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RV-4 vs. -7

mattsrv7

Well Known Member
Here's an opinion question for folks that have a bit of time flying both the -4 and -7 primarily for acro.

I have a flying 150 hp fixed pitch RV-4 with manual flaps and trim. I really like the handling qualities, awesome visibility, simplicity, and aerobatic capabilities of the -4. The more I fly it, the more I like it. I'd originaly thought about it as something to fly until the -7 is done but I'm questioning that path.

I did transition training in an RV-7 and was surprised how well RV's glide vs. the Steen Skybolt biplane I had previously.:). The few hours I have in a -7 were concentrated on takeoffs and landings and I didn't do any acro, so I don't have a great reference.

The one thing my -4 doesn't have is inverted fuel and oil. I miss the inverted systems I had on the Skybolt a bit and had plan to have them on the -7 I'm building. I regularly did outside acro in the Skybolt so I understand what trusting your seatbelt means. Adding these systems to this particular -4 would require enough rework of the fuel tank, sump, and firewall forward that it isn't worth considering unless pulling the engine for an overhaul.

I have an RV-7 quickbuild fuselage and completed tail in the garage with most of the things done needed to be ready for the finish kit. I'm at a point where I have to start adding the expensive bits to really move the project forward.

If a -7 is kept light and setup for aerobatics, can it be comparable to the light connected feel you get with a lighter -4? I'd been thinking of minimal equipment and a fixed pitch prop with a higher compression -320 (used) or -360 i (new)n the -7. It seems like most -7's have amazing panels but I'm viewing mine more as a Cap-10. I have no real resale value concern.

Anyone have any opinions who has a bit of time using both the -4 & -7 as an acro/ sport plane? Do you think I'd be happy with a -7 from what I describe above?
 
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I have more time in a 6 than 7 and also have a few hours in a 4. A 7 will be 100 to 150lb heavier than a light 4, so will never feel as light and connected. A 4 is a better aircraft for acro, but think carefully about what you really want to do. I would definitely put an injected 180 in a 7, and also think about a c/s prop. It is relatively easy to retrofit an expensive panel, I don't think that would be an issue.

Do you fly acro with a passenger? If no, could you sell the 4 when the 7 is nearly ready and buy into a Pitts (or similar) partnership? If you keep the 4 retrofitting a flop tube is not easy, you might also consider high compression pistons to give you an immediate 10+ hp increase.

Pete
 
-4 > -7 (My Opinion)

My experience is with my own -4 (160hp, FP, Manual Flaps, No Inverted System) versus Dad's -7 (180hp, CS, Electric Flaps, No Inverted System, Glass/IFR).

There is a definite control feel difference between the two (300 hours in the -4, 100 hours in the -7) and I'm slightly partial to the -4. The -7 has this weird aileron stall/buffet when you go full deflection in a roll that I've only been able to produce once in my own -4. Happens every time in the -7.

But if the -4 is a 10/10, the -7 is a 9/10.

My own personal opinion; I rarely have a flight in either airplane where I don't go upside down at least once. But all Gentleman Acro. Rolls, Barrel Roll, point rolls, the occasional Loop, Half Cuban... Nice and easy, think Bob Hoover "Energy Management" stuff. 3.5G pulls MAX in a loop or anything vertical. I have done the Primary Sequence a couple times in my -4 and even that felt abusive to my little hot rod. Whenever a friend asks for an airplane ride, I generally always use Dad's -7 because of CG issues (we're not all 170#'s...) and it does everything in the Gentleman Acro book just fine. But I would never want to do anything more. Like I said, it FEELS abusive. I do have a little bit of Extra/Laser/Pitts time, and I know what it feels like to somewhat reef on an airplane. I don't feel like the RV is in the that bracket. That's just my opinion.

Even though I have the -4 and love the Aerobatic handling qualities of that, I still daydream and browse Barnstormers.com for a Pitts S-1 or One Design occasionally. If I'm going to pursue hard acro more, if I feel the need to do anything more negative, I'll be buying a steed that is more purpose built.

TL/DR: I like the -4 better than the -7, an although capable, I wouldn't do inverted "Skybolt" acro in either. Feel's abusive to me.
 
TL/DR: I like the -4 better than the -7, an although capable, I wouldn't do inverted "Skybolt" acro in either. Feel's abusive to me.

I get that you're simply stating your preference for lazy acro, but the +4.5G and (momentary) -1G required to fly lower category IAC sequences are not remotely "abusive" to the RV airframe. Myths about RV acro are widespread and just don't want to see them perpetuated is all...not that I believe you are deliberately contributing.
 
Acro -4

Here's an opinion question for folks that have a bit of time flying both the -4 and -7 primarily for acro.

I have a flying 150 hp fixed pitch RV-4 with manual flaps and trim. I really like the handling qualities, awesome visibility, simplicity, and aerobatic capabilities of the -4. The more I fly it, the more I like it. I'd originaly thought about it as something to fly until the -7 is done but I'm questioning that path.

I did transition training in an RV-7 and was surprised how well RV's glide vs. the Steen Skybolt biplane I had previously.:). The few hours I have in a -7 were concentrated on takeoffs and landings and I didn't do any acro, so I don't have a great reference.

The one thing my -4 doesn't have is inverted fuel and oil. I miss the inverted systems I had on the Skybolt a bit and had plan to have them on the -7 I'm building. I regularly did outside acro in the Skybolt so I understand what trusting your seatbelt means. Adding these systems to this particular -4 would require enough rework of the fuel tank, sump, and firewall forward that it isn't worth considering unless pulling the engine for an overhaul.

I have an RV-7 quickbuild fuselage and completed tail in the garage with most of the things done needed to be ready for the finish kit. I'm at a point where I have to start adding the expensive bits to really move the project forward.

If a -7 is kept light and setup for aerobatics, can it be comparable to the light connected feel you get with a lighter -4? I'd been thinking of minimal equipment and a fixed pitch prop with a higher compression -320 (used) or -360 i (new)n the -7. It seems like most -7's have amazing panels but I'm viewing mine more as a Cap-10. I have no real resale value concern.

Anyone have any opinions who has a bit of time using both the -4 & -7 as an acro/ sport plane? Do you think I'd be happy with a -7 from what I describe above?

I have a -4 (500 hrs in it), it does have inverted fuel, but not oil.
Only makes a belly mess when my oil is over 5 1/2 qts full.
Plenty of acro, but if I have a passenger, I stay light on fuel load.

Re: the -7 it is heavy, and side-by-side, which I do not prefer for acrobatics.It can be done of course, just a preference.
Today I did my "short routine" and 4.0Gs.
I do not tire of it.

Daddyman
 
RV-4 / RV-7

The -4 has an small tight cockpit, it fits like a glove, in the air it feels much better tossing around than any of the other RV's I have flown.

Get a ride in an good inverted aerobatic A/C, then fly your -4 inverted level for about 10 seconds, and you won't waste your money.

My -4 had inverted fuel and oil & C/S prop, I removed The 801 system due to the weight up front.

Just my opinion!

gs
 
Four is more

Here's an opinion question for folks that have a bit of time flying both the -4 and -7 primarily for acro.

Anyone have any opinions who has a bit of time using both the -4 & -7 as an acro/ sport plane? Do you think I'd be happy with a -7 from what I describe above?

Matt
I built my light, basic unpainted 925lb, 150HP wood propped non inverted fuel/oil Four while flying F16's in Japan many moons ago. This was before the Six prototype had even flown. Since then I've had a chance to fly all the models including the Seven with various powerplants and props.

Inverted fuel and oil?
I performed parts of the Sportsman aerobatic routine or dog-fought with my fellow F16 bros in other RV's, Yaks, etc pretty much every chance I got to fly. The lack of an inverted system was never a hindrance. Unless you like to hang from the straps, pull negative G's or sustain inverted flight, the extra complexity, cost and additional weight isn't worth it IMHO. For what you are planning it's unnecessary. Here is my 180HP carbureted Catto prop RVX doing some positive G sport acro with....no inverted system.

https://youtu.be/LgrVhdZde5U

Four vs Seven? Personally,there is no comparison. The RV4 is (still) a much better bang for your sport-plane buck. By the time you finish a 7, you have nearly 100K invested. It's flight characteristics are no better and it's heavier and less "fun" IMHO. If you do alot of cross country or like staring at a glass panel with the autopilot on rather than at the sky upside down, maybe the Seven is for you. I think the RV4 it's much more fun to fly and closer to the "fighter feel" I enjoy. (My Harmon Rocket was even more so)

I once told Van a few years back that "He should have stopped designing sport-planes with the RV4, perfection was achieved".
He grinned and walked away...:)

V/R
Smokey
 
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Smoky Ray was the only one who mentioned cross country flights.

You have a -4 so you already know its limitations. I still remember my first trip to OSH with a buddy and reaching in back for the cooler for lunch, something you can do in the -7 but ntthe -4.

If all you do is take local flights, the -4 is amazing! However, the -7 would blow your socks off, had you never flown a -4.

Keep it light, put a 180 hp in it, with a composite CS prop, if you must. The CS prop is almost a requirement, if you are going to do formation work.
 
RV-4

I have flown mine from Seattle to Ohio on the purchase. A few trips to S. FL. and back, as well to Colorado springs. All were solo flights.

I fold the charts prior to flying, the put in order of need. It was more fun than flying around in an Aerostar 601P or the Duke B60, in the flight levels. the latter two A/C took less planning for weather, but the fun factor was not there. Again most of my flying has been solo. The wife is not fond of falling upside down.

Bang for the buck any RV is great, pick what fits you.

gs
 
RV-4

I have flown mine from Seattle to Ohio on the purchase. A few trips to S. FL. and back, as well to Colorado springs. All were solo flights.

I fold the charts prior to flying, the put in order of need. It was more fun than flying around in the Aerostar 601P or the Duke B60, in the flight levels. the latter two A/C took less planning for weather, but the fun factor was not there. When I had people along in those, I could not get her and the kids to pay!

The cost of operation on those was, out of the question after I quit working & even before was stupid.

Again most of my flying has been solo. The wife is not fond of falling upside down as she aged. I don't feel the need of high -Gs at my age either.

Bang for the buck any RV is great, pick what fits your your likes.

Gary
 
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