one engine. Been proven.
But the practically side is the available runway has to be over 8 thousand feet


I too have owned and instructed in a 1968 Cessna 310 N

It too would climb on one engine not great and you had to do all the right stuff ball in center slight bank into the operating engine etc. but with enough density altitude most piston twins can not climb on one engine.

Temperatures and altitudes have a lot of effects on the ability of a small twin to climb.
Thats why most pilots are safer in general aviation with one motor.
If it fails you only have one choice which direction your going.
 
Certainly, all very interesting comments posted here but was I had in mind is certainly not anything close to a 50's-60's designs like a Twin Comanche/Aztec/Baron. What I'm talking about is an RV and like all RVs, a modern, fast, crazy simple, inexpensive (for a twin), all (almost all) weather go anywhere, fill ALL seats, IFR touring machine. Like all RVs a great bang for the buck.:rolleyes:

Hmmm...

Modern - Yeah, that would be nice.

Fast - Well, if you base it around an RV-10 design, those 50's-60's designs will likely be faster.

Crazy simple, all weather, go anywhere - Well, that's an oxymoron...crazy simple and all weather, go anywhere are mutually exclusive, in general.

Inexpensive - What's your definition? A nice go anywhere, IFR RV-10 without FIKI is going to be in the $200k+ range...now double the engines, double the props, multiple additional systems...you are going to be WAY up there price wise. Now add in FIKI and watch the price go up.

Fill all the seats - Yeah, that would be nice, too. Add bigger engines, more fuel, more wing area, taller landing gear, etc...Jeesh this is sounding like a 737 design history!
 
Day Job

My day job is flying old Dash-8-100s. During my last simulator session, we had some spare time at the end. I asked the instructor if I could try taking off with an engine shut down and he agreed. So there we were, feeding in power as the rudder authority and steering permitted until we eventually reached rotation speed and up we went! Now this was a simulator, and I'm sure reality would have burned the tires right off the nosewheel, however it was possible. NEVER going to try that in a real airplane.

There's a rumour floating around that the Aero Commander, for it's single engine demonstration flight, flew to meet the FAA with one of the propellors in the cabin. They landed, taxiied in and reinstalled the propellor with the FAA watching. Not sure how true the story is, but it's fun to think about.

When I think of a modern, fast, crazy simple, inexpensive (for a twin), all (almost all) weather go anywhere, fill ALL seats, IFR touring machine, my brain thinks of a small King Air with most of the seats passenger seats removed. All-weather is a very daunting task requiring complexities and power, both of those things are expensive. Mother nature can throw a lot at airplanes. She has taken down stuff with far superior capability to anything with piston engines. Just because an airplane is certified for FIKI, doesn't mean it can handle all icing situations...ask me how I know :D
 
Twin

Not a 4 seater but definitely a hot twin. The trick is to get the company to offer a kit. They are shooting for the military/govt market but if someone was to convince them to offer a kit I’ll bet a lot of us would build one, me included.

http://www.speedtwin.co.uk/speedtwin-movie/



 
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Try a P337. Single engine ceiling is 14K. Engine out handles like a heavy 210. Probably the most stable IFR approach craft in the air.
 
Tri-motor -10

An RV-10 with 3 fuel injected rotax motors with integrated ecu?s, fly by wire throttles, And auto feathering props!!!
 
Wow, an aerobatic, fixed gear, taildragger, tandem seat twin. I like it!

(No offense to my British friends, but why are so many British airplanes (with the exception of the Spit, of course) rather, um ... homely looking? Is that part of their "Design Requirements and Objectives" document or something? Or is it truly a case of beauty is in the eye of the beholder? :D)

Couldn't agree more - aerobatic, fixed gear, taildragger, tandem seat twin. I like it too. It even looks like they took the tail from an -8. The rest does look a little homely, but impressive numbers.
 
I had a 1964 Cessna 320 Sky Knight. It flew great on one engine; fast and roomy...

The C-310R is a really nice twin, too. It also flew fine on one engine.

Now the early model Apache...not so much...

Don't hold back...revisit the Champion 402 Lancer with a single engine service ceiling of 2000 ft.
 
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