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What class of bushcraft do you think they are working on?

Crashworthiness

You could crash your aircraft at 55 or less and as long as you don't hit something that brings you to a sudden stop, you should survive.........:eek:

Interesting theory. Your odds of survival are certainly better at lower impact speeds. Depending on how rapid the deceleration, structure still plays a big part. If Vans decides to put a full wing spar right in front of the two front occupant's heads, that 55 mph could still leave a mark. If they put the fuel tank above your legs like Sonex, that could get interesting as well.

Here in congested Southern California, good luck finding wide open spaces to do a gradual rollout from 55 to 0 mph. Nevertheless, I'd rather do it at 55 mph than 63 mph in my current airplane.
 
Ya I know slower is better but I didn't know if that 55 number was statistically significant or not.
 
Interesting theory. Your odds of survival are certainly better at lower impact speeds. Depending on how rapid the deceleration, structure still plays a big part. If Vans decides to put a full wing spar right in front of the two front occupant's heads, that 55 mph could still leave a mark. If they put the fuel tank above your legs like Sonex, that could get interesting as well.

Here in congested Southern California, good luck finding wide open spaces to do a gradual rollout from 55 to 0 mph. Nevertheless, I'd rather do it at 55 mph than 63 mph in my current airplane.

Van's won't do that. It will be above, behind or placed where your head will not hit it. IF you flip, you will want that spar there. Your chance of walking away, and even flying the airplane out are very good.
 
Curve

If I recall, Vans had a graph with a curve on it that showed the relationship between speed and survivability, using data from I guess years of information. I don’t think the point was the actual 55 number, but rather the desire to try and keep the stall speed on the lower end of the spectrum. I remember looking at the White Lightening and Lancair stalls speeds on the graph and it was humbling. The survivability curve got exponentially worse above 55 to 60mph. One thing that stands out in my mind was the amount of concern that Van gave this when he was designing his planes.

Ya I know slower is better but I didn't know if that 55 number was statistically significant or not.
 
If I recall, Vans had a graph with a curve on it that showed the relationship between speed and survivability, using data from I guess years of information. I don’t think the point was the actual 55 number, but rather the desire to try and keep the stall speed on the lower end of the spectrum. I remember looking at the White Lightening and Lancair stalls speeds on the graph and it was humbling. The survivability curve got exponentially worse above 55 to 60mph. One thing that stands out in my mind was the amount of concern that Van gave this when he was designing his planes.

I will have to look for that graph. Would like to see where the -10 falls on the curve.
 
My need is for C182/206 version of an RV10 high wing.

Tricycle
4 seats
6 cylinder rv10 performance
upgrade path for a turbo, mid teens cruise
Easy to get in and out of
A big baggage door to rear seats and baggage area
Option for installing a BRS chute

The C206s are in very high demand for back country work. As they say the professionals choice.
 
Vans just posted a teaser on FB with the the RV-15 covered up in the background :eek:
 
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Hah. That was actually the RV-5 with something that's not really the RV-15 covered up in the background.

Ah-Ha! See?,,,Still more evidence that recently released photos of the "RV-5" are actually Spy photos of the RV-15!

"You can fool all of the people some of the time, and you can fool some of the people all of the time. But you can't poop an old pooper!"
(Some words changed to meet rules)
 
https://www.kitplanes.com/kitfox-announces-new-model-with-stunning-new-rotax-engine/

Rotax918.jpg


Looks like a new option?

Bob
 
yes, the date is April 2021? It takes a while to get a new engine out the door and be adopted. Looks like Kitfox may be trying it out....

Bob
 
LOL! - Well that would be a bummer, but you all are probably correct!

Thanks! :(

Bob

yelp color me fooled :) Well back to where I belong - LyCons...
 
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There is no rotax 918 engine.

If you look at the picture, the middle cylinder doesn't have any exhaust port........ And the middle exhaust pipe ends on the rear cylinder.
 
LOL! - Well that would be a bummer, but you all are probably correct!

Thanks! :(

Bob

yelp color me fooled :) Well back to where I belong - LyCons...

Sorry, but yes it was an April Fools Joke. But I would not be surprised if Rotax built a higher HP engine in the near future.

It is a bit of a tough one though, I am about to begin a Bearhawk build and have been flying behind a 915iS for a while and LOVE it. But the BH just can’t be built (barring extensive FWF modifications and fabrication well beyond my abilities) due to the fore/aft W&B. It was designed for an engine in the 300# range, and the 915 is a 187# engine, maybe close to 200# if you tried. But at the furtherest most forward arm it is not gonna stay in the CG envelope. And I am not a fore of a aft CG guy so it was out of the question.

So, with the above being said, will they build a 180hp turbo engine for only the current market? Or will they try to break into the 10’s of thousands of LyConti’s already out there? Would they build a 180hp normal weight for the Vans, Kitfox and Rans crowd and a heavier model for the legacy crowd?
 
Pete Bartoe, who also designed the Skyote biplane, gave a talk to my senior aerospace engineering class back when. He described this and predicted the performance he got, and discussed the technical features. It was built at Boulder, I believe, as a homebuilt.

Dave
 
If I recall, Vans had a graph with a curve on it that showed the relationship between speed and survivability, using data from I guess years of information...

I vaguely remember having seen something like that, so I did some quick Googling.

Rich Stowell generated the following graph from data off an SAE study about light plane crashworthiness. More details in this IAC article. Notice that the angle (presumably the angle off the horizontal) plays a key role: At 90 degrees nose-down (nose-dive), anything above 45mph is deadly. But at zero degrees (belly-flop) you could survive hitting the ground at 75mph, according to the data.

Emergency%20Landing%20Survivability%20chart.png


Ron Wanttaja writes lots of terrific articles about light airplane safety, accident rates, accident causes, etc. If you don't know his work, you must check it out. Below is a graph from this article. Although it ranks kitplanes not by speed but by fatal accident rate, you can't help but notice that the ones in the lower left (safest) are generally the slowest, and the ones on the upper right (more fatal accidents) are the fastest. The RV-4/6/8 are slightly above the line.

safety-table5.jpg


Finally, it's no surprise that the automotive industry has all kinds of statistics about this. They're not so relevant to us - because cars are different kinds of vehicles, are built differently and move through space differently - but the trends are interesting. Two graphs below, one from here and one from here.

Wramborgs-model-for-fatality-probability-vs-vehicle-collision-speeds-Source-based-on.png


Screen-Shot-2016-05-27-at-1.28.41-PM.png


In the end, I have to admit that I feel a little more peace-of-mind when I fly a slower airplane versus a fast RV because I know that, if I have to make an emergency landing, I'll be more likely to walk away from the slower airplane. I've heard pilots say - and I agree - that "The Cub is one of the safest airplanes out there; It's barely fast enough to kill you" ;)
 
RV15 Prototype?

Having been blessed to fly a wide variety of aircraft I definitely have my favorites. High on the list is the F16 and the RV4. Right there with though is my tried and true Maule M5.
The similarities between Vans Aircraft and Maule Air Inc are to the most casual observer uncanny. Both humbly began with quiet genius engineer dreamers building a prototype aircraft in a barn after the factory built aircraft didn't add up. Both aircraft (M4 and RV3 prototype) won best new design award at the EAA convention. Both are legendary in their own rite.

Where they differed was one went into production as a certified aircraft, the other into the most successful kit aircraft company in history. So why the M5 comparison?
My M5 180's (0-360) GW perf numbers are impressive even today, the 0-540 powered models even more so. With equal power (Vans uses the same engines historically) it's a good bar for the RV15 to match or hopefully raise.

Maule M-5-180C -GW Performance Data

Horsepower: 180 Gross Weight: 2300 lbs
Top Speed: 157 kts Empty Weight: 1300 lbs
Cruise Speed: 136 kts Fuel Capacity: 40 gal (65 with Aux tanks)
Stall Speed (dirty): 33 kts Range: 525 nm

Takeoff Landing
Ground Roll: 200 ft
Over 50 ft obstacle: 800 ft Over 50 ft obstacle: 600 ft

Rate Of Climb: 900 fpm
Ceiling: 15000 ft
Wingspan 29'6"
Length 26'3"


So I'm expecting great things from Van with the advent of The Fifteen, although the M5 (M7 and 9) casts a large albeit similar shadow...
:)
V/R
Smokey
 
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Different Engine

I wonder if Vans might consider at least designing the possibility of using a non- Lycoming engine. If they are doing a 4 seater high wing the UL Power 520 T seems like a interesting option. It provides the same sort of sea level performance as the IO-390 but you are still getting close to 220 HP at 15,000 ft.

It also has the advantage of being about 40lbs lighter and FADEC controlled and uses mogas. The problem is it doesn’t have the pedigree of a Lycoming. However for those who want a reasonably quick 4 seater high wing it sounds like a decent option.
 
Smoky is Right On

Smoky was flying his RV4 to Idaho and telling Doug and I about the fun,,,,, way back. I became hooked.
The N Texas RV crowd were already flying to Vans SunSet air strip for Home Comings. So we were used to the Distance….
About the time Van moved to Aurora ,,,, we found the Back country,,, thanks to Rob Smoky Ray. Not as talented as Smoky, But interested, And with much trepidation ,, I took my RV6 into Indian Creek, Johnson Creek, Big Creek, and Moose Creek, Idaho. I thought those places were a little hard on my plane. So.

2004 . I built a North Star Super Cub Kit with 180 Lycoming, 31” Bush Wheels. Very capable,,,,,,. but 90 knots, 15 hours to get to Idaho from My home base Hicks T67. Never thought about a Maul, Smoky,, ? Guess Learning in 172s clouded my thinking?
I new back then I wanted a high wing RV,,, that would go 130 knots! With bigger tires. Enter my Cessna 180J in 2009.

The C180 is capable and is a great back country plane, just wish I could have built it my self. From a kit. I do wish it was a little faster… I call it Paul Revere
 
Maule M-5-180C -GW Performance Data

Horsepower: 180 Gross Weight: 2300 lbs
Top Speed: 157 kts Empty Weight: 1300 lbs
Cruise Speed: 136 kts Fuel Capacity: 40 gal (65 with Aux tanks)
Stall Speed (dirty): 33 kts Range: 525 nm



Are you saying a 180 hp Maule will cruise at 157kts?
 
He's saying it will cruise at 136 knots, Top speed 157 knots.

I checked the Maule website and the stated speeds should be in MPH, not knots. So 136 mph cruise & 157 mph top speed. (At least for the new 180 hp models)

BTW. I quite like Maules. I thought about getting one before I got into the world of RV’s.
 
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Maules are basically Piper Pacers with larger engines. It's rare to cruise at book speed in 180hp Maules....more like 115 mph. They are cool in their own way:p
 
Speed or not

Yes, the book numbers vs real world on my M5 (like many airplanes except the F16) vary greatly. It took me 100 hours to get my RV4 up to Vans factory claims, but it was worth it.
My real world M5 cruising speed numbers with the 180/Hartzell, 700:6 tires and all fairings in place are:
135 mph (118 Knots) at 24-24 2500'’ 20/23 yields 120 mph/105 KTS. The really cool number is a 550’ takeoff roll at GW...

Recent trip to FL at 7500' with Grandkids, dog and gear I averaged 122 KTAS at 8.2 GPH. Not bad considering the 1000# load. Per the factory sticker on the VS, Maules were designed for STOL and that is where they excel.
Higher Cruise speed notwithstanding there are other attributes not discussed on this site as much that really matter in the more austere reaches of the world.

The RV15 with an 0-360 should exceed my M5s capabilities (I hope) for a similar size and weight. I’m certain Van has looked at several airplanes the M5 included for their design. It’s still a great airplane.

Recent discussion on the Maule forum on this very subject:
http://maulepilots.org/Hangartalk/viewtopic.php?t=6440

V/R
Smokey

https://youtu.be/0x5bKaq0p5U
Great Video of an M5-180 in its element.
 
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I have it on good authority the latest iteration of the 15 has morphed into this:
 

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My thoughts

I think and I’m hoping it’ll be typical Vans. That is metal, riveted, side by side, two place, sticks, Lycoming 360/390, with a great wing, 36’, like the Riblett on the BearHawk Patrol. I hope it’ll have skylights, manual flaps, and two piece doors with the bottom swinging open on forward hinges and the top swinging up on top hinges, able to stay open in flight. I don’t think they’ll move too far out of their comfort zone. Easy to build a four place version too. Was getting close to pulling the trigger on a 9 when the announcement came at OSH.
 
two piece doors with the bottom swinging open on forward hinges and the top swinging up on top hinges, able to stay open in flight..

I would much rather see it done like the Glasair sportsman - where the single wing strut attaches behind the door and allows for a large door that can swing all the way forward
 
I would much rather see it done like the Glasair sportsman - where the single wing strut attaches behind the door and allows for a large door that can swing all the way forward

As a Sportsman owner I can add that cockpit accessibility is GREATLY enhanced through having the strut in this location. My wife is mobility challenged. If the strut were located forward like a typical Cessna there is no way she would be able to fly with me, she simply would not be able to get into the airplane.
 
CAN-Tilever you say?

As a Sportsman owner I can add that cockpit accessibility is GREATLY enhanced through having the strut in this location. My wife is mobility challenged. If the strut were located forward like a typical Cessna there is no way she would be able to fly with me, she simply would not be able to get into the airplane.

Of course, the cantilever wing eliminates that strut issue altogether! (as mentioned above)
Been done before, quite well I might add...:)



The Lockheed Vega, Cessna 190/195 and many other WW2 era high wing airplanes also shared the cantilever wing. Many advantages not the least of which is accessibility.

V/R
Smokey
 
Honest question … how does one get to the fuel tank on a cantilevered wing, without a stepladder? I’m often fueling from cans in deepish snow, on my 170 I can use the strut to balance while I climb up there. The supercub on floats has a step on the gear, but still use the strut to balance. Ladder is inconvenient to have to carry, sketchy at best in the snow, not doable on a beached floatplane…

I’m sure there’s a way, the helio is a real off airport machine. I hope the 15 ends up with a practical way to fuel away from pavement.

I also think a strut based design is probably lighter. The access to my 170 is great, the door opens very wide, and it’s quite easy to get in. Strut behind the door would be hard on a taildragger with big tires wouldn’t it?
 
First, I've never been in a cantilevered high wing...


With a cantilevered high wing, how's head room?

What about skylights with a cantilevered high wing?
 
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