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RogerH

RogerH

Well Known Member
Had to knock out a bi-annual flight review yesterday . Flying an RV-4 without rear seat controls I opted to complete the review in a Rans S-21 Outbound.

Likely just "preaching to the choir" but I've never been more uncomfortable in an aircraft or happier to get back in my plane. I always considered the RV-4 to be a bit twitchy in Utah's turbulent summer air but WOW was I ever in for a surprise. Maybe the Rans makes sense flying grass strips in Kansas but totally out of place any where "thermally".

RV-4 ROCKS!!!

No particular point to this post, just thought I'd share my experience.
 
Curious - as I’ve read a lot of positive reviews on the S-21. Was it just the “bounciness” of a light wing loading, light aircraft that you noted? Granted, it’s hard to beat a RV! Can you further advise what you didn’t like? Not looking to bash the S-21, but I am keeping an eye out for other options. I see myself moving to a high-wing aircraft at some point as I age, as much as I love my 9A. I want to love the RV-15, but being designed/optimized around the very expensive IO-390, I’m not sure it’ll be an option.
 
I'll be watching this thread. It's been my impression that the S-21 has been popular among RV builders looking for another project in the high wing/back country category. My take was the RV-15 was a play to win that group back and attract new back country builder/flyers to the brand. I've occasionally provided helping hands to a good friend building one and look forward to getting to eventually fly in it.
 
RogerH said:
Had to knock out a bi-annual flight review yesterday . Flying an RV-4 without rear seat controls I opted to complete the review in a Rans S-21 Outbound.

Likely just "preaching to the choir" but I've never been more uncomfortable in an aircraft or happier to get back in my plane. I always considered the RV-4 to be a bit twitchy in Utah's turbulent summer air but WOW was I ever in for a surprise. Maybe the Rans makes sense flying grass strips in Kansas but totally out of place any where "thermally".

RV-4 ROCKS!!!

No particular point to this post, just thought I'd share my experience.
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Before my RV-14A was finished had to do a few BFR's in a 172. I would not be still flying today if I did not have a RV. Call me spoiled......
 
I built an S-21 a couple of years ago and now have a companion aircraft to my RV-6. Love them both. Hard to say which one I like better...different experiences each. Kind of makes it more fun alternating between the two. Flying one makes me look forward to flying the other again. I don't think I could part with either one...unless I order an RV-15!
 
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Phyrcooler said:
Curious - as I’ve read a lot of positive reviews on the S-21. Was it just the “bounciness” of a light wing loading, light aircraft that you noted? Granted, it’s hard to beat a RV! Can you further advise what you didn’t like? Not looking to bash the S-21, but I am keeping an eye out for other options. I see myself moving to a high-wing aircraft at some point as I age, as much as I love my 9A. I want to love the RV-15, but being designed/optimized around the very expensive IO-390, I’m not sure it’ll be an option.
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No it was more than a wing-loading issue. Stick forces were extremely light. Anything beyond two-fingers and more than about 3/4" of stick movement was excessive. Also seemed much more susceptible to turbulence upset than I'm used to in the RV4.

Also for a tricycle gear I thought forward line-of-sight was limited compared to the TW -4.

Apparently it was serial #1 for that model so that may have been a contributing factor.

Your experience may vary. I suggest you fly one before putting down a kit deposit, you might love it but best to know before putting a couple of years into the project. I once had a deposit on one but backed off when the whole COVID thing flared up and frankly glad I did.

On the plus side I was impressed by the Rotax, quiet & easy to operate.
 
RogerH said:
No it was more than a wing-loading issue. Stick forces were extremely light. Anything beyond two-fingers and more than about 3/4" of stick movement was excessive.
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That's a good thing really. Past Rans stuff was often dead and/or stiff. Other than extremely light, how did the controls feel? Are the ailerons a folded trailing edge like the 4-6-8?

As for wing loading, those of us who made a detour through the Cub community are unlikely to be bothered. Not an uncommon story, but I once had to wait on the apron at Gulf Shores, idling into the wind, until the line guys came and got me.

I imagine the wing loading on the RV-15 will also be lighter.

L4c Warbirds 800w.jpg
 
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DanH said:
That's a good thing really. Past Rans stuff was often dead and/or stiff. Other than extremely light, how did the controls feel? Are the ailerons a folded trailing edge like the 4-6-8?

As for wing loading, those of us who made a detour through the Cub community are unlikely to be bothered. Not an uncommon story, but I once had to wait on the apron at Gulf Shores, idling into the wind, until the line guys came and got me.

I imagine the wing loading on the RV-15 will also be lighter.

View attachment 88666
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Sorry, can't really provide any feedback. On a bi-annual I was more focused on flying and not aileron construction. As far as control feel, yup, when I pushed the stick left & right the plane banked left & right. :cool:
 
DanH said:
I imagine the wing loading on the RV-15 will also be lighter.
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As a thought experiment...

The two-place Lycoming-powered RVs all have wing loadings in the range of roughly 14-16 lb/ft² at max gross. The RV-10 is heavier at 18.6 lb/ft².

Using the most recent values for gross weight and wing area I can find (2050 lb / 160 ft²) gives a projected wing loading of 12.8 lb/ft² for the RV-15.

The Rans S-21 has a wing area of 141 ft². Depending on your choice of engine and how you certify it, the wing loading can be anywhere between 9.4 and 12.8 lb/ft².

And while I'm at it, a Carbon Cub EX-3 clocks in at 11.4 lb/ft², while the classic J-3 is a featherweight at only 6.7 lb/ft².

So I think that Mike with his Lycoming-powered S-21 is pretty much getting the equivalent RV-15 wing-loading experience. The OP was probably bounced around a great deal more in a Rotax powered S-21, whose gross weight I assume was on the low end of the various weights allowed for that airframe.
 
DanH said:
That's a good thing really. Past Rans stuff was often dead and/or stiff. Other than extremely light, how did the controls feel? Are the ailerons a folded trailing edge like the 4-6-8?

As for wing loading, those of us who made a detour through the Cub community are unlikely to be bothered. Not an uncommon story, but I once had to wait on the apron at Gulf Shores, idling into the wind, until the line guys came and got me.

I imagine the wing loading on the RV-15 will also be lighter.

View attachment 88666
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Been there Dan. My first airplane was a ‘42 L3. The “operating instructions” stated “do not operate aircraft when winds are 25mph or more.”
Mine wasn’t as nice as your example.
It was a lot of fun to fly, I leaned in it. It would have been a great compliment to an RV. The Bucker replaced it, but unlike the L3, it’s solid as a rock in the breeze and bumps, and 40mph faster.
I can see the appeal of the Rans.
 
mburch said:
As a thought experiment...

The two-place Lycoming-powered RVs all have wing loadings in the range of roughly 14-16 lb/ft² at max gross. The RV-10 is heavier at 18.6 lb/ft².

Using the most recent values for gross weight and wing area I can find (2050 lb / 160 ft²) gives a projected wing loading of 12.8 lb/ft² for the RV-15.

The Rans S-21 has a wing area of 141 ft². Depending on your choice of engine and how you certify it, the wing loading can be anywhere between 9.4 and 12.8 lb/ft².

And while I'm at it, a Carbon Cub EX-3 clocks in at 11.4 lb/ft², while the classic J-3 is a featherweight at only 6.7 lb/ft².

So I think that Mike with his Lycoming-powered S-21 is pretty much getting the equivalent RV-15 wing-loading experience. The OP was probably bounced around a great deal more in a Rotax powered S-21, whose gross weight I assume was on the low end of the various weights allowed for that airframe.
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Perfect analysis Matt - the Lycoming powered S-21 is a very nice-handling machine - I have always enjoyed flying it. With a Rotax, it is going to be lighter and have less penetration. In the Cub world, I was recently playing around with the IO-390 powered NX Cub….think about that - the same engine as the RV-15 is now flying in a smaller airframe. Yes, it bumps around, but holy cow, does it climb!
 
mburch said:
As a thought experiment...

The two-place Lycoming-powered RVs all have wing loadings in the range of roughly 14-16 lb/ft² at max gross. The RV-10 is heavier at 18.6 lb/ft².

Using the most recent values for gross weight and wing area I can find (2050 lb / 160 ft²) gives a projected wing loading of 12.8 lb/ft² for the RV-15.

The Rans S-21 has a wing area of 141 ft². Depending on your choice of engine and how you certify it, the wing loading can be anywhere between 9.4 and 12.8 lb/ft².

And while I'm at it, a Carbon Cub EX-3 clocks in at 11.4 lb/ft², while the classic J-3 is a featherweight at only 6.7 lb/ft².

So I think that Mike with his Lycoming-powered S-21 is pretty much getting the equivalent RV-15 wing-loading experience. The OP was probably bounced around a great deal more in a Rotax powered S-21, whose gross weight I assume was on the low end of the various weights allowed for that airframe.
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Great synopsis, and relatable. My RV-9A is listed in Van’s specs at 12.9 - 14.1 lb/ft2. I’ve flown the RV-12 and it is listed at 10.4 lb/ft2. So this all makes sense. As far as controls - I think the 9 is pretty light, but not too light. Very pleasant. And I’m sure this is heresy, but I do think the throw is shorter than necessary by a wee bit. When I let a non-RV pilot take the stick, I tell them - Don’t move the stick. Think with it! 😂 Thumb and two fingers. I’ve not flown a -4. I look forward to flying in the RV-15 as well as the S-21 someday.
 
Mike S said:
As an builder/owner/flyer of a S21, I found the kit and finished aircraft to be just what I wanted these days.

Different mission, and different aircraft for sure.

Although a RV4 and a S21 would make a great pair to cover many facets of flying enjoyment.
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I think we all strive to be like Paul with a hanger full of our favorites!
 
My bearhawk with extended wing tips is around 185sq/ft for a wing loading of 13.5.

But that’s a 4 place airplane at gross. With me, my wife, 2 mountain bikes, a campsite, a cooler, little BBQ, some Bohdizafa, and 40 gallons of gas, should be around 12.

There isn’t an RV that will fly that mission, not even the 15, unless I swap to folding bikes.

Going fast is cool, but I live in a beautiful corner of the PNW, so there isn’t anything I really want to travel to more than 6 hours away and I’m not willing to trade my bikes, BBQ, and cooler for 2 hours faster.

Like I said, depends on the mission.
 
RV-4 has a pretty light wing loading. I've been practically beaten to death a few time in rough air. When your head bangs into the bottom of the canopy you know it's time slow down. Not fun.
 
My wife had a RANS S7 fun plane but it was determined to be too light for flying those 900 mile trips, that she took often, in the middle of the hot summer days.
 
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akschu said:
My bearhawk with extended wing tips is around 185sq/ft for a wing loading of 13.5.

But that’s a 4 place airplane at gross. With me, my wife, 2 mountain bikes, a campsite, a cooler, little BBQ, some Bohdizafa, and 40 gallons of gas, should be around 12.

There isn’t an RV that will fly that mission, not even the 15, unless I swap to folding bikes.

Going fast is cool, but I live in a beautiful corner of the PNW, so there isn’t anything I really want to travel to more than 6 hours away and I’m not willing to trade my bikes, BBQ, and cooler for 2 hours faster.

Like I said, depends on the mission.
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Agreed, although sitting by the campfire sipping a "Bohdizafa" for two hours waiting for you to arrive does have some appeal. :)
 
71459 said:
RV-4 has a pretty light wing loading. I've been practically beaten to death a few time in rough air. When your head bangs into the bottom of the canopy you know it's time slow down. Not fun.
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I saw a flowchart somewhere — I can’t remember where — but it was from an RV pilot and one of the branches said “Did you just hit your head on the canopy?”. If the answer was “yes” it said “Welcome to the club. Slow to Va” and if it was “no” it said “You’re not a real RV pilot yet. Keep on trucking’” or something to that effect. If had a whole matrix of stuff like that. One was for flap motor failure. Another was for landing gear shimmy.

I wish I had saved a copy.
 
BoydBirchler said:
My wife had a RANS S7 fun plane but it was determined to be too light for flying those 900 mile trips, that she took often, in the middle of the hot summer days.
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I've had an S-7S for the last year and a half and have to agree. With a wing loading of about 8 lb/sqft, it's a very harsh ride in any kind of wind or thermals. When I first got it, I imagined I'd do a little camping in it, but the reality is it's just not that fun to fly when it gets hot and windy. Super fun little airplane otherwise.
I'm looking at a replacement airplane/retirement project, and the S-21 and RV-15 are at the top of my list. I'm starting to lean toward the RV-15 though, for what appears to be a more robust and capable airplane.
 
Current Aviat Husky A1b owner... considering the S21and RV-15; the 15 is shaping up to be a very nice aircraft, and very similar to the S21, having only the advantage of size/payload, at the cost of more $$. I really like the 4130 steel cage of the Rans; I think that's a better design over full monocoque construction for the intended mission (rough strips and unfavorable terrain in case of a mishap). The S21 has very nicely harmonized and fairly light controls, and is FAR more stable in yaw than my Husky. The wing loading will make both planes a similar ride in turbulence, but the yaw stability will make the S21 wallow much less. (RV-15 should be similar in that respect).
 
Muttley said:
Current Aviat Husky A1b owner... considering the S21and RV-15; the 15 is shaping up to be a very nice aircraft, and very similar to the S21, having only the advantage of size/payload, at the cost of more $$. I really like the 4130 steel cage of the Rans; I think that's a better design over full monocoque construction for the intended mission (rough strips and unfavorable terrain in case of a mishap). The S21 has very nicely harmonized and fairly light controls, and is FAR more stable in yaw than my Husky. The wing loading will make both planes a similar ride in turbulence, but the yaw stability will make the S21 wallow much less. (RV-15 should be similar in that respect).
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The s21 has very thin skin. My buddy took one into the backcountry and sustained damage to the skins. No thanks…
 
wnplt said:
The s21 has very thin skin. My buddy took one into the backcountry and sustained damage to the skins. No thanks…
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Yeah, I hear that the bottom elevator skin takes a beating on the S21. The truth is that any plane that gets used off airport will get beaten up... it'll be nice to have replaceable leading edges on the elevator of the 15!
 
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